Implement basic integration with Query Monitor

Author: JanJakes

integrations/query-monitor/boot.php

@@ -0,0 +1,113 @@
+<?php
+
+/**
+ * Boot Query Monitor from the SQLite Database Integration plugin.
+ *
+ * When the Query Monitor plugin exists in its standard location, let's check
+ * if it is active, so we can boot it eagerly. This is a workaround to avoid
+ * SQLite and Query Monitor competing for the "wp-content/db.php" file.
+ *
+ * This file is a modified version of the original Query Monitor "db.php" file.
+ *
+ * See: https://github.com/johnbillion/query-monitor/blob/develop/wp-content/db.php
+ */
+
+// 1. Check if we should load Query Monitor (as per the original "db.php" file).
+if ( ! defined( 'ABSPATH' ) ) {
+	exit;
+}
+
+if ( ! defined( 'DB_USER' ) ) {
+	return;
+}
+
+if ( defined( 'QM_DISABLED' ) && QM_DISABLED ) {
+	return;
+}
+
+if ( defined( 'WP_INSTALLING' ) && WP_INSTALLING ) {
+	return;
+}
+
+if ( 'cli' === php_sapi_name() && ! defined( 'QM_TESTS' ) ) {
+	return;
+}
+
+if ( defined( 'DOING_CRON' ) && DOING_CRON ) {
+	return;
+}
+
+if ( is_admin() ) {
+	if ( isset( $_GET['action'] ) && 'upgrade-plugin' === $_GET['action'] ) {
+		return;
+	}
+
+	if ( isset( $_POST['action'] ) && 'update-plugin' === $_POST['action'] ) {
+		return;
+	}
+}
+
+// 2. Check if Query Monitor is active.
+if ( null === $wpdb->options ) {
+	global $table_prefix;
+	$wpdb->set_prefix( $table_prefix ?? '' );
+}
+
+$query_monitor_active = false;
+try {
+	$value                = $wpdb->get_row(
+		$wpdb->prepare(
+			"SELECT option_value FROM $wpdb->options WHERE option_name = %s LIMIT 1",
+			'active_plugins'
+		)
+	);
+	$query_monitor_active = in_array(
+		'query-monitor/query-monitor.php',
+		unserialize( $value->option_value ),
+		true
+	);
+} catch ( Throwable $e ) {
+	return;
+}
+
+if ( ! $query_monitor_active ) {
+	return;
+}
+
+// 3. Determine the plugins directory.
+if ( defined( 'WP_PLUGIN_DIR' ) ) {
+	$plugins_dir = WP_PLUGIN_DIR;
+} else {
+	$plugins_dir = WP_CONTENT_DIR . '/plugins';
+}
+
+// 4. Load Query Monitor (as per the original "db.php" file).
+$qm_dir = "{$plugins_dir}/query-monitor";
+$qm_php = "{$qm_dir}/classes/PHP.php";
+
+if ( ! is_readable( $qm_php ) ) {
+	return;
+}
+require_once $qm_php;
+
+if ( ! QM_PHP::version_met() ) {
+	return;
+}
+
+if ( ! file_exists( "{$qm_dir}/vendor/autoload.php" ) ) {
+	add_action( 'all_admin_notices', 'QM_PHP::vendor_nope' );
+	return;
+}
+
+require_once "{$qm_dir}/vendor/autoload.php";
+
+if ( ! class_exists( 'QM_Backtrace' ) ) {
+	return;
+}
+
+if ( ! defined( 'SAVEQUERIES' ) ) {
+	define( 'SAVEQUERIES', true );
+}
+
+// 5. Mark the Query Monitor integration as loaded.
+define( 'SQLITE_QUERY_MONITOR_LOADED', true );

wp-includes/sqlite/class-wp-sqlite-db.php

@@ -408,6 +408,12 @@ public function prepare( $query, ...$args ) {
 	 *                  affected/selected for all other queries. Boolean false on error.
 	 */
 	public function query( $query ) {
+		// Query Monitor integration:
+		$query_monitor_active = defined( 'SQLITE_QUERY_MONITOR_LOADED' ) && SQLITE_QUERY_MONITOR_LOADED;
+		if ( $query_monitor_active && $this->show_errors ) {
+			$this->hide_errors();
+		}
+
 		if ( ! $this->ready ) {
 			return false;
 		}
@@ -427,6 +433,9 @@ public function query( $query ) {
 		// Keep track of the last query for debug.
 		$this->last_query = $query;
 
+		// Save the query count before running another query.
+		$last_query_count = count( $this->queries ?? array() );
+
 		/*
 		 * @TODO: WPDB uses "$this->check_current_query" to check table/column
 		 *        charset and strip all invalid characters from the query.
@@ -478,6 +487,28 @@ public function query( $query ) {
 			$return_val     = $num_rows;
 		}
 
+		// Query monitor integration:
+		if ( $query_monitor_active && class_exists( 'QM_Backtrace' ) ) {
+			if ( did_action( 'qm/cease' ) ) {
+				$this->queries = array();
+			}
+
+			$i = $last_query_count;
+			if ( ! isset( $this->queries[ $i ] ) ) {
+				return $return_val;
+			}
+
+			$this->queries[ $i ]['trace'] = new QM_Backtrace();
+			if ( ! isset( $this->queries[ $i ][3] ) ) {
+				$this->queries[ $i ][3] = $this->time_start;
+			}
+
+			if ( $this->last_error && ! $this->suppress_errors ) {
+				$this->queries[ $i ]['result'] = new WP_Error( 'qmdb', $this->last_error );
+			} else {
+				$this->queries[ $i ]['result'] = (int) $return_val;
+			}
+		}
 		return $return_val;
 	}
 

wp-includes/sqlite/db.php

@@ -67,4 +67,7 @@
 	$GLOBALS['wpdb'] = new WP_SQLite_Crosscheck_DB( DB_NAME );
 } else {
 	$GLOBALS['wpdb'] = new WP_SQLite_DB( defined( 'DB_NAME' ) ? DB_NAME : '' );
+
+	// Boot the Query Monitor plugin if it is active.
+	require_once dirname( __DIR__, 2 ) . '/integrations/query-monitor/boot.php';
 }