docs: Add database query timing documentation and dashboard panel (v0.4.7)

- Add Query Duration Distribution panel to Grafana Runtime dashboard
- Add wordpress_db_query_duration_seconds to Help tab metrics reference
- Add SAVEQUERIES documentation section to README
- Update translation files with new strings

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

CHANGELOG.md

@@ -5,6 +5,36 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.4.7] - 2026-02-03
+
+### Added
+
+- Database query duration distribution panel in Grafana Runtime dashboard
+- `wordpress_db_query_duration_seconds` metric now listed in Help tab
+- Documentation for enabling `SAVEQUERIES` constant for query timing
+
+### Changed
+
+- Updated README with instructions for enabling database query timing
+- Grafana Runtime dashboard now includes bucket distribution chart for DB queries
+
+## [0.4.6] - 2026-02-03
+
+### Added
+
+- Dashboard extension hook `wp_prometheus_register_dashboards` for third-party plugins
+- Third-party plugins can now register their own Grafana dashboard templates
+- Support for file-based and inline JSON dashboard registration
+- "Extension" badge for third-party dashboards in admin UI
+- Plugin attribution display for third-party dashboards
+- Security: Path traversal protection for registered dashboard files
+- Isolated mode support for dashboard registration hook
+
+### Changed
+
+- DashboardProvider now supports both built-in and third-party registered dashboards
+- Dashboard cards show source (built-in vs extension) with visual distinction
+
 ## [0.4.5] - 2026-02-02
 
 ### Fixed

CLAUDE.md

@@ -23,6 +23,7 @@ This plugin provides a Prometheus `/metrics` endpoint and an extensible way to a
 - Grafana dashboard templates for easy visualization
 - Dedicated plugin settings under 'Settings/Metrics' menu
 - Extensible by other plugins using `wp_prometheus_collect_metrics` action hook
+- Dashboard extension hook `wp_prometheus_register_dashboards` for third-party Grafana dashboards
 - License management integration
 
 ### Key Fact: 100% AI-Generated
@@ -33,7 +34,7 @@ This project is proudly **"vibe-coded"** using Claude.AI - the entire codebase w
 
 **Note for AI Assistants:** Clean this section after the specific features are done or new releases are made. Effective changes are tracked in `CHANGELOG.md`. Do not add completed versions here - document them in the Session History section at the end of this file.
 
-*No planned features at this time.*
+*No pending roadmap items.*
 
 ## Technical Stack
 
@@ -291,6 +292,44 @@ add_action( 'wp_prometheus_collect_metrics', function( $collector ) {
 
 ## Session History
 
+### 2026-02-03 - Database Query Timing Documentation (v0.4.7)
+
+- Added database query duration distribution panel to Grafana Runtime dashboard
+- Added `wordpress_db_query_duration_seconds` metric to Help tab metrics reference
+- Added documentation in README explaining how to enable `SAVEQUERIES` for query timing
+- Updated translation files (.pot and .po) with new strings
+- **Key Learning**: WordPress `SAVEQUERIES` constant
+  - Enables `$wpdb->queries` array with query strings, timing, and call stacks
+  - Required for `wordpress_db_query_duration_seconds` histogram metric
+  - Has performance overhead - recommended for development, use cautiously in production
+  - Without it, only query counts are available (not timing data)
+
+### 2026-02-03 - Dashboard Extension Hook (v0.4.6)
+
+- Added `wp_prometheus_register_dashboards` action hook for third-party plugins
+- Third-party plugins can now register their own Grafana dashboard templates
+- Implementation in `DashboardProvider.php`:
+  - `register_dashboard(slug, args)` method for registrations
+  - Supports file-based dashboards (absolute path to JSON) or inline JSON content
+  - Security: Path traversal protection (files must be under `WP_CONTENT_DIR`)
+  - `fire_registration_hook()` with output buffering and exception handling
+  - Respects isolated mode setting (skips third-party hooks when enabled)
+  - `is_third_party()` and `get_plugin_name()` helper methods
+- Updated admin UI in Settings.php:
+  - "Extension" badge displayed on third-party dashboard cards
+  - Plugin attribution shown below third-party dashboards
+  - Visual distinction with blue border for third-party cards
+- **Key Learning**: Extension hook design pattern
+  - Fire hook lazily on first `get_available()` call, not in constructor
+  - Use `$hook_fired` flag to prevent double-firing
+  - Wrap hook execution in try-catch to isolate failures
+  - Validate registrations thoroughly before accepting them
+- **Key Learning**: Security for file-based registrations
+  - Require absolute paths (`path_is_absolute()`)
+  - Validate files exist and are readable
+  - Use `realpath()` to resolve symlinks and prevent traversal
+  - Restrict to `WP_CONTENT_DIR` (not just plugin directories)
+
 ### 2026-02-02 - Settings Persistence Fix (v0.4.5)
 
