| 1 |
<?php |
| 2 |
/** |
| 3 |
* Router class. |
| 4 |
* |
| 5 |
* @package Activitypub |
| 6 |
*/ |
| 7 |
|
| 8 |
namespace Activitypub; |
| 9 |
|
| 10 |
use Activitypub\Collection\Actors; |
| 11 |
use Activitypub\Collection\Outbox; |
| 12 |
|
| 13 |
/** |
| 14 |
* Router class. |
| 15 |
*/ |
| 16 |
class Router { |
| 17 |
/** |
| 18 |
* Initialize the class, registering WordPress hooks. |
| 19 |
*/ |
| 20 |
public static function init() { |
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\add_action( 'init', array( self::class, 'add_rewrite_rules' ), 11 ); |
| 22 |
|
| 23 |
\add_action( 'send_headers', array( self::class, 'add_headers' ) ); |
| 24 |
\add_filter( 'template_include', array( self::class, 'render_activitypub_template' ), 99 ); |
| 25 |
\add_action( 'template_redirect', array( self::class, 'template_redirect' ) ); |
| 26 |
\add_filter( 'redirect_canonical', array( self::class, 'redirect_canonical' ), 10, 2 ); |
| 27 |
\add_filter( 'redirect_canonical', array( self::class, 'no_trailing_redirect' ), 10, 2 ); |
| 28 |
\add_filter( 'query_vars', array( self::class, 'add_query_vars' ) ); |
| 29 |
|
| 30 |
\add_action( 'parse_query', array( self::class, 'fix_is_home_check' ) ); |
| 31 |
} |
| 32 |
|
| 33 |
/** |
| 34 |
* Add rewrite rules. |
| 35 |
*/ |
| 36 |
public static function add_rewrite_rules() { |
| 37 |
/* |
| 38 |
* If another system needs to take precedence over the ActivityPub rewrite rules, |
| 39 |
* they can define their own and will manually call the appropriate functions as required. |
| 40 |
*/ |
| 41 |
if ( ACTIVITYPUB_DISABLE_REWRITES ) { |
| 42 |
return; |
| 43 |
} |
| 44 |
|
| 45 |
\add_rewrite_rule( |
| 46 |
'^authorize_interaction/?$', |
| 47 |
'index.php?rest_route=/' . ACTIVITYPUB_REST_NAMESPACE . '/interactions', |
| 48 |
'top' |
| 49 |
); |
| 50 |
|
| 51 |
if ( ! \class_exists( 'Webfinger' ) ) { |
| 52 |
\add_rewrite_rule( |
| 53 |
'^.well-known/webfinger', |
| 54 |
'index.php?rest_route=/' . ACTIVITYPUB_REST_NAMESPACE . '/webfinger', |
| 55 |
'top' |
| 56 |
); |
| 57 |
} |
| 58 |
|
| 59 |
if ( ! \class_exists( 'Nodeinfo_Endpoint' ) && true === (bool) \get_option( 'blog_public', 1 ) ) { |
| 60 |
\add_rewrite_rule( |
| 61 |
'^.well-known/nodeinfo', |
| 62 |
'index.php?rest_route=/' . ACTIVITYPUB_REST_NAMESPACE . '/nodeinfo', |
| 63 |
'top' |
| 64 |
); |
| 65 |
} |
| 66 |
|
| 67 |
// Authorization Server Metadata (RFC 8414). |
| 68 |
\add_rewrite_rule( |
| 69 |
'^.well-known/oauth-authorization-server', |
| 70 |
'index.php?rest_route=/' . ACTIVITYPUB_REST_NAMESPACE . '/oauth/authorization-server-metadata', |
| 71 |
'top' |
| 72 |
); |
| 73 |
|
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// Must precede the generic @username rule, which would otherwise match "application" as an actor username. |
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\add_rewrite_rule( '^@application\/?$', 'index.php?rest_route=/' . ACTIVITYPUB_REST_NAMESPACE . '/application', 'top' ); |
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\add_rewrite_rule( '^@([\w\-\.]+)\/?$', 'index.php?actor=$matches[1]', 'top' ); |
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\add_rewrite_endpoint( 'activitypub', EP_AUTHORS | EP_PERMALINK | EP_PAGES ); |
| 78 |
} |
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|
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/** |
| 81 |
* Return a AS2 JSON version of an author, post or page. |
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* |
| 83 |
* @param string $template The path to the template object. |
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* |
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* @return string The new path to the JSON template. |
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*/ |
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public static function render_activitypub_template( $template ) { |
| 88 |
if ( \wp_is_serving_rest_request() || \wp_doing_ajax() ) { |
| 89 |
return $template; |
| 90 |
} |
| 91 |
|
| 92 |
if ( ! is_activitypub_request() || ! should_negotiate_content() ) { |
| 93 |
$is_outbox_item = \get_query_var( 'p' ) && Outbox::POST_TYPE === \get_post_type( \get_query_var( 'p' ) ); |
| 94 |
$is_preflight = isset( $_SERVER['REQUEST_METHOD'] ) && 'OPTIONS' === $_SERVER['REQUEST_METHOD']; |
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|
| 96 |
if ( $is_outbox_item && $is_preflight ) { |
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/* |
| 98 |
* CORS preflight: override WordPress 404 so the browser |
| 99 |
* accepts the preflight response (must be 2xx). |
| 100 |
*/ |
| 101 |
\status_header( 200 ); |
| 102 |
} elseif ( $is_outbox_item ) { |
| 103 |
// Return 406 for non-ActivityPub requests to outbox items since they only support ActivityPub requests. |
