ModelFormMixing's handling of "success_url" is inconsistent with old generic view behaviour

[Gabriel Grant]

Handling of "success_url" in ModelFormMixing seems to be inconsistent with how "get_absolute_url" is handled in views.generic.create_update.redirect()

In old generic views, the url could be a format string into which the object's fields would be interpolated. But that doesn't happed in ModelFormMixin: form_valid() just redirects to the result of get_success_url() (which doesn't do the interpolation)

This inconsistency should be dealt with by either:

1. documenting the discrepency in ​here (presumably with the suggestion that the reader override the "get_success_url()" method to implement the interpolation)

2. patching ModelFormMixin.get_success_url() to be consistent with old generic view handling and document the behaviour ​here

I prefer the latter, but the behaviour change could be a design decision (which I'm certainly not qualified to override :). Let me know, and I can prepare a patch.

Also, as an aside, it seems that redirecting back to the POSTed form would be a better last-resort, rather than throwing an ImproperlyConfigured error.

Comments?

[Gabriel Grant]

patch implements solution #2. Includes tests & docs

[Russell Keith-Magee]

Patch looks good, mod some minor PEP8 stuff that can easily get cleaned up prior to commit.

As for the aside -- sounds like a good idea to me, but it needs a separate ticket, and a patch that implements a get_absolute_url() solution that defers to success_url if it is provided.

[Russell Keith-Magee]

(In [14808]) Fixed #14803 -- Corrected an inconsistency in redirection handling between old-style generic views and class-based views. Thanks to gg for the report and patch.

[Jacob]

Milestone 1.3 deleted