 - Fixed critical bug where settings would get cleared when saving from different Metrics sub-tabs

README.md

@@ -6,7 +6,13 @@ A WordPress plugin that provides a Prometheus-compatible `/metrics` endpoint wit
 
 - Prometheus-compatible authenticated `/metrics` endpoint
 - Default WordPress metrics (users, posts, comments, plugins)
+- Runtime metrics (HTTP requests, database queries)
+- Cron job and transient cache metrics
+- WooCommerce integration (products, orders, revenue)
+- Custom metric builder with admin UI
+- Grafana dashboard templates with download
 - Extensible by other plugins using hooks
+- Dashboard extension hook for third-party Grafana dashboards
 - Settings page under Settings > Metrics
 - Bearer token authentication
 - License management integration
@@ -92,6 +98,21 @@ scrape_configs:
 
 **Note:** Runtime metrics aggregate data across requests. Enable only the metrics you need to minimize performance impact.
 
+#### Enabling Database Query Timing
+
+The `wordpress_db_query_duration_seconds` histogram requires WordPress's `SAVEQUERIES` constant to be enabled. Add this to your `wp-config.php`:
+
+```php
+define( 'SAVEQUERIES', true );
+```
+
+**Important considerations:**
+
+- `SAVEQUERIES` has a performance overhead as it logs all queries with timing and call stacks
+- Recommended for development/staging environments, use with caution in production
+- Without `SAVEQUERIES`, only query counts (`wordpress_db_queries_total`) are available
+- The histogram shows total query time per request, grouped by endpoint
+
 ### Cron Metrics (v0.2.0+)
 