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\set_query_var( 'is_404', true ); |
| 105 |
\status_header( 406 ); |
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} |
| 107 |
|
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return $template; |
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} |
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|
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$activitypub_object = Query::get_instance()->get_activitypub_object(); |
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$queried_object = Query::get_instance()->get_queried_object(); |
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|
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/* |
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* Serve the Tombstone for a deleted object — but not while an authorized |
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* user is previewing it. During an editor `?preview=true` request, |
| 117 |
* `is_post_publicly_queryable()` treats a draft or pending post as |
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* queryable only for a user who can edit it, so the author can still use |
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* the Fediverse Preview on a post they just soft-deleted (which is |
| 120 |
* otherwise already in the tombstone registry). |
| 121 |
* |
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* The bypass is scoped to that preview request on purpose. A normal |
| 123 |
* ActivityPub fetch (no `preview`) of a tombstoned URL always gets the |
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* Tombstone — even if the URL now resolves to a fresh public post because |
| 125 |
* its slug was reused — since remote servers were told that id is gone. |
| 126 |
* The legitimate restore path clears the registry entry itself, via |
| 127 |
* `Create::maybe_unbury()` when the re-publish Create is queued. |
| 128 |
*/ |
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$is_authorized_preview = \get_query_var( 'preview' ) |
| 130 |
&& $queried_object instanceof \WP_Post |
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&& is_post_publicly_queryable( $queried_object ); |
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|
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if ( |
| 134 |
Tombstone::exists_local( Query::get_instance()->get_request_url() ) |
| 135 |
&& ! $is_authorized_preview |
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) { |
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// Set 410 Gone for permanently deleted posts, 200 OK for soft-deleted. |
| 138 |
if ( ! $activitypub_object ) { |
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\status_header( 410 ); |
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} |
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|
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return ACTIVITYPUB_PLUGIN_DIR . 'templates/tombstone-json.php'; |
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} |
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|
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/* |
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* Refuse to expose the content-negotiated representation of a post |
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* that is no longer publicly queryable (non-public status, AP |
| 148 |
* visibility flipped, post-type support removed, etc.). The |
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* lifecycle gate in `is_post_disabled()` intentionally lets such |
| 150 |
* posts through the federation pipeline so a Delete can fire, but |
| 151 |
* that escape hatch must not leak into front-end rendering during |
| 152 |
* the window between status change and Delete delivery. |
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*/ |
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if ( |
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$activitypub_object && |
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$queried_object instanceof \WP_Post && |
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'ap_outbox' !== $queried_object->post_type && |
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! is_post_publicly_queryable( $queried_object ) |
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) { |
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return $template; |
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} |
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|
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$activitypub_template = false; |
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|
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if ( $activitypub_object ) { |
