Changeset 8287

Timestamp:

02/20/2019 01:06:00 AM (7 years ago)

Author:

coreymckrill

Message:

WordCamp: More improvements to error handling/logging

• Rename 0-slack.php to 0-error-handling.php, since that file's only purpose is to load the Slack library for error handling purposes anyway.
• Move all of the error handling stuff from wcorg-misc.php to 0-error-handling.php. There's enough of it to warrant a separate file, and this way it all gets loaded before the rest of the mu-plugins so it can potentially catch errors there as well.
• Run the custom error handler and shutdown function in other environments besides production, as long as the SANDBOX_SLACK_USERNAME constant is defined. This way the errors will be sent to the sandbox owner's Slack account, rather than the log channel.
• In the shutdown function, only send the error to Slack if it is one of the types of errors that can't be handled in the custom error handler.
• Modify the layout and contents of error messages sent to Slack to make them easier to parse when skimming through backscroll.

Location:

sites/trunk/wordcamp.org/public_html/wp-content/mu-plugins

Files:

• 0-error-handling.php (added)
• 0-slack.php (deleted)
• wcorg-misc.php (modified) (1 diff)

sites/trunk/wordcamp.org/public_html/wp-content/mu-plugins/wcorg-misc.php

@@ -443 +443 @@
 add_filter( 'map_meta_cap', 'wcorg_central_modify_export_caps', 10, 2 );
 
-define( 'ERROR_RATE_LIMITING_DIR', '/tmp/error_limiting' );
-
-/**
- * Check and create filesystem dirs to manage rate limiting in error handling.
- * For legacy bugs we are doing rate limiting via filesystem. We would be investigating to see if we can instead use memcache to rate limit sometime in the future.
- *
- * @return bool Return true if file permissions etc are present
- */
-function init_error_handling() {
-    if ( ! file_exists( ERROR_RATE_LIMITING_DIR ) ) {
-        mkdir( ERROR_RATE_LIMITING_DIR );
-    }
-
-    return is_dir( ERROR_RATE_LIMITING_DIR ) && is_writeable( ERROR_RATE_LIMITING_DIR );
-}
-
-/**
- * Error handler to send errors to slack. Always return false.
- */
-function send_error_to_slack( $err_no, $err_msg, $file, $line ) {
-    if ( ! init_error_handling() ) {
-        return false;
-    }
-
-    // Checks to see if the error-throwing expression is prepended with the @ control operator.
-    // See https://secure.php.net/manual/en/function.set-error-handler.php
-    if ( 0 === error_reporting() ) {
-        error_clear_last();
-
-        return false;
-    }
-
-    $error_safelist = [
-        E_ERROR,
-        E_USER_ERROR,
-        E_CORE_ERROR,
-        E_COMPILE_ERROR,
-        E_PARSE,
-        E_NOTICE,
-        E_DEPRECATED,
-        E_WARNING,
-    ];
-
-    if ( ! in_array( $err_no, $error_safelist ) ) {
-        return false;
-    }
-
-    // Always use constants in the keys here to avoid path disclosure.
-    $error_ignorelist = [
-        // See https://core.trac.wordpress.org/ticket/29204
-        ABSPATH . 'wp-includes/SimplePie/Registry.php:215' => 'Non-static method WP_Feed_Cache::create() should not be called statically',
-    ];
-
-    if ( isset( $error_ignorelist[ "$file:$line" ] ) && false !== strpos( $err_msg, $error_ignorelist[ "$file:$line" ] ) ) {
-        return false;
-    }
-
-    // Max file length for ubuntu system is 255.
-    $err_key = substr( base64_encode("$file-$line-$err_no" ), -254 );
-
-    $error_file = ERROR_RATE_LIMITING_DIR . "/$err_key";
-
-    $text = '';
-
-    $data = array(
-        'last_reported_at' => time(),
-        'error_count'      => 0, // since last reported.
-    );
-
-    if ( ! file_exists( $error_file ) ) {
-        $text = 'Error occured. ';
-        file_put_contents( $error_file, wp_json_encode( $data ) );
-    } else {
-        $data                 = json_decode( file_get_contents( $error_file ), true );
-        $data['error_count'] += 1;
-        $time_elasped         = time() - $data['last_reported_at'];
-
-        if ( $time_elasped > 600 ) {
-            $text                     = "Still happening. Happened ${data['error_count']} time(s) since last reported. ";
-            $data['last_reported_at'] = time();
-            $data['error_count']      = 0;
-
-            file_put_contents( $error_file, wp_json_encode( $data ) );
-        } else {
-            file_put_contents( $error_file, wp_json_encode( $data ) );
-            return false;
-        }
-    }
-
-    $domain    = get_site_url();
-    $page_slug = esc_html( trim( $_SERVER['REQUEST_URI'], '/' ) );
-    $text      = $text . "Message : \"$err_msg\" occurred on \"$file:$line\" \n Domain: $domain \n Page: $page_slug \n Error type: $err_no";
-
-    $message = array(
-        'fallback'    => $text,
-        'color'       => '#ff0000',
-        'pretext'     => "Error on \"$file:$line\" ",
-        'author_name' => $domain,
-        'text'        => $text,
-    );
-
-    $send = new \Dotorg\Slack\Send( SLACK_ERROR_REPORT_URL );
-    $send->add_attachment( $message );
-
-    $send->send( WORDCAMP_LOGS_SLACK_CHANNEL );
-
-    return false;
-}
-
-/**
- * Shutdown handler which forwards errors to slack.
- */
-function send_fatal_to_slack() {
-    $error = error_get_last();
-    if ( ! $error ) {
-        return;
-    }
-
-    return send_error_to_slack( $error['type'], $error['message'], $error['file'], $error['line'] );
-}
-
-if ( 'production' === WORDCAMP_ENVIRONMENT ) {
-    register_shutdown_function( 'send_fatal_to_slack' );
-    set_error_handler( 'send_error_to_slack', E_ERROR );
-}
-
-/**
- * Function `send_error_to_slack` above also creates a bunch of files in /tmp/error_limiting folder in order to rate limit the notification.
- * This function will be used as a cron to clear these error_limiting files periodically.
- */
-function handle_clear_error_rate_limiting_files() {
-    if ( ! init_error_handling() ) {
-        return;
-    }
-
-    foreach ( new DirectoryIterator( ERROR_RATE_LIMITING_DIR ) as $file_info ) {
-        if ( ! $file_info->isDot() ) {
-            unlink( $file_info->getPathname() );
-        }
-    }
-
-}
-
-add_action( 'clear_error_rate_limiting_files', 'handle_clear_error_rate_limiting_files' );
-
-if ( ! wp_next_scheduled( 'clear_error_rate_limiting_files' ) ) {
-    wp_schedule_event( time(), 'daily', 'clear_error_rate_limiting_files' );
-}
-
 /**
  * Allow individual site administrators to activate and deactivate optional plugins.