Implement canonical HTML meta tag in the templates

[adiroiban]

To help with search engines, I think that the pydoctor templates should use a canonical tag to point to the latest version

https://docs.readthedocs.io/en/latest/canonical-urls.html

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With twisted we have this issue that when you search for twisted deferred API you get links like https://twisted.org/documents/10.1.0/api/twisted.internet.defer.Deferred.html

[tristanlatr]

Yes canonical urls is a good thing to have.

But also we should investigate the option of adding a « search in api docs » button from the readthedocs search bar.

[adiroiban]

But also we should investigate the option of adding a « search in api docs » button from the readthedocs search bar.

I think that this can be done in 2 steps:

1. Have pydoctor generate a dedicated search.html page that takes the search term from the URL. Search.html or api/index.html it doesn't matter. The important part to allow search input from the URL, not only via typing.

2. Create a raw HTML element on any Sphinx page with a form field that will make a GET to that page.