Interactivity API: Iteration for WP 6.6

[DAreRodz]

• Part of Block API #41236.

---

We completed everything for the first public release of the Interactivity API in WordPress 6.5. Now, during the next iteration―which is going to be shorter―, we aim to focus on improving the current API without releasing new features. This includes enhancing the developer experience (especially during debugging), better test coverage and code quality, as well as fixing any reported bugs.

Note that the list is expected to be modified. I've also added optional tasks we can work on if we find the time.

28-05 Update: All tasks have been redistributed for 6.6 release summary.

Punted to future releases

• Interactivity Router: Support Handling navigate() Failure States #59856
• Interactivity API: Allow async directive registration #60670
• Interactivity API: Defer hydration until node is scrolled near the viewport #58284

Won't do

• Interactivity API: Debug - Show directive names included in each Directives component on Preact’s debug tools #60049
• Interactivity API: Added comments for directive parsing #61456

Ready for 6.6

Enhancements

• Interactivity API: Include preact/debug when SCRIPT_DEBUG is enabled #60514
• Introduce wp-on-async directive as performant alternative over synchronous wp-on directive #61885
• Update the query block to permit non-core interactive blocks #60006
• Add Interactivity API hooks to wp_admin wordpress-develop#6453
• KSES: Allow leading trailing double hyphen in data attributes wordpress-develop#6598
• Interactivity API: Add debug notices for SSR wordpress-develop#6413
• Interactivity API: Add server derived state getter handling wordpress-develop#6394

Bug fixes

• Interactivity: Return useMemo and useCallback hooks #60474
• Interactivity API: Allow multiple event handlers for the same type with data-wp-on. #60661
• Interactivity API: Allow multiple event handlers for the same type with data-wp-on-document and data-wp-on-window. #61009
• Interactivity API: Prevent wrong written directives from killing the runtime #61249
• Interactivity API: Prevent empty namespace or different namespaces from killing the runtime #61409
• Interactivity API bug: Fix fatal error when trying to use a stdClass as state-context. wordpress-develop#6672
• Interactivity API: Increase directive wp-each-child priority. #62293

Code Quality

• Interactivity API: Turn named capturing groups back into numbered ones inside toVdom #61728
• Interactivity API: Move all utils inside utils.ts #61721
• Interactivity API refactor to TypeScript (utils & kebabToCamelCase) #60149
• Interactivity: Strict type checking #59865
• Interactivity API: Add types for warn helper. #61687
• Interactivity API : Refactor interactivity-router to TS #61730
• Editor: Move Interactivity directives processing to WP_Block class wordpress-develop#6331

[felixarntz]

@DAreRodz @gziolo What's the best path to consider additional workstreams for the Interactivity API for 6.6?

Context is that @westonruter and myself have been exploring ideas to facilitate better INP performance centrally via the Interactivity API. For instance, we could automatically yield certain actions and callbacks to the main thread to reduce contention between multiple event listeners. We're close to formalizing our proposal in an issue, and it would be great to eventually include this effort here, if the team is on board.

One of the changes we're proposing may require a BC break in the API which we could handle with a deprecation strategy, but it would also benefit from being implemented sooner than later, now that the API is still very new and not yet as widely adopted outside of core.

[DAreRodz]

Hey @felixarntz, thanks for raising this up! 😊

I'm unsure what would be the "best path" (maybe @gziolo could help), but as this tracking issue is meant to be flexible, I would be happy to include your work. Let's wait for the proposal to see if we can have it ready for WP 6.6 and how the mentioned breaking changes could impact the current API.

[gziolo]

That sounds excellent, @felixarntz. I'm looking forward to seeing the proposal.

@DAreRodz, the Iteration issues mostly bring focus and increase the visibility of what to expect in WordPress 6.6, but it doesn't mean we can't change it. In practice, we should always be open to changing the plans based on the feedback and discoveries from the community experts 😍

[sirreal]

The ability to use existing WordPress Scripts from Script Modules is one of the most impactful things we can work on for the Interactivity API. Anything built with the Interactivity API must be a script module, so although it's not strictly Interactivity API, resolving this ticket for script and module interoperability seems very important: https://core.trac.wordpress.org/ticket/60647

[sethrubenstein]

Second @sirreal calls for WordPress scripts. We use wp-api-fetch and wp-url with interactive blocks, a lot. Making that easier from a dev tooling perspective to automatically enqueue those scripts would be greatly appreciated.

