"Merge pull request #57 from Code4SA/django-manifest\n\nIntegrate wit…

…h Django's ManifestStaticFileStorage"

django_assets/management/commands/assets.py

@@ -32,7 +32,7 @@
                               GenericArgparseImplementation)
 from django_assets.env import get_env, autoload
 from django_assets.loaders import get_django_template_dirs, DjangoLoader
-
+from django_assets.manifest import DjangoManifest  # noqa: enables the --manifest django option
 
 try:
     from django.core.management import LaxOptionParser

django_assets/manifest.py

@@ -0,0 +1,59 @@
+import os
+
+from webassets.version import Manifest
+
+try:
+    from django.contrib.staticfiles.storage import ManifestStaticFilesStorage
+
+    class DjangoManifest(Manifest):
+        """Stores version data in Django's ManifestStaticFileStorage.
+
+        Requires Django 1.7 or later.
+        """
+
+        id = 'django'
+
+        def __init__(self, *a, **kw):
+            try:
+                import json
+            except ImportError:
+                import simplejson as json
+            self.json = json
+            self.storage = ManifestStaticFilesStorage()
+            self._load_manifest()
+
+        def remember(self, bundle, ctx, version):
+            output_filename = bundle.resolve_output(ctx, version=version)
+            output_filename = os.path.relpath(output_filename, ctx.directory)
+            source_filename = self.name_without_hash(bundle.output)
+
+            self.storage.hashed_files[source_filename] = output_filename
+            self._save_manifest()
+
+        def query(self, bundle, ctx):
+            if ctx.auto_build:
+                self._load_manifest()
+
+            source_filename = self.name_without_hash(bundle.output)
+            output = self.storage.hashed_files.get(source_filename, None)
+            if output:
+                # foo.hash.js
+                name_with_hash, ext = os.path.splitext(output)
+                output = os.path.splitext(name_with_hash)[1]
+
+            return output
+
+        def name_without_hash(self, filename):
+            name_with_hash, ext = os.path.splitext(filename)
+            name = os.path.splitext(name_with_hash)[0]
+            return name + ext
+
+        def _load_manifest(self):
+            self.storage.load_manifest()
+
+        def _save_manifest(self):
+            self.storage.save_manifest()
+
+except ImportError:
+    class DjangoManifest(object):
+        pass

docs/staticfiles.rst

@@ -92,3 +92,16 @@ define an ``ASSETS_ROOT`` setting that points to a different directory
 then ``STATIC_ROOT``. Only then will ``collectstatic`` be able to find the
 output files created with ``./manage.py build --parse-templates``, and
 process them into ``STATIC_ROOT``, like any other static file.
+
+``ManifestStaticFileStorage`` or White Noise
+--------------------------------------------
+
+If you are using Django's ``ManifestStaticFilesStorage`` or White Noise's
+``GzipManifestStaticFilesStorage`` then you must build your assets after
+calling ``collectstatic`` using the ``--manifest django`` option::
+
+    ./manage.py assets build --manifest django
+    
+This will add the built assets to Django's static files manifest. In particular,
+this ensures that White Noise realises they are cacheable static files and
+will add appropriate far-future expiry headers when serving them.