Fix build, remove unmaintained Django & Python versions.

Update .travis.yml

Update tox.ini

Update test_cachefiles.py

Update test_optimistic_strategy.py

Update test_no_extra_queries.py

Update test_cachefiles.py

Update .travis.yml

Update tox.ini

Update .travis.yml

.gitignore

@@ -4,8 +4,14 @@
 *.pyc
 .DS_Store
 .tox
+.idea
+.vscode
 MANIFEST
 build
 dist
 /tests/media/*
-!/tests/media/lenna.png
+!/tests/media/reference.png
+/venv
+/venv3
+/.env
+/tags

.travis.yml

@@ -1,7 +1,35 @@
+sudo: false
+
 language: python
 python:
-  - 2.7
-install: pip install tox --use-mirrors
-script: tox
+  - "3.8"
+  - "3.7"
+  - "3.6"
+  - "3.5"
+env:
+  - DJANGO="master"
+  - DJANGO="30"
+  - DJANGO="22"
+  - DJANGO="21"
+  - DJANGO="21"
+  - DJANGO="20"
+  - DJANGO="111"
+
+install:
+  - pip install tox
+
+script:
+  - tox -e py$(python -c 'import sys;print("".join(map(str, sys.version_info[:2])))')-django${DJANGO}
+
+jobs:
+  fast_finish: true
+  allow_failures:
+    - env: DJANGO="master"
+  exclude:
+    - python: "3.5"
+      env: DJANGO="30"
+    - python: "3.5"
+      env: DJANGO="master"
+
 notifications:
   irc: "irc.freenode.org#imagekit"

AUTHORS

@@ -6,8 +6,8 @@ HZDG_.
 Maintainers
 -----------
 
-* `Bryan Veloso`_
 * `Matthew Tretter`_
+* `Bryan Veloso`_
 * `Chris Drackett`_
 * `Greg Newman`_
 
@@ -26,6 +26,9 @@ Contributors
 * `Jan Sagemüller`_
 * `Clay McClure`_
 * `Jannis Leidel`_
+* `Sean Bell`_
+* `Saul Shanabrook`_
+* `Venelin Stoykov`_
 
 .. _Justin Driscoll: http://github.com/jdriscoll
 .. _HZDG: http://hzdg.com
@@ -45,3 +48,6 @@ Contributors
 .. _Jan Sagemüller: https://github.com/version2
 .. _Clay McClure: https://github.com/claymation
 .. _Jannis Leidel: https://github.com/jezdez
+.. _Sean Bell: https://github.com/seanbell
+.. _Saul Shanabrook: https://github.com/saulshanabrook
+.. _Venelin Stoykov: https://github.com/vstoykov

CONTRIBUTING.rst

@@ -8,7 +8,7 @@ contributions merged as quickly as possible:
 2. If you want to add a new feature, talk to us on the `mailing list`__ or
    `IRC`__ first. We might already have plans, or be able to offer some advice.
 3. Make sure your code passes the tests that ImageKit already has. To run the
-   tests, use ``make test``. This will let you know about any errors or style
+   tests, first install tox, ``pip install tox``, then use ``tox``. This will let you know about any errors or style
    issues.
 4. While we're talking about tests, creating new ones for your code makes it
    much easier for us to merge your code quickly. ImageKit uses nose_, so
@@ -21,4 +21,4 @@ __ http://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html
 __ https://groups.google.com/forum/#!forum/django-imagekit
 __ irc://irc.freenode.net/imagekit
 .. _nose: https://nose.readthedocs.org/en/latest/
-__ https://github.com/jdriscoll/django-imagekit/tree/develop/tests
+__ https://github.com/matthewwithanm/django-imagekit/tree/develop/tests

MANIFEST.in

@@ -1,5 +1,18 @@
 include AUTHORS
 include LICENSE
 include README.rst
-recursive-include docs *
-recursive-include imagekit/templates *
+include testrunner.py
+include setup.cfg
+include tests/*.py
+include tests/assets/Lenna.png
+include tests/assets/lenna-*.jpg
+include tests/media/lenna.png
+prune tests/media/CACHE
+prune tests/media/b
+prune tests/media/photos
+include docs/Makefile
+include docs/conf.py
+include docs/make.bat
+include docs/*.rst
+recursive-include docs/_themes LICENSE README.rst flask_theme_support.py theme.conf *.css_t *.css *.html
+recursive-include imagekit/templates *.html

README.rst

@@ -1,13 +1,22 @@
+|Build Status|_
+
+.. |Build Status| image:: https://travis-ci.org/matthewwithanm/django-imagekit.svg?branch=develop
+.. _Build Status: https://travis-ci.org/matthewwithanm/django-imagekit
+
 ImageKit is a Django app for processing images. Need a thumbnail? A
 black-and-white version of a user-uploaded image? ImageKit will make them for
 you. If you need to programatically generate one image from another, you need
 ImageKit.
 
+ImageKit comes with a bunch of image processors for common tasks like resizing
+and cropping, but you can also create your own. For an idea of what's possible,
+check out the `Instakit`__ project.
+
 **For the complete documentation on the latest stable version of ImageKit, see**
-`ImageKit on RTD`_. Our `changelog is also available`_.
+`ImageKit on RTD`_.
 
 .. _`ImageKit on RTD`: http://django-imagekit.readthedocs.org
-.. _`changelog is also available`: http://django-imagekit.readthedocs.org/en/latest/changelog.html
+__ https://github.com/fish2000/instakit
 
 
 Installation
@@ -16,7 +25,6 @@ Installation
 1. Install `PIL`_ or `Pillow`_. (If you're using an ``ImageField`` in Django,
    you should have already done this.)
 2. ``pip install django-imagekit``
-   (or clone the source and put the imagekit module on your path)
 3. Add ``'imagekit'`` to your ``INSTALLED_APPS`` list in your project's settings.py
 
 .. note:: If you've never seen Pillow before, it considers itself a
@@ -31,6 +39,7 @@ Installation
 Usage Overview
 ==============
 
+.. _specs:
 
 Specs
 -----
@@ -62,8 +71,8 @@ your model class:
                                           options={'quality': 60})
 
     profile = Profile.objects.all()[0]
-    print profile.avatar_thumbnail.url    # > /media/CACHE/images/982d5af84cddddfd0fbf70892b4431e4.jpg
-    print profile.avatar_thumbnail.width  # > 100
+    print(profile.avatar_thumbnail.url)    # > /media/CACHE/images/982d5af84cddddfd0fbf70892b4431e4.jpg
+    print(profile.avatar_thumbnail.width)  # > 100
 
 As you can probably tell, ImageSpecFields work a lot like Django's
 ImageFields. The difference is that they're automatically generated by
@@ -80,6 +89,7 @@ class:
 
     from django.db import models
     from imagekit.models import ProcessedImageField
+    from imagekit.processors import ResizeToFill
 
     class Profile(models.Model):
         avatar_thumbnail = ProcessedImageField(upload_to='avatars',
@@ -88,8 +98,8 @@ class:
                                                options={'quality': 60})
 
     profile = Profile.objects.all()[0]
-    print profile.avatar_thumbnail.url    # > /media/avatars/MY-avatar.jpg
-    print profile.avatar_thumbnail.width  # > 100
+    print(profile.avatar_thumbnail.url)    # > /media/avatars/MY-avatar.jpg
+    print(profile.avatar_thumbnail.width)  # > 100
 
 This is pretty similar to our previous example. We don't need to specify a
 "source" any more since we're not processing another image field, but we do need
@@ -128,24 +138,29 @@ particularly when the processing being done depends on user input.
         format = 'JPEG'
         options = {'quality': 60}
 
-It's probaby not surprising that this class is capable of processing an image
+It's probably not surprising that this class is capable of processing an image
 in the exact same way as our ImageSpecField above. However, unlike with the
 image spec model field, this class doesn't define what source the spec is acting
 on, or what should be done with the result; that's up to you:
 
 .. code-block:: python
 
-    source_file = open('/path/to/myimage.jpg')
+    source_file = open('/path/to/myimage.jpg', 'rb')
     image_generator = Thumbnail(source=source_file)
     result = image_generator.generate()
 
+.. note::
+
+    You don't have to use ``open``! You can use whatever File-like object you
+    want—including a model's ``ImageField``.
+
 The result of calling ``generate()`` on an image spec is a file-like object
 containing our resized image, with which you can do whatever you want. For
 example, if you wanted to save it to disk:
 
 .. code-block:: python
 
-    dest = open('/path/to/dest.jpg', 'w')
+    dest = open('/path/to/dest.jpg', 'wb')
     dest.write(result.read())
     dest.close()
 
@@ -172,7 +187,7 @@ to register it.
 
 .. code-block:: python
 
-    from imagekit import ImageSpec
+    from imagekit import ImageSpec, register
     from imagekit.processors import ResizeToFill
 
     class Thumbnail(ImageSpec):
@@ -215,7 +230,7 @@ that's what we need to pass to use our thumbnail spec:
 
     {% load imagekit %}
 
-    {% generateimage 'myapp:thumbnail' source=source_image %}
+    {% generateimage 'myapp:thumbnail' source=source_file %}
 
 This will output the following HTML:
 
@@ -230,7 +245,7 @@ keyword args using two dashes:
 
     {% load imagekit %}
 
-    {% generateimage 'myapp:thumbnail' source=source_image -- alt="A picture of Me" id="mypicture" %}
+    {% generateimage 'myapp:thumbnail' source=source_file -- alt="A picture of Me" id="mypicture" %}
 
 Not generating HTML image tags? No problem. The tag also functions as an
 assignment tag, providing access to the underlying file object:
@@ -239,7 +254,7 @@ assignment tag, providing access to the underlying file object:
 
     {% load imagekit %}
 
-    {% generateimage 'myapp:thumbnail' source=source_image as th %}
+    {% generateimage 'myapp:thumbnail' source=source_file as th %}
     <a href="{{ th.url }}">Click to download a cool {{ th.width }} x {{ th.height }} image!</a>
 
 
@@ -253,7 +268,7 @@ template tag:
 
     {% load imagekit %}
 
-    {% thumbnail '100x50' source_image %}
+    {% thumbnail '100x50' source_file %}
 
 Like the generateimage tag, the thumbnail tag outputs an <img> tag:
 
@@ -274,15 +289,15 @@ with the id "imagekit:thumbnail" which, by default, is
 Second, we're passing two positional arguments (the dimensions and the source
 image) as opposed to the keyword arguments we used with the generateimage tag.
 
-Like with the generatethumbnail tag, you can also specify additional HTML
-attributes for the thumbnail tag, or use it as an assignment tag:
+Like with the generateimage tag, you can also specify additional HTML attributes
+for the thumbnail tag, or use it as an assignment tag:
 
 .. code-block:: html
 
     {% load imagekit %}
 
-    {% thumbnail '100x50' source_image -- alt="A picture of Me" id="mypicture" %}
-    {% thumbnail '100x50' source_image as th %}
+    {% thumbnail '100x50' source_file -- alt="A picture of Me" id="mypicture" %}
+    {% thumbnail '100x50' source_file as th %}
 
 
 Using Specs in Forms
@@ -365,6 +380,12 @@ it in your spec's ``processors`` list:
         format = 'JPEG'
         options = {'quality': 60}
 
+Note that when you import a processor from ``imagekit.processors``, imagekit
+in turn imports the processor from `PILKit`_. So if you are looking for
+available processors, look at PILKit.
+
+.. _`PILKit`: https://github.com/matthewwithanm/pilkit
+
 
 Admin
 -----
@@ -386,6 +407,37 @@ Django admin classes:
 
     admin.site.register(Photo, PhotoAdmin)
 
+To use specs defined outside of models:
+
+.. code-block:: python
+    
+    from django.contrib import admin
+    from imagekit.admin import AdminThumbnail
+    from imagekit import ImageSpec
+    from imagekit.processors import ResizeToFill
+    from imagekit.cachefiles import ImageCacheFile
+
+    from .models import Photo
+
+    class AdminThumbnailSpec(ImageSpec):
+        processors = [ResizeToFill(100, 30)]
+        format = 'JPEG'
+        options = {'quality': 60 }
+
+    def cached_admin_thumb(instance):
+        # `image` is the name of the image field on the model
+        cached = ImageCacheFile(AdminThumbnailSpec(instance.image))
+        # only generates the first time, subsequent calls use cache
+        cached.generate()
+        return cached
+
+    class PhotoAdmin(admin.ModelAdmin):
+        list_display = ('__str__', 'admin_thumbnail')
+        admin_thumbnail = AdminThumbnail(image_field=cached_admin_thumb)
+
+    admin.site.register(Photo, PhotoAdmin)
+
+ 
 AdminThumbnail can even use a custom template. For more information, see
 ``imagekit.admin.AdminThumbnail``.
 
@@ -403,7 +455,7 @@ of generator ids in order to generate images selectively.
 Community
 =========
 
-Please use `the GitHub issue tracker <https://github.com/jdriscoll/django-imagekit/issues>`_
+Please use `the GitHub issue tracker <https://github.com/matthewwithanm/django-imagekit/issues>`_
 to report bugs with django-imagekit. `A mailing list <https://groups.google.com/forum/#!forum/django-imagekit>`_
 also exists to discuss the project and ask questions, as well as the official
 `#imagekit <irc://irc.freenode.net/imagekit>`_ channel on Freenode.
@@ -425,5 +477,5 @@ Check out our `contributing guidelines`__ for more information about pitching in
 with ImageKit.
 
 
-__ https://github.com/jdriscoll/django-imagekit/issues?labels=contributor-friendly&state=open
-__ https://github.com/jdriscoll/django-imagekit/blob/master/CONTRIBUTING.rst
+__ https://github.com/matthewwithanm/django-imagekit/issues?labels=contributor-friendly&state=open
+__ https://github.com/matthewwithanm/django-imagekit/blob/develop/CONTRIBUTING.rst

docs/advanced_usage.rst

@@ -47,14 +47,13 @@ for creating an ``ImageSpec``, registering it, and associating it with an
     class Profile(models.Model):
         avatar = models.ImageField(upload_to='avatars')
         avatar_thumbnail = ImageSpecField(source='avatar',
-                                          spec_id='myapp:profile:avatar_thumbnail')
+                                          id='myapp:profile:avatar_thumbnail')
 
 Obviously, the shorthand version is a lot, well…shorter. So why would you ever
 want to go through the trouble of using the long form? The answer is that the
 long form—creating an image spec class and registering it—gives you a lot more
 power over the generated image.
 
-
 .. _dynamic-specs:
 
 Specs That Change
@@ -98,7 +97,7 @@ for getting this information.
     class Profile(models.Model):
         avatar = models.ImageField(upload_to='avatars')
         avatar_thumbnail = ImageSpecField(source='avatar',
-                                          spec_id='myapp:profile:avatar_thumbnail')
+                                          id='myapp:profile:avatar_thumbnail')
         thumbnail_width = models.PositiveIntegerField()
         thumbnail_height = models.PositiveIntegerField()
 
@@ -109,107 +108,6 @@ Of course, processors aren't the only thing that can vary based on the model of
 the source image; spec behavior can change in any way you want.
 
