244 lines
6.6 KiB
PHP
244 lines
6.6 KiB
PHP
<?php
|
|
/**
|
|
* Class Output_Buffer
|
|
*
|
|
* @link https://github.com/googleforcreators/web-stories-wp
|
|
*
|
|
* @copyright 2021 Google LLC
|
|
* @license https://www.apache.org/licenses/LICENSE-2.0 Apache License 2.0
|
|
*/
|
|
|
|
/**
|
|
* Copyright 2021 Google LLC
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* https://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
declare(strict_types = 1);
|
|
|
|
namespace Google\Web_Stories\AMP;
|
|
|
|
use Google\Web_Stories\Context;
|
|
use Google\Web_Stories\Exception\SanitizationException;
|
|
use Google\Web_Stories\Infrastructure\Conditional;
|
|
use Google\Web_Stories\Service_Base;
|
|
use Google\Web_Stories_Dependencies\AmpProject\Dom\Document;
|
|
use Throwable;
|
|
|
|
/**
|
|
* Output buffer class.
|
|
*
|
|
* Largely copied from AMP_Theme_Support.
|
|
*
|
|
* @since 1.10.0
|
|
*
|
|
* @see \AMP_Theme_Support
|
|
*/
|
|
class Output_Buffer extends Service_Base implements Conditional {
|
|
|
|
/**
|
|
* Whether output buffering has started.
|
|
*/
|
|
protected bool $is_output_buffering = false;
|
|
|
|
/**
|
|
* Sanitization instance.
|
|
*
|
|
* @var Sanitization Sanitization instance.
|
|
*/
|
|
private Sanitization $sanitization;
|
|
|
|
/**
|
|
* Optimization instance.
|
|
*
|
|
* @var Optimization Optimization instance.
|
|
*/
|
|
private Optimization $optimization;
|
|
|
|
/**
|
|
* Context instance.
|
|
*
|
|
* @var Context Context instance.
|
|
*/
|
|
private Context $context;
|
|
|
|
/**
|
|
* Output_Buffer constructor.
|
|
*
|
|
* @since 1.10.0
|
|
*
|
|
* @param Sanitization $sanitization Sanitization instance.
|
|
* @param Optimization $optimization Optimization instance.
|
|
* @param Context $context Context instance.
|
|
*/
|
|
public function __construct( Sanitization $sanitization, Optimization $optimization, Context $context ) {
|
|
$this->sanitization = $sanitization;
|
|
$this->optimization = $optimization;
|
|
$this->context = $context;
|
|
}
|
|
|
|
/**
|
|
* Runs on instantiation.
|
|
*
|
|
* @since 1.10.0
|
|
*/
|
|
public function register(): void {
|
|
/*
|
|
* Start output buffering at very low priority for sake of plugins and themes that use template_redirect
|
|
* instead of template_include.
|
|
*/
|
|
$this->start_output_buffering();
|
|
}
|
|
|
|
/**
|
|
* Get the action to use for registering the service.
|
|
*
|
|
* @since 1.10.0
|
|
*
|
|
* @return string Registration action to use.
|
|
*/
|
|
public static function get_registration_action(): string {
|
|
return 'template_redirect';
|
|
}
|
|
|
|
/**
|
|
* Get the action priority to use for registering the service.
|
|
*
|
|
* @since 1.10.0
|
|
*
|
|
* @return int Registration action priority to use.
|
|
*/
|
|
public static function get_registration_action_priority(): int {
|
|
return PHP_INT_MIN;
|
|
}
|
|
|
|
/**
|
|
* Check whether the conditional object is currently needed.
|
|
*
|
|
* If the AMP plugin is installed and available in a version >= than ours,
|
|
* all sanitization and optimization should be delegated to the AMP plugin.
|
|
* But ONLY if AMP logic has not been disabled through any of its available filters.
|
|
*
|
|
* @since 1.10.0
|
|
*
|
|
* @return bool Whether the conditional object is needed.