 | Metric | Type | Labels | Description |
@@ -154,6 +175,51 @@ $histogram = $collector->register_histogram( $name, $help, $labels, $buckets );
 $histogram->observe( $value, $labelValues );
 ```
 
+## Extending with Custom Dashboards (v0.4.6+)
+
+Add your own Grafana dashboard templates using the `wp_prometheus_register_dashboards` action:
+
+```php
+add_action( 'wp_prometheus_register_dashboards', function( $provider ) {
+    // File-based dashboard
+    $provider->register_dashboard( 'my-plugin-dashboard', array(
+        'title'       => __( 'My Plugin Metrics', 'my-plugin' ),
+        'description' => __( 'Dashboard for my custom metrics', 'my-plugin' ),
+        'icon'        => 'dashicons-chart-bar',
+        'file'        => MY_PLUGIN_PATH . 'assets/dashboards/my-dashboard.json',
+        'plugin'      => 'My Plugin Name',
+    ) );
+
+    // OR inline JSON dashboard
+    $provider->register_dashboard( 'dynamic-dashboard', array(
+        'title'       => __( 'Dynamic Dashboard', 'my-plugin' ),
+        'description' => __( 'Dynamically generated dashboard', 'my-plugin' ),
+        'icon'        => 'dashicons-admin-generic',
+        'json'        => json_encode( $dashboard_array ),
+        'plugin'      => 'My Plugin Name',
+    ) );
+} );
+```
+
+### Registration Parameters
+
+| Parameter | Required | Description |
+| --------- | -------- | ----------- |
+| `title` | Yes | Dashboard title displayed in admin |
+| `description` | No | Description shown below the title |
+| `icon` | No | Dashicon class (default: `dashicons-chart-line`) |
+| `file` | Yes* | Absolute path to JSON file |
+| `json` | Yes* | Inline JSON content |
+| `plugin` | No | Plugin name for attribution |
+
+*Either `file` or `json` is required, but not both.
+
+### Security Notes
+
+- File paths must be absolute and within `wp-content/`
+- Inline JSON is validated during registration
+- Third-party dashboards are marked with an "Extension" badge in the admin UI
+
 ## Development
 
 ### Build for Release

assets/css/admin.css

@@ -216,6 +216,32 @@
     font-size: 13px;
 }
 
+/* Third-party dashboard card styling */
+.wp-prometheus-dashboard-card.third-party {
+    position: relative;
+    border-color: #2271b1;
+}
+
+.wp-prometheus-dashboard-card .dashboard-badge {
+    position: absolute;
+    top: -8px;
+    right: -8px;
+    background: #2271b1;
+    color: #fff;
+    font-size: 10px;
+    font-weight: 600;
+    padding: 3px 8px;
+    border-radius: 10px;
+    text-transform: uppercase;
+    letter-spacing: 0.5px;
+}
+
+.wp-prometheus-dashboard-card .dashboard-plugin {
+    color: #646970;
+    margin: -5px 0 15px 0;
+    font-style: italic;
+}
+
 /* Import options panel */
 #import-options {
     border-radius: 4px;

assets/dashboards/wordpress-runtime.json

@@ -946,6 +946,95 @@
       ],
       "title": "Average Query Duration (Overall)",
       "type": "stat"
+    },
+    {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "${DS_PROMETHEUS}"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "palette-classic"
+          },
+          "custom": {
+            "axisBorderShow": false,
+            "axisCenteredZero": false,
+            "axisColorMode": "text",
+            "axisLabel": "",
+            "axisPlacement": "auto",
+            "fillOpacity": 80,
+            "gradientMode": "none",
+            "hideFrom": {
+              "legend": false,
+              "tooltip": false,
+              "viz": false
+            },
+            "lineWidth": 1,
+            "scaleDistribution": {
+              "type": "linear"
+            },
+            "thresholdsStyle": {
+              "mode": "off"
+            }
+          },
+          "mappings": [],
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 24,
+        "x": 0,
+        "y": 39
+      },
+      "id": 15,
+      "options": {
+        "barRadius": 0,
+        "barWidth": 0.97,
+        "fullHighlight": false,
+        "groupWidth": 0.7,
+        "legend": {
+          "calcs": [],
+          "displayMode": "list",
+          "placement": "bottom",
+          "showLegend": true
+        },
+        "orientation": "horizontal",
+        "showValue": "auto",
+        "stacking": "none",
+        "tooltip": {
+          "mode": "single",
+          "sort": "none"
+        },
+        "xTickLabelRotation": 0,
+        "xTickLabelSpacing": 0
+      },
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "${DS_PROMETHEUS}"
+          },
+          "editorMode": "code",
+          "expr": "sum(wordpress_db_query_duration_seconds_bucket) by (le)",
+          "format": "table",
+          "instant": true,
+          "legendFormat": "{{le}}",
+          "refId": "A"
+        }
+      ],
+      "title": "Query Duration Distribution (Buckets)",
+      "type": "barchart"
     }
   ],
   "refresh": "30s",

languages/wp-prometheus-de_CH.po

@@ -317,6 +317,10 @@ msgstr "HTTP-Anfragedauer-Verteilung"
 msgid "Database queries by endpoint"
 msgstr "Datenbank-Abfragen nach Endpunkt"
 
+#: src/Admin/Settings.php
+msgid "Database query duration distribution (requires SAVEQUERIES)"
+msgstr "Datenbank-Abfragedauer-Verteilung (erfordert SAVEQUERIES)"
+
 #: src/Admin/Settings.php
 msgid "Scheduled cron events by hook"
 msgstr "Geplante Cron-Ereignisse nach Hook"
@@ -947,3 +951,49 @@ msgstr "Laufzeit-Metriken erfassen HTTP-Anfragen und Datenbank-Abfragen ueber me
 #: src/Admin/Settings.php
 msgid "Reset Data"
 msgstr "Daten zuruecksetzen"
+
+#: src/Admin/Settings.php
+msgid "Extension"
+msgstr "Erweiterung"
+
+#. translators: %s: Plugin name
+#: src/Admin/Settings.php
+msgid "Provided by: %s"
+msgstr "Bereitgestellt von: %s"
+
+#: src/Admin/Settings.php
+msgid "No dashboards available."
+msgstr "Keine Dashboards verfuegbar."
+
+#: src/Admin/Settings.php
+msgid "Pre-built dashboards for visualizing your WordPress metrics in Grafana."
+msgstr "Vorgefertigte Dashboards zur Visualisierung Ihrer WordPress-Metriken in Grafana."
+
+#: src/Admin/Settings.php
+msgid "Installation Instructions"
+msgstr "Installationsanleitung"
+
+#: src/Admin/Settings.php
+msgid "Download the JSON file for your desired dashboard."
+msgstr "Laden Sie die JSON-Datei fuer das gewuenschte Dashboard herunter."
+
+#: src/Admin/Settings.php
+msgid "In Grafana, go to Dashboards → Import."
+msgstr "Gehen Sie in Grafana zu Dashboards → Import."
+
+#: src/Admin/Settings.php
+msgid "Upload the JSON file or paste its contents."
+msgstr "Laden Sie die JSON-Datei hoch oder fuegen Sie den Inhalt ein."
+
+#: src/Admin/Settings.php
+msgid "Select your Prometheus data source when prompted."
+msgstr "Waehlen Sie Ihre Prometheus-Datenquelle, wenn Sie dazu aufgefordert werden."
+