 
-Optimizing
-==========
-
-Unlike Django's ImageFields, ImageKit's ImageSpecFields and template tags don't
-persist any data in the database. Therefore, in order to know whether an image
-file needs to be generated, ImageKit needs to check if the file already exists
-(using the appropriate file storage object`__). The object responsible for
-performing these checks is called a *cache file backend*.
-
-
-Cache!
-------
-
-By default, ImageKit checks for the existence of a cache file every time you
-attempt to use the file and, if it doesn't exist, creates it synchronously. This
-is a very safe behavior because it ensures that your ImageKit-generated images
-are always available. However, that's a lot of checking with storage and those
-kinds of operations can be slow—especially if you're using a remote storage—so
-you'll want to try to avoid them as much as possible.
-
-Luckily, the default cache file backend makes use of Django's caching
-abilities to mitigate the number of checks it actually has to do; it will use
-the cache specified by the ``IMAGEKIT_CACHE_BACKEND`` to save the state of the
-generated file. If your Django project is running in debug mode
-(``settings.DEBUG`` is true), this will be a dummy cache by default. Otherwise,
-it will use your project's default cache.
-
-In normal operation, your cache files will never be deleted; once they're
-created, they'll stay created. So the simplest optimization you can make is to
-set your ``IMAGEKIT_CACHE_BACKEND`` to a cache with a very long, or infinite,
-timeout.
-
-
-Even More Advanced
-------------------
-
-For many applications—particularly those using local storage for generated image
-files—a cache with a long timeout is all the optimization you'll need. However,
-there may be times when that simply doesn't cut it. In these cases, you'll want
-to change when the generation is actually done.
-
-The objects responsible for specifying when cache files are created are
-called *cache file strategies*. The default strategy can be set using the
-``IMAGEKIT_DEFAULT_CACHEFILE_STRATEGY`` setting, and its default value is
-`'imagekit.cachefiles.strategies.JustInTime'`. As we've already seen above,
-the "just in time" strategy determines whether a file needs to be generated each
-time it's accessed and, if it does, generates it synchronously (that is, as part
-of the request-response cycle).
-
-Another strategy is to simply assume the file exists. This requires the fewest
-number of checks (zero!), so we don't have to worry about expensive IO. The
-strategy that takes this approach is
-``imagekit.cachefiles.strategies.Optimistic``. In order to use this
-strategy, either set the ``IMAGEKIT_DEFAULT_CACHEFILE_STRATEGY`` setting or,
-to use it on a per-generator basis, set the ``cachefile_strategy`` attribute
-of your spec or generator. Avoiding checking for file existence can be a real
-boon to performance, but it also means that ImageKit has no way to know when a
-file needs to be generated—well, at least not all the time.
-
-With image specs, we can know at least some of the times that a new file needs
-to be generated: whenever the source image is created or changed. For this
-reason, the optimistic strategy defines callbacks for these events. Every
-source registered with ImageKit will automatically cause its specs' files to be
-generated when it is created or changed.
-
-.. note::
-
-    In order to understand source registration, read :ref:`source-groups`
-
-If you have specs that :ref:`change based on attributes of the source
-<dynamic-specs>`, that's not going to cut it, though; the file will also need to
-be generated when those attributes change. Likewise, image generators that don't
-have sources (i.e. generators that aren't specs) won't cause files to be
-generated automatically when using the optimistic strategy. (ImageKit can't know
-when those need to be generated, if not on access.) In both cases, you'll have
-to trigger the file generation yourself—either by generating the file in code
-when necessary, or by periodically running the ``generateimages`` management
-command. Luckily, ImageKit makes this pretty easy:
-
-.. code-block:: python
-
-    from imagekit.cachefiles import LazyImageCacheFile
-
-    file = LazyImageCacheFile('myapp:profile:avatar_thumbnail', source=source_file)
-    file.generate()
-
-One final situation in which images won't be generated automatically when using
-the optimistic strategy is when you use a spec with a source that hasn't been
-registered with it. Unlike the previous two examples, this situation cannot be
-rectified by running the ``generateimages`` management command, for the simple
-reason that the command has no way of knowing it needs to generate a file for
-that spec from that source. Typically, this situation would arise when using the
-template tags. Unlike ImageSpecFields, which automatically register all the
-possible source images with the spec you define, the template tags
-("generateimage" and "thumbnail") let you use any spec with any source.
-Therefore, in order to generate the appropriate files using the
-``generateimages`` management command, you'll need to first register a source
-group that represents all of the sources you wish to use with the corresponding
-specs. See :ref:`source-groups` for more information.
-
-
 .. _source-groups:
 
 Source Groups
@@ -224,7 +122,7 @@ The answer is that, when you define an ImageSpecField, ImageKit automatically
 creates and registers an object called a *source group*. Source groups are
 responsible for two things:
 
-1. They dispatch signals when a source is created, changed, or deleted, and
+1. They dispatch signals when a source is saved, and
 2. They expose a generator method that enumerates source files.
 
 When these objects are registered (using ``imagekit.register.source_group()``),
@@ -265,7 +163,7 @@ A simple example of a custom source group class is as follows:
         def files(self):
             os.chdir(self.dir)
             for name in glob.glob('*.jpg'):
-                yield open(name)
+                yield open(name, 'rb')
 
 Instances of this class could then be registered with one or more spec id:
 
@@ -279,6 +177,6 @@ Running the "generateimages" management command would now cause thumbnails to be
 generated (using the "myapp:profile:avatar_thumbnail" spec) for each of the
 JPEGs in `/path/to/some/pics`.
 
-Note that, since this source group doesnt send the `source_created` or
-`source_changed` signals, the corresponding cache file strategy callbacks
-would not be called for them.
+Note that, since this source group doesnt send the `source_saved` signal, the
+corresponding cache file strategy callbacks would not be called for them.
+

docs/caching.rst

@@ -0,0 +1,256 @@
+Caching
+*******
+
+
+Default Backend Workflow
+========================
+
+
+``ImageSpec``
+-------------
+
+At the heart of ImageKit are image generators. These are classes with a
+``generate()`` method which returns an image file. An image spec is a type of
+image generator. The thing that makes specs special is that they accept a source
+image. So an image spec is just an image generator that makes an image from some
+other image.
+
+
+``ImageCacheFile``
+------------------
+
+However, an image spec by itself would be vastly inefficient. Every time an
+an image was accessed in some way, it would have be regenerated and saved.
+Most of the time, you want to re-use a previously generated image, based on the
+input image and spec, instead of generating a new one. That's where
+``ImageCacheFile`` comes in. ``ImageCacheFile`` is a File-like object that
+wraps an image generator. They look and feel just like regular file
+objects, but they've got a little trick up their sleeve: they represent files
+that may not actually exist!
+
+
+.. _cache-file-strategy:
+
+Cache File Strategy
+-------------------
+
+Each ``ImageCacheFile`` has a cache file strategy, which abstracts away when
+image is actually generated. It can implement the following three methods:
+
+* ``on_content_required`` - called by ``ImageCacheFile`` when it requires the
+  contents of the generated image. For example, when you call ``read()`` or
+  try to access information contained in the file.
+* ``on_existence_required`` - called by ``ImageCacheFile`` when it requires the
+  generated image to exist but may not be concerned with its contents. For
+  example, when you access its ``url`` or ``path`` attribute.
+* ``on_source_saved`` - called when the source of a spec is saved
+
+The default strategy only defines the first two of these, as follows:
+
+.. code-block:: python
+
+    class JustInTime(object):
+        def on_content_required(self, file):
+            file.generate()
+
+        def on_existence_required(self, file):
+            file.generate()
+
+
+.. _cache-file-backend:
+
+Cache File Backend
+------------------
+
+The ``generate`` method on the ``ImageCacheFile`` is further delegated to the
+cache file backend, which abstracts away how an image is generated.
+
+The cache file backend defaults to the setting
+``IMAGEKIT_DEFAULT_CACHEFILE_BACKEND`` and can be set explicitly on a spec with
+the ``cachefile_backend`` attribute.
+
+The default works like this:
+
+* Checks the file storage to see if a file exists
+    * If not, caches that information for 5 seconds
+    * If it does, caches that information in the ``IMAGEKIT_CACHE_BACKEND``
+
+If file doesn't exist, generates it immediately and synchronously
+
+
+That pretty much covers the architecture of the caching layer, and its default
+behavior. I like the default behavior. When will an image be regenerated?
+Whenever it needs to be! When will your storage backend get hit? Depending on
+your ``IMAGEKIT_CACHE_BACKEND`` settings, as little as twice per file (once for the
+existence check and once to save the generated file). What if you want to change
+a spec? The generated file name (which is used as part of the cache keys) vary
+with the source file name and spec attributes, so if you change any of those, a
+new file will be generated. The default behavior is easy!
+
+.. note::
+
+    Like regular Django ImageFields, IK doesn't currently cache width and height
+    values, so accessing those will always result in a read. That will probably
+    change soon though.
+
+
+Optimizing
+==========
+
+There are several ways to improve the performance (reduce I/O operations) of
+ImageKit. Each has its own pros and cons.
+
+
+Caching Data About Generated Files
+----------------------------------
+
+Generally, once a file is generated, you will never be removing it, so by
+default ImageKit will use default cache to cache the state of generated
+files "forever" (or only 5 minutes when ``DEBUG = True``).
+
+The time for which ImageKit will cache state is configured with
+``IMAGEKIT_CACHE_TIMEOUT``. If set to ``None`` this means "never expire"
+(default when ``DEBUG = False``). You can reduce this timeout if you want
+or set it to some numeric value in seconds if your cache backend behaves
+differently and for example do not cache values if timeout is ``None``.
+
+If you clear your cache durring deployment or some other reason probably
+you do not want to lose the cache for generated images especcialy if you
+are using some slow remote storage (like Amazon S3). Then you can configure
+seprate cache (for example redis) in your ``CACHES`` config and tell ImageKit
+to use it instead of the default cache by setting ``IMAGEKIT_CACHE_BACKEND``.
+
+
+Pre-Generating Images
+---------------------
+
+The default cache file backend generates images immediately and synchronously.
+If you don't do anything special, that will be when they are first requested—as
+part of request-response cycle. This means that the first visitor to your page
+will have to wait for the file to be created before they see any HTML.
+
+This can be mitigated, though, by simply generating the images ahead of time, by
+running the ``generateimages`` management command.
+
+.. note::
+
+    If using with template tags, be sure to read :ref:`source-groups`.
+
+
+Deferring Image Generation
+--------------------------
+
+As mentioned above, image generation is normally done synchronously. through
+the default cache file backend. However, you can also take advantage of
+deferred generation. In order to do this, you'll need to do two things:
+
+1) install `celery`__ (or `django-celery`__ if you are bound to Celery<3.1)
+2) tell ImageKit to use the async cachefile backend.
+   To do this for all specs, set the ``IMAGEKIT_DEFAULT_CACHEFILE_BACKEND`` in
+   your settings
+
+.. code-block:: python
+
+    IMAGEKIT_DEFAULT_CACHEFILE_BACKEND = 'imagekit.cachefiles.backends.Async'
+
+Images will now be generated asynchronously. But watch out! Asynchrounous
+generation means you'll have to account for images that haven't been generated
+yet. You can do this by checking the truthiness of your files; if an image
+hasn't been generated, it will be falsy:
+
+.. code-block:: html
+
+    {% if not profile.avatar_thumbnail %}
+        <img src="/path/to/placeholder.jpg" />
+    {% else %}
+        <img src="{{ profile.avatar_thumbnail.url }}" />
+    {% endif %}
+
+Or, in Python:
+
+.. code-block:: python
+
+    profile = Profile.objects.all()[0]
+    if profile.avatar_thumbnail:
+        url = profile.avatar_thumbnail.url
+    else:
+        url = '/path/to/placeholder.jpg'
+
+.. note::
+
+    If you are using an "async" backend in combination with the "optimistic"
+    cache file strategy (see `Removing Safeguards`_ below), checking for
+    thruthiness as described above will not work. The "optimistic" backend is
+    very optimistic so to say, and removes the check. Create and use the
+    following strategy to a) have images only created on save, and b) retain
+    the ability to check whether the images have already been created::
+
+        class ImagekitOnSaveStrategy(object):
+            def on_source_saved(self, file):
+                file.generate()
+
+.. note::
+
+    If you use custom storage backend for some specs,
+    (storage passed to the field different than configured one)
+    it's required the storage to be pickleable
+
+
+__ https://pypi.python.org/pypi/django-celery
+__ http://www.celeryproject.org
+
+
+Removing Safeguards
+-------------------
+
+Even with pre-generating images, ImageKit will still try to ensure that your
+image exists when you access it by default. This is for your benefit: if you
+forget to generate your images, ImageKit will see that and generate it for you.
+If the state of the file is cached (see above), this is a pretty cheap
+operation. However, if the state isn't cached, ImageKit will need to query the
+storage backend.
+
+For those who aren't willing to accept that cost (and who never want ImageKit
+to generate images in the request-responce cycle), there's the "optimistic"
+cache file strategy. This strategy only generates a new image when a spec's
+source image is created or changed. Unlike with the "just in time" strategy,
+accessing the file won't cause it to be generated, ImageKit will just assume
+that it already exists.
+
+To use this cache file strategy for all specs, set the
+``IMAGEKIT_DEFAULT_CACHEFILE_STRATEGY`` in your settings:
+
+.. code-block:: python
+
+    IMAGEKIT_DEFAULT_CACHEFILE_STRATEGY = 'imagekit.cachefiles.strategies.Optimistic'
+
+If you have specs that :ref:`change based on attributes of the source
+<dynamic-specs>`, that's not going to cut it, though; the file will also need to
+be generated when those attributes change. Likewise, image generators that don't
+have sources (i.e. generators that aren't specs) won't cause files to be
+generated automatically when using the optimistic strategy. (ImageKit can't know
+when those need to be generated, if not on access.) In both cases, you'll have
+to trigger the file generation yourself—either by generating the file in code
+when necessary, or by periodically running the ``generateimages`` management
+command. Luckily, ImageKit makes this pretty easy:
+
+.. code-block:: python
+
+    from imagekit.cachefiles import LazyImageCacheFile
+
+    file = LazyImageCacheFile('myapp:profile:avatar_thumbnail', source=source_file)
+    file.generate()
+
+One final situation in which images won't be generated automatically when using
+the optimistic strategy is when you use a spec with a source that hasn't been
+registered with it. Unlike the previous two examples, this situation cannot be
+rectified by running the ``generateimages`` management command, for the simple
+reason that the command has no way of knowing it needs to generate a file for
+that spec from that source. Typically, this situation would arise when using the
+template tags. Unlike ImageSpecFields, which automatically register all the
+possible source images with the spec you define, the template tags
+("generateimage" and "thumbnail") let you use any spec with any source.
+Therefore, in order to generate the appropriate files using the
+``generateimages`` management command, you'll need to first register a source
+group that represents all of the sources you wish to use with the corresponding
+specs. See :ref:`source-groups` for more information.

