wp_edit_theme_plugin_file

wp_edit_theme_plugin_file: 當在WordPress儀表盤上編輯一個主題或外掛檔案時，這個鉤子被觸發。這個鉤子可以用來修改檔案編輯器的行為，或者為編輯器新增新的功能。

試圖編輯一個主題或外掛的檔案。

當編輯一個PHP檔案時，將向管理員和主頁發出迴環請求，以嘗試檢視是否有一個致命的錯誤引入。如果是這樣，PHP的修改將被恢復。

function wp_edit_theme_plugin_file( $args ) {
	if ( empty( $args['file'] ) ) {
		return new WP_Error( 'missing_file' );
	}

	if ( 0 !== validate_file( $args['file'] ) ) {
		return new WP_Error( 'bad_file' );
	}

	if ( ! isset( $args['newcontent'] ) ) {
		return new WP_Error( 'missing_content' );
	}

	if ( ! isset( $args['nonce'] ) ) {
		return new WP_Error( 'missing_nonce' );
	}

	$file    = $args['file'];
	$content = $args['newcontent'];

	$plugin    = null;
	$theme     = null;
	$real_file = null;

	if ( ! empty( $args['plugin'] ) ) {
		$plugin = $args['plugin'];

		if ( ! current_user_can( 'edit_plugins' ) ) {
			return new WP_Error( 'unauthorized', __( 'Sorry, you are not allowed to edit plugins for this site.' ) );
		}

		if ( ! wp_verify_nonce( $args['nonce'], 'edit-plugin_' . $file ) ) {
			return new WP_Error( 'nonce_failure' );
		}

		if ( ! array_key_exists( $plugin, get_plugins() ) ) {
			return new WP_Error( 'invalid_plugin' );
		}

		if ( 0 !== validate_file( $file, get_plugin_files( $plugin ) ) ) {
			return new WP_Error( 'bad_plugin_file_path', __( 'Sorry, that file cannot be edited.' ) );
		}

		$editable_extensions = wp_get_plugin_file_editable_extensions( $plugin );

		$real_file = WP_PLUGIN_DIR . '/' . $file;

		$is_active = in_array(
			$plugin,
			(array) get_option( 'active_plugins', array() ),
			true
		);

	} elseif ( ! empty( $args['theme'] ) ) {
		$stylesheet = $args['theme'];

		if ( 0 !== validate_file( $stylesheet ) ) {
			return new WP_Error( 'bad_theme_path' );
		}

		if ( ! current_user_can( 'edit_themes' ) ) {
			return new WP_Error( 'unauthorized', __( 'Sorry, you are not allowed to edit templates for this site.' ) );
		}

		$theme = wp_get_theme( $stylesheet );
		if ( ! $theme->exists() ) {
			return new WP_Error( 'non_existent_theme', __( 'The requested theme does not exist.' ) );
		}

		if ( ! wp_verify_nonce( $args['nonce'], 'edit-theme_' . $stylesheet . '_' . $file ) ) {
			return new WP_Error( 'nonce_failure' );
		}

		if ( $theme->errors() && 'theme_no_stylesheet' === $theme->errors()->get_error_code() ) {
			return new WP_Error(
				'theme_no_stylesheet',
				__( 'The requested theme does not exist.' ) . ' ' . $theme->errors()->get_error_message()
			);
		}

		$editable_extensions = wp_get_theme_file_editable_extensions( $theme );

		$allowed_files = array();
		foreach ( $editable_extensions as $type ) {
			switch ( $type ) {
				case 'php':
					$allowed_files = array_merge( $allowed_files, $theme->get_files( 'php', -1 ) );
					break;
				case 'css':
					$style_files                = $theme->get_files( 'css', -1 );
					$allowed_files['style.css'] = $style_files['style.css'];
					$allowed_files              = array_merge( $allowed_files, $style_files );
					break;
				default:
					$allowed_files = array_merge( $allowed_files, $theme->get_files( $type, -1 ) );
					break;
			}
		}

		// Compare based on relative paths.
		if ( 0 !== validate_file( $file, array_keys( $allowed_files ) ) ) {
			return new WP_Error( 'disallowed_theme_file', __( 'Sorry, that file cannot be edited.' ) );
		}

		$real_file = $theme->get_stylesheet_directory() . '/' . $file;

		$is_active = ( get_stylesheet() === $stylesheet || get_template() === $stylesheet );

	} else {
		return new WP_Error( 'missing_theme_or_plugin' );
	}

	// Ensure file is real.
	if ( ! is_file( $real_file ) ) {
		return new WP_Error( 'file_does_not_exist', __( 'File does not exist! Please double check the name and try again.' ) );
	}

	// Ensure file extension is allowed.
	$extension = null;
	if ( preg_match( '/.([^.]+)$/', $real_file, $matches ) ) {
		$extension = strtolower( $matches[1] );
		if ( ! in_array( $extension, $editable_extensions, true ) ) {
			return new WP_Error( 'illegal_file_type', __( 'Files of this type are not editable.' ) );
		}
	}

	$previous_content = file_get_contents( $real_file );

	if ( ! is_writable( $real_file ) ) {
		return new WP_Error( 'file_not_writable' );
	}

