ExtendedDefaultRouter root view is polluted

[cancan101]

I am using ExtendedDefaultRouter with nested routes. Right now my root view is being polluted by the sub items:

GET /api/

{
    "people": "http://127.0.0.1:8000/api/people/", 
    "people/(?P<parent_lookup_person__uuid>[^/.]+)/tests": "http://127.0.0.1:8000/api/tests/",
    "tests": "http://127.0.0.1:8000/api/tests/"
}

[kevin-brown]

This is because your tests and people/(?P<parent_lookup_person__uuid>[^/.]+)/tests views both have the same base_name of test. You can tell because both of them are (incorrectly) pointing to the same url, and the first one is not triggering an error.

The ExtendedDefaultRouter depends on the first one triggering a reverse error, so it can be excluded from the output.

[cancan101]

I saw that the URL was duplicated. This does not fully explain the issue, however.

In[5]: reverse('test-list')
Out[5]: '/api/tests/'

In[7]:  reverse('test-list', kwargs={'parent_lookup_person__uuid':'alex'})
Out[7]: '/api/people/alex/tests/'

[cancan101]

Either way, the nested item should not be exposed at the top level (ie root view). The only reason this works when changing the base name is:

                for key, url_name in api_root_dict.items():
                    try:
                        ret[key] = reverse(url_name, request=request, format=format)
                    except NoReverseMatch:
                        pass

where key is people/(?P<parent_lookup_person__uuid>[^/.]+)/tests and url_name is <base_name>-list.

Changing the base_name to something else causes NoReverseMatch to be raised so the item is silently hidden from the root view.

There is no reason that base_name should not be able to be set to the same value for both levels.

Right now I am trying to move to drf-extensions from https://github.com/alanjds/drf-nested-routers and I had been able to use the same base_name without an issue before.

[cancan101]

The issue here is that register called on NestedRegistryItem adds to the registry of the underlying router rather than keeping a separate list of sub URLs.

[kevin-brown]

This does not fully explain the issue, however...

Yes, multiple routes can share the same name and take in different arguments.

Changing the base_name to something else causes NoReverseMatch to be raised so the item is silently hidden from the root view.

This is intentional and it was added in #14. I don't know of a better way to handle it, but I'm sure a pull request would be reviewed if it came in.

Right now I am trying to move to drf-extensions from https://github.com/alanjds/drf-nested-routers and I had been able to use the same base_name without an issue before.

If I remember correctly, drf-nested-routers did not support the DefaultRouter and using the one provided by DRF should have had the same issue.

[cancan101]

@kevin-brown I think the root cause for all of this is: #57 (comment)

That is implicitly how drf-extensions deals with the issue: it does NOT add all of the routes to the base router but required you to add those routers individually.

[cancan101]

@kevin-brown Any more thoughts on this?

[cancan101]

@kevin-brown Thoughts?

[kevin-brown]

@cancan101 looks like it's up to @chibisov.

For what it's worth, you'd have this issue without the custom router now that DRF also has the try...except code in place.

[cancan101]

@kevin-brown:

The issue here is that register called on NestedRegistryItem adds to the registry of the underlying router rather than keeping a separate list of sub URLs.

This is different from how drf-nested-routers works where each nested router keeps track of the URLs (routes) at its level.

[auvipy]

closing