docs/changelog.rst

@@ -1,142 +0,0 @@
-Changelog
-=========
-
-v2.0.2
-------
-
-- Fixed the pickling of ImageSpecFieldFile.
-- Signals are now connected without specifying the class and non-IK models
-  are filitered out in the receivers. This is necessary beacuse of a bug
-  with how Django handles abstract models.
-- Fixed a `ZeroDivisionError` in the Reflection processor.
-- `cStringIO` is now used if it's available.
-- Reflections on images now use RGBA instead of RGB.
-
-v2.0.1
-------
-
-- Fixed a file descriptor leak in the `utils.quiet()` context manager.
-
-
-v2.0.0
-------
-
-- Added the concept of image cache backends. Image cache backends assume
-  control of validating and invalidating the cached images from `ImageSpec` in
-  versions past. The default backend maintins the current behavior: invalidating
-  an image deletes it, while validating checks whether the file exists and
-  creates the file if it doesn't. One can create custom image cache backends to
-  control how their images are cached (e.g., Celery, etc.).
-
-  ImageKit ships with three built-in backends:
-
-  - ``imagekit.imagecache.PessimisticImageCacheBackend`` - A very safe image
-    cache backend. Guarantees that files will always be available, but at the
-    cost of hitting the storage backend.
-  - ``imagekit.imagecache.NonValidatingImageCacheBackend`` - A backend that is
-    super optimistic about the existence of spec files. It will hit your file
-    storage much less frequently than the pessimistic backend, but it is
-    technically possible for a cache file to be missing after validation.
-  - ``imagekit.imagecache.celery.CeleryImageCacheBackend`` - A pessimistic cache
-    state backend that uses celery to generate its spec images. Like
-    ``PessimisticCacheStateBackend``, this one checks to see if the file
-    exists on validation, so the storage is hit fairly frequently, but an
-    image is guaranteed to exist. However, while validation guarantees the
-    existence of *an* image, it does not necessarily guarantee that you will
-    get the correct image, as the spec may be pending regeneration. In other
-    words, while there are ``generate`` tasks in the queue, it is possible to
-    get a stale spec image. The tradeoff is that calling ``invalidate()``
-    won't block to interact with file storage.
-
-- Some of the processors have been renamed and several new ones have been added:
-
-  - ``imagekit.processors.ResizeToFill`` - (previously
-    ``imagekit.processors.resize.Crop``) Scales the image to fill the provided
-    dimensions and then trims away the excess.
-  - ``imagekit.processors.ResizeToFit`` - (previously
-    ``imagekit.processors.resize.Fit``) Scale to fit the provided dimensions.
-  - ``imagekit.processors.SmartResize`` - Like ``ResizeToFill``, but crops using
-    entroy (``SmartCrop``) instead of an anchor argument.
-  - ``imagekit.processors.BasicCrop`` - Crop using provided box.
-  - ``imagekit.processors.SmartCrop`` - (previously
-    ``imagekit.processors.resize.SmartCrop``) Crop to provided size, trimming
-    based on entropy.
-  - ``imagekit.processors.TrimBorderColor`` - Trim the specified color from the
-    specified sides.
-  - ``imagekit.processors.AddBorder`` - Add a border of specific color and
-    thickness to an image.
-  - ``imagekit.processors.Resize`` - Scale to the provided dimensions (can distort).
-  - ``imagekit.processors.ResizeToCover`` - Scale to the smallest size that will
-    cover the specified dimensions. Used internally by ``Fill`` and
-    ``SmartFill``.
-  - ``imagekit.processors.ResizeCanvas`` - Takes an image an resizes the canvas,
-    using a specific background color if the new size is larger than the current
-    image.
-
-- ``mat_color`` has been added as an arguemnt to ``ResizeToFit``. If set, the
-  the target image size will be enforced and the specified color will be
-  used as background color to pad the image.
-
-- We now use `Tox`_ to automate testing.
-
-.. _`Tox`: http://pypi.python.org/pypi/tox
-
-
-v1.1.0
-------
-
-- A ``SmartCrop`` resize processor was added. This allows an image to be
-  cropped based on the amount of entropy in the target image's histogram.
-
-- The ``quality`` argument was removed in favor of an ``options`` dictionary.
-  This is a more general solution which grants access to PIL's format-specific
-  options (including "quality", "progressive", and "optimize" for JPEGs).
-
-- The ``TrimColor`` processor was renamed to ``TrimBorderColor``.
-
-- The private ``_Resize`` class has been removed.
-
-
-v1.0.3
-------
-
-- ``ImageSpec._create()`` was renamed ``ImageSpec.generate()`` and is now
-  available in the public API.
-
-- Added an ``AutoConvert`` processor to encapsulate the transparency
-  handling logic.
-
-- Refactored transparency handling to be smarter, handling a lot more of
-  the situations in which one would convert to or from formats that support
-  transparency.
-
-- Fixed PIL zeroing out files when write mode is enabled.
-
-
-v1.0.2
-------
-
-- Added this changelog.
-
-- Enhanced extension detection, format detection, and conversion between the
-  two. This eliminates the reliance on an image being loaded into memory
-  beforehand in order to detect said image's extension.
-
-- Fixed a regression from the 0.4.x series in which ImageKit was unable to
-  convert a PNG file in ``P`` or "palette" mode to JPEG.
-
-
-v1.0.1
-------
-
-- Minor fixes related to the rendering of ``README.rst`` as a reStructured
-  text file.
-
-- Fixed the included admin template not being found when ImageKit was  and
-  the packaging of the included admin templates.
-
-
-v1.0
-----
-
-- Initial release of the *new* field-based ImageKit API.

docs/conf.py

@@ -54,7 +54,7 @@ execfile(os.path.join(os.path.dirname(__file__), '..', 'imagekit',
 # built documents.
 #
 # The short X.Y version.
-version = re.match('\d+\.\d+', pkgmeta['__version__']).group()
+version = re.match(r'\d+\.\d+', pkgmeta['__version__']).group()
 # The full version, including alpha/beta/rc tags.
 release = pkgmeta['__version__']
 

docs/configuration.rst

@@ -23,7 +23,7 @@ Settings
 
     The qualified class name of a Django storage backend to use to save the
     cached images. If no value is provided for ``IMAGEKIT_DEFAULT_FILE_STORAGE``,
-    and none is specified by the spec definition, the storage of the source file
+    and none is specified by the spec definition, `your default file storage`__
     will be used.
 
 
@@ -44,11 +44,24 @@ Settings
 
 .. attribute:: IMAGEKIT_CACHE_BACKEND
 
-    :default: If ``DEBUG`` is ``True``, ``'django.core.cache.backends.dummy.DummyCache'``.
-    Otherwise, ``'default'``.
+    :default:  ``'default'``
 
-    The Django cache backend to be used to store information like the state of
-    cached images (i.e. validated or not).
+    The Django cache backend alias to retrieve the shared cache instance defined
+    in your settings, as described in the `Django cache section`_.
+
+    The cache is then used to store information like the state of cached
+    images (i.e. validated or not).
+
+.. _`Django cache section`: https://docs.djangoproject.com/en/1.8/topics/cache/#accessing-the-cache
+
+
+.. attribute:: IMAGEKIT_CACHE_TIMEOUT
+
+    :default: ``None``
+
+    Use when you need to override the timeout used to cache file state.
+    By default it is "cache forever".
+    It's highly recommended that you use a very high timeout.
 
 
 .. attribute:: IMAGEKIT_CACHE_PREFIX
@@ -72,3 +85,6 @@ Settings
     A function responsible for generating file names for cache files that
     correspond to image specs. Since you will likely want to base the name of
     your cache files on the name of the source, this extra setting is provided.
+
+
+__ https://docs.djangoproject.com/en/dev/ref/settings/#default-file-storage

docs/index.rst

@@ -20,5 +20,5 @@ Indices and tables
 
     configuration
     advanced_usage
-    changelog
+    caching
     upgrading

docs/upgrading.rst

@@ -79,12 +79,9 @@ IK3 provides analogous settings for cache file backends and strategies:
     IMAGEKIT_DEFAULT_CACHEFILE_BACKEND = 'path.to.MyCacheFileBackend'
     IMAGEKIT_DEFAULT_CACHEFILE_STRATEGY = 'path.to.MyCacheFileStrategy'
 
-See the documentation on `cache file backends`_ and `cache file strategies`_
+See the documentation on :ref:`cache file backends <cache-file-backend>` and :ref:`cache file strategies <cache-file-strategy>`
 for more details.
 
-.. _`cache file backends`:
-.. _`cache file strategies`:
-
 
 Conditional model ``processors``
 --------------------------------
@@ -93,9 +90,7 @@ In IK2, an ``ImageSpecField`` could take a ``processors`` callable instead of
 an iterable, which allowed processing decisions to made based on other
 properties of the model. IK3 does away with this feature for consistency's sake
 (if one kwarg could be callable, why not all?), but provides a much more robust
-solution: the custom ``spec``. See the `advanced usage`_ documentation for more.
-
-.. _`advanced usage`:
+solution: the custom ``spec``. See the :doc:`advanced usage <advanced_usage>` documentation for more.
 
 
 Conditonal ``cache_to`` file names
@@ -109,6 +104,14 @@ There is a way to achieve custom file names by overriding your spec's
 ``cachefile_name``, but it is not recommended, as the spec's default
 behavior is to hash the combination of ``source``, ``processors``, ``format``,
 and other spec options to ensure that changes to the spec always result in
-unique file names. See the documentation on `specs`_ for more.
+unique file names. See the documentation on :ref:`specs` for more.
 
-.. _`specs`:
+
+Processors have moved to PILKit
+-------------------------------
+
+Processors have moved to a separate project: `PILKit`_. You should not have to
+make any changes to an IK2 project to use PILKit--it should be installed with
+IK3, and importing from ``imagekit.processors`` will still work.
+
+.. _`PILKit`: https://github.com/matthewwithanm/pilkit

imagekit/__init__.py

@@ -1,5 +1,4 @@
 # flake8: noqa
-from . import importers
 from . import conf
 from . import generatorlibrary
 from .specs import ImageSpec

imagekit/cachefiles/__init__.py

@@ -1,9 +1,12 @@
+from copy import copy
 from django.conf import settings
+from django.core.files import File
 from django.core.files.images import ImageFile
-from django.utils.functional import LazyObject
+from django.utils.functional import SimpleLazyObject
+from django.utils.encoding import smart_str
 from ..files import BaseIKFile
 from ..registry import generator_registry
-from ..signals import before_access
+from ..signals import content_required, existence_required
 from ..utils import get_logger, get_singleton, generate, get_by_qname
 
 
@@ -15,7 +18,7 @@ class ImageCacheFile(BaseIKFile, ImageFile):
     to be deferred until the time that the cache file strategy requires it.
 
     """
-    def __init__(self, generator, name=None, storage=None, cachefile_backend=None):
+    def __init__(self, generator, name=None, storage=None, cachefile_backend=None, cachefile_strategy=None):
         """
         :param generator: The object responsible for generating a new image.
         :param name: The filename
@@ -23,33 +26,72 @@ class ImageCacheFile(BaseIKFile, ImageFile):
             file.
         :param cachefile_backend: The object responsible for managing the
             state of the file.
+        :param cachefile_strategy: The object responsible for handling events
+            for this file.
 
         """
         self.generator = generator
 
-        name = name or getattr(generator, 'cachefile_name', None)
         if not name:
-            fn = get_by_qname(settings.IMAGEKIT_CACHEFILE_NAMER, 'namer')
-            name = fn(generator)
+            try:
+                name = generator.cachefile_name
+            except AttributeError:
+                fn = get_by_qname(settings.IMAGEKIT_CACHEFILE_NAMER, 'namer')
+                name = fn(generator)
         self.name = name
 
         storage = storage or getattr(generator, 'cachefile_storage',
             None) or get_singleton(settings.IMAGEKIT_DEFAULT_FILE_STORAGE,
             'file storage backend')
-        self.cachefile_backend = cachefile_backend or getattr(generator,
-            'cachefile_backend', None)
+        self.cachefile_backend = (
+            cachefile_backend
+            or getattr(generator, 'cachefile_backend', None)
+            or get_singleton(settings.IMAGEKIT_DEFAULT_CACHEFILE_BACKEND,
+                             'cache file backend'))
+        self.cachefile_strategy = (
+            cachefile_strategy
+            or getattr(generator, 'cachefile_strategy', None)
+            or get_singleton(settings.IMAGEKIT_DEFAULT_CACHEFILE_STRATEGY,
+                             'cache file strategy')
+        )
 
         super(ImageCacheFile, self).__init__(storage=storage)
 
     def _require_file(self):
-        before_access.send(sender=self, file=self)
-        return super(ImageCacheFile, self)._require_file()
+        if getattr(self, '_file', None) is None:
+            content_required.send(sender=self, file=self)
+            self._file = self.storage.open(self.name, 'rb')
+
+    # The ``path`` and ``url`` properties are overridden so as to not call
+    # ``_require_file``, which is only meant to be called when the file object
+    # will be directly interacted with (e.g. when using ``read()``). These only
+    # require the file to exist; they do not need its contents to work. This
+    # distinction gives the user the flexibility to create a cache file
+    # strategy that assumes the existence of a file, but can still make the file
+    # available when its contents are required.
+
+    def _storage_attr(self, attr):
+        if getattr(self, '_file', None) is None:
+            existence_required.send(sender=self, file=self)
+        fn = getattr(self.storage, attr)
+        return fn(self.name)
+
+    @property
+    def path(self):
+        return self._storage_attr('path')
+
+    @property
+    def url(self):
+        return self._storage_attr('url')
 
     def generate(self, force=False):
-        if force:
-            self._generate()
-        else:
-            self.cachefile_backend.ensure_exists(self)
+        """
+        Generate the file. If ``force`` is ``True``, the file will be generated
+        whether the file already exists or not.
+
+        """
+        if force or getattr(self, '_file', None) is None:
+            self.cachefile_backend.generate(self, force)
 
     def _generate(self):
         # Generate the file
@@ -57,39 +99,85 @@ class ImageCacheFile(BaseIKFile, ImageFile):
 
         actual_name = self.storage.save(self.name, content)
 
+        # We're going to reuse the generated file, so we need to reset the pointer.
+        content.seek(0)
+
+        # Store the generated file. If we don't do this, the next time the
+        # "file" attribute is accessed, it will result in a call to the storage
+        # backend (in ``BaseIKFile._get_file``). Since we already have the
+        # contents of the file, what would the point of that be?
+        self.file = File(content)
+
         if actual_name != self.name:
-            get_logger().warning('The storage backend %s did not save the file'
-                    ' with the requested name ("%s") and instead used'
-                    ' "%s". This may be because a file already existed with'
-                    ' the requested name. If so, you may have meant to call'
-                    ' ensure_exists() instead of generate(), or there may be a'
-                    ' race condition in the file backend %s. The saved file'
-                    ' will not be used.' % (self.storage,
+            get_logger().warning(
+                'The storage backend %s did not save the file with the'
+                ' requested name ("%s") and instead used "%s". This may be'
+                ' because a file already existed with the requested name. If'
+                ' so, you may have meant to call generate() instead of'
+                ' generate(force=True), or there may be a race condition in the'
+                ' file backend %s. The saved file will not be used.' % (
+                    self.storage,
                     self.name, actual_name,
-                    self.cachefile_backend))
+                    self.cachefile_backend
+                )
+            )
 
+    def __bool__(self):
+        if not self.name:
+            return False
 
-class LazyImageCacheFile(LazyObject):
-    def __init__(self, generator_id, *args, **kwargs):
-        super(LazyImageCacheFile, self).__init__()
+        # Dispatch the existence_required signal before checking to see if the
+        # file exists. This gives the strategy a chance to create the file.
+        existence_required.send(sender=self, file=self)
 
-        def setup():
-            generator = generator_registry.get(generator_id, *args, **kwargs)
-            self._wrapped = ImageCacheFile(generator)
+        try:
+            check = self.cachefile_strategy.should_verify_existence(self)
+        except AttributeError:
+            # All synchronous backends should have created the file as part of
+            # `existence_required` if they wanted to.
+            check = getattr(self.cachefile_backend, 'is_async', False)
+        return self.cachefile_backend.exists(self) if check else True
 
-        self.__dict__['_setup'] = setup
+    def __getstate__(self):
+        state = copy(self.__dict__)
+
+        # file is hidden link to "file" attribute
+        state.pop('_file', None)
+
+        # remove storage from state as some non-FileSystemStorage can't be
+        # pickled
+        settings_storage = get_singleton(
+            settings.IMAGEKIT_DEFAULT_FILE_STORAGE,
+            'file storage backend'
+        )
+        if state['storage'] == settings_storage:
+            state.pop('storage')
+        return state
+
+    def __setstate__(self, state):
+        if 'storage' not in state:
+            state['storage'] = get_singleton(
+                settings.IMAGEKIT_DEFAULT_FILE_STORAGE,
+                'file storage backend'
+            )
+        self.__dict__.update(state)
+
+    def __nonzero__(self):
+        # Python 2 compatibility
+        return self.__bool__()
 
     def __repr__(self):
-        if self._wrapped is None:
-            self._setup()
-        return '<%s: %s>' % (self.__class__.__name__, self or 'None')
+        return smart_str("<%s: %s>" % (
+            self.__class__.__name__, self if self.name else "None")
+        )
 
-    def __str__(self):
-        if self._wrapped is None:
-            self._setup()
-        return str(self._wrapped)
 