	$f = fopen( $real_file, 'w+' );

	if ( false === $f ) {
		return new WP_Error( 'file_not_writable' );
	}

	$written = fwrite( $f, $content );
	fclose( $f );

	if ( false === $written ) {
		return new WP_Error( 'unable_to_write', __( 'Unable to write to file.' ) );
	}

	wp_opcache_invalidate( $real_file, true );

	if ( $is_active && 'php' === $extension ) {

		$scrape_key   = md5( rand() );
		$transient    = 'scrape_key_' . $scrape_key;
		$scrape_nonce = (string) rand();
		// It shouldn't take more than 60 seconds to make the two loopback requests.
		set_transient( $transient, $scrape_nonce, 60 );

		$cookies       = wp_unslash( $_COOKIE );
		$scrape_params = array(
			'wp_scrape_key'   => $scrape_key,
			'wp_scrape_nonce' => $scrape_nonce,
		);
		$headers       = array(
			'Cache-Control' => 'no-cache',
		);

		/** This filter is documented in wp-includes/class-wp-http-streams.php */
		$sslverify = apply_filters( 'https_local_ssl_verify', false );

		// Include Basic auth in loopback requests.
		if ( isset( $_SERVER['PHP_AUTH_USER'] ) && isset( $_SERVER['PHP_AUTH_PW'] ) ) {
			$headers['Authorization'] = 'Basic ' . base64_encode( wp_unslash( $_SERVER['PHP_AUTH_USER'] ) . ':' . wp_unslash( $_SERVER['PHP_AUTH_PW'] ) );
		}

		// Make sure PHP process doesn't die before loopback requests complete.
		set_time_limit( 5 * MINUTE_IN_SECONDS );

		// Time to wait for loopback requests to finish.
		$timeout = 100; // 100 seconds.

		$needle_start = "###### wp_scraping_result_start:$scrape_key ######";
		$needle_end   = "###### wp_scraping_result_end:$scrape_key ######";

		// Attempt loopback request to editor to see if user just whitescreened themselves.
		if ( $plugin ) {
			$url = add_query_arg( compact( 'plugin', 'file' ), admin_url( 'plugin-editor.php' ) );
		} elseif ( isset( $stylesheet ) ) {
			$url = add_query_arg(
				array(
					'theme' => $stylesheet,
					'file'  => $file,
				),
				admin_url( 'theme-editor.php' )
			);
		} else {
			$url = admin_url();
		}

		if ( function_exists( 'session_status' ) && PHP_SESSION_ACTIVE === session_status() ) {
			// Close any active session to prevent HTTP requests from timing out
			// when attempting to connect back to the site.
			session_write_close();
		}

		$url                    = add_query_arg( $scrape_params, $url );
		$r                      = wp_remote_get( $url, compact( 'cookies', 'headers', 'timeout', 'sslverify' ) );
		$body                   = wp_remote_retrieve_body( $r );
		$scrape_result_position = strpos( $body, $needle_start );

		$loopback_request_failure = array(
			'code'    => 'loopback_request_failed',
			'message' => __( 'Unable to communicate back with site to check for fatal errors, so the PHP change was reverted. You will need to upload your PHP file change by some other means, such as by using SFTP.' ),
		);
		$json_parse_failure       = array(
			'code' => 'json_parse_error',
		);

		$result = null;

		if ( false === $scrape_result_position ) {
			$result = $loopback_request_failure;
		} else {
			$error_output = substr( $body, $scrape_result_position + strlen( $needle_start ) );
			$error_output = substr( $error_output, 0, strpos( $error_output, $needle_end ) );
			$result       = json_decode( trim( $error_output ), true );
			if ( empty( $result ) ) {
				$result = $json_parse_failure;
			}
		}

		// Try making request to homepage as well to see if visitors have been whitescreened.
		if ( true === $result ) {
			$url                    = home_url( '/' );
			$url                    = add_query_arg( $scrape_params, $url );
			$r                      = wp_remote_get( $url, compact( 'cookies', 'headers', 'timeout', 'sslverify' ) );
			$body                   = wp_remote_retrieve_body( $r );
			$scrape_result_position = strpos( $body, $needle_start );

			if ( false === $scrape_result_position ) {
				$result = $loopback_request_failure;
			} else {
				$error_output = substr( $body, $scrape_result_position + strlen( $needle_start ) );
				$error_output = substr( $error_output, 0, strpos( $error_output, $needle_end ) );
				$result       = json_decode( trim( $error_output ), true );
				if ( empty( $result ) ) {
					$result = $json_parse_failure;
				}
			}
		}

		delete_transient( $transient );

		if ( true !== $result ) {
			// Roll-back file change.
			file_put_contents( $real_file, $previous_content );
			wp_opcache_invalidate( $real_file, true );

			if ( ! isset( $result['message'] ) ) {
				$message = __( 'Something went wrong.' );
			} else {
				$message = $result['message'];
				unset( $result['message'] );
			}

			return new WP_Error( 'php_error', $message, $result );
		}
	}

	if ( $theme instanceof WP_Theme ) {
		$theme->cache_delete();
	}

	return true;
}