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POhow to model a follower stream in appengine?
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copied!<p>I am trying to design tables to buildout a follower relationship.</p> <p>Say I have a stream of 140char records that have user, hashtag and other text.</p> <p>Users follow other users, and can also follow hashtags.</p> <p>I am outlining the way I've designed this below, but there are two limitaions in my design. I was wondering if others had smarter ways to accomplish the same goal.</p> <p>The issues with this are</p> <ol> <li>The list of followers is copied in for each record</li> <li>If a new follower is added or one removed, 'all' the records have to be updated.</li> </ol> <p>The code </p> <pre><code>class HashtagFollowers(db.Model): """ This table contains the followers for each hashtag """ hashtag = db.StringProperty() followers = db.StringListProperty() class UserFollowers(db.Model): """ This table contains the followers for each user """ username = db.StringProperty() followers = db.StringListProperty() class stream(db.Model): """ This table contains the data stream """ username = db.StringProperty() hashtag = db.StringProperty() text = db.TextProperty() def save(self): """ On each save all the followers for each hashtag and user are added into a another table with this record as the parent """ super(stream, self).save() hfs = HashtagFollowers.all().filter("hashtag =", self.hashtag).fetch(10) for hf in hfs: sh = streamHashtags(parent=self, followers=hf.followers) sh.save() ufs = UserFollowers.all().filter("username =", self.username).fetch(10) for uf in ufs: uh = streamUsers(parent=self, followers=uf.followers) uh.save() class streamHashtags(db.Model): """ The stream record is the parent of this record """ followers = db.StringListProperty() class streamUsers(db.Model): """ The stream record is the parent of this record """ followers = db.StringListProperty() Now, to get the stream of followed hastags indexes = db.GqlQuery("""SELECT __key__ from streamHashtags where followers = 'myusername'""") keys = [k,parent() for k in indexes[offset:numresults]] return db.get(keys) </code></pre> <p>Is there a smarter way to do this?</p>

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