Ticket #47834: 47834.diff

src/wp-includes/rest-api/class-wp-rest-server.php

@@ -406 +406 @@
                                 return null;
                         }
 
-                        $result = wp_json_encode( $result );
+                        /**
+                         * Filters whether the result should be json encoded.
+                         *
+                         * Allows disabling json encoding of the result just before sending the response.
+                         * This can be useful if a content type other than application/json should be used to provide the resource.
+                         * For example:
+                         * - text/calendar iCalendar / ics files according to RFC 5545
+                         * - text/vcard Business Card information RFC 6350
+                         * - application/pdf PDF file content
+                         *
+                         * The header field must be set in your resource handler by calling header("Content-Type", "...")
+                         * on your response object.
+                         *
+                         * @since 5.3.0
+                         *
+                         * @param boolean          $do_encode Whether the result content should be passed to wp_json_encode() or not.
+                         *                                             Default true
+                         * @param WP_HTTP_Response $result    Result to send to the client. Usually a string or object.
+                         * @param WP_REST_Request  $request   Request used to generate the response.
+                         * @param WP_REST_Server   $this      Server instance.
+                         */
+                        $do_json_encode = apply_filters( 'rest_do_json_encode', true, $result, $request, $this );
+                        if ( $do_json_encode ) {
+                                $result = wp_json_encode( $result );
+                        }
 
                         $json_error_message = $this->get_json_last_error();
                         if ( $json_error_message ) {