Merge branch 'streamfield-chooser-wip' into feature/streamfield

wagtail/wagtailadmin/blocks.py

@@ -330,7 +330,7 @@ class FieldBlock(Block):
         })
 
     def value_from_datadict(self, data, files, prefix):
-        return self.field.widget.value_from_datadict(data, files, prefix)
+        return self.to_python(self.field.widget.value_from_datadict(data, files, prefix))
 
     def clean(self, value):
         return self.field.clean(value)
@@ -349,12 +349,42 @@ class RichTextBlock(FieldBlock):
     def render_basic(self, value):
         return mark_safe('<div class="rich-text">' + expand_db_html(value) + '</div>')
 
-class PageChooserBlock(FieldBlock):
+
+class ChooserBlock(FieldBlock):
+    """Abstract superclass for fields that implement a chooser interface (page, image, snippet etc)"""
     @cached_property
     def field(self):
+        return ModelChoiceField(queryset=self.target_model.objects.all(), widget=self.widget)
+
+    def to_python(self, value):
+        if value is None or isinstance(value, self.target_model):
+            return value
+        else:
+            try:
+                return self.target_model.objects.get(pk=value)
+            except self.target_model.DoesNotExist:
+                return None
+
+    def get_prep_value(self, value):
+        if isinstance(value, self.target_model):
+            return value.id
+        else:
+            return value
+
+class PageChooserBlock(ChooserBlock):
+    @cached_property
+    def target_model(self):
         from wagtail.wagtailcore.models import Page  # TODO: allow limiting to specific page types
+        return Page
+
+    @cached_property
+    def widget(self):
         from wagtail.wagtailadmin.widgets import AdminPageChooser
-        return ModelChoiceField(queryset=Page.objects.all(), widget=AdminPageChooser)
+        return AdminPageChooser
+
+    def render_basic(self, value):
+        if value:
+            return format_html('<a href="{0}">{1}</a>', value.url, value.title)
 
 # =======
 # Chooser

wagtail/wagtailadmin/widgets.py

@@ -82,10 +82,14 @@ class AdminPageChooser(AdminChooser):
         self.target_content_type = content_type or ContentType.objects.get_for_model(Page)
 
     def render_html(self, name, value, attrs):
-        original_field_html = super(AdminPageChooser, self).render_html(name, value, attrs)
-
         model_class = self.target_content_type.model_class()
-        instance = self.get_instance(model_class, value)
+        if isinstance(value, model_class):
+            instance = value
+            value = value.pk
+        else:
+            instance = self.get_instance(model_class, value)
+
+        original_field_html = super(AdminPageChooser, self).render_html(name, value, attrs)
 
         return render_to_string("wagtailadmin/widgets/page_chooser.html", {
             'widget': self,
@@ -96,7 +100,11 @@ class AdminPageChooser(AdminChooser):
         })
 
     def render_js_init(self, id_, name, value):
-        page = Page.objects.get(pk=value) if value else None
+        model_class = self.target_content_type.model_class()
+        if isinstance(value, model_class):
+            page = value
+        else:
+            page = self.get_instance(model_class, value)
         parent = page.get_parent() if page else None
         content_type = self.target_content_type