Make a Django model read-only?
If you don't want an attempt to modify a record to fail silently:
def save(self, *args, **kwargs):
if self.pk:
(raise an exception)
super(YourModel, self).save(*args, **kwargs)
def delete(self, *args, **kwargs):
(raise an exception)
You can override the model's save method and check whether it's an existing entity, in which case you won't save any changes:
def save(self, *args, **kwargs):
if self.id is None:
super(ModelName, self).save(*args, **kwargs)
So in this example you only save the changes when the entity has not got an id
yet, which is only the case when it's a new entity that hasn't been inserted yet.
In addition to other solutions: If your main goal is to avoid write access from the admin, you can modify the used admin class so that nobody has an add/change permission:
class HistoryAdmin(admin.ModelAdmin):
def has_add_permission(self, request):
return False
def has_change_permission(self, request, obj=None):
return False
def has_delete_permission(self, request, obj=None):
return False
You can override the save method and not call super if you wanted to. That'd be a fairly easy way of accomplishing this.
# blatantly ripped the save from another answer, since I forgot to save original model
def save(self, *args, **kwargs):
if self.id is None:
super(ModelName, self).save(*args, **kwargs)
def delete(self, *args, **kwargs):
return
You should probably also raise an exception if a delete or update is attempting to occur instead of simply returning. You want to signal the user what is happening - that the behaviour isn't valid.