[ermincelikovic]

Is there any chance to get interactivity api outside of blocks? For example in custom php templates?

[felixarntz]

@ermincelikovic While I believe it's not documented, it should already be possible. The main caveat is that by default custom PHP templates wouldn't be processed server-side, so you have to make sure the attributes that are dynamic via the Interactivity API are initialized with their correct value.

As a proof of concept, I have been working on WordPress/wordpress-develop#5795 where I am using the Interactivity API for all dynamic functionality of the Twenty Twenty-One theme. Maybe that's helpful.

[luisherranz]

default custom PHP templates wouldn't be processed server-side, so you have to make sure the attributes that are dynamic via the Interactivity API are initialized with their correct value

You can process them using wp_interactivity_process_directives 🙂

[ermincelikovic]

default custom PHP templates wouldn't be processed server-side, so you have to make sure the attributes that are dynamic via the Interactivity API are initialized with their correct value

You can process them using wp_interactivity_process_directives 🙂

This looks great!
How would I import { store, getContext } from "@wordpress/interactivity"; within a context of php template or a traditional script.js file in the theme though?

EDIT:
Just found out that script modules are also introduced in 6.5:
https://make.wordpress.org/core/2024/03/04/script-modules-in-6-5/

[cbravobernal]

I've added the suggestions in Typescripting utils PR. Ready to be reviewed again.
#60149

[sirreal]

How would I import { store, getContext } from "@wordpress/interactivity"; within a context of php template or a traditional script.js file in the theme though?

@ermincelikovic The @wordpress/interactivity script module is only available to other script modules at this time. Using it from WordPress scripts is not supported at this time. See this ticket for details.

[DAreRodz]

I've added two PRs to the description above.

• Interactivity API: Allow multiple event handlers for the same type with data-wp-on. #60661
• Interactivity API: Allow async directive registration #60670

The first one could be considered a bug fix (I've added it under that category), and so be released in a minor WP release.

[DAreRodz]

The fix for data-wp-on is merged.

• Interactivity API: Allow multiple event handlers for the same type with data-wp-on. #60661

I've also opened an issue to fix the same problem in data-wp-on-window and data-wp-on-document.

• Support multiple data-wp-on-window or data-wp-on-document directive with the same event #60683

[fabiankaegy]

In addition to #60035 I'd love to see some more useful debugging for the following areas:

• output a warning when you use directives in the markup of a block that doesn't have the interactivity support enabled

• add better client side errors when you try to access a property on a store that doesn't exist

• add a guide for how to connect the preact dev tools to the interactivity API

---

Besides debugging here are some other things that I would love to see in the 6.6 cycle.

• some documentation for working with external stores / making a store extensible

• refine clarity in documentation of what the difference between callbacks and actions are

• add documentation for client side routing like the query block does it

[sirreal]

I've added WordPress/wordpress-develop#6394 for server-side derived state. It's ready for review.

[sirreal]

I've just added 3 items related to data-wp-ignore directive.

• It needs to be documented, it's not in the API Reference right now.
• Interactivity: Ensure ignore directives are stable #60744
• Interactivity API: Ignore ignore directives on the server wordpress-develop#6405

I think there's a bug with the server processing of ignore directives I'm attempting to fix in WordPress/wordpress-develop#6405. I think that nodes with that attribute and their descendants should be ignored completely, no processing should happen on or under a node with data-wp-ignore. @cbravobernal or @DAreRodz can you confirm?

Right now ignore directives are not handled on the server, so those nodes and their descendants are processed. I discovered that while working on tests for #60744.

[sirreal]

I've created this ticket to handle property access on PHP objects in interactivity state, only arrays are well handled at the moment: https://core.trac.wordpress.org/ticket/61039

[cbravobernal]

I've created a PR to add a couple of warnings if Server Directives processing fails.

• Interactivity API: Add debug notices for SSR wordpress-develop#6413

[cbravobernal]

Created a PR to handle multiple document and window events in the same element.

