WP REST API: Version 2.0 Beta 9

For the last REST APIREST API The REST API is an acronym for the RESTful Application Program Interface (API) that uses HTTP requests to GET, PUT, POST and DELETE data. It is how the front end of an application (think “phone app” or “website”) can communicate with the data store (think “database” or “file system”) https://developer.wordpress.org/rest-api/. release of 2015, we bring you: 2.0 BetaBeta A pre-release of software that is given out to a large group of users to trial under real conditions. Beta versions have gone through alpha testing in-house and are generally fairly close in look, feel and function to the final product; however, design changes often occur as part of the process. 9 “You Don’t Win Friends With Salad”. Download it from the plugin repository or from GitHub.

Should I use 2.0 Beta 9 in production?

This is a great question. I (Daniel) will do my best to answer from my perspective — Ryan, Rachel or Joe may have different opinions.

As many of you may already know, the v1.x branchbranch A directory in Subversion. WordPress uses branches to store the latest development code for each major release (3.9, 4.0, etc.). Branches are then updated with code for any minor releases of that branch. Sometimes, a major version of WordPress and its minor versions are collectively referred to as a "branch", such as "the 4.0 branch". is essentially deprecated and only maintained for security and major compatibility issues. Even its latest release, v1.2.4, still includes some annoying bugs. The v2.0 Betas introduce aton of new features, functionality, and general improvements. But, there will never be a formal v2.0 pluginPlugin A plugin is a piece of software containing a group of functions that can be added to a WordPress website. They can extend functionality or add new features to your WordPress websites. WordPress plugins are written in the PHP programming language and integrate seamlessly with WordPress. These can be free in the WordPress.org Plugin Directory https://wordpress.org/plugins/ or can be cost-based plugin from a third-party release — v2.0 will be endpoint inclusion into WordPress coreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress..

Right now, we’re doing our darned best to get the endpoints into core at the end of January 2016. Between now and then we have at least 74 issues to wade through. Beta 9 includes 32 merged pull requests.

In the interest of feeling confident about the code we’re committing to core, we are and will be making breaking changes in the Betas. Significantly, Beta 10 will remove the core directory, and will be incompatible with WordPress 4.3.

Short answer: you’re welcome to use the Betas in production if you understand the ramifications. When updating, we expect you to read through the changelog and thoroughly test each release with your project. You should probably have test coverage on any custom endpoints you’re writing. And, set aside time to properly debug any issues you uncover and submit pull requests with test coverage.

If you aren’t comfortable with aforementioned ramifications, please refrain from using the v2.0 Betas in production. We do encourage everyone to use them locally, or in staging / test environments, and look forward to your feedback.


Here are some highlights:

  • Move tags and categories to top-level endpoints. Tags are now accessible at `/wp/v2/tags`, and categories accessible at `/wp/v2/categories`. Post terms reside at `/wp/v2/posts//tags` and `/wp/v2//categories`.
  • Return object for requests to `/wp/v2/taxonomies`. This is consistent with `/wp/v2/types` and `/wp/v2/statuses`.
  • Remove `rest_get_timezone()`. `json_get_timezone()` was only ever used in v1. This function causes fatals, and shouldn’t be used.
  • Rename `register_api_field()` to `register_rest_field()`. Introduces a `register_api_field()` function for backwards compat, which calls `_doing_it_wrong()`. However, `register_api_field()` won’t ever be committed to WordPress core, so you should update your function calls.
  • Change taxonomies’ `post_type` argument to `type`. It’s consistent with how we’re exposing post types in the APIAPI An API or Application Programming Interface is a software intermediary that allows programs to interact with each other and share data in limited, clearly defined ways..
  • Sync infrastructure with shipped in WordPress 4.4.
    • `wp-includes/rest-api/rest-functions.php` is removed, and its functions moved into `wp-includes/rest-api.php`.
    • Send nocache headers for REST requests.
    • Fix handling of HEAD requests.
    • Mark `WP_REST_Server::get_raw_data()` as static.
    • Unabbreviate error string.
  • Change terms endpoints to use `term_id` not `tt_id`.
  • Standardize declaration of `context` param for `GET` requests across controllers. However, we’re still inconsistent in which controllers expose which params. Follow #1845 for further discussion.
  • Link types / taxonomies to their collections, and vice versa. Collections link to their type / taxonomyTaxonomy A taxonomy is a way to group things together. In WordPress, some common taxonomies are category, link, tag, or post format. https://codex.wordpress.org/Taxonomies#Default_Taxonomies. with the `about` relation; types / taxonomies link to their collection with the `item` relation, which is imperfect and may change in the future.

As always, we have a detailed changelog as well as the full set of changes if you’re interested.

#feature-plugins, #json-api, #rest-api