Use different setting for footer api url

[stsewd]

Currently we use 'api_host' in our js to call the footer api.
I'm making a separate setting just for the footer api.
This is to allow us to proxy the footer api from the same domain that
is serving the docs (this is useful for .com).

We can't proxy the whole api from the serve app because there are some
places where we call reverse, and on the serve app we don't have
access to all urls (like project dashboard).

We need to publish the sphinx-extension with this change first.

Are we ok with this? Other option is to pass the whole endpoint (including /api/v2/footer_html/)

[ericholscher]

I don't like a one-off setting like this. I'd much prefer a pattern that is more generic that we can move to over time. I think something like proxied_api_host or similar, so that we can reuse it later if we start proxying more API's on the users domains.

[stsewd]

@ericholscher done. PR for the sphinx-ext readthedocs/readthedocs-sphinx-ext#77

Note: the ext should be released first, otherwise it wouldn't set the proxied_api_host attr on the js object.

[humitos]

If I understand correctly, the idea here is to hit the endpoint of the footer_api from the serve instance instead of the main instance (so we can apply authentication) --is that correct? In case it is, don't we need to use a different path as well that includes the DOC_PATH_PREFIX?

I'm thinking that proxied_api_host will be docs.company.org and the full URL for the endpoint should be https://docs.company.org/_/api/v2/footer_html/.

Unlikely, but possible, https://docs.company.org/api/v2/footer_html/ could be a valid page.

[stsewd]

@humitos yes is to hit the api from the serve instance. For .org it would point to the public api on readthedocs.org/api/. For .com it would be an absolute url without domain and using the DOC_PATH_PREFIX. So, for .com it would be /_/ -> foo.com/_/api/v2/...

[humitos]

The changes look good.

It would be good to have some explanation in code comments about this because it's hard to differentiate api_host and proxied_api_host just reading the code.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[ericholscher]

This looks 💯

[ericholscher]

We need to wait to merge this until the backend is working, correct?

Edit: I guess not, since it defaults to RTD.org, so it should keep working.

[stsewd]

@ericholscher this one can be reviewed/merged now readthedocs/readthedocs-sphinx-ext#77