Add maintenace view to clear the document image cache

apps/documents/__init__.py

@@ -85,6 +85,7 @@ document_clear_transformations = {'text': _(u'clear transformations'), 'view': '
 document_multiple_clear_transformations = {'text': _(u'clear transformations'), 'view': 'document_multiple_clear_transformations', 'famfam': 'page_paintbrush', 'permissions': [PERMISSION_DOCUMENT_TRANSFORM]}
 document_print = {'text': _(u'print'), 'view': 'document_print', 'args': 'object.id', 'famfam': 'printer', 'permissions': [PERMISSION_DOCUMENT_VIEW]}
 document_history_view = {'text': _(u'history'), 'view': 'history_for_object', 'args': ['"documents"', '"document"', 'object.id'], 'famfam': 'book_go', 'permissions': [PERMISSION_DOCUMENT_VIEW]}
+document_clear_image_cache = {'text': _(u'Clear the document image cache'), 'view': 'document_clear_image_cache', 'famfam': 'camera_delete', 'permissions': [PERMISSION_DOCUMENT_TOOLS], 'description': _(u'Clear the graphics representations used to speed up the documents\' display and interactive transformations results.')}
 
 document_page_transformation_list = {'text': _(u'page transformations'), 'class': 'no-parent-history', 'view': 'document_page_transformation_list', 'args': 'page.pk', 'famfam': 'pencil_go', 'permissions': [PERMISSION_DOCUMENT_TRANSFORM]}
 document_page_transformation_create = {'text': _(u'create new transformation'), 'class': 'no-parent-history', 'view': 'document_page_transformation_create', 'args': 'page.pk', 'famfam': 'pencil_add', 'permissions': [PERMISSION_DOCUMENT_TRANSFORM]}
@@ -158,7 +159,7 @@ register_links(['document_page_transformation_edit', 'document_page_transformati
 
 register_diagnostic('documents', _(u'Documents'), document_missing_list)
 
-register_maintenance_links([document_find_all_duplicates, document_update_page_count], namespace='documents', title=_(u'documents'))
+register_maintenance_links([document_find_all_duplicates, document_update_page_count, document_clear_image_cache], namespace='documents', title=_(u'documents'))
 
 #def document_exists(document):
 #    try:

apps/documents/models.py

@@ -92,6 +92,13 @@ class Document(models.Model):
         object_id_field='object_pk'
     )
 
+    @staticmethod
+    def clear_image_cache():
+        for the_file in os.listdir(CACHE_PATH):
+            file_path = os.path.join(CACHE_PATH, the_file)
+            if os.path.isfile(file_path):
+                os.unlink(file_path)
+
     class Meta:
         verbose_name = _(u'document')
         verbose_name_plural = _(u'documents')

apps/documents/urls.py

@@ -37,6 +37,7 @@ urlpatterns = patterns('documents.views',
     url(r'^multiple/clear_transformations/$', 'document_multiple_clear_transformations', (), 'document_multiple_clear_transformations'),
     url(r'^duplicates/list/$', 'document_find_all_duplicates', (), 'document_find_all_duplicates'),
     url(r'^maintenance/update_page_count/$', 'document_update_page_count', (), 'document_update_page_count'),
+    url(r'^maintenance/clear_image_cache/$', 'document_clear_image_cache', (), 'document_clear_image_cache'),
 
     url(r'^page/(?P<document_page_id>\d+)/$', 'document_page_view', (), 'document_page_view'),
     url(r'^page/(?P<document_page_id>\d+)/text/$', 'document_page_text', (), 'document_page_text'),

apps/documents/views.py

@@ -1121,3 +1121,24 @@ def document_type_filename_create(request, document_type_id):
         'document_type': document_type,
     },
     context_instance=RequestContext(request))
+    
+    
+def document_clear_image_cache(request):
+    check_permissions(request.user, [PERMISSION_DOCUMENT_TOOLS])
+
+    previous = request.POST.get('previous', request.GET.get('previous', request.META.get('HTTP_REFERER', '/')))
+
+    if request.method == 'POST':
+        try:
+            Document.clear_image_cache()
+            messages.success(request, _(u'Document image cache cleared successfully'))
+        except Exception, msg:
+            messages.error(request, _(u'Error clearing document image cache; %s') % msg)
+            
+        return HttpResponseRedirect(previous)
+
+    return render_to_response('generic_confirm.html', {
+        'previous': previous,
+        'title': _(u'Are you sure you wish to clear the document image cache?'),
+        'form_icon': u'camera_delete.png',
+    }, context_instance=RequestContext(request))