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if ( \get_query_var( 'preview' ) ) { |
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\defined( 'ACTIVITYPUB_PREVIEW' ) || \define( 'ACTIVITYPUB_PREVIEW', true ); |
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|
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/** |
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* Filter the template used for the ActivityPub preview. |
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* |
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* @param string $activitypub_template Absolute path to the template file. |
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*/ |
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$activitypub_template = \apply_filters( 'activitypub_preview_template', ACTIVITYPUB_PLUGIN_DIR . '/templates/post-preview.php' ); |
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} else { |
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$activitypub_template = ACTIVITYPUB_PLUGIN_DIR . 'templates/activitypub-json.php'; |
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} |
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} |
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|
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/* |
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* Check if the request is authorized. |
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* |
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* @see https://www.w3.org/wiki/SocialCG/ActivityPub/Primer/Authentication_Authorization#Authorized_fetch |
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* @see https://swicg.github.io/activitypub-http-signature/#authorized-fetch |
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*/ |
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if ( $activitypub_template && use_authorized_fetch() ) { |
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$verification = Signature::verify_http_signature( $_SERVER ); |
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if ( \is_wp_error( $verification ) ) { |
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\status_header( 401 ); |
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|
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// Fallback as template_loader can't return http headers. |
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return $template; |
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} |
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} |
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|
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if ( $activitypub_template ) { |
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\set_query_var( 'is_404', false ); |
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|
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// Check if header already sent. |
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if ( ! \headers_sent() ) { |
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// Send 200 status header. |
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\status_header( 200 ); |
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} |
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|
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return $activitypub_template; |
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} |
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|
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return $template; |
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} |
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|
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/** |
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* Add the 'self' link to the header. |
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*/ |
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public static function add_headers() { |
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$id = Query::get_instance()->get_activitypub_object_id(); |
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|
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/* |
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* Send CORS headers for resolved ActivityPub objects and outbox |
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* items. Outbox items need CORS even when the object ID doesn't |
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* resolve, because browser preflight requests don't carry the |
| 221 |
* Authorization header needed to authenticate private items. |
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*/ |
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$post_id = \get_query_var( 'p' ); |
