Content Types
Content Types
it's a built in app that keeps track of models from the installed apps of your Django application. And one of the use cases of theContentTypesis to create generic relationships between models.
GenericForeignKey
If we want to store the user activities with these models like "created User, created Project, created Task" in a timeline, we have to create all the three models(User, Project, Task)as 'ForeignKey' fields. This is not a good programming practice. To overcome this, Django's content types frameworkprovides a special field type (GenericForeignKey) which allows the relationship to be with any model.
Using 'GenericForeignKey':
- Give your model aForeignKeytoContentType. The usual name for this field is "content_type".
- Give your model a field that can store primary key values from the models you'll be relating to. For most models, this means aPositiveIntegerField. The usual name for this field is "object_id".
- Give your model aGenericForeignKey, and pass it the names of the two fields described above. If these fields are named "content_type" and "object_id", you can omit this -- those are the default field names GenericForeignKey will look for.
References
Generic Relations - https://simpleisbetterthancomplex.com/tutorial/2016/10/13/how-to-use-generic-relations.html
https://micropyramid.com/blog/understanding-genericforeignkey-in-django
https://axiacore.com/blog/how-use-genericforeignkey-django