Example Application

Suppose we have the following basic django models (a fully executable version of this example can be found in pgpubsub.tests):

# models.py
class Author(models.Model):
    user = models.ForeignKey(
        User,
        on_delete=models.PROTECT,
        null=True,
    )
    name = models.TextField()


class Post(models.Model):
    content = models.TextField()
    date = models.DateTimeField()
    author = models.ForeignKey(
        Author,
        null=True,
        on_delete=models.SET_NULL,
        related_name='entries',
    )

Given these models, we’ll describe the mechanics of using the pgpubsub library to achieve the following aims (which are for illustrative purposes only):

• To asynchronously maintain a cache of how frequently Post objects are read per day.

• To define a postgres-trigger to ensure that, whenever an Author object is created, a Post object is asynchronously created for that author with the title “Test Post”.