RSS Chat Routing

Chooses which posts go to rss.chat — by default post format, by default Post Kind, or per post — and brings replies home as real, verified Webmentions.

Why

RSS Chat syndicates a post when it carries the core chat post format:

if ( 'chat' !== \get_post_format( $post ) ) {
    return;
}

The handbook defines that format as "A chat transcript", which describes what a post contains. Sending a post to rss.chat is about where it goes. Using one for the other means a note has to claim it's a transcript to be syndicated, and Post Formats for Block Themes will badge it as one.

Upstream has been asked whether the check could be filterable: pfefferle/wordpress-rss-chat#6.

What it does

Settings → RSS Chat Routing, plus an rss.chat panel in the post sidebar.

Routing. Pick up to one default post format and up to one default post kind; either can be empty. A post matching either one is sent by default. Every post keeps a three-state override in the editor — Use the site default, Include in RSS Chat, Exclude from RSS Chat — and an explicit choice always wins. The panel shows the effective result and why ("Included because the post format is Status."). A fresh install defaults to the chat format, which is exactly what RSS Chat does alone, so activating changes nothing.

The decision, in precedence order:

1. Content rss.chat must never syndicate (drafts, other post types, password-protected posts, revisions, autosaves) is never sent, whatever else says.
2. A per-post exclude wins.
3. A per-post include wins.
4. Otherwise the post is sent when it matches the default format or the default kind.
5. Otherwise it stays home.

Micropub clients (Outpost among them) can send the override as mp-rss-chat-routing: inherit | include | exclude; omitted means inherit and the server-side decision stays authoritative. The same three states ride the REST API (meta._rss_chat_routing), where invalid values are rejected with a 400 rather than coerced.

Replies. Settings → Replies from rss.chat picks one of three modes:

• Imported comments (legacy) — RSS Chat's own importer, unchanged. The default; existing installs keep their behavior until you choose otherwise.
• Verified Webmentions — replies arrive as real Webmentions sent by the rss.chat server and verified by the Webmention plugin, which owns moderation, display, and updates. The legacy importer is switched off, and a Webmention whose source matches a reply the legacy importer already stored is rejected, so one remote reply can never become two comments. Needs an rss.chat server that sends Webmentions (see the companion server patch); the settings screen says so plainly until one exists.
• No reply import — replies stay on rss.chat.

Isolation. Comments that arrived from another network — Webmentions, ActivityPub replies, ATmosphere/Bluesky reactions, pingbacks — are never pushed back out to rss.chat, and rss.chat replies imported as comments are never federated onward (ActivityPub and ATmosphere already refuse foreign comments on their own; this plugin closes the rss.chat direction).

Permalinks. Every pushed item carries the post's canonical WordPress permalink in the rss.chat item's link field, which is what lets the server point a reply's Webmention back at the right post.

Migrating from 0.1.x

Nothing to do. The old format / all / none option shape is read in place: format becomes the chat default format, none becomes no defaults, and the first ticked kind becomes the default kind. An install still on all keeps sending everything until the settings screen is saved once — the screen says so. Stored per-post choices (1/0) keep their meaning forever. Settings changes only affect future publishes; nothing is bulk-syndicated, and excluding an already-synced post neither deletes nor re-sends the remote item.

How it works

Where the parent plugin exposes filters (rss_chat_should_syndicate, rss_chat_post_item, rss_chat_should_push_comment, rss_chat_backfeed_enabled), this plugin answers them directly. Until those land upstream, stand-ins produce the same result against the stock parent:

• Router sits either side of the actions RSS Chat syndicates on and answers get_post_format() for that one post, for the length of that one call, via the get_the_terms filter. Nothing is stored and nothing is cached wrongly.
• Link_Shim re-issues the parent's own /newpost request with the permalink added, only for requests to the configured server, only while a post push is in flight.
• Comment_Gate answers the parent's "already synced?" question with a sentinel for foreign comments, so inbound interactions are never re-broadcast.
• Micropub re-evaluates at after_micropub priority 40 — after Outpost's bridges (20) and Post Kinds (30) have set format and kind, which the parent's own hooks fire too early to see — and asks the parent to push. The parent's already-synced guard keeps it idempotent.

The test suite runs green against both the stock and the patched parent.

Tests

The PHPUnit suite loads the real RSS Chat plugin and asserts on whether it actually pushed:

composer install
WP_TESTS_DIR=~/.wp-tests/wordpress-tests-lib \
RSS_CHAT_DIR=/path/to/wordpress-rss-chat \
vendor/bin/phpunit

The editor panel has a headless harness that drives the real script through a stubbed wp global:

node tests/js/panel-harness.js assets/js/editor.js

tests/e2e-env/ holds two wp-env harnesses: run-webmention-e2e.sh proves the full round trip (status post → rss.chat item with permalink → reply → verified Webmention comment, idempotent, no echo, no legacy duplicate) against a local patched rss.chat server, and combo/run-combo-e2e.sh runs the routing decision with RSS Chat, Webmention, ActivityPub, IndieWeb, ATmosphere, IndieAuth, Micropub, Post Formats for Block Themes, and Post Kinds for IndieWeb all active at once.

Requires

WordPress 6.6, PHP 7.4, and the RSS Chat plugin. Post Kinds for IndieWeb is optional; without it the kind default is hidden and a stored kind default fails safe. The Webmention plugin is required only for the Verified Webmentions reply mode.