Themes REST API endpoint: Add stylesheet_uri and template_uri fields to the response

[andrewserong]

Based on an idea from @ramonjd and @noisysocks in WordPress/gutenberg#60578, this PR explores adding stylesheet_uri and template_uri fields to the API response for the themes endpoint. The goal being to expose the URI of the directory for a theme (or its parent theme when dealing with child themes) so that theme relative URIs can be constructed by consumers of this endpoint. An example use case is in WordPress/gutenberg#60578

A quick way to test this is to apply the PR and then open up the post editor and run the following from the console:

wp.apiFetch( { path: '/wp/v2/themes/twentytwentyfour' } );

In the API response, you should see stylesheet and template uris in the response:

Trac ticket: https://core.trac.wordpress.org/ticket/61021

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[andrewserong]

I've updated and added tests. A few questions for anyone reviewing:

• These two fields refer to the directory, should that be in the name as well, or is stylesheet_uri and template_uri straightforward enough?
• Other fields have raw and rendered versions of the URI (i.e. author_uri and theme_uri are objects with raw and rendered keys). Should we do that for these, too? My assumption is that since these new fields are meant to be used to construct URIs rather than to be displayed, the answer would be no. But for consistency it might be confusing if these are just strings.
• Are these values safe to expose in this way? I.e. if you have permission to get all the other data from this endpoint, is this extra data consistent with the current permissions / capabilities?

[TimothyBJacobs]

It seems unexpected that this is not applying the stylesheet_directory_uri because it isn't using the global get_stylesheet_directory_uri function. We probably need to alter how the response is prepared if it's the current theme or not. See the is_same_theme helper.

[andrewserong]

Thanks for the review @TimothyBJacobs!

It seems unexpected that this is not applying the stylesheet_directory_uri because it isn't using the global get_stylesheet_directory_uri function

Good catch! I've updated the logic in b1dd7ff so that it calls the global functions for both the template directory uri and the stylesheet directory uri if the current theme matches the requested theme, so I believe this should hook into those filters now. I'm not very familiar with this part of the code base, though, so do let me know if there's anything off with this approach.

Thanks!

[noisysocks]

Gave this for a spin locally by checking the branch out and creating a child theme of TT4 called tt4-child:

% http -a "admin:password" GET http://localhost:8889/wp-json/wp/v2/themes | jq '.[] | { stylesheet, status, template_uri, stylesheet_uri }'
{
  "stylesheet": "tt4-child",
  "status": "active",
  "template_uri": "http://localhost:8889/wp-content/themes/twentytwentyfour",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/tt4-child"
}
{
  "stylesheet": "twentyeleven",
  "status": "inactive",
  "template_uri": "http://localhost:8889/wp-content/themes/twentyeleven",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/twentyeleven"
}
{
  "stylesheet": "twentyfifteen",
  "status": "inactive",
  "template_uri": "http://localhost:8889/wp-content/themes/twentyfifteen",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/twentyfifteen"
}
{
  "stylesheet": "twentyfourteen",
  "status": "inactive",
  "template_uri": "http://localhost:8889/wp-content/themes/twentyfourteen",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/twentyfourteen"
}
{
  "stylesheet": "twentynineteen",
  "status": "inactive",
  "template_uri": "http://localhost:8889/wp-content/themes/twentynineteen",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/twentynineteen"
}
{
  "stylesheet": "twentyseventeen",
  "status": "inactive",
  "template_uri": "http://localhost:8889/wp-content/themes/twentyseventeen",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/twentyseventeen"
}
{
  "stylesheet": "twentysixteen",
  "status": "inactive",
  "template_uri": "http://localhost:8889/wp-content/themes/twentysixteen",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/twentysixteen"
}
{
  "stylesheet": "twentyten",
  "status": "inactive",
  "template_uri": "http://localhost:8889/wp-content/themes/twentyten",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/twentyten"
}
{
  "stylesheet": "twentythirteen",
  "status": "inactive",
  "template_uri": "http://localhost:8889/wp-content/themes/twentythirteen",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/twentythirteen"
}
{
  "stylesheet": "twentytwelve",
  "status": "inactive",
  "template_uri": "http://localhost:8889/wp-content/themes/twentytwelve",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/twentytwelve"
}
{
  "stylesheet": "twentytwenty",
  "status": "inactive",
  "template_uri": "http://localhost:8889/wp-content/themes/twentytwenty",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/twentytwenty"
}
{
  "stylesheet": "twentytwentyfour",
  "status": "inactive",
  "template_uri": "http://localhost:8889/wp-content/themes/twentytwentyfour",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/twentytwentyfour"
}
{
  "stylesheet": "twentytwentyone",
  "status": "inactive",
  "template_uri": "http://localhost:8889/wp-content/themes/twentytwentyone",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/twentytwentyone"
}
{
  "stylesheet": "twentytwentythree",
  "status": "inactive",
  "template_uri": "http://localhost:8889/wp-content/themes/twentytwentythree",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/twentytwentythree"
}
{
  "stylesheet": "twentytwentytwo",
  "status": "inactive",
  "template_uri": "http://localhost:8889/wp-content/themes/twentytwentytwo",
  "stylesheet_uri": "http://localhost:8889/wp-content/themes/twentytwentytwo"
}

[noisysocks]

Code LGTM to me too. Nice work 👍

[ramonjd]

Would it worth testing inactive themes as well after b1dd7ff?

[andrewserong]

Oh, thanks for spotting that! I've updated the tests in b444489 to include both active and inactive themes in the response, and loop over the results to check against the global function or the method on the theme object, depending on the status.

Let me know if you think it's better to split into separate tests, though.

[ramonjd]

Thanks for updating! LGTM

The only thing I'd do is add a message as the third argument to the assertSames so that failing tests return something meaningful.

[andrewserong]

Good point 👍

Added in: 23cae05. Happy to tweak the wording if need be.

[ramonjd]

Thanks for working on this 🙇🏻 LGTM!

[andrewserong]

Thanks for all the reviews, everyone! I'll be AFK over the next week, so in case there's any further feedback, I won't be able to get to it until the week after. In the meantime, feel free to commit to this branch if anyone would like to make changes, (or commit the changeset if this feels like it's in a good enough place). Cheers!