TypeError: Object of type datetime is not JSON serializable

[Alexeino]

If the message contains the datetime.datetime fields it isn't able to load message in django admin task detail view. Results into TypeError.
I had to override the TaskAdmin.message_details to do something like this
json.dumps(instance.message._asdict(), indent=4, cls=DjangoJSONEncoder) # Using DjangoJSONEncoder here
and unregister and register with this CustomTaskAdmin.

Any other ways to mitigate it ?

[andrewgy8]

Hey @Alexeino !

Are you using a custom encoder? Any details on how you are calling the send method?

Im unable to reproduce this, as dramatiq expectedly throws an error when passing a datetime object like datetime.now() to send.

[Alexeino]

Actually Issue arises, when django_dramatiq.admin.TaskAdmin tries to produce message_details

which is then displayed in task details in django admin details view. It actually is a display error where it is not able to convert instance.message if this message has a datetime.datetime type of field.
So when somebody accesses a Task detail in django admin url like /system/admin/django_dramatiq/task/8rthr4502-c715-4a96-b41f-b77c75hggc12e/change/ , raises TypeError: Object of type datetime is not JSON serializable.
So to mitigate it I had to dome something like this.

admin.site.unregister(Task)

@admin.register(Task)
class CustomTaskAdmin(TaskAdmin):
    def message_details(self, instance):
        """
        Overriding TaskAdmin from django_dramatiq to avoid Serialization Errors for datetime objects.
        In future if fixed by library, this can be removed.
        """
        message_details = json.dumps(instance.message._asdict(), indent=4, cls=DjangoJSONEncoder)  # noqa: SLF001
        return mark_safe("<pre>%s</pre>" % message_details)

So here I am providing DjangoJSONEncoder which fixes it.
Not sure if it's best option but it wokred for me

[andrewgy8]

Which version of django_dramatiq are you running?