-    def __unicode__(self):
-        if self._wrapped is None:
-            self._setup()
-        return unicode(self._wrapped)
+class LazyImageCacheFile(SimpleLazyObject):
+    def __init__(self, generator_id, *args, **kwargs):
+        def setup():
+            generator = generator_registry.get(generator_id, *args, **kwargs)
+            return ImageCacheFile(generator)
+        super(LazyImageCacheFile, self).__init__(setup)
+
+    def __repr__(self):
+        return '<%s: %s>' % (self.__class__.__name__, str(self) or 'None')

imagekit/cachefiles/actions.py

@@ -1,22 +0,0 @@
-def generate(file):
-    file.generate()
-
-
-try:
-    from celery.task import task
-except ImportError:
-    pass
-else:
-    generate_task = task(generate)
-
-
-def generate_deferred(file):
-    try:
-        import celery  # NOQA
-    except:
-        raise ImportError("Deferred validation requires the the 'celery' library")
-    generate_task.delay(file)
-
-
-def clear_now(file):
-    file.clear()

imagekit/cachefiles/backends.py

@@ -1,6 +1,14 @@
-from ..utils import get_singleton
-from django.core.cache import get_cache
+from ..utils import get_singleton, get_cache, sanitize_cache_key
+import warnings
+from copy import copy
 from django.core.exceptions import ImproperlyConfigured
+from django.conf import settings
+
+
+class CacheFileState(object):
+    EXISTS = 'exists'
+    GENERATING = 'generating'
+    DOES_NOT_EXIST = 'does_not_exist'
 
 
 def get_default_cachefile_backend():
@@ -10,55 +18,178 @@ def get_default_cachefile_backend():
     """
     from django.conf import settings
     return get_singleton(settings.IMAGEKIT_DEFAULT_CACHEFILE_BACKEND,
-            'file backend')
+                         'file backend')
 
 
 class InvalidFileBackendError(ImproperlyConfigured):
     pass
 
 
+class AbstractCacheFileBackend(object):
+    """
+    An abstract cache file backend. This isn't used by any internal classes and
+    is included simply to illustrate the minimum interface of a cache file
+    backend for users who wish to implement their own.
+
+    """
+    def generate(self, file, force=False):
+        raise NotImplementedError
+
+    def exists(self, file):
+        raise NotImplementedError
+
+
 class CachedFileBackend(object):
+    existence_check_timeout = 5
+    """
+    The number of seconds to wait before rechecking to see if the file exists.
+    If the image is found to exist, that information will be cached using the
+    timeout specified in your CACHES setting (which should be very high).
+    However, when the file does not exist, you probably want to check again
+    in a relatively short amount of time. This attribute allows you to do that.
+
+    """
+
     @property
     def cache(self):
         if not getattr(self, '_cache', None):
-            from django.conf import settings
-            self._cache = get_cache(settings.IMAGEKIT_CACHE_BACKEND)
+            self._cache = get_cache()
         return self._cache
 
     def get_key(self, file):
         from django.conf import settings
-        return '%s%s-exists' % (settings.IMAGEKIT_CACHE_PREFIX, file.name)
+        return sanitize_cache_key('%s%s-state' %
+                                  (settings.IMAGEKIT_CACHE_PREFIX, file.name))
 
-    def file_exists(self, file):
+    def get_state(self, file, check_if_unknown=True):
         key = self.get_key(file)
-        exists = self.cache.get(key)
-        if exists is None:
-            exists = self._file_exists(file)
-            self.cache.set(key, exists)
-        return exists
+        state = self.cache.get(key)
+        if state is None and check_if_unknown:
+            exists = self._exists(file)
+            state = CacheFileState.EXISTS if exists else CacheFileState.DOES_NOT_EXIST
+            self.set_state(file, state)
+        return state
 
-    def ensure_exists(self, file):
-        if self.file_exists(file):
-            self.create(file)
-            self.cache.set(self.get_key(file), True)
+    def set_state(self, file, state):
+        key = self.get_key(file)
+        if state == CacheFileState.DOES_NOT_EXIST:
+            self.cache.set(key, state, self.existence_check_timeout)
+        else:
+            self.cache.set(key, state, settings.IMAGEKIT_CACHE_TIMEOUT)
+
+    def __getstate__(self):
+        state = copy(self.__dict__)
+        # Don't include the cache when pickling. It'll be reconstituted based
+        # on the settings.
+        state.pop('_cache', None)
+        return state
+
+    def exists(self, file):
+        return self.get_state(file) == CacheFileState.EXISTS
+
+    def generate(self, file, force=False):
+        raise NotImplementedError
+
+    def generate_now(self, file, force=False):
+        if force or self.get_state(file) not in (CacheFileState.GENERATING, CacheFileState.EXISTS):
+            self.set_state(file, CacheFileState.GENERATING)
+            file._generate()
+            self.set_state(file, CacheFileState.EXISTS)
+            file.close()
 
 
 class Simple(CachedFileBackend):
     """
     The most basic file backend. The storage is consulted to see if the file
-    exists.
+    exists. Files are generated synchronously.
 
     """
 
-    def _file_exists(self, file):
-        if not getattr(file, '_file', None):
-            # No file on object. Have to check storage.
-            return not file.storage.exists(file.name)
-        return False
+    def generate(self, file, force=False):
+        self.generate_now(file, force=force)
 
-    def create(self, file):
-        """
-        Generates a new image by running the processors on the source file.
+    def _exists(self, file):
+        return bool(getattr(file, '_file', None)
+                    or (file.name and file.storage.exists(file.name)))
 
-        """
-        file.generate(force=True)
+
+def _generate_file(backend, file, force=False):
+    backend.generate_now(file, force=force)
+
+
+class BaseAsync(Simple):
+    """
+    Base class for cache file backends that generate files asynchronously.
+    """
+    is_async = True
+
+    def generate(self, file, force=False):
+        # Schedule the file for generation, unless we know for sure we don't
+        # need to. If an already-generated file sneaks through, that's okay;
+        # ``generate_now`` will catch it. We just want to make sure we don't
+        # schedule anything we know is unnecessary--but we also don't want to
+        # force a costly existence check.
+        state = self.get_state(file, check_if_unknown=False)
+        if state not in (CacheFileState.GENERATING, CacheFileState.EXISTS):
+            self.schedule_generation(file, force=force)
+
+    def schedule_generation(self, file, force=False):
+        # overwrite this to have the file generated in the background,
+        # e. g. in a worker queue.
+        raise NotImplementedError
+
+
+try:
+    from celery import task
+except ImportError:
+    pass
+else:
+    _celery_task = task(ignore_result=True, serializer='pickle')(_generate_file)
+
+
+class Celery(BaseAsync):
+    """
+    A backend that uses Celery to generate the images.
+    """
+    def __init__(self, *args, **kwargs):
+        try:
+            import celery  # noqa
+        except ImportError:
+            raise ImproperlyConfigured('You must install celery to use'
+                                       ' imagekit.cachefiles.backends.Celery.')
+        super(Celery, self).__init__(*args, **kwargs)
+
+    def schedule_generation(self, file, force=False):
+        _celery_task.delay(self, file, force=force)
+
+
+# Stub class to preserve backwards compatibility and issue a warning
+class Async(Celery):
+    def __init__(self, *args, **kwargs):
+        message = '{path}.Async is deprecated. Use {path}.Celery instead.'
+        warnings.warn(message.format(path=__name__), DeprecationWarning)
+        super(Async, self).__init__(*args, **kwargs)
+
+
+try:
+    from django_rq import job
+except ImportError:
+    pass
+else:
+    _rq_job = job('default', result_ttl=0)(_generate_file)
+
+
+class RQ(BaseAsync):
+    """
+    A backend that uses RQ to generate the images.
+    """
+    def __init__(self, *args, **kwargs):
+        try:
+            import django_rq  # noqa
+        except ImportError:
+            raise ImproperlyConfigured('You must install django-rq to use'
+                                       ' imagekit.cachefiles.backends.RQ.')
+        super(RQ, self).__init__(*args, **kwargs)
+
+    def schedule_generation(self, file, force=False):
+        _rq_job.delay(self, file, force=force)

imagekit/cachefiles/strategies.py

@@ -1,4 +1,7 @@
+import six
+
 from django.utils.functional import LazyObject
+from ..lib import force_text
 from ..utils import get_singleton
 
 
@@ -8,7 +11,10 @@ class JustInTime(object):
 
     """
 
-    def before_access(self, file):
+    def on_existence_required(self, file):
+        file.generate()
+
+    def on_content_required(self, file):
         file.generate()
 
 
@@ -20,11 +26,11 @@ class Optimistic(object):
 
     """
 
-    def on_source_created(self, file):
+    def on_source_saved(self, file):
         file.generate()
 
-    def on_source_changed(self, file):
-        file.generate()
+    def should_verify_existence(self, file):
+        return False
 
 
 class DictStrategy(object):
@@ -33,24 +39,11 @@ class DictStrategy(object):
             setattr(self, k, v)
 
 
-class StrategyWrapper(LazyObject):
-    def __init__(self, strategy):
-        if isinstance(strategy, basestring):
-            strategy = get_singleton(strategy, 'cache file strategy')
-        elif isinstance(strategy, dict):
-            strategy = DictStrategy(strategy)
-        elif callable(strategy):
-            strategy = strategy()
-        self._wrapped = strategy
-
-    def __getstate__(self):
-        return {'_wrapped': self._wrapped}
-
-    def __setstate__(self, state):
-        self._wrapped = state['_wrapped']
-
-    def __unicode__(self):
-        return unicode(self._wrapped)
-
-    def __str__(self):
-        return str(self._wrapped)
+def load_strategy(strategy):
+    if isinstance(strategy, six.string_types):
+        strategy = get_singleton(strategy, 'cache file strategy')
+    elif isinstance(strategy, dict):
+        strategy = DictStrategy(strategy)
+    elif callable(strategy):
+        strategy = strategy()
+    return strategy

imagekit/conf.py

@@ -1,5 +1,6 @@
 from appconf import AppConf
 from django.conf import settings
+from django.core.exceptions import ImproperlyConfigured
 
 
 class ImageKitConf(AppConf):
@@ -9,15 +10,31 @@ class ImageKitConf(AppConf):
     DEFAULT_CACHEFILE_BACKEND = 'imagekit.cachefiles.backends.Simple'
     DEFAULT_CACHEFILE_STRATEGY = 'imagekit.cachefiles.strategies.JustInTime'
 
-    DEFAULT_FILE_STORAGE = 'django.core.files.storage.FileSystemStorage'
+    DEFAULT_FILE_STORAGE = None
 
     CACHE_BACKEND = None
     CACHE_PREFIX = 'imagekit:'
+    CACHE_TIMEOUT = None
+    USE_MEMCACHED_SAFE_CACHE_KEY = True
 
     def configure_cache_backend(self, value):
         if value is None:
-            if getattr(settings, 'CACHES', None):
-                value = 'django.core.cache.backends.dummy.DummyCache' if settings.DEBUG else 'default'
-            else:
-                value = 'dummy://' if settings.DEBUG else settings.CACHE_BACKEND
+            from django.core.cache import DEFAULT_CACHE_ALIAS
+            return DEFAULT_CACHE_ALIAS
+
+        if value not in settings.CACHES:
+            raise ImproperlyConfigured("{0} is not present in settings.CACHES".format(value))
+
+        return value
+
+    def configure_cache_timeout(self, value):
+        if value is None and settings.DEBUG:
+            # If value is not configured and is DEBUG set it to 5 minutes
+            return 300
+        # Otherwise leave it as is. If it is None then valies will never expire
+        return value
+
+    def configure_default_file_storage(self, value):
+        if value is None:
+            value = settings.DEFAULT_FILE_STORAGE
         return value

imagekit/exceptions.py

@@ -13,6 +13,10 @@ class MissingGeneratorId(Exception):
     pass
 
 
+class MissingSource(ValueError):
+    pass
+
+
 # Aliases for backwards compatibility
 UnknownExtensionError = UnknownExtension
 UnknownFormatError = UnknownFormat

imagekit/files.py

@@ -1,6 +1,9 @@
-from django.core.files.base import File, ContentFile
-from django.utils.encoding import smart_str, smart_unicode
+from __future__ import unicode_literals
 import os
+
+from django.core.files.base import File, ContentFile
+from django.utils.encoding import smart_str
+from .lib import smart_text
 from .utils import format_to_mimetype, extension_to_mimetype
 
 
@@ -46,14 +49,25 @@ class BaseIKFile(File):
 
     def _get_size(self):
         self._require_file()
-        if not self._committed:
+        if not getattr(self, '_committed', False):
             return self.file.size
         return self.storage.size(self.name)
     size = property(_get_size)
 
     def open(self, mode='rb'):
         self._require_file()
-        self.file.open(mode)
+        try:
+            self.file.open(mode)
+        except ValueError:
+            # if the underlaying file can't be reopened
+            # then we will use the storage to try to open it again
+            if self.file.closed:
+                # clear cached file instance
+                del self.file
+                # Because file is a property we can acces it after
+                # we deleted it
+                return self.file.open(mode)
+            raise
 
     def _get_closed(self):
         file = getattr(self, '_file', None)
@@ -92,4 +106,5 @@ class IKContentFile(ContentFile):
         return smart_str(self.file.name or '')
 
     def __unicode__(self):
-        return smart_unicode(self.file.name or u'')
+        # Python 2
+        return smart_text(self.file.name or '')

imagekit/forms/fields.py

@@ -22,8 +22,12 @@ class ProcessedImageField(ImageField, SpecHost):
     def clean(self, data, initial=None):
         data = super(ProcessedImageField, self).clean(data, initial)
 
-        if data:
+        if data and data != initial:
             spec = self.get_spec(source=data)
-            data = generate(spec)
+            f = generate(spec)
+            # Name is required in Django 1.4. When we drop support for it
+            # then we can dirrectly return the result from `generate(spec)`
+            f.name = data.name
+            return f
 
         return data

imagekit/generatorlibrary.py

@@ -4,9 +4,9 @@ from .specs import ImageSpec
 
 
 class Thumbnail(ImageSpec):
-    def __init__(self, width=None, height=None, anchor=None, crop=None, **kwargs):
+    def __init__(self, width=None, height=None, anchor=None, crop=None, upscale=None, **kwargs):
         self.processors = [ThumbnailProcessor(width, height, anchor=anchor,
-                                              crop=crop)]
+                                              crop=crop, upscale=upscale)]
         super(Thumbnail, self).__init__(**kwargs)
 
 

imagekit/hashers.py

@@ -0,0 +1,35 @@
+from copy import copy
+from hashlib import md5
+from pickle import MARK, DICT
+try:
+    from pickle import _Pickler
+except ImportError:
+    # Python 2 compatible
+    from pickle import Pickler as _Pickler
+from .lib import StringIO
+
+
+class CanonicalizingPickler(_Pickler):
+    dispatch = copy(_Pickler.dispatch)
+
+    def save_set(self, obj):
+        rv = obj.__reduce_ex__(0)
+        rv = (rv[0], (sorted(rv[1][0]),), rv[2])
+        self.save_reduce(obj=obj, *rv)
+
+    dispatch[set] = save_set
+
+    def save_dict(self, obj):
+        write = self.write
+        write(MARK + DICT)
+
+        self.memoize(obj)
+        self._batch_setitems(sorted(obj.items()))
+
+    dispatch[dict] = save_dict
+
+
+def pickle(obj):
+    file = StringIO()
+    CanonicalizingPickler(file, 0).dump(obj)
+    return md5(file.getvalue()).hexdigest()

imagekit/importers.py

@@ -1,29 +0,0 @@
-from django.utils.importlib import import_module
-import re
-import sys
-
-
-class ProcessorImporter(object):
-    """
-    The processors were moved to the PILKit project so they could be used
-    separtely from ImageKit (which has a bunch of Django dependencies). However,
-    there's no real need to expose this fact (and we want to maintain backwards
-    compatibility), so we proxy all "imagekit.processors" imports to
-    "pilkit.processors" using this object.
-
-    """
-    pattern = re.compile(r'^imagekit\.processors((\..*)?)$')
-
-    def find_module(self, name, path=None):
-        if self.pattern.match(name):
-            return self
-
-    def load_module(self, name):
-        if name in sys.modules:
-            return sys.modules[name]
-
-        new_name = self.pattern.sub(r'pilkit.processors\1', name)
-        return import_module(new_name)
-
-
-sys.meta_path.append(ProcessorImporter())

imagekit/lib.py

@@ -19,6 +19,34 @@ except ImportError:
         raise ImportError('ImageKit was unable to import the Python Imaging Library. Please confirm it`s installed and available on your current Python path.')
 
