Add thumbnail generation support

src/dcow/app.py

@@ -1,11 +1,12 @@
 from milla.dispatch import routing
-from . import gallery
+from . import gallery, thumbnails
 import os
 import milla.util
 
 
 DEFAULT_CONFIG = {
     'gallery.screenshot_dir': 'screenshots',
+    'gallery.thumbnail_dir': 'thumbnails',
 }
 
 
@@ -28,3 +29,4 @@ class Application(milla.Application):
         self.dispatcher = r = routing.Router()
 
         r.add_route('/', gallery.GalleryController())
+        r.add_route('/thumbnails/{image}', thumbnails.ThumbnailController())

src/dcow/templates/gallery.html.j2

@@ -18,7 +18,7 @@
 {% for image in images %}
 <div class="column">
 <a href="{{ static('screenshots/' + image) }}">
-<img src="{{ static('screenshots/' + image) }}"
+<img class="thumbnail" src="{{ url('/thumbnails/' + image) }}"
   alt="{{ image.rsplit('.', 1)[0] }}" />
 </a>
 </div>

src/dcow/thumbnails.py

@@ -0,0 +1,34 @@
+from PIL import Image, ImageOps
+from milla import controllers
+import milla
+import os
+import webob.static
+
+
+class ThumbnailController(milla.controllers.HTTPVerbController):
+
+    CROP_SIZE = (1920, 1080)
+    THUMB_SIZE = (262, 148)
+
+    def GET(self, request, image):
+        thumb_dir = request.config['gallery.thumbnail_dir']
+        image_dir = request.config['gallery.screenshot_dir']
+        screenshot = os.path.join(image_dir, image)
+        thumbnail = os.path.join(thumb_dir, image)
+        try:
+            s_st = os.stat(screenshot)
+        except OSError:
+            raise milla.HTTPNotFound
+        try:
+            t_st = os.stat(thumbnail)
+        except OSError:
+            t_st = None
+        if not t_st or t_st.st_mtime < s_st.st_mtime:
+            self.generate_thumbnail(screenshot, thumbnail)
+        return webob.static.FileApp(thumbnail)
+
+    def generate_thumbnail(self, screenshot, thumbnail):
+        image = Image.open(screenshot)
+        thumb = ImageOps.fit(image, self.CROP_SIZE)
+        thumb.thumbnail(self.THUMB_SIZE)
+        thumb.save(thumbnail)