Merge Proposal Discussion: REST API Content Endpoints

There are discussion meetings and office hours in #core-restapi at 2016-10-14 14:00UTC and 2016-10-14 19:00UTC on Friday the 14th. Our next team meeting is on 2016-10-17 14:00UTC. Please attend some of all of these, because

We are meeting at 2016-10-18 01:00 UTC to make a decision on this merge proposal!

To that end, the below discussion points will be updated regularly, please leave comments on this post or join the conversation in #core-restapi.

Yesterday at the dev chat 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. Team proposed the Content API Endpoints for merge in WordPress 4.7. There was popular support for this feature but as @jorbin and @helen noted that the lack of dissent suggested additional review is needed, so the API Team is continuing to seek thorough review & constructive criticism of the content endpoints, including the open questions previously shared on the week 7 and week 8 API team updates.

The merge proposal also engendered follow-up discussion in the #core-restapi channel about the benefit content endpoints bring to coreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress., whether having such endpoints built in is quantifiably more beneficial than having them as a 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, whether moving development from a plugin to core would slow development, and whether the endpoints as-proposed have been sufficiently reviewed for security and performance. We attempt to capture those questions & concerns (and the perspectives on them) below.

Security

Have the content API endpoints been thoroughly reviewed for security?

  • The 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/. plugin has been on HackerOne for over a year with paid bounties for bugs
  • @barry has begun a security review

Performance

How does the API measure up against alternatives? Are there concerns about how the API could impact the servers to which it is deployedDeploy Launching code from a local development environment to the production web server, so that it's available to visitors.?

  • DeliciousBrains did a performance comparison with Admin AJAX and found the REST API to have a performance improvement (These tests have not yet been independently verified)
  • @mikeschroder notes in the comments that using the REST API in place of Adminadmin (and super admin)-Ajax will also bring speed benefits by permitting many previously-uncacheable requests to be cached.

User Feedback

Are the content endpoints sufficiently well-tested & vetted by the community?

  • @matt questions whether feedback is coming too late in development for concerns to be acted upon
    • @rmccue notes that the v2 endpoints were created based on user feedback; REST API endpoints are being deployed by plugins and running on VIP, and the content endpoints have been in wide use across a variety of sites, leading to 90+ code contributors and far more developers’ support & feedback on the endpoints
  • @rmccue has also reached out to Phil Sturgeon for feedback and will follow up

Do Content Endpoints Benefit Core Development?

Will having these endpoints in core improve future core development, or solve any immediate problems?

  • @bradyvercher suggested that the content API endpoints would remove the need to write a variety of one-off ajax callbacks when developing future WordPress Core AJAX functionality
  • @westonruter notes that the customizerCustomizer Tool built into WordPress core that hooks into most modern themes. You can use it to preview and modify many of your site’s appearance settings. could dynamically create settings for posts and other kinds of content without having to wire up new admin-ajax handlers

Will Merging Negatively Impact API Development?

Will having to work through tracTrac An open source project by Edgewall Software that serves as a bug tracker and project management tool for WordPress. instead of GitHubGitHub GitHub is a website that offers online implementation of git repositories that can can easily be shared, copied and modified by other developers. Public repositories are free to host, private repositories require a paid subscription. GitHub introduced the concept of the ‘pull request’ where code changes done in branches by contributors can be reviewed and discussed before being merged be the repository owner. https://github.com/ cause development to atrophy?

  • @jjj argues that merging will slow development, because GitHub-hosted plugins are not bound to WordPress release cycles and have less overhead for features to be developed and deployed for testing. @jjj requested a plan for how the REST API will be developed going forward after the merge of these endpoints that would account for the added friction.
  • @krogsgard countered that core increases the visibility of a project like the content endpoints
    • The number of new contributors in this SlackSlack Slack is a Collaborative Group Chat Platform https://slack.com/. The WordPress community has its own Slack Channel at https://make.wordpress.org/chat/. discussion suggests that this merge proposal is bringing in new voices; whether this supports Brian’s point or not, the team is grateful for the breadth of perspectives being shared -Ed.
  • @rachelbaker suggested that the API endpoints are sufficiently inter-dependent with core WordPress code that maintaining the plugin separately amounts to maintaining a fork, and that such separated development is untenable long-term.
  • @matt hopes that a merge of these endpoints would slow release speed, but not development speed; @rmccue feels that development speed will stay the same or increase, and that tying releases to WordPress Core increases the stability and predictability of the API endpoints.
  • The versioning of the API endpoints supports forward compatibility

Do Content Endpoints Belong on Every WordPress Site?

What are the pros and cons to having every WordPress site have content API endpoints?

  • @rmccue suggests the API has networknetwork (versus site, blog) effects that can only be realized with a large install base. @krogsgard draws a comparison to RSS, the widespread availability of which enables everything from podcasting from WP to the use of apps like Feedly.
  • @matt suggests that the Atom API is a better analogue than RSS, which is an independent and pre-existing standard, and that network effects could be tested through inclusion in Jetpack
  • @joostdevalk notes that many plugins, like Yoast, have data tied to existing content such as posts and pages; either they expose the content through their own endpoints, or core does. If Core exposes content types through the API then plugins may build on top of that shared foundation, not independently reinvent the wheel. “if this doesn’t end up in core, we’ll start rolling our own API for stuff. Others will too. Interoperability won’t be there, for even the most basic stuff. I think this isn’t like RSS, I think this is much more like all of us using the same table space in MySQLMySQL MySQL is a relational database management system. A database is a structured collection of data where content, configuration and other options are stored. https://www.mysql.com/..”
    • @shelob9 and @masonjames agree that merging the endpoints would create a consistent and reliable open “standard” that WordPress developers can use instead of continually reinventing how to read and edit post data over HTTPHTTP HTTP is an acronym for Hyper Text Transfer Protocol. HTTP is the underlying protocol used by the World Wide Web and this protocol defines how messages are formatted and transmitted, and what actions Web servers and browsers should take in response to various commands..
    • In response to the question “what prevents you from building on the endpoints in their plugin form,” @joostdevalk went on to note that plugin dependencies would make that a viable option, but that burden currently lies on the user. Plugin installation is not frictionless.
  • Can these endpoints be bundled? short takeaway: no
    • Woo bundled the API infrastructure before it was merged; doing so for content endpoints would require bundling prohibitively large amounts of endpoint code.
    • @nerrad worries that if plugins bundle different versions of the endpoints plugin, then those plugins may conflictconflict A conflict occurs when a patch changes code that was modified after the patch was created. These patches are considered stale, and will require a refresh of the changes before it can be applied, or the conflicts will need to be resolved. if all bundled copies are not kept in sync.
      • @nerrad clarifies in the comments below that these worries also encompass the additional risk of conflicts when plugin authors each build their own versions of these content endpoints, instead of leveraging a shared standard: if two plugins each expose their own REST collection for posts, a developer working on a site with multiple such endpoints will need to decide which to extend, and will then have their extension tied to that specific plugin rather than to a core API.
  • @schrapel and @jorbin discussed that these content endpoints make it much easier to crawl a site, which also brings some potential performance concerns: no new content is exposed, but the process of aggregating it is easier and more easily automated.
  • In the  comments below @foliovision believes that merging the endpoints will be the best way to assert the level of back-compatibility that mid-size agencies need in order to confidently utilize the endpoints.

Please leave thoughts, questions, concerns, comments & experience in the comments below. Thank you!

Edited 2016-10-16 to include the below comments into the body of the post

#4-7, #rest-api