 try:
-    from cStringIO import StringIO
+    from io import BytesIO as StringIO
+except:
+    try:
+        from cStringIO import StringIO
+    except ImportError:
+        from StringIO import StringIO
+
+try:
+    from logging import NullHandler
 except ImportError:
-    from StringIO import StringIO
+    from logging import Handler
+
+    class NullHandler(Handler):
+        def emit(self, record):
+            pass
+
+# Try to import `force_text` available from Django 1.5
+# This function will replace `unicode` used in the code
+# If Django version is under 1.5 then use `force_unicde`
+# It is used for compatibility between Python 2 and Python 3
+try:
+    from django.utils.encoding import force_text, force_bytes, smart_text
+except ImportError:
+    # Django < 1.5
+    from django.utils.encoding import (force_unicode as force_text,
+                                       smart_str as force_bytes,
+                                       smart_unicode as smart_text)
+
+__all__ = ['Image', 'ImageColor', 'ImageChops', 'ImageEnhance', 'ImageFile',
+           'ImageFilter', 'ImageDraw', 'ImageStat', 'StringIO', 'NullHandler',
+           'force_text', 'force_bytes', 'smart_text']

imagekit/management/commands/generateimages.py

@@ -1,6 +1,7 @@
 from django.core.management.base import BaseCommand
 import re
 from ...registry import generator_registry, cachefile_registry
+from ...exceptions import MissingSource
 
 
 class Command(BaseCommand):
@@ -13,23 +14,28 @@ match both. Subsegments are always matched, so "a" will match "a" as
 well as "a:b" and "a:b:c".""")
     args = '[generator_ids]'
 
+    def add_arguments(self, parser):
+        parser.add_argument('generator_id', nargs='*', help='<app_name>:<model>:<field> for model specs')
+
     def handle(self, *args, **options):
         generators = generator_registry.get_ids()
 
-        if args:
-            patterns = self.compile_patterns(args)
+        generator_ids = options['generator_id'] if 'generator_id' in options else args
+        if generator_ids:
+            patterns = self.compile_patterns(generator_ids)
             generators = (id for id in generators if any(p.match(id) for p in patterns))
 
         for generator_id in generators:
             self.stdout.write('Validating generator: %s\n' % generator_id)
-            for file in cachefile_registry.get(generator_id):
-                self.stdout.write('  %s\n' % file)
-                try:
-                    # TODO: Allow other validation actions through command option
-                    file.generate()
-                except Exception, err:
-                    # TODO: How should we handle failures? Don't want to error, but should call it out more than this.
-                    self.stdout.write('    FAILED: %s\n' % err)
+            for image_file in cachefile_registry.get(generator_id):
+                if image_file.name:
+                    self.stdout.write('  %s\n' % image_file.name)
+                    try:
+                        image_file.generate()
+                    except MissingSource as err:
+                        self.stdout.write('\t No source associated with\n')
+                    except Exception as err:
+                        self.stdout.write('\tFailed %s\n' % (err))
 
     def compile_patterns(self, generator_ids):
         return [self.compile_pattern(id) for id in generator_ids]

imagekit/models/fields/__init__.py

@@ -1,4 +1,8 @@
+from __future__ import unicode_literals
+
+from django.conf import settings
 from django.db import models
+from django.db.models.signals import class_prepared
 from .files import ProcessedImageFieldFile
 from .utils import ImageSpecFileDescriptor
 from ...specs import SpecHost
@@ -7,16 +11,18 @@ from ...registry import register
 
 
 class SpecHostField(SpecHost):
-    def set_spec_id(self, cls, name):
+    def _set_spec_id(self, cls, name):
+        spec_id = getattr(self, 'spec_id', None)
+
         # Generate a spec_id to register the spec with. The default spec id is
         # "<app>:<model>_<field>"
-        if not getattr(self, 'spec_id', None):
-            spec_id = (u'%s:%s:%s' % (cls._meta.app_label,
+        if not spec_id:
+            spec_id = ('%s:%s:%s' % (cls._meta.app_label,
                             cls._meta.object_name, name)).lower()
 
-            # Register the spec with the id. This allows specs to be overridden
-            # later, from outside of the model definition.
-            super(SpecHostField, self).set_spec_id(spec_id)
+        # Register the spec with the id. This allows specs to be overridden
+        # later, from outside of the model definition.
+        super(SpecHostField, self).set_spec_id(spec_id)
 
 
 class ImageSpecField(SpecHostField):
@@ -37,16 +43,42 @@ class ImageSpecField(SpecHostField):
                 cachefile_strategy=cachefile_strategy, spec=spec,
                 spec_id=id)
 
-        # TODO: Allow callable for source. See https://github.com/jdriscoll/django-imagekit/issues/158#issuecomment-10921664
+        # TODO: Allow callable for source. See https://github.com/matthewwithanm/django-imagekit/issues/158#issuecomment-10921664
         self.source = source
 
     def contribute_to_class(self, cls, name):
-        setattr(cls, name, ImageSpecFileDescriptor(self, name))
-        self.set_spec_id(cls, name)
+        # If the source field name isn't defined, figure it out.
 
-        # Add the model and field as a source for this spec id
-        register.source_group(self.spec_id,
-                ImageFieldSourceGroup(cls, self.source))
+        def register_source_group(source):
+            setattr(cls, name, ImageSpecFileDescriptor(self, name, source))
+            self._set_spec_id(cls, name)
+
+            # Add the model and field as a source for this spec id
+            register.source_group(self.spec_id, ImageFieldSourceGroup(cls, source))
+
+        if self.source:
+            register_source_group(self.source)
+        else:
+            # The source argument is not defined
+            # Then we need to see if there is only one ImageField in that model
+            # But we need to do that after full model initialization
+            def handle_model_preparation(sender, **kwargs):
+
+                image_fields = [f.attname for f in cls._meta.fields if
+                                isinstance(f, models.ImageField)]
+                if len(image_fields) == 0:
+                    raise Exception(
+                        '%s does not define any ImageFields, so your %s'
+                        ' ImageSpecField has no image to act on.' %
+                        (cls.__name__, name))
+                elif len(image_fields) > 1:
+                    raise Exception(
+                        '%s defines multiple ImageFields, but you have not'
+                        ' specified a source for your %s ImageSpecField.' %
+                        (cls.__name__, name))
+                register_source_group(image_fields[0])
+
+            class_prepared.connect(handle_model_preparation, sender=cls, weak=False)
 
 
 class ProcessedImageField(models.ImageField, SpecHostField):
@@ -61,7 +93,7 @@ class ProcessedImageField(models.ImageField, SpecHostField):
 
     def __init__(self, processors=None, format=None, options=None,
             verbose_name=None, name=None, width_field=None, height_field=None,
-            autoconvert=True, spec=None, spec_id=None, **kwargs):
+            autoconvert=None, spec=None, spec_id=None, **kwargs):
         """
         The ProcessedImageField constructor accepts all of the arguments that
         the :class:`django.db.models.ImageField` constructor accepts, as well
@@ -69,6 +101,10 @@ class ProcessedImageField(models.ImageField, SpecHostField):
         :class:`imagekit.models.ImageSpecField`.
 
         """
+        # if spec is not provided then autoconvert will be True by default
+        if spec is None and autoconvert is None:
+            autoconvert = True
+
         SpecHost.__init__(self, processors=processors, format=format,
                 options=options, autoconvert=autoconvert, spec=spec,
                 spec_id=spec_id)
@@ -76,13 +112,15 @@ class ProcessedImageField(models.ImageField, SpecHostField):
                 height_field, **kwargs)
 
     def contribute_to_class(self, cls, name):
-        self.set_spec_id(cls, name)
+        self._set_spec_id(cls, name)
         return super(ProcessedImageField, self).contribute_to_class(cls, name)
 
 
-try:
-    from south.modelsinspector import add_introspection_rules
-except ImportError:
-    pass
-else:
-    add_introspection_rules([], [r'^imagekit\.models\.fields\.ProcessedImageField$'])
+# If the project does not use south, then we will not try to add introspection
+if 'south' in settings.INSTALLED_APPS:
+    try:
+        from south.modelsinspector import add_introspection_rules
+    except ImportError:
+        pass
+    else:
+        add_introspection_rules([], [r'^imagekit\.models\.fields\.ProcessedImageField$'])

imagekit/models/fields/utils.py

@@ -1,34 +1,17 @@
 from ...cachefiles import ImageCacheFile
-from django.db.models.fields.files import ImageField
 
 
 class ImageSpecFileDescriptor(object):
-    def __init__(self, field, attname):
+    def __init__(self, field, attname, source_field_name):
         self.attname = attname
         self.field = field
+        self.source_field_name = source_field_name
 
     def __get__(self, instance, owner):
         if instance is None:
             return self.field
         else:
-            field_name = getattr(self.field, 'source', None)
-            if field_name:
-                source = getattr(instance, field_name)
-            else:
-                image_fields = [getattr(instance, f.attname) for f in
-                        instance.__class__._meta.fields if
-                        isinstance(f, ImageField)]
-                if len(image_fields) == 0:
-                    raise Exception('%s does not define any ImageFields, so your'
-                            ' %s ImageSpecField has no image to act on.' %
-                            (instance.__class__.__name__, self.attname))
-                elif len(image_fields) > 1:
-                    raise Exception('%s defines multiple ImageFields, but you'
-                            ' have not specified a source for your %s'
-                            ' ImageSpecField.' % (instance.__class__.__name__,
-                            self.attname))
-                else:
-                    source = image_fields[0]
+            source = getattr(instance, self.source_field_name)
             spec = self.field.get_spec(source=source)
             file = ImageCacheFile(spec)
             instance.__dict__[self.attname] = file

imagekit/pkgmeta.py

@@ -1,5 +1,5 @@
 __title__ = 'django-imagekit'
-__author__ = 'Justin Driscoll, Bryan Veloso, Greg Newman, Chris Drackett, Matthew Tretter, Eric Eldredge'
-__version__ = '3.0a3'
+__author__ = 'Matthew Tretter, Venelin Stoykov, Eric Eldredge, Bryan Veloso, Greg Newman, Chris Drackett, Justin Driscoll'
+__version__ = '4.0.2'
 __license__ = 'BSD'
 __all__ = ['__title__', '__author__', '__version__', '__license__']

imagekit/processors/__init__.py

@@ -0,0 +1,12 @@
+from pilkit.processors import *
+
+__all__ = [
+	# Base
+	'ProcessorPipeline', 'Adjust', 'Reflection', 'Transpose',
+	'Anchor', 'MakeOpaque',
+	# Crop
+	'TrimBorderColor', 'Crop', 'SmartCrop',
+	# Resize
+	'Resize', 'ResizeToCover', 'ResizeToFill', 'SmartResize',
+	'ResizeCanvas', 'AddBorder', 'ResizeToFit', 'Thumbnail'
+]

imagekit/processors/base.py

@@ -0,0 +1,7 @@
+import warnings
+
+from pilkit.processors.base import *
+
+warnings.warn('imagekit.processors.base is deprecated use imagekit.processors instead', DeprecationWarning)
+
+__all__ = ['ProcessorPipeline', 'Adjust', 'Reflection', 'Transpose', 'Anchor', 'MakeOpaque']

imagekit/processors/crop.py

@@ -0,0 +1,7 @@
+import warnings
+
+from pilkit.processors.crop import *
+
+warnings.warn('imagekit.processors.crop is deprecated use imagekit.processors instead', DeprecationWarning)
+
+__all__ = ['TrimBorderColor', 'Crop', 'SmartCrop']

imagekit/processors/resize.py

@@ -0,0 +1,7 @@
+import warnings
+
+from pilkit.processors.resize import *
+
+warnings.warn('imagekit.processors.resize is deprecated use imagekit.processors instead', DeprecationWarning)
+
+__all__ = ['Resize', 'ResizeToCover', 'ResizeToFill', 'SmartResize', 'ResizeCanvas', 'AddBorder', 'ResizeToFit', 'Thumbnail']

imagekit/processors/utils.py

@@ -0,0 +1,5 @@
+import warnings
+
+from pilkit.processors.utils import *
+
+warnings.warn('imagekit.processors.utils is deprecated use pilkit.processors.utils instead', DeprecationWarning)

imagekit/registry.py

@@ -1,6 +1,6 @@
 from .exceptions import AlreadyRegistered, NotRegistered
-from .signals import before_access, source_created, source_changed, source_deleted
-from .utils import call_strategy_method
+from .signals import content_required, existence_required, source_saved
+from .utils import autodiscover, call_strategy_method
 
 
 class GeneratorRegistry(object):
@@ -12,16 +12,17 @@ class GeneratorRegistry(object):
     """
     def __init__(self):
         self._generators = {}
-        before_access.connect(self.before_access_receiver)
+        content_required.connect(self.content_required_receiver)
+        existence_required.connect(self.existence_required_receiver)
 
     def register(self, id, generator):
-        if id in self._generators:
+        registered_generator = self._generators.get(id)
+        if registered_generator and generator != self._generators[id]:
             raise AlreadyRegistered('The generator with id %s is'
                                     ' already registered' % id)
         self._generators[id] = generator
 
-    def unregister(self, id, generator):
-        # TODO: Either don't require the generator, or--if we do--assert that it's registered with the provided id
+    def unregister(self, id):
         try:
             del self._generators[id]
         except KeyError:
@@ -29,6 +30,8 @@ class GeneratorRegistry(object):
                                 ' registered' % id)
 
     def get(self, id, **kwargs):
+        autodiscover()
+
         try:
             generator = self._generators[id]
         except KeyError:
@@ -40,15 +43,22 @@ class GeneratorRegistry(object):
             return generator
 
     def get_ids(self):
+        autodiscover()
         return self._generators.keys()
 
-    def before_access_receiver(self, sender, file, **kwargs):
+    def content_required_receiver(self, sender, file, **kwargs):
+        self._receive(file, 'on_content_required')
+
+    def existence_required_receiver(self, sender, file, **kwargs):
+        self._receive(file, 'on_existence_required')
+
+    def _receive(self, file, callback):
         generator = file.generator
 
         # FIXME: I guess this means you can't register functions?
         if generator.__class__ in self._generators.values():
             # Only invoke the strategy method for registered generators.
-            call_strategy_method(generator, 'before_access', file=file)
+            call_strategy_method(file, callback)
 
 
 class SourceGroupRegistry(object):
@@ -62,9 +72,7 @@ class SourceGroupRegistry(object):
 
     """
     _signals = {
-        source_created: 'on_source_created',
-        source_changed: 'on_source_changed',
-        source_deleted: 'on_source_deleted',
+        source_saved: 'on_source_saved',
     }
 
     def __init__(self):
@@ -105,7 +113,7 @@ class SourceGroupRegistry(object):
 
         for spec in specs:
             file = ImageCacheFile(spec)
-            call_strategy_method(spec, callback_name, file=file)
+            call_strategy_method(file, callback_name)
 
 
 class CacheFileRegistry(object):
@@ -176,8 +184,8 @@ class Unregister(object):
     Unregister generators and generated files.
 
