Generating RSS feed under Google App Engine

Question

I want to provide rss feed under google app engine/python.

I've tried to use usual request handler and generate xml response. When I access the feed url directly, I can see the feed correctly, however, when I'm trying to subscribe to the feed in google reader, it says that

'The feed being requested cannot be found.'

I wonder whether this approach is right. I was considering using a static xml file and updating it by cron jobs. But while GAE doesn't support file i/o, this approach seems not going to work.

How to solve this? Thanks!

my guess would be you need to probably set the correct content type in the response headers in order for the browser to recognize it as an rss feed. but I'm too lazy at the moment to look up what the content type is to give you a formal answer. — Tom Willis

Niklas Rosencrantz Niklas Rosencrantz · Accepted Answer · 2011-12-14T18:13:15

There're 2 solutions I suggest:

GAE-REST you can just add to your project and configure and it will make RSS for you but the project is old and no longer maintained.

Do like I do, use a template to write a list to and like this I could succeed generating RSS (GeoRSS) that can be read via google reader where template is:

<title>{{host}}</title>
<link href="http://{{host}}" rel="self"/>
<id>http://{{host}}/</id>
<updated>2011-09-17T08:14:49.875423Z</updated>
<generator uri="http://{{host}}/">{{host}}</generator>

{% for entity in entities %}

<entry>

<title><![CDATA[{{entity.title}}]]></title>
<link href="http://{{host}}/vi/{{entity.key.id}}"/>
<id>http://{{host}}/vi/{{entity.key.id}}</id>
<updated>{{entity.modified.isoformat}}Z</updated>
<author><name>{{entity.title|escape}}</name></author>
<georss:point>{{entity.geopt.lon|floatformat:2}},{{entity.geopt.lat|floatformat:2}}</georss:point>
<published>{{entity.added}}</published>
<summary type="xhtml"><div xmlns="http://www.w3.org/1999/xhtml">{{entity.text|escape}}</div>
</summary>

</entry>

{% endfor %}

</feed>

My handler is (you can also do this with python 2.7 as just a function outside a handler for a more minimal solution):

class GeoRSS(webapp2.RequestHandler):

    def get(self):
        start = datetime.datetime.now() - timedelta(days=60)
        count = (int(self.request.get('count'
                 )) if not self.request.get('count') == '' else 1000)
        try:
            entities = memcache.get('entities')
        except KeyError:
            entity = Entity.all().filter('modified >',
                                  start).filter('published =',
                    True).order('-modified').fetch(count)
        memcache.set('entities', entities)
        template_values = {'entities': entities, 'request': self.request,
                           'host': os.environ.get('HTTP_HOST',
                           os.environ['SERVER_NAME'])}
        dispatch = 'templates/georss.html'
        path = os.path.join(os.path.dirname(__file__), dispatch)
        output = template.render(path, template_values)
        self.response.headers['Cache-Control'] = 'public,max-age=%s' \
            % 86400
        self.response.headers['Content-Type'] = 'application/rss+xml'
        self.response.out.write(output)

I hope some of this works for you, both ways worked for me.

Generating RSS feed under Google App Engine

3 Answers