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<?php |
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/** |
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* Site Health self-check for the .well-known OAuth discovery documents. |
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* |
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* On hosts that provision a physical `.well-known/acme-challenge/` directory |
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* for Let's Encrypt auto-SSL (OVH, cPanel/AutoSSL, Plesk, and most managed-WP |
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* hosts), the web server can 404 sibling `.well-known/oauth-*` paths before |
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* WordPress ever runs — see the README "Hosting: .well-known conflicts" |
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* section. No WordPress-level code change can influence that; this class is |
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* a passive diagnostic only, registered as a single `direct` WordPress Site |
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* Health test (the `site_status_tests` filter) that issues a loopback request |
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* to both RFC discovery documents (`Endpoints`) and reports one combined |
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* status. |
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*/ |
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|
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declare(strict_types=1); |
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|
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namespace WPMedia\MCP\OAuth\Auth\Discovery; |
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|
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use WP_Error; |
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use WPMedia\MCP\OAuth\Context; |
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|
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class HealthCheck { |
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|
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/** |
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* Site Health test key registered under the `direct` bucket. |
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*/ |
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const TEST_KEY = 'wpmedia_mcp_oauth_wellknown_discovery'; |
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|
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/** |
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* Transient key caching the combined self-check result. |
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*/ |
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const TRANSIENT_KEY = 'wpmedia_mcp_oauth_wellknown_health_check'; |
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|
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/** |
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* Cache TTL, in seconds, for the combined self-check result. |
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*/ |
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const TRANSIENT_TTL = 5 * MINUTE_IN_SECONDS; |
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|
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/** |
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* Per-request timeout, in seconds, for each loopback discovery request. |
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*/ |
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const FETCH_TIMEOUT = 5; |
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|
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/** |
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* Relative discovery document paths, keyed by a short display name. |
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* |
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* @var array<string, string> |
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*/ |
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private const DOCUMENTS = [ |
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'oauth-protected-resource' => '/.well-known/oauth-protected-resource', |
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'oauth-authorization-server' => '/.well-known/oauth-authorization-server', |
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]; |
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|
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/** |
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* Status severity used to pick the combined result. |
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* |
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* @var array<string, int> |
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*/ |
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private const STATUS_RANK = [ |
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'good' => 0, |
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'recommended' => 1, |
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'critical' => 2, |
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]; |
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|
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/** |
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* OAuth server context. |
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* |
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* @var Context |
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*/ |
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private Context $context; |
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|
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/** |
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* Constructor. |
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* |
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* @param Context $context OAuth server context. |
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*/ |
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public function __construct( Context $context ) { |
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$this->context = $context; |
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} |
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|
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/** |
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* Register the combined discovery-document self-check as a `direct` Site Health test. |
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* |
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* @param array<string, array<string, array<string, mixed>>> $tests Existing Site Health tests, keyed by bucket ('direct'|'async'). |
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* @return array<string, array<string, array<string, mixed>>> Modified tests. |
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*/ |
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public function add_test( array $tests ): array { |
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$tests['direct'][ self::TEST_KEY ] = [ |
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'label' => __( 'MCP OAuth discovery documents', 'mcp-oauth' ), |
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'test' => [ $this, 'run_self_check' ], |
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]; |
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|
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return $tests; |
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} |
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|
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/** |
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* Run the combined discovery-document self-check. |
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* |
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* @return array<string, mixed> Site Health test result (label, status, badge, description, actions, test). |
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*/ |
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public function run_self_check(): array { |
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if ( ! $this->context->is_enabled() ) { |
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return $this->build_result( |
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'good', |
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[], |
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__( 'The MCP OAuth server is intentionally disabled (the <code>wpmedia_mcp_oauth_server_enabled</code> filter returns false), so the .well-known discovery documents are not expected to be reachable.', 'mcp-oauth' ) |
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); |
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} |
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|
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if ( '' === (string) get_option( 'permalink_structure' ) ) { |
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return $this->build_result( |
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'recommended', |
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[], |
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__( 'The .well-known OAuth discovery documents are served through a rewrite rule, which requires a pretty permalink structure. Enable one under Settings → Permalinks, then re-check this test.', 'mcp-oauth' ) |
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); |
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} |
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|
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$cached = get_transient( self::TRANSIENT_KEY ); |
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if ( is_array( $cached ) ) { |
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return $cached; |
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} |
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|
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$worst_status = 'good'; |
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$failing = []; |
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|
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foreach ( self::DOCUMENTS as $name => $path ) { |
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$response = wp_safe_remote_get( |
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home_url( $path ), |
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[ |
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'timeout' => self::FETCH_TIMEOUT, |
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] |
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); |
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|
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$status = $this->classify( $response ); |
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|
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if ( self::STATUS_RANK[ $status ] > self::STATUS_RANK[ $worst_status ] ) { |
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$worst_status = $status; |
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} |
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|
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if ( 'good' !== $status ) { |
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$failing[] = $name; |
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} |
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} |
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|
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$result = $this->build_result( $worst_status, $failing ); |
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|