     """
-    def generator(self, id, generator):
-        generator_registry.unregister(id, generator)
+    def generator(self, id):
+        generator_registry.unregister(id)
 
     def cachefiles(self, generator_id, cachefiles):
         cachefile_registry.unregister(generator_id, cachefiles)

imagekit/signals.py

@@ -2,9 +2,8 @@ from django.dispatch import Signal
 
 
 # Generated file signals
-before_access = Signal()
+content_required = Signal()
+existence_required = Signal()
 
 # Source group signals
-source_created = Signal()
-source_changed = Signal()
-source_deleted = Signal()
+source_saved = Signal()

imagekit/specs/__init__.py

@@ -1,11 +1,11 @@
+from copy import copy
 from django.conf import settings
 from django.db.models.fields.files import ImageFieldFile
-from hashlib import md5
-import pickle
 from ..cachefiles.backends import get_default_cachefile_backend
-from ..cachefiles.strategies import StrategyWrapper
-from ..processors import ProcessorPipeline
-from ..utils import open_image, img_to_fobj, get_by_qname
+from ..cachefiles.strategies import load_strategy
+from .. import hashers
+from ..exceptions import AlreadyRegistered, MissingSource
+from ..utils import open_image, get_by_qname, process_image
 from ..registry import generator_registry, register
 
 
@@ -36,11 +36,18 @@ class BaseImageSpec(object):
 
     def __init__(self):
         self.cachefile_backend = self.cachefile_backend or get_default_cachefile_backend()
-        self.cachefile_strategy = StrategyWrapper(self.cachefile_strategy)
+        self.cachefile_strategy = load_strategy(self.cachefile_strategy)
 
     def generate(self):
         raise NotImplementedError
 
+    MissingSource = MissingSource
+    """
+    Raised when an operation requiring a source is attempted on a spec that has
+    no source.
+
+    """
+
 
 class ImageSpec(BaseImageSpec):
     """
@@ -82,51 +89,81 @@ class ImageSpec(BaseImageSpec):
 
     @property
     def cachefile_name(self):
+        if not self.source:
+            return None
         fn = get_by_qname(settings.IMAGEKIT_SPEC_CACHEFILE_NAMER, 'namer')
         return fn(self)
 
+    @property
+    def source(self):
+        src = getattr(self, '_source', None)
+        if not src:
+            field_data = getattr(self, '_field_data', None)
+            if field_data:
+                src = self._source = getattr(field_data['instance'], field_data['attname'])
+                del self._field_data
+        return src
+
+    @source.setter
+    def source(self, value):
+        self._source = value
+
     def __getstate__(self):
-        state = self.__dict__
+        state = copy(self.__dict__)
 
         # Unpickled ImageFieldFiles won't work (they're missing a storage
         # object). Since they're such a common use case, we special case them.
+        # Unfortunately, this also requires us to add the source getter to
+        # lazily retrieve the source on the reconstructed object; simply trying
+        # to look up the source in ``__setstate__`` would require us to get the
+        # model instance but, if ``__setstate__`` was called as part of
+        # deserializing that model, the model wouldn't be fully reconstructed
+        # yet, preventing us from accessing the source field.
+        # (This is issue #234.)
         if isinstance(self.source, ImageFieldFile):
             field = getattr(self.source, 'field')
             state['_field_data'] = {
                 'instance': getattr(self.source, 'instance', None),
                 'attname': getattr(field, 'name', None),
             }
+            state.pop('_source', None)
         return state
 
-    def __setstate__(self, state):
-        field_data = state.pop('_field_data', None)
-        self.__dict__ = state
-        if field_data:
-            self.source = getattr(field_data['instance'], field_data['attname'])
-
     def get_hash(self):
-        return md5(pickle.dumps([
+        return hashers.pickle([
             self.source.name,
             self.processors,
             self.format,
             self.options,
             self.autoconvert,
-        ])).hexdigest()
+        ])
 
     def generate(self):
+        if not self.source:
+            raise MissingSource("The spec '%s' has no source file associated"
+                                " with it." % self)
+
         # TODO: Move into a generator base class
         # TODO: Factor out a generate_image function so you can create a generator and only override the PIL.Image creating part. (The tricky part is how to deal with original_format since generator base class won't have one.)
-        img = open_image(self.source)
-        original_format = img.format
 
-        # Run the processors
-        processors = self.processors
-        img = ProcessorPipeline(processors or []).process(img)
+        closed = self.source.closed
+        if closed:
+            # Django file object should know how to reopen itself if it was closed
+            # https://code.djangoproject.com/ticket/13750
+            self.source.open()
 
-        options = dict(self.options or {})
-        format = self.format or img.format or original_format or 'JPEG'
-        content = img_to_fobj(img, format, **options)
-        return content
+        try:
+            img = open_image(self.source)
+            new_image = process_image(img,
+                                      processors=self.processors,
+                                      format=self.format,
+                                      autoconvert=self.autoconvert,
+                                      options=self.options)
+        finally:
+            if closed:
+                # We need to close the file if it was opened by us
+                self.source.close()
+        return new_image
 
 
 def create_spec_class(class_attrs):
@@ -188,7 +225,17 @@ class SpecHost(object):
 
         """
         self.spec_id = id
-        register.generator(id, self._original_spec)
+
+        if self._original_spec:
+            try:
+                register.generator(id, self._original_spec)
+            except AlreadyRegistered:
+                # Fields should not cause AlreadyRegistered exceptions. If a
+                # spec is already registered, that should be used. It is
+                # especially important that an error is not thrown here because
+                # of South, which will create duplicate models as part of its
+                # "fake orm," therefore re-registering specs.
+                pass
 
     def get_spec(self, source):
         """

imagekit/specs/sourcegroups.py

@@ -2,20 +2,19 @@
 Source groups are the means by which image spec sources are identified. They
 have two responsibilities:
 
-1. To dispatch ``source_created``, ``source_changed``, and ``source_deleted``
-   signals. (These will be relayed to the corresponding specs' cache file
-   strategies.)
+1. To dispatch ``source_saved`` signals. (These will be relayed to the
+   corresponding specs' cache file strategies.)
 2. To provide the source files that they represent, via a generator method named
    ``files()``. (This is used by the generateimages management command for
    "pre-caching" image files.)
 
 """
 
-from django.db.models.signals import post_init, post_save, post_delete
+from django.db.models.signals import post_init, post_save
 from django.utils.functional import wraps
 import inspect
 from ..cachefiles import LazyImageCacheFile
-from ..signals import source_created, source_changed, source_deleted
+from ..signals import source_saved
 from ..utils import get_nonabstract_descendants
 
 
@@ -48,7 +47,7 @@ class ModelSignalRouter(object):
     ``ImageFieldSourceGroup``s. This class encapsulates that functionality.
 
     Related:
-        https://github.com/jdriscoll/django-imagekit/issues/126
+        https://github.com/matthewwithanm/django-imagekit/issues/126
         https://code.djangoproject.com/ticket/9318
 
     """
@@ -58,7 +57,6 @@ class ModelSignalRouter(object):
         uid = 'ik_spec_field_receivers'
         post_init.connect(self.post_init_receiver, dispatch_uid=uid)
         post_save.connect(self.post_save_receiver, dispatch_uid=uid)
-        post_delete.connect(self.post_delete_receiver, dispatch_uid=uid)
 
     def add(self, source_group):
         self._source_groups.append(source_group)
@@ -74,41 +72,45 @@ class ModelSignalRouter(object):
 
         """
         self.init_instance(instance)
-        instance._ik['source_hashes'] = dict((attname, hash(file_field))
-                for attname, file_field in self.get_field_dict(instance).items())
+        instance._ik['source_hashes'] = dict(
+            (attname, hash(getattr(instance, attname)))
+            for attname in self.get_source_fields(instance))
         return instance._ik['source_hashes']
 
-    def get_field_dict(self, instance):
+    def get_source_fields(self, instance):
         """
-        Returns the source fields for the given instance, in a dictionary whose
-        keys are the field names and values are the fields themselves.
+        Returns a list of the source fields for the given instance.
 
         """
-        return dict((src.image_field, getattr(instance, src.image_field)) for
-                src in self._source_groups if isinstance(instance, src.model_class))
+        return set(src.image_field
+                   for src in self._source_groups
+                   if isinstance(instance, src.model_class))
 
     @ik_model_receiver
-    def post_save_receiver(self, sender, instance=None, created=False, raw=False, **kwargs):
+    def post_save_receiver(self, sender, instance=None, created=False, update_fields=None, raw=False, **kwargs):
         if not raw:
             self.init_instance(instance)
             old_hashes = instance._ik.get('source_hashes', {}).copy()
             new_hashes = self.update_source_hashes(instance)
-            for attname, file in self.get_field_dict(instance).items():
-                if created:
-                    self.dispatch_signal(source_created, file, sender, instance,
-                                         attname)
-                elif old_hashes[attname] != new_hashes[attname]:
-                    self.dispatch_signal(source_changed, file, sender, instance,
-                                         attname)
+            for attname in self.get_source_fields(instance):
+                if update_fields and attname not in update_fields:
+                    continue
 
-    @ik_model_receiver
-    def post_delete_receiver(self, sender, instance=None, **kwargs):
-        for attname, file in self.get_field_dict(instance).items():
-            self.dispatch_signal(source_deleted, file, sender, instance, attname)
+                file = getattr(instance, attname)
+                if file and old_hashes.get(attname) != new_hashes[attname]:
+                    self.dispatch_signal(source_saved, file, sender, instance,
+                                         attname)
 
     @ik_model_receiver
     def post_init_receiver(self, sender, instance=None, **kwargs):
-        self.update_source_hashes(instance)
+        self.init_instance(instance)
+        source_fields = self.get_source_fields(instance)
+        local_fields = dict((field.name, field)
+                            for field in instance._meta.local_fields
+                            if field.name in source_fields)
+        instance._ik['source_hashes'] = dict(
+            (attname, hash(file_field))
+            for attname, file_field in local_fields.items())
 
     def dispatch_signal(self, signal, file, model_class, instance, attname):
         """

imagekit/templatetags/imagekit.py

@@ -1,9 +1,13 @@
+from __future__ import unicode_literals
+
 from django import template
 from django.utils.html import escape
 from django.utils.safestring import mark_safe
-from .compat import parse_bits
+
+from ..compat import parse_bits
 from ..cachefiles import ImageCacheFile
 from ..registry import generator_registry
+from ..lib import force_text
 
 
 register = template.Library()
@@ -28,7 +32,7 @@ def parse_dimensions(dimensions):
     will be None for that value.
 
     """
-    width, height = [d.strip() or None for d in dimensions.split('x')]
+    width, height = [d.strip() and int(d) or None for d in dimensions.split('x')]
     return dict(width=width, height=height)
 
 
@@ -40,12 +44,9 @@ class GenerateImageAssignmentNode(template.Node):
         self._variable_name = variable_name
 
     def get_variable_name(self, context):
-        return unicode(self._variable_name)
+        return force_text(self._variable_name)
 
     def render(self, context):
-        from ..utils import autodiscover
-        autodiscover()
-
         variable_name = self.get_variable_name(context)
         context[variable_name] = get_cachefile(context, self._generator_id,
                 self._generator_kwargs)
@@ -60,9 +61,6 @@ class GenerateImageTagNode(template.Node):
         self._html_attrs = html_attrs
 
     def render(self, context):
-        from ..utils import autodiscover
-        autodiscover()
-
         file = get_cachefile(context, self._generator_id,
                 self._generator_kwargs)
         attrs = dict((k, v.resolve(context)) for k, v in
@@ -76,7 +74,7 @@ class GenerateImageTagNode(template.Node):
         attrs['src'] = file.url
         attr_str = ' '.join('%s="%s"' % (escape(k), escape(v)) for k, v in
                 attrs.items())
-        return mark_safe(u'<img %s />' % attr_str)
+        return mark_safe('<img %s />' % attr_str)
 
 
 class ThumbnailAssignmentNode(template.Node):
@@ -89,12 +87,9 @@ class ThumbnailAssignmentNode(template.Node):
         self._generator_kwargs = generator_kwargs
 
     def get_variable_name(self, context):
-        return unicode(self._variable_name)
+        return force_text(self._variable_name)
 
     def render(self, context):
-        from ..utils import autodiscover
-        autodiscover()
-
         variable_name = self.get_variable_name(context)
 
         generator_id = self._generator_id.resolve(context) if self._generator_id else DEFAULT_THUMBNAIL_GENERATOR
@@ -119,9 +114,6 @@ class ThumbnailImageTagNode(template.Node):
         self._html_attrs = html_attrs
 
     def render(self, context):
-        from ..utils import autodiscover
-        autodiscover()
-
         generator_id = self._generator_id.resolve(context) if self._generator_id else DEFAULT_THUMBNAIL_GENERATOR
         dimensions = parse_dimensions(self._dimensions.resolve(context))
         kwargs = dict((k, v.resolve(context)) for k, v in
@@ -143,7 +135,7 @@ class ThumbnailImageTagNode(template.Node):
         attrs['src'] = file.url
         attr_str = ' '.join('%s="%s"' % (escape(k), escape(v)) for k, v in
                 attrs.items())
-        return mark_safe(u'<img %s />' % attr_str)
+        return mark_safe('<img %s />' % attr_str)
 
 
 def parse_ik_tag_bits(parser, bits):

imagekit/utils.py

@@ -1,27 +1,23 @@
+from __future__ import unicode_literals
 import logging
+import re
 from tempfile import NamedTemporaryFile
+from hashlib import md5
 
+from django.conf import settings
 from django.core.exceptions import ImproperlyConfigured
 from django.core.files import File
-from django.db.models.loading import cache
-from django.utils.importlib import import_module
+try:
+    from importlib import import_module
+except ImportError:
+    from django.utils.importlib import import_module
 from pilkit.utils import *
+from .lib import NullHandler, force_bytes
 
 
-def get_spec_files(instance):
-    try:
-        return instance._ik.spec_files
-    except AttributeError:
-        return []
-
-
-def _get_models(apps):
-    models = []
-    for app_label in apps or []:
-        app = cache.get_app(app_label)
-        models += [m for m in cache.get_models(app)]
-    return models
+bad_memcached_key_chars = re.compile('[\u0000-\u001f\\s]+')
 
+_autodiscovered = False
 
 def get_nonabstract_descendants(model):
     """ Returns all non-abstract descendants of the model. """
@@ -40,7 +36,7 @@ def get_by_qname(path, desc):
     module, objname = path[:dot], path[dot + 1:]
     try:
         mod = import_module(module)
-    except ImportError, e:
+    except ImportError as e:
         raise ImproperlyConfigured('Error importing %s module %s: "%s"' %
                 (desc, module, e))
     try:
@@ -71,28 +67,60 @@ def autodiscover():
 
     Copied from django.contrib.admin
     """
+    global _autodiscovered
 
+    if _autodiscovered:
+        return
+
+    try:
+        from django.utils.module_loading import autodiscover_modules
+    except ImportError:
+        # Django<1.7
+        _autodiscover_modules_fallback()
+    else:
+        autodiscover_modules('imagegenerators')
+    _autodiscovered = True
+
+
+def _autodiscover_modules_fallback():
+    """
+    Auto-discover INSTALLED_APPS imagegenerators.py modules and fail silently
+    when not present. This forces an import on them to register any admin bits
+    they may want.
+
+    Copied from django.contrib.admin
+
+    Used for Django versions < 1.7
+    """
     from django.conf import settings
-    from django.utils.importlib import import_module
+    try:
+        from importlib import import_module
+    except ImportError:
+        from django.utils.importlib import import_module
     from django.utils.module_loading import module_has_submodule
 
     for app in settings.INSTALLED_APPS:
-        mod = import_module(app)
-        # Attempt to import the app's admin module.
+        # As of Django 1.7, settings.INSTALLED_APPS may contain classes instead of modules, hence the try/except
+        # See here: https://docs.djangoproject.com/en/dev/releases/1.7/#introspecting-applications
         try:
-            import_module('%s.imagegenerators' % app)
-        except:
-            # Decide whether to bubble up this error. If the app just
-            # doesn't have an imagegenerators module, we can ignore the error
-            # attempting to import it, otherwise we want it to bubble up.
-            if module_has_submodule(mod, 'imagegenerators'):
-                raise
+            mod = import_module(app)
+            # Attempt to import the app's admin module.
+            try:
+                import_module('%s.imagegenerators' % app)
+            except:
+                # Decide whether to bubble up this error. If the app just
+                # doesn't have an imagegenerators module, we can ignore the error
+                # attempting to import it, otherwise we want it to bubble up.
+                if module_has_submodule(mod, 'imagegenerators'):
+                    raise
+        except ImportError:
+            pass
 
 
 def get_logger(logger_name='imagekit', add_null_handler=True):
     logger = logging.getLogger(logger_name)
     if add_null_handler:
-        logger.addHandler(logging.NullHandler())
+        logger.addHandler(NullHandler())
     return logger
 