• Interactivity API: Allow multiple event handlers for the same type with data-wp-on-document and data-wp-on-window. #61009

[cbravobernal]

Created a PR to avoid a wrong directive from killing the runtime.

• Interactivity API: Prevent wrong written directives from killing the runtime #61249

[cbravobernal]

Added another PR, avoiding an emtpy or a wrong namespace from killing the runtime too.

• Interactivity API: Prevent empty namespace or different namespaces from killing the runtime #61409

[cbravobernal]

Added a follow-up issue to improve the readability of the directive processing function inside vdom.ts as @sirreal requested in #61249 (comment)

• Interactivity API: Improve readability in directives check function inside vdom.ts #61455

[westonruter]

Added another performance issue which came out of the discussion in #60574 (comment):

• Event directives can only be synchronous without the option for them to be asynchronous/passive #61634

[cbravobernal]

Added a minimum PR with two types:

• Interactivity API: Add types for warn helper. #61687

[michalczaplinski]

Based on discussion in #60979 (comment) I've opened a PR to add build configuration for a standalone package:

• Interactivity API: Add build configuration for a standalone package  #61681

[michalczaplinski]

I've started a PR to migrate @wordpress/interactivity-router to TS:

• Interactivity API : Refactor interactivity-router to TS #61730

[fabiankaegy]

Hi all 👋

Reminder: The release candidate for Gutenberg Version 18.5 is scheduled for next Friday (May 31st). So anything that is supposed to make it into WordPress 6.6 must be merged by then.

Please raise any important issues that need additional attention :)

[cbravobernal]

Hi 👋

I updated the description of the main tracking issue with the list of PRs that won't be included in this release, the PRs that still needs review or commit and the PRs ready for 6.6.

[sirreal]

I've added WordPress/wordpress-develop#6453 as an enhancement for 6.6 (let Interactivity API be used in WP Admin).

[cbravobernal]

I've added a unit test to the bug fix for the fatal error if a state or context uses a stdClass. Ready to review: 👀
WordPress/wordpress-develop#6672

[cbravobernal]

Added a merged a bug fix for data-wp-each-child priority.

• Interactivity API: Increase directive wp-each-child priority. #62293

[luisherranz]

Closing as finished.

The work for WordPress 6.7 will be tracked in the following tracking issue:

• Interactivity API iteration for WordPress 6.7 #63232

[otakupahp]

The new version introduced a BIG error... Now instead of returning an object, get_context() returns a string

[sirreal]

The new version introduced a BIG error... Now instead of returning an object, get_context() returns a string

@otakupahp Will you please open a new issue with details about the problem?

[otakupahp]

Will you please open a new issue with details about the problem?

I would love, but I spend that time tracking the error, and I'm terrible creating those issues. But I found the reason for it.

Before 6.6 I had an array with other arrays:

array(
    array( 'id' => 1, 'item' => 'item 1 name' ),
    array( 'id' => 1, 'item' => 'item 2 name' ),
    array( 'id' => 1, 'item' => 'item 3 name' ),
);

That create this JSON:

[
    {"id":1, "item":"item 1 name"},
    {"id":2, "item":"item 2 name"},
    {"id":3, "item":"item 3 name"},
]

The Interactive API created a context object that contains the array without problems.

Now, it just renders a string instead of an array object

To fix the error, I have to modify my array into this:

array(
    'data' => array(
        array( 'id' => 1, 'item' => 'item 1 name' ),
        array( 'id' => 1, 'item' => 'item 2 name' ),
        array( 'id' => 1, 'item' => 'item 3 name' ),
    )
);

Which created this JSON:

{
    "data": [
        {"id":1, "item":"item 1 name"},
        {"id":2, "item":"item 2 name"},
        {"id":3, "item":"item 3 name"},
    ]
}

This is indeed parsed as an object.

SO, I must patch my code to make it work...

Maybe this was introduced on #6672

[luisherranz]

I have created an issue to investigate this bug:

• Interactivity API: Inability to use plain arrays in context #63651

@otakupahp, could you please comment on that issue to provide a detailed list of the steps we need to take to reproduce the problem? Thank you.