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set_transient( self::TRANSIENT_KEY, $result, self::TRANSIENT_TTL ); |
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|
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return $result; |
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} |
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|
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/** |
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* Classify a single document's fetch result into a Site Health status. |
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* |
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* @param array<string, mixed>|WP_Error $response The wp_remote_get() response array, or a WP_Error. |
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* @return string One of 'good', 'recommended', 'critical'. |
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*/ |
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private function classify( $response ): string { |
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if ( is_wp_error( $response ) ) { |
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return 'recommended'; |
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} |
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|
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$status_code = (int) wp_remote_retrieve_response_code( $response ); |
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|
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if ( in_array( $status_code, [ 401, 403, 407 ], true ) ) { |
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return 'recommended'; |
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} |
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|
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if ( 404 === $status_code ) { |
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$powered_by = (string) wp_remote_retrieve_header( $response, 'x-powered-by' ); |
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$redirect_by = (string) wp_remote_retrieve_header( $response, 'x-redirect-by' ); |
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|
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if ( '' === $powered_by && false === stripos( $redirect_by, 'WordPress' ) ) { |
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return 'critical'; |
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} |
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|
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return 'recommended'; |
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} |
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|
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if ( 200 === $status_code ) { |
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$body = (string) wp_remote_retrieve_body( $response ); |
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$decoded = json_decode( $body, true ); |
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|
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if ( is_array( $decoded ) ) { |
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return 'good'; |
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} |
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} |
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|
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return 'recommended'; |
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} |
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|
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/** |
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* Build the Site Health result array for a given combined status. |
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* |
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* @param string $status One of 'good', 'recommended', 'critical'. |
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* @param string[] $failing Display names of the documents that did not report 'good'. |
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* @param string $summary Optional override for the description's leading sentence |
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* (used by the disabled/plain-permalinks short-circuits). |
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* @return array<string, mixed> |
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*/ |
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private function build_result( string $status, array $failing, string $summary = '' ): array { |
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$loopback_caveat = __( 'This check runs from the server to itself. A "Good" result here does not guarantee external clients can reach these documents: a CDN, WAF, or reverse proxy in front of the site can still 404 these paths for external traffic while the server\'s own loopback request bypasses it. Verify with an external <code>curl</code> request after applying any server-config change.', 'mcp-oauth' ); |
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|
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/* |
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* The acme-challenge fingerprint is classified 'critical' internally so |
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* the detailed guidance below is selected, but it is reported to Site |
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* Health as 'recommended': the .well-known discovery documents are an |
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* optional MCP feature, and a "critical" badge generates support tickets |
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* for what is a non-blocking misconfiguration. |
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*/ |
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$reported_status = 'critical' === $status ? 'recommended' : $status; |
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|
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if ( '' !== $summary ) { |
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$description = sprintf( '<p>%s</p>', $summary ); |
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$actions = sprintf( '<p>%s</p>', $loopback_caveat ); |
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} elseif ( 'good' === $status ) { |
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$description = sprintf( |
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'<p>%s</p>', |
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__( 'Both .well-known OAuth discovery documents (oauth-protected-resource and oauth-authorization-server) responded with HTTP 200 and valid JSON.', 'mcp-oauth' ) |
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); |
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$actions = sprintf( '<p>%s</p>', $loopback_caveat ); |
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} else { |
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$document_list = implode( ', ', $failing ); |
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|
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if ( 'critical' === $status ) { |
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$description = sprintf( |
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'<p>%s</p>', |
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sprintf( |
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/* translators: %s: comma-separated list of failing discovery document names. */ |
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__( 'The following .well-known discovery document(s) returned a bare 404 with no WordPress-originated response header: %s. This matches the fingerprint of a physical .well-known/acme-challenge/ directory (provisioned by the host for Let\'s Encrypt auto-SSL) intercepting the request before WordPress runs — likely the cause here, though this should be confirmed against the actual .well-known/acme-challenge/ directory on the server before concluding root cause.', 'mcp-oauth' ), |
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esc_html( $document_list ) |
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) |
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); |
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|
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$actions = sprintf( |
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'<p>%s</p><p>%s</p><p>%s</p>', |
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__( 'Apply the Apache or Nginx snippet from this library\'s README ("Hosting: .well-known conflicts") to re-enable routing for these two paths without touching acme-challenge/.', 'mcp-oauth' ), |
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__( 'If a CDN or page cache is in front of the site, purge it after applying the fix — a stale cached 404 for these paths can otherwise persist even once the server config is corrected.', 'mcp-oauth' ), |
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$loopback_caveat |
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); |
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} else { |
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$description = sprintf( |
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'<p>%s</p>', |
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sprintf( |
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/* translators: %s: comma-separated list of failing discovery document names. */ |
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__( 'The following .well-known discovery document(s) did not respond as expected: %s. This does not match the confirmed .well-known/acme-challenge/ interception fingerprint, so the cause is inconclusive from this check alone (it may be a timeout, an access wall such as HTTP Basic Auth or a WAF, or a WordPress-served error).', 'mcp-oauth' ), |
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esc_html( $document_list ) |
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) |
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); |
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|
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$actions = sprintf( |
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'<p>%s</p><p>%s</p>', |
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__( 'Check your error/access logs for the requests to these paths, and rule out an authentication wall (staging HTTP Basic Auth, a WAF, or bot mitigation) before assuming a routing problem.', 'mcp-oauth' ), |
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$loopback_caveat |
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); |
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} |
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} |
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|
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return [ |
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'label' => __( 'MCP OAuth discovery documents', 'mcp-oauth' ), |
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'status' => $reported_status, |
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'badge' => [ |
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'label' => __( 'Configuration', 'mcp-oauth' ), |
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'color' => 'blue', |
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], |
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'description' => $description, |
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'actions' => $actions, |
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'test' => self::TEST_KEY, |
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]; |
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} |
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} |
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|