 
@@ -122,20 +150,42 @@ def generate(generator):
 
     """
     content = generator.generate()
-
-    # If the file doesn't have a name, Django will raise an Exception while
-    # trying to save it, so we create a named temporary file.
-    if not getattr(content, 'name', None):
-        f = NamedTemporaryFile()
-        f.write(content.read())
-        f.seek(0)
-        content = f
-
-    return File(content)
+    f = File(content)
+    # The size of the File must be known or Django will try to open a file
+    # without a name and raise an Exception.
+    f.size = len(content.read())
+    # After getting the size reset the file pointer for future reads.
+    content.seek(0)
+    return f
 
 
-def call_strategy_method(generator, method_name, *args, **kwargs):
-    strategy = getattr(generator, 'cachefile_strategy', None)
+def call_strategy_method(file, method_name):
+    strategy = getattr(file, 'cachefile_strategy', None)
     fn = getattr(strategy, method_name, None)
     if fn is not None:
-        fn(*args, **kwargs)
+        fn(file)
+
+
+def get_cache():
+    try:
+        from django.core.cache import caches
+    except ImportError:
+        # Django < 1.7
+        from django.core.cache import get_cache
+        return get_cache(settings.IMAGEKIT_CACHE_BACKEND)
+
+    return caches[settings.IMAGEKIT_CACHE_BACKEND]
+
+
+def sanitize_cache_key(key):
+    if settings.IMAGEKIT_USE_MEMCACHED_SAFE_CACHE_KEY:
+        # Memcached keys can't contain whitespace or control characters.
+        new_key = bad_memcached_key_chars.sub('', key)
+
+        # The also can't be > 250 chars long. Since we don't know what the
+        # user's cache ``KEY_FUNCTION`` setting is like, we'll limit it to 200.
+        if len(new_key) >= 200:
+            new_key = '%s:%s' % (new_key[:200-33], md5(force_bytes(key)).hexdigest())
+
+        key = new_key
+    return key

setup.cfg

@@ -0,0 +1,2 @@
+[bdist_wheel]
+universal = 1

setup.py

@@ -1,4 +1,4 @@
-#/usr/bin/env python
+#!/usr/bin/env python
 import codecs
 import os
 from setuptools import setup, find_packages
@@ -7,23 +7,27 @@ import sys
 
 # Workaround for multiprocessing/nose issue. See http://bugs.python.org/msg170215
 try:
-    import multiprocessing
+    import multiprocessing  # NOQA
 except ImportError:
     pass
 
 
 if 'publish' in sys.argv:
-    os.system('python setup.py sdist upload')
+    os.system('python setup.py sdist bdist_wheel upload')
     sys.exit()
 
 
 read = lambda filepath: codecs.open(filepath, 'r', 'utf-8').read()
 
 
+def exec_file(filepath, globalz=None, localz=None):
+        exec(read(filepath), globalz, localz)
+
+
 # Load package meta from the pkgmeta module without loading imagekit.
 pkgmeta = {}
-execfile(os.path.join(os.path.dirname(__file__),
-         'imagekit', 'pkgmeta.py'), pkgmeta)
+exec_file(os.path.join(os.path.dirname(__file__),
+          'imagekit', 'pkgmeta.py'), pkgmeta)
 
 
 setup(
@@ -31,27 +35,33 @@ setup(
     version=pkgmeta['__version__'],
     description='Automated image processing for Django models.',
     long_description=read(os.path.join(os.path.dirname(__file__), 'README.rst')),
-    author='Justin Driscoll',
-    author_email='justin@driscolldev.com',
+    author='Matthew Tretter',
+    author_email='m@tthewwithanm.com',
     maintainer='Bryan Veloso',
     maintainer_email='bryan@revyver.com',
     license='BSD',
-    url='http://github.com/jdriscoll/django-imagekit/',
-    packages=find_packages(),
+    url='http://github.com/matthewwithanm/django-imagekit/',
+    packages=find_packages(exclude=['*.tests', '*.tests.*', 'tests.*', 'tests']),
     zip_safe=False,
     include_package_data=True,
     tests_require=[
-        'beautifulsoup4==4.1.3',
-        'nose==1.2.1',
-        'nose-progressive==1.3',
-        'django-nose==1.1',
-        'Pillow==1.7.8',
+        'beautifulsoup4>=4.4.0',
+        'nose>=1.3.6',
+        'nose-progressive>=1.5.1',
+        'django-nose>=1.4',
+        'Pillow',
+        'mock>=1.0.1',
     ],
     test_suite='testrunner.run_tests',
     install_requires=[
         'django-appconf>=0.5',
-        'pilkit',
+        'pilkit>=0.2.0',
+        'six',
     ],
+    extras_require={
+        'async': ['django-celery>=3.0'],
+        'async_rq': ['django-rq>=0.6.0'],
+    },
     classifiers=[
         'Development Status :: 5 - Production/Stable',
         'Environment :: Web Environment',
@@ -59,9 +69,12 @@ setup(
         'Intended Audience :: Developers',
         'License :: OSI Approved :: BSD License',
         'Operating System :: OS Independent',
-        'Programming Language :: Python :: 2.5',
-        'Programming Language :: Python :: 2.6',
+        'Programming Language :: Python :: 2',
         'Programming Language :: Python :: 2.7',
+        'Programming Language :: Python :: 3',
+        'Programming Language :: Python :: 3.3',
+        'Programming Language :: Python :: 3.4',
+        'Programming Language :: Python :: 3.5',
         'Topic :: Utilities'
     ],
 )

testrunner.py

@@ -16,4 +16,7 @@ def run_tests():
     cls = get_runner(settings)
     runner = cls()
     failures = runner.run_tests(['tests'])
+    # Clean autogenerated junk before exit
+    from tests.utils import clear_imagekit_test_files
+    clear_imagekit_test_files()
     sys.exit(failures)

tests/models.py

@@ -1,10 +1,17 @@
 from django.db import models
 
+from imagekit import ImageSpec
 from imagekit.models import ProcessedImageField
 from imagekit.models import ImageSpecField
 from imagekit.processors import Adjust, ResizeToFill, SmartCrop
 
 
+class Thumbnail(ImageSpec):
+    processors = [ResizeToFill(100, 60)]
+    format = 'JPEG'
+    options = {'quality': 60}
+
+
 class ImageModel(models.Model):
     image = models.ImageField(upload_to='b')
 
@@ -12,9 +19,10 @@ class ImageModel(models.Model):
 class Photo(models.Model):
     original_image = models.ImageField(upload_to='photos')
 
+    # Implicit source field
     thumbnail = ImageSpecField([Adjust(contrast=1.2, sharpness=1.1),
-            ResizeToFill(50, 50)], source='original_image', format='JPEG',
-            options={'quality': 90})
+                               ResizeToFill(50, 50)], format='JPEG',
+                               options={'quality': 90})
 
     smartcropped_thumbnail = ImageSpecField([Adjust(contrast=1.2,
             sharpness=1.1), SmartCrop(50, 50)], source='original_image',
@@ -26,20 +34,24 @@ class ProcessedImageFieldModel(models.Model):
             options={'quality': 90}, upload_to='p')
 
 
+class ProcessedImageFieldWithSpecModel(models.Model):
+    processed = ProcessedImageField(spec=Thumbnail, upload_to='p')
+
+
 class CountingCacheFileStrategy(object):
     def __init__(self):
-        self.before_access_count = 0
-        self.on_source_changed_count = 0
-        self.on_source_created_count = 0
+        self.on_existence_required_count = 0
+        self.on_content_required_count = 0
+        self.on_source_saved_count = 0
 
-    def before_access(self, file):
-        self.before_access_count += 1
+    def on_existence_required(self, file):
+        self.on_existence_required_count += 1
 
-    def on_source_changed(self, file):
-        self.on_source_changed_count += 1
+    def on_content_required(self, file):
+        self.on_content_required_count += 1
 
-    def on_source_created(self, file):
-        self.on_source_created_count += 1
+    def on_source_saved(self, file):
+        self.on_source_saved_count += 1
 
 
 class AbstractImageModel(models.Model):

tests/settings.py

@@ -21,6 +21,8 @@ DATABASES = {
     },
 }
 
+SECRET_KEY = '_uobce43e5osp8xgzle*yag2_16%y$sf*5(12vfg25hpnxik_*'
+
 INSTALLED_APPS = [
     'django.contrib.auth',
     'django.contrib.contenttypes',
@@ -32,7 +34,6 @@ INSTALLED_APPS = [
 TEST_RUNNER = 'django_nose.NoseTestSuiteRunner'
 NOSE_ARGS = [
     '-s',
-    '--with-progressive',
 
     # When the tests are run --with-coverage, these args configure coverage
     # reporting (requires coverage to be installed).
@@ -43,6 +44,26 @@ NOSE_ARGS = [
     '--cover-html-dir=%s' % os.path.join(BASE_PATH, 'cover')
 ]
 
-DEBUG = True
-TEMPLATE_DEBUG = DEBUG
+if os.getenv('TERM'):
+    NOSE_ARGS.append('--with-progressive')
+
 CACHE_BACKEND = 'locmem://'
+
+# Django >= 1.8
+TEMPLATES = [
+    {
+        'BACKEND': 'django.template.backends.django.DjangoTemplates',
+        'APP_DIRS': True,
+        'OPTIONS': {
+            'context_processors': [
+                'django.contrib.auth.context_processors.auth',
+                'django.template.context_processors.debug',
+                'django.template.context_processors.i18n',
+                'django.template.context_processors.media',
+                'django.template.context_processors.static',
+                'django.template.context_processors.tz',
+                'django.contrib.messages.context_processors.messages',
+            ],
+        },
+    },
+]

tests/test_abstract_models.py

@@ -1,27 +1,7 @@
-from django.core.files import File
-from imagekit.signals import source_created
-from imagekit.specs.sourcegroups import ImageFieldSourceGroup
 from imagekit.utils import get_nonabstract_descendants
 from nose.tools import eq_
 from . models import (AbstractImageModel, ConcreteImageModel,
-    ConcreteImageModelSubclass)
-from .utils import get_image_file
-
-
-def test_source_created_signal():
-    source_group = ImageFieldSourceGroup(AbstractImageModel, 'original_image')
-    count = [0]
-
-    def receiver(sender, *args, **kwargs):
-        if sender is source_group:
-            count[0] += 1
-
-    source_created.connect(receiver, dispatch_uid='test_source_created')
-    instance = ConcreteImageModel()
-    img = File(get_image_file())
-    instance.original_image.save('test_source_created_signal.jpg', img)
-
-    eq_(count[0], 1)
+                      ConcreteImageModelSubclass)
 
 
 def test_nonabstract_descendants_generator():

tests/test_cachefiles.py

@@ -0,0 +1,115 @@
+from unittest import mock
+from django.conf import settings
+from hashlib import md5
+from imagekit.cachefiles import ImageCacheFile, LazyImageCacheFile
+from imagekit.cachefiles.backends import Simple
+from imagekit.lib import force_bytes
+from nose.tools import raises, eq_
+from .imagegenerators import TestSpec
+from .utils import (assert_file_is_truthy, assert_file_is_falsy,
+                    DummyAsyncCacheFileBackend, get_unique_image_file,
+                    get_image_file)
+
+
+def test_no_source_falsiness():
+    """
+    Ensure cache files generated from sourceless specs are falsy.
+
+    """
+    spec = TestSpec(source=None)
+    file = ImageCacheFile(spec)
+    assert_file_is_falsy(file)
+
+
+def test_sync_backend_truthiness():
+    """
+    Ensure that a cachefile with a synchronous cache file backend (the default)
+    is truthy.
+
+    """
+    spec = TestSpec(source=get_unique_image_file())
+    file = ImageCacheFile(spec)
+    assert_file_is_truthy(file)
+
+
+def test_async_backend_falsiness():
+    """
+    Ensure that a cachefile with an asynchronous cache file backend is falsy.
+
+    """
+    spec = TestSpec(source=get_unique_image_file())
+    file = ImageCacheFile(spec, cachefile_backend=DummyAsyncCacheFileBackend())
+    assert_file_is_falsy(file)
+
+
+@raises(TestSpec.MissingSource)
+def test_no_source_error():
+    spec = TestSpec(source=None)
+    file = ImageCacheFile(spec)
+    file.generate()
+
+
+def test_repr_does_not_send_existence_required():
+    """
+    Ensure that `__repr__` method does not send `existance_required` signal
+
+    Cachefile strategy may be configured to generate file on
+    `existance_required`.
+    To generate images, backend passes `ImageCacheFile` instance to worker.
+    Both celery and RQ calls `__repr__` method for each argument to enque call.
+    And if `__repr__` of object will send this signal, we will get endless
+    recursion
+
+    """
+    with mock.patch('imagekit.cachefiles.existence_required') as signal:
+        # import here to apply mock
+        from imagekit.cachefiles import ImageCacheFile
+
+        spec = TestSpec(source=get_unique_image_file())
+        file = ImageCacheFile(
+            spec,
+            cachefile_backend=DummyAsyncCacheFileBackend()
+        )
+        file.__repr__()
+        eq_(signal.send.called, False)
+
+
+def test_memcached_cache_key():
+    """
+    Ensure the default cachefile backend is sanitizing its cache key for
+    memcached by default.
+
+    """
+
+    class MockFile(object):
+        def __init__(self, name):
+            self.name = name
+
+    backend = Simple()
+    extra_char_count = len('state-') + len(settings.IMAGEKIT_CACHE_PREFIX)
+
+    length = 199 - extra_char_count
+    filename = '1' * length
+    file = MockFile(filename)
+    eq_(backend.get_key(file), '%s%s-state' %
+        (settings.IMAGEKIT_CACHE_PREFIX, file.name))
+
+    length = 200 - extra_char_count
+    filename = '1' * length
+    file = MockFile(filename)
+    eq_(backend.get_key(file), '%s%s:%s' % (
+        settings.IMAGEKIT_CACHE_PREFIX,
+        '1' * (200 - len(':') - 32 - len(settings.IMAGEKIT_CACHE_PREFIX)),
+        md5(force_bytes('%s%s-state' % (settings.IMAGEKIT_CACHE_PREFIX, filename))).hexdigest()))
+
+
+def test_lazyfile_stringification():
+    file = LazyImageCacheFile('testspec', source=None)
+    eq_(str(file), '')
+    eq_(repr(file), '<ImageCacheFile: None>')
+
+    source_file = get_image_file()
+    file = LazyImageCacheFile('testspec', source=source_file)
+    file.name = 'a.jpg'
+    eq_(str(file), 'a.jpg')
+    eq_(repr(file), '<ImageCacheFile: a.jpg>')

tests/test_closing_fieldfiles.py

@@ -0,0 +1,25 @@
+from nose.tools import assert_false, assert_true
+
+from .models import Thumbnail
+from .utils import create_photo
+
+
+def test_do_not_leak_open_files():
+    instance = create_photo('leak-test.jpg')
+    source_file = instance.original_image
+    # Ensure the FieldFile is closed before generation
+    source_file.close()
+    image_generator = Thumbnail(source=source_file)
+    image_generator.generate()
+    assert_true(source_file.closed)
+
+
+def test_do_not_close_open_files_after_generate():
+    instance = create_photo('do-not-close-test.jpg')
+    source_file = instance.original_image
+    # Ensure the FieldFile is opened before generation
+    source_file.open()
+    image_generator = Thumbnail(source=source_file)
+    image_generator.generate()
+    assert_false(source_file.closed)
+    source_file.close()

tests/test_fields.py

@@ -5,7 +5,9 @@ from imagekit import forms as ikforms
 from imagekit.processors import SmartCrop
 from nose.tools import eq_
 from . import imagegenerators  # noqa
-from .models import ProcessedImageFieldModel, ImageModel
+from .models import (ProcessedImageFieldModel,
+                     ProcessedImageFieldWithSpecModel,
+                     ImageModel)
 from .utils import get_image_file
 