|
|
*/
|
|
public static function is_needed(): bool {
|
|
$current_post = get_post();
|
|
|
|
$has_old_amp_version = ! \defined( '\AMP__VERSION' ) || ( \defined( '\AMP__VERSION' ) && version_compare( \AMP__VERSION, WEBSTORIES_AMP_VERSION, '<' ) );
|
|
$amp_available = \function_exists( 'amp_is_available' ) && amp_is_available();
|
|
$amp_enabled = \function_exists( 'amp_is_enabled' ) && amp_is_enabled(); // Technically an internal method.
|
|
$amp_initialized = did_action( 'amp_init' ) > 0;
|
|
$amp_supported_post = \function_exists( 'amp_is_post_supported' ) && amp_is_post_supported( $current_post->ID ?? 0 );
|
|
|
|
return $has_old_amp_version || ! $amp_available || ! $amp_enabled || ! $amp_initialized || ! $amp_supported_post;
|
|
}
|
|
|
|
/**
|
|
* Start output buffering.
|
|
*
|
|
* @since 1.10.0
|
|
*
|
|
* @see Output_Buffer::finish_output_buffering()
|
|
*/
|
|
public function start_output_buffering(): void {
|
|
if ( ! $this->context->is_web_story() ) {
|
|
return;
|
|
}
|
|
|
|
ob_start( [ $this, 'finish_output_buffering' ] );
|
|
$this->is_output_buffering = true;
|
|
}
|
|
|
|
/**
|
|
* Determine whether output buffering has started.
|
|
*
|
|
* @since 1.10.0
|
|
*
|
|
* @see Output_Buffer::start_output_buffering()
|
|
* @see Output_Buffer::finish_output_buffering()
|
|
*
|
|
* @return bool Whether output buffering has started.
|
|
*/
|
|
public function is_output_buffering(): bool {
|
|
return $this->is_output_buffering;
|
|
}
|
|
|
|
/**
|
|
* Finish output buffering.
|
|
*
|
|
* @since 1.10.0
|
|
*
|
|
* @see Output_Buffer::start_output_buffering()
|
|
*
|
|
* @param string $response Buffered Response.
|
|
* @return string Processed Response.
|
|
*/
|
|
public function finish_output_buffering( string $response ): string {
|
|
$this->is_output_buffering = false;
|
|
|
|
try {
|
|
$response = $this->prepare_response( $response );
|
|
} catch ( \Error $error ) { // Only PHP 7+.
|
|
$response = $this->render_error_page( $error );
|
|
} catch ( \Exception $exception ) {
|
|
$response = $this->render_error_page( $exception );
|
|
}
|
|
|
|
return $response;
|
|
}
|
|
|
|
/**
|
|
* Process response to ensure AMP validity.
|
|
*
|
|
* @since 1.10.0
|
|
*
|
|
* @param string $response HTML document response. By default it expects a complete document.
|
|
* @return string AMP document response.
|
|
*/
|
|
public function prepare_response( string $response ): string {
|
|
// Enforce UTF-8 encoding as it is a requirement for AMP.
|
|
if ( ! headers_sent() ) {
|
|
header( 'Content-Type: text/html; charset=utf-8' );
|
|
}
|
|
|
|
$dom = Document::fromHtml( $response );
|
|
|
|
if ( ! $dom instanceof Document ) {
|
|
return $this->render_error_page( SanitizationException::from_document_parse_error() );
|
|
}
|
|
|
|
$this->sanitization->sanitize_document( $dom );
|
|
$this->optimization->optimize_document( $dom );
|
|
|
|
return $dom->saveHTML();
|
|
}
|
|
|
|
/**
|
|
* Render error page.
|
|
*
|
|
* @since 1.10.0
|
|
*
|
|
* @param Throwable $throwable Exception or (as of PHP7) Error.
|
|
* @return string Error page.
|
|
*/
|
|
private function render_error_page( Throwable $throwable ): string {
|
|
return esc_html__( 'There was an error generating the web story, probably because of a server misconfiguration. Try contacting your hosting provider or open a new support request.', 'web-stories' ) .
|
|
"\n" .
|
|
"\n" .
|
|
// translators: 1: error message. 2: location.
|
|
sprintf( esc_html__( 'Error message: %1$s (%2$s)', 'web-stories' ), $throwable->getMessage(), $throwable->getFile() . ':' . $throwable->getLine() );
|
|
}
|
|
}
|