First working version.

README.textile

@@ -0,0 +1,7 @@
+h1. youtube-api
+
+Google App Engine service to be used as the backend for some YQL tables.
+
+h2. http://youtube-api.appspot.com/video/[video_id]
+
+Gets video metadata by its id.

index.py

@@ -1,16 +1,64 @@
-import wsgiref.handlers
 from google.appengine.ext import webapp
+from google.appengine.ext.webapp.util import run_wsgi_app
 
-class MainPage(webapp.RequestHandler):
-  def get(self):
-    self.response.headers['Content-Type'] = 'text/plain'
-    self.response.out.write('Hello, App Engine!')
+from gdata.youtube.service import YouTubeService
+
+class VideoResource(webapp.RequestHandler):
+    def get(self):
+        self.response.headers['Content-Type'] = 'text/xml'
+        self.response.out.write('<?xml version="1.0" encoding="UTF-8"?>')
+
+        video_id = self.request.get('video_id', default_value='')
+        video = None
+        try:
+            yt = YouTubeService()
+            video = yt.GetYouTubeVideoEntry(video_id=video_id)
+        except Exception, e:
+            pass #will return empty result :)
+
+        if video:
+            self.response.out.write('<result>')
+            self.response.out.write('   <video>')
+            self.response.out.write('       <id>%s</id>' % video_id)
+            self.response.out.write('       <url><![CDATA[%s]]></url>' % video.media.player.url)
+            self.response.out.write('       <title><![CDATA[%s]]></title>' % video.title.text)
+            self.response.out.write('       <content><![CDATA[%s]]></content>' % video.content.text)
+            self.response.out.write('       <author><![CDATA[%s]]></author>' % video.author[0].name.text)
+            video.media.duration.seconds
+            self.response.out.write('       <comment_count>%d</comment_count>' % video.comments.feed_link[0].count_hint)
+
+            self.response.out.write('       <categories>')
+            for category in [category.label for category in video.category if category.label]:
+                self.response.out.write('           <category><![CDATA[%s]]></category>' % category)
+            self.response.out.write('       </categories>')
+
+            self.response.out.write('       <tags>')
+            if video.media.keywords.text
+                for tag in video.media.keywords.text.split(','):
+                    self.response.out.write('           <tag><![CDATA[%s]]></tag>' % tag)
+            self.response.out.write('       </tags>')
+
+            self.response.out.write('       <thumbnails>')
+            for thumbnail in video.media.thumbnail:
+                self.response.out.write('           <thumbnail width="%d" height="%d" time="">%s</thumbnail>' % (thumbnail.width, thumbnail.height, thumbnail.url, thumbnail.extension_attributes.get('time', '')))
+            self.response.out.write('       </thumbnails>')
+
+            self.response.out.write('       <files>')
+            for video_file in video.media.content:
+                self.response.out.write('           <file type="%s">%s</file>' % (video_file.type, video_file.url))
+            self.response.out.write('       </files>')
+
+            self.response.out.write('   </video>')
+            self.response.out.write('</result>')
+        else:
+            self.response.out.write('<result />')
+
+application = webapp.WSGIApplication(
+                                     [('/video/.*', VideoResource)],
+                                     debug=True)
 
 def main():
-  application = webapp.WSGIApplication(
-                                       [('/', MainPage)],
-                                       debug=True)
-  wsgiref.handlers.CGIHandler().run(application)
+    run_wsgi_app(application)
 
 if __name__ == "__main__":
-  main()
+    main()