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$is_outbox_url = $post_id && Outbox::POST_TYPE === \get_post_type( $post_id ); |
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|
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if ( ! \headers_sent() && ( $id || $is_outbox_url ) ) { |
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\header( 'Access-Control-Allow-Origin: *' ); |
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\header( 'Access-Control-Allow-Methods: GET, OPTIONS' ); |
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\header( 'Access-Control-Allow-Headers: Accept, Authorization, Content-Type' ); |
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} |
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|
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if ( ! $id ) { |
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return; |
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} |
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|
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if ( ! \headers_sent() ) { |
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\header( 'Link: <' . \esc_url( $id ) . '>; title="ActivityPub (JSON)"; rel="alternate"; type="application/activity+json"', false ); |
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|
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if ( \get_option( 'activitypub_vary_header', '1' ) ) { |
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// Send Vary header for Accept header. |
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\header( 'Vary: Accept', false ); |
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} |
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} |
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|
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\add_action( |
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'wp_head', |
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static function () use ( $id ) { |
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echo PHP_EOL . '<link rel="alternate" title="ActivityPub (JSON)" type="application/activity+json" href="' . \esc_url( $id ) . '" />' . PHP_EOL; |
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} |
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); |
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} |
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|
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/** |
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* Remove trailing slash from ActivityPub @username requests. |
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* |
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* @param string $redirect_url The URL to redirect to. |
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* @param string $requested_url The requested URL. |
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* |
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* @return string $redirect_url The possibly-unslashed redirect URL. |
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*/ |
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public static function no_trailing_redirect( $redirect_url, $requested_url ) { |
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if ( \get_query_var( 'actor' ) ) { |
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return $requested_url; |
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} |
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|
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return $redirect_url; |
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} |
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|
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/** |
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* Add support for `p` and `author` query vars. |
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* |
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* @param string $redirect_url The URL to redirect to. |
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* @param string $requested_url The requested URL. |
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* |
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* @return string $redirect_url |
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*/ |
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public static function redirect_canonical( $redirect_url, $requested_url ) { |
| 278 |
if ( ! is_activitypub_request() ) { |
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return $redirect_url; |
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} |
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|
| 282 |
$query = \wp_parse_url( $requested_url, PHP_URL_QUERY ); |
| 283 |
|
| 284 |
if ( ! $query ) { |
| 285 |
return $redirect_url; |
| 286 |
} |
| 287 |
|
| 288 |
$query_params = \wp_parse_args( $query ); |
| 289 |
unset( $query_params['activitypub'] ); |
| 290 |
unset( $query_params['stamp'] ); |
| 291 |
|
| 292 |
if ( 1 !== \count( $query_params ) ) { |
| 293 |
return $redirect_url; |
| 294 |
} |
| 295 |
|
| 296 |
if ( isset( $query_params['p'] ) ) { |
| 297 |
return null; |
| 298 |
} |
| 299 |
|
| 300 |
if ( isset( $query_params['author'] ) ) { |
| 301 |
return null; |
| 302 |
} |
| 303 |
|
| 304 |
return $requested_url; |
| 305 |
} |
| 306 |
|
| 307 |
/** |
| 308 |
* Custom redirects for ActivityPub requests. |
| 309 |
* |
| 310 |
* @return void |
| 311 |
*/ |
| 312 |
public static function template_redirect() { |
| 313 |
global $wp_query; |
| 314 |
|
| 315 |
$comment_id = \get_query_var( 'c', null ); |
| 316 |
|
| 317 |
// Check if it seems to be a comment. |
| 318 |
if ( $comment_id ) { |
| 319 |
$comment = \get_comment( $comment_id ); |
| 320 |
|
| 321 |
// Load a 404-page if `c` is set but not valid. |
| 322 |
if ( ! $comment ) { |
| 323 |
$wp_query->set_404(); |
| 324 |
return; |
| 325 |
} |
| 326 |
|
| 327 |
// Stop if it's not an ActivityPub comment. |
| 328 |
if ( is_activitypub_request() && ! is_local_comment( $comment ) ) { |
| 329 |
return; |
| 330 |
} |
| 331 |
|
| 332 |
\wp_safe_redirect( \get_comment_link( $comment ) ); |
| 333 |
exit; |
| 334 |
} |
| 335 |
|
| 336 |
/* |
| 337 |
* Skip the actor branch when this looks like an actor-scoped FEP-7aa9 |
| 338 |
* stamp URL: numeric `actor` paired with a `stamp`. Those resolve to a |
| 339 |
* FeatureAuthorization via Activitypub\Query, not via the username |
| 340 |
* lookup which would 404 the numeric ID. Non-numeric actors fall |
| 341 |
* through to the regular Mastodon-style profile lookup. |
| 342 |
*/ |
| 343 |
$actor = \get_query_var( 'actor', null ); |
| 344 |
$is_stamp_url = $actor && \get_query_var( 'stamp' ) && \ctype_digit( (string) $actor ); |
| 345 |
if ( $actor && ! $is_stamp_url ) { |
| 346 |
$actor = Actors::get_by_username( $actor ); |
| 347 |
if ( ! $actor || \is_wp_error( $actor ) ) { |
| 348 |
$wp_query->set_404(); |
| 349 |
return; |
| 350 |
} |
| 351 |
|
| 352 |
if ( is_activitypub_request() ) { |
| 353 |
return; |
| 354 |
} |
| 355 |
|
| 356 |
\wp_safe_redirect( $actor->get_url(), 301 ); |
| 357 |
exit; |
| 358 |
} |
| 359 |
|
| 360 |
$term_id = \get_query_var( 'term_id', null ); |
| 361 |
if ( $term_id ) { |
| 362 |
$term = \get_term( $term_id ); |
| 363 |
|
| 364 |
// Load a 404-page if `term_id` is set but not valid. |
| 365 |
if ( ! $term || \is_wp_error( $term ) ) { |
| 366 |
$wp_query->set_404(); |
| 367 |
return; |
| 368 |
} |
| 369 |
|
| 370 |
/** |
| 371 |
* Filters the taxonomies supported for term redirects. |
| 372 |
* |
| 373 |
* @since 7.8.3 |
| 374 |
* |
| 375 |
* @param array $supported_taxonomies Array of taxonomy names. Default array( 'category', 'post_tag' ). |
| 376 |
*/ |
| 377 |
$supported_taxonomies = \apply_filters( 'activitypub_supported_taxonomies', array( 'category', 'post_tag' ) ); |
| 378 |
|
| 379 |
if ( ! \in_array( $term->taxonomy, $supported_taxonomies, true ) ) { |
| 380 |
return; |
| 381 |
} |
| 382 |
|
| 383 |
// Don't redirect for ActivityPub requests. |
| 384 |
if ( is_activitypub_request() ) { |
| 385 |
return; |
| 386 |
} |
| 387 |
|
| 388 |
$term_link = \get_term_link( $term ); |
| 389 |
if ( ! \is_wp_error( $term_link ) ) { |
| 390 |
\wp_safe_redirect( $term_link, 301 ); |
| 391 |
exit; |
| 392 |
} |
| 393 |
} |
| 394 |
} |
| 395 |
|
| 396 |
/** |
| 397 |
* Add the 'activitypub' query variable so WordPress won't mangle it. |
| 398 |
* |
| 399 |
* @param array $vars The query variables. |
| 400 |
* |
| 401 |
* @return array The query variables. |
| 402 |
*/ |
| 403 |
public static function add_query_vars( $vars ) { |
| 404 |
$vars[] = 'activitypub'; |
| 405 |
$vars[] = 'preview'; |
| 406 |
$vars[] = 'author'; |
| 407 |
$vars[] = 'actor'; |
| 408 |
$vars[] = 'stamp'; |
| 409 |
$vars[] = 'type'; |
| 410 |
$vars[] = 'c'; |
| 411 |
$vars[] = 'p'; |
| 412 |
$vars[] = 'term_id'; |
| 413 |
|
| 414 |
return $vars; |
| 415 |
} |
| 416 |
|
| 417 |
/** |
| 418 |
* Optimize home page query for ActivityPub requests. |
| 419 |
* |
| 420 |
* Skip the database query entirely for ActivityPub requests on the home page |
| 421 |
* since we only need to return the blog actor, not posts. |
| 422 |
* |
| 423 |
* @param \WP_Query $wp_query The WP_Query instance. |
| 424 |
*/ |
| 425 |
public static function fix_is_home_check( $wp_query ) { |
| 426 |
if ( |
| 427 |
$wp_query->get( 'actor' ) || |
| 428 |
$wp_query->get( 'stamp' ) || |
| 429 |
$wp_query->get( 'c' ) |
| 430 |
) { |
| 431 |
$wp_query->is_home = false; |
| 432 |
} |
| 433 |
} |
| 434 |
} |
| 435 |
|