 
@@ -19,6 +21,16 @@ def test_model_processedimagefield():
     eq_(instance.processed.height, 50)
 
 
+def test_model_processedimagefield_with_spec():
+    instance = ProcessedImageFieldWithSpecModel()
+    file = File(get_image_file())
+    instance.processed.save('whatever.jpeg', file)
+    instance.save()
+
+    eq_(instance.processed.width, 100)
+    eq_(instance.processed.height, 60)
+
+
 def test_form_processedimagefield():
     class TestForm(forms.ModelForm):
         image = ikforms.ProcessedImageField(spec_id='tests:testform_image',
@@ -26,6 +38,7 @@ def test_form_processedimagefield():
 
         class Meta:
             model = ImageModel
+            fields = 'image',
 
     upload_file = get_image_file()
     file_dict = {'image': SimpleUploadedFile('abc.jpg', upload_file.read())}

tests/test_generateimage_tag.py

@@ -1,11 +1,12 @@
 from django.template import TemplateSyntaxError
 from nose.tools import eq_, assert_false, raises, assert_not_equal
 from . import imagegenerators  # noqa
-from .utils import render_tag, get_html_attrs
+from .utils import render_tag, get_html_attrs, clear_imagekit_cache
 
 
 def test_img_tag():
     ttag = r"""{% generateimage 'testspec' source=img %}"""
+    clear_imagekit_cache()
     attrs = get_html_attrs(ttag)
     expected_attrs = set(['src', 'width', 'height'])
     eq_(set(attrs.keys()), expected_attrs)
@@ -15,6 +16,7 @@ def test_img_tag():
 
 def test_img_tag_attrs():
     ttag = r"""{% generateimage 'testspec' source=img -- alt="Hello" %}"""
+    clear_imagekit_cache()
     attrs = get_html_attrs(ttag)
     eq_(attrs.get('alt'), 'Hello')
 
@@ -28,7 +30,7 @@ def test_dangling_html_attrs_delimiter():
 @raises(TemplateSyntaxError)
 def test_html_attrs_assignment():
     """
-    You can either use generateimage as an assigment tag or specify html attrs,
+    You can either use generateimage as an assignment tag or specify html attrs,
     but not both.
 
     """
@@ -42,11 +44,13 @@ def test_single_dimension_attr():
 
     """
     ttag = r"""{% generateimage 'testspec' source=img -- width="50" %}"""
+    clear_imagekit_cache()
     attrs = get_html_attrs(ttag)
     assert_false('height' in attrs)
 
 
 def test_assignment_tag():
-    ttag = r"""{% generateimage 'testspec' source=img as th %}{{ th.url }}"""
+    ttag = r"""{% generateimage 'testspec' source=img as th %}{{ th.url }}{{ th.height }}{{ th.width }}"""
+    clear_imagekit_cache()
     html = render_tag(ttag)
     assert_not_equal(html.strip(), '')

tests/test_no_extra_queries.py

@@ -0,0 +1,16 @@
+from nose.tools import assert_false
+from unittest.mock import Mock, PropertyMock, patch
+from .models import Photo
+
+
+def test_dont_access_source():
+    """
+    Touching the source may trigger an unneeded query.
+    See <https://github.com/matthewwithanm/django-imagekit/issues/295>
+
+    """
+    pmock = PropertyMock()
+    pmock.__get__ = Mock()
+    with patch.object(Photo, 'original_image', pmock):
+        photo = Photo()  # noqa
+        assert_false(pmock.__get__.called)

tests/test_optimistic_strategy.py

@@ -0,0 +1,49 @@
+from nose.tools import assert_true, assert_false
+from imagekit.cachefiles import ImageCacheFile
+from unittest.mock import Mock
+from .utils import create_image
+from django.core.files.storage import FileSystemStorage
+from imagekit.cachefiles.backends import Simple as SimpleCFBackend
+from imagekit.cachefiles.strategies import Optimistic as OptimisticStrategy
+
+
+class ImageGenerator(object):
+    def generate(self):
+        return create_image()
+
+    def get_hash(self):
+        return 'abc123'
+
+
+def get_image_cache_file():
+    storage = Mock(FileSystemStorage)
+    backend = SimpleCFBackend()
+    strategy = OptimisticStrategy()
+    generator = ImageGenerator()
+    return ImageCacheFile(generator, storage=storage,
+                          cachefile_backend=backend,
+                          cachefile_strategy=strategy)
+
+
+def test_no_io_on_bool():
+    """
+    When checking the truthiness of an ImageCacheFile, the storage shouldn't
+    peform IO operations.
+
+    """
+    file = get_image_cache_file()
+    bool(file)
+    assert_false(file.storage.exists.called)
+    assert_false(file.storage.open.called)
+
+
+def test_no_io_on_url():
+    """
+    When getting the URL of an ImageCacheFile, the storage shouldn't be
+    checked.
+
+    """
+    file = get_image_cache_file()
+    file.url
+    assert_false(file.storage.exists.called)
+    assert_false(file.storage.open.called)

tests/test_serialization.py

@@ -4,10 +4,40 @@ deserialized. This is important when using IK with Celery.
 
 """
 
-from .utils import create_photo, pickleback
+from imagekit.cachefiles import ImageCacheFile
+from .imagegenerators import TestSpec
+from .utils import create_photo, pickleback, get_unique_image_file, clear_imagekit_cache
 
 
 def test_imagespecfield():
+    clear_imagekit_cache()
     instance = create_photo('pickletest2.jpg')
     thumbnail = pickleback(instance.thumbnail)
     thumbnail.generate()
+
+
+def test_circular_ref():
+    """
+    A model instance with a spec field in its dict shouldn't raise a KeyError.
+
+    This corresponds to #234
+
+    """
+    clear_imagekit_cache()
+    instance = create_photo('pickletest3.jpg')
+    instance.thumbnail  # Cause thumbnail to be added to instance's __dict__
+    pickleback(instance)
+
+
+def test_cachefiles():
+    clear_imagekit_cache()
+    spec = TestSpec(source=get_unique_image_file())
+    file = ImageCacheFile(spec)
+    file.url
+    # remove link to file from spec source generator
+    # test __getstate__ of ImageCacheFile
+    file.generator.source = None
+    restored_file = pickleback(file)
+    assert file is not restored_file
+    # Assertion for #437 and #451
+    assert file.storage is restored_file.storage

tests/test_sourcegroups.py

@@ -0,0 +1,55 @@
+from django.core.files import File
+from imagekit.signals import source_saved
+from imagekit.specs.sourcegroups import ImageFieldSourceGroup
+from nose.tools import eq_
+from . models import AbstractImageModel, ImageModel, ConcreteImageModel
+from .utils import get_image_file
+
+
+def make_counting_receiver(source_group):
+    def receiver(sender, *args, **kwargs):
+        if sender is source_group:
+            receiver.count += 1
+    receiver.count = 0
+    return receiver
+
+
+def test_source_saved_signal():
+    """
+    Creating a new instance with an image causes the source_saved signal to be
+    dispatched.
+
+    """
+    source_group = ImageFieldSourceGroup(ImageModel, 'image')
+    receiver = make_counting_receiver(source_group)
+    source_saved.connect(receiver)
+    ImageModel.objects.create(image=File(get_image_file()))
+    eq_(receiver.count, 1)
+
+
+def test_no_source_saved_signal():
+    """
+    Creating a new instance without an image shouldn't cause the source_saved
+    signal to be dispatched.
+
+    https://github.com/matthewwithanm/django-imagekit/issues/214
+
+    """
+    source_group = ImageFieldSourceGroup(ImageModel, 'image')
+    receiver = make_counting_receiver(source_group)
+    source_saved.connect(receiver)
+    ImageModel.objects.create()
+    eq_(receiver.count, 0)
+
+
+def test_abstract_model_signals():
+    """
+    Source groups created for abstract models must cause signals to be
+    dispatched on their concrete subclasses.
+
+    """
+    source_group = ImageFieldSourceGroup(AbstractImageModel, 'original_image')
+    receiver = make_counting_receiver(source_group)
+    source_saved.connect(receiver)
+    ConcreteImageModel.objects.create(original_image=File(get_image_file()))
+    eq_(receiver.count, 1)

tests/test_thumbnail_tag.py

@@ -1,11 +1,12 @@
 from django.template import TemplateSyntaxError
 from nose.tools import eq_, raises, assert_not_equal
 from . import imagegenerators  # noqa
-from .utils import render_tag, get_html_attrs
+from .utils import render_tag, get_html_attrs, clear_imagekit_cache
 
 
 def test_img_tag():
     ttag = r"""{% thumbnail '100x100' img %}"""
+    clear_imagekit_cache()
     attrs = get_html_attrs(ttag)
     expected_attrs = set(['src', 'width', 'height'])
     eq_(set(attrs.keys()), expected_attrs)
@@ -15,6 +16,7 @@ def test_img_tag():
 
 def test_img_tag_attrs():
     ttag = r"""{% thumbnail '100x100' img -- alt="Hello" %}"""
+    clear_imagekit_cache()
     attrs = get_html_attrs(ttag)
     eq_(attrs.get('alt'), 'Hello')
 
@@ -40,7 +42,7 @@ def test_too_many_args():
 @raises(TemplateSyntaxError)
 def test_html_attrs_assignment():
     """
-    You can either use thumbnail as an assigment tag or specify html attrs,
+    You can either use thumbnail as an assignment tag or specify html attrs,
     but not both.
 
     """
@@ -50,17 +52,20 @@ def test_html_attrs_assignment():
 
 def test_assignment_tag():
     ttag = r"""{% thumbnail '100x100' img as th %}{{ th.url }}"""
+    clear_imagekit_cache()
     html = render_tag(ttag)
     assert_not_equal(html, '')
 
 
 def test_single_dimension():
     ttag = r"""{% thumbnail '100x' img as th %}{{ th.width }}"""
+    clear_imagekit_cache()
     html = render_tag(ttag)
     eq_(html, '100')
 
 
 def test_alternate_generator():
     ttag = r"""{% thumbnail '1pxsq' '100x' img as th %}{{ th.width }}"""
+    clear_imagekit_cache()
     html = render_tag(ttag)
     eq_(html, '1')

tests/test_utils.py

@@ -1,23 +0,0 @@
-from imagekit.exceptions import UnknownFormatError, UnknownExtensionError
-from imagekit.utils import extension_to_format, format_to_extension
-from nose.tools import eq_, raises
-
-
-def test_extension_to_format():
-    eq_(extension_to_format('.jpeg'), 'JPEG')
-    eq_(extension_to_format('.rgba'), 'SGI')
-
-
-def test_format_to_extension_no_init():
-    eq_(format_to_extension('PNG'), '.png')
-    eq_(format_to_extension('ICO'), '.ico')
-
-
-@raises(UnknownFormatError)
-def test_unknown_format():
-    format_to_extension('TXT')
-
-
-@raises(UnknownExtensionError)
-def test_unknown_extension():
-    extension_to_format('.txt')

tests/utils.py

@@ -1,10 +1,15 @@
 from bs4 import BeautifulSoup
 import os
-from django.conf import settings
+import shutil
 from django.core.files import File
 from django.template import Context, Template
+from imagekit.cachefiles.backends import Simple, CacheFileState
+from imagekit.conf import settings
 from imagekit.lib import Image, StringIO
+from imagekit.utils import get_cache
+from nose.tools import assert_true, assert_false
 import pickle
+from tempfile import NamedTemporaryFile
 from .models import Photo
 
 
@@ -14,12 +19,19 @@ def get_image_file():
 
     http://en.wikipedia.org/wiki/Lenna
     http://sipi.usc.edu/database/database.php?volume=misc&image=12
-
+    https://lintian.debian.org/tags/license-problem-non-free-img-lenna.html
+    https://github.com/libav/libav/commit/8895bf7b78650c0c21c88cec0484e138ec511a4b
     """
-    path = os.path.join(settings.MEDIA_ROOT, 'lenna.png')
+    path = os.path.join(settings.MEDIA_ROOT, 'reference.png')
     return open(path, 'r+b')
 
 
+def get_unique_image_file():
+    file = NamedTemporaryFile()
+    file.write(get_image_file().read())
+    return file
+
+
 def create_image():
     return Image.open(get_image_file())
 
@@ -52,4 +64,43 @@ def render_tag(ttag):
 
 
 def get_html_attrs(ttag):
-    return BeautifulSoup(render_tag(ttag)).img.attrs
+    return BeautifulSoup(render_tag(ttag), features="html.parser").img.attrs
+
+
+def assert_file_is_falsy(file):
+    assert_false(bool(file), 'File is not falsy')
+
+
+def assert_file_is_truthy(file):
+    assert_true(bool(file), 'File is not truthy')
+
+
+class DummyAsyncCacheFileBackend(Simple):
+    """
+    A cache file backend meant to simulate async generation.
+
+    """
+    is_async = True
+
+    def generate(self, file, force=False):
+        pass
+
+
+def clear_imagekit_cache():
+    cache = get_cache()
+    cache.clear()
+    # Clear IMAGEKIT_CACHEFILE_DIR
+    cache_dir = os.path.join(settings.MEDIA_ROOT, settings.IMAGEKIT_CACHEFILE_DIR)
+    if os.path.exists(cache_dir):
+        shutil.rmtree(cache_dir)
+
+
+def clear_imagekit_test_files():
+    clear_imagekit_cache()
+    for fname in os.listdir(settings.MEDIA_ROOT):
+        if fname != 'reference.png':
+            path = os.path.join(settings.MEDIA_ROOT, fname)
+            if os.path.isdir(path):
+                shutil.rmtree(path)
+            else:
+                os.remove(path)

tox.ini

@@ -1,37 +1,18 @@
 [tox]
 envlist =
-    py27-django14, py27-django13, py27-django12,
-    py26-django14, py26-django13, py26-django12
+    py38-django{master,30,22,21,20,111},
+    py37-django{master,30,22,21,20,111},
+    py36-django{master,30,22,21,20,111},
+    py35-django{21,20,111},
 
 [testenv]
 commands = python setup.py test
 
-[testenv:py27-django14]
-basepython = python2.7
 deps =
-    Django>=1.4,<1.5
-
-[testenv:py27-django13]
-basepython = python2.7
-deps =
-    Django>=1.3,<1.4
-
-[testenv:py27-django12]
-basepython = python2.7
-deps =
-    Django>=1.2,<1.3
-
-[testenv:py26-django14]
-basepython = python2.6
-deps =
-    Django>=1.4,<1.5
-
-[testenv:py26-django13]
-basepython = python2.6
-deps =
-    Django>=1.3,<1.4
-
-[testenv:py26-django12]
-basepython = python2.6
-deps =
-    Django>=1.2,<1.3
+    djangomaster: git+https://github.com/django/django.git@master#egg=Django
+    django30: Django>=3.0,<3.1
+    django22: Django>=2.2,<3.0
+    django21: Django>=2.1,<2.2
+    django20: Django>=2.0,<2.1
+    django111: Django>=1.11,<2.0
+    django{21,20,111}: django-nose==1.4.5