redditalgo.py

class Votable(BaseModel):
    points = db.IntegerProperty(default=1)
    score = db.FloatProperty()
    up_votes = db.StringListProperty() # contains user key_names
    down_votes = db.StringListProperty() # contains user key_names
    
    def update_score(self):
        """Adapted from reddit's algorithm
        http://code.reddit.com/browser/r2/r2/lib/db/sorts.py?rev=4778b17e939e119417cc5ec25b82c4e9a65621b2
        """
        td = self.created - datetime.datetime(1970, 1, 1)
        epoch_seconds = td.days * 86400 + td.seconds + (float(td.microseconds) / 1000000)
        order = math.log(max(abs(self.points), 1), 10)
        sign = 1 if self.points > 0 else -1 if self.points < 0 else 0
        seconds = epoch_seconds - 1134028003
        self.score = round(order + sign * seconds / 45000, 7)