From 8b6ba687e4ce0d3306cced4ef93be2438d7c0934 Mon Sep 17 00:00:00 2001
From: Matthew Tretter <matthew@exanimo.com>
Date: Thu, 2 Feb 2012 00:19:46 -0500
Subject: [PATCH] Commands for validating and invalidating the cache

---
 .../management/commands/ikcacheinvalidate.py  | 14 +++++++++
 .../management/commands/ikcachevalidate.py    | 30 ++++++++++++++++++
 imagekit/management/commands/ikflush.py       | 31 -------------------
 imagekit/utils.py                             | 31 +++++++++++++++++++
 4 files changed, 75 insertions(+), 31 deletions(-)
 create mode 100644 imagekit/management/commands/ikcacheinvalidate.py
 create mode 100644 imagekit/management/commands/ikcachevalidate.py
 delete mode 100644 imagekit/management/commands/ikflush.py

diff --git a/imagekit/management/commands/ikcacheinvalidate.py b/imagekit/management/commands/ikcacheinvalidate.py
new file mode 100644
index 0000000..2b6e915
--- /dev/null
+++ b/imagekit/management/commands/ikcacheinvalidate.py
@@ -0,0 +1,14 @@
+from django.core.management.base import BaseCommand
+from django.db.models.loading import cache
+from ...utils import invalidate_app_cache
+
+
+class Command(BaseCommand):
+    help = ('Invalidates the image cache for a list of apps.')
+    args = '[apps]'
+    requires_model_validation = True
+    can_import_settings = True
+
+    def handle(self, *args, **options):
+        apps = args or cache.app_models.keys()
+        invalidate_app_cache(apps)
diff --git a/imagekit/management/commands/ikcachevalidate.py b/imagekit/management/commands/ikcachevalidate.py
new file mode 100644
index 0000000..fc9a9c0
--- /dev/null
+++ b/imagekit/management/commands/ikcachevalidate.py
@@ -0,0 +1,30 @@
+from optparse import make_option
+from django.core.management.base import BaseCommand
+from django.db.models.loading import cache
+from ...utils import validate_app_cache
+
+
+class Command(BaseCommand):
+    help = ('Validates the image cache for a list of apps.')
+    args = '[apps]'
+    requires_model_validation = True
+    can_import_settings = True
+
+    option_list = BaseCommand.option_list + (
+        make_option('--force',
+            dest='force_revalidation',
+            action='store_true',
+            default=False,
+            help='Invalidate each image file before validating it, thereby'
+                    ' ensuring its revalidation. This is very similar to'
+                    ' running ikcacheinvalidate and then running'
+                    ' ikcachevalidate; the difference being that this option'
+                    ' causes files to be invalidated and validated'
+                    ' one-at-a-time, whereas running the two commands in series'
+                    ' would invalidate all images before validating any.'
+        ),
+    )
+
+    def handle(self, *args, **options):
+        apps = args or cache.app_models.keys()
+        validate_app_cache(apps, options['force_revalidation'])
diff --git a/imagekit/management/commands/ikflush.py b/imagekit/management/commands/ikflush.py
deleted file mode 100644
index de4be3f..0000000
--- a/imagekit/management/commands/ikflush.py
+++ /dev/null
@@ -1,31 +0,0 @@
-"""
-Flushes and re-caches all images under ImageKit.
-
-"""
-from django.db.models.loading import cache
-from django.core.management.base import BaseCommand
-from .utils import get_spec_files
-
-
-class Command(BaseCommand):
-    help = ('Clears all ImageKit cached files.')
-    args = '[apps]'
-    requires_model_validation = True
-    can_import_settings = True
-
-    def handle(self, *args, **options):
-        return flush_cache(args, options)
-
-
-def flush_cache(apps, options):
-    apps = [a.strip(',') for a in apps]
-    if apps:
-        for app_label in apps:
-            app = cache.get_app(app_label)
-            for model in [m for m in cache.get_models(app)]:
-                print 'Flushing cache for "%s.%s"' % (app_label, model.__name__)
-                for obj in model.objects.order_by('-pk'):
-                    for f in get_spec_files(obj):
-                        f.invalidate()
-    else:
-        print 'Please specify one or more app names'
diff --git a/imagekit/utils.py b/imagekit/utils.py
index 02e71c1..305bdd4 100644
--- a/imagekit/utils.py
+++ b/imagekit/utils.py
@@ -1,6 +1,7 @@
 import tempfile
 import types
 
+from django.db.models.loading import cache
 from django.utils.functional import wraps
 
 from imagekit.lib import Image, ImageFile
@@ -134,3 +135,33 @@ def format_to_extension(format):
     if not extension:
         raise UnknownFormatError(format)
     return extension
+
+
+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
+
+
+def invalidate_app_cache(apps):
+    for model in _get_models(apps):
+        print 'Invalidating cache for "%s.%s"' % (model._meta.app_label, model.__name__)
+        for obj in model._default_manager.order_by('-pk'):
+            for f in get_spec_files(obj):
+                f.invalidate()
+
+
+def validate_app_cache(apps, force_revalidation=False):
+    for model in _get_models(apps):
+        for obj in model._default_manager.order_by('-pk'):
+            model_name = '%s.%s' % (model._meta.app_label, model.__name__)
+            if force_revalidation:
+                print 'Invalidating & validating cache for "%s"' % model_name
+            else:
+                print 'Validating cache for "%s"' % model_name
+            for f in get_spec_files(obj):
+                if force_revalidation:
+                    f.invalidate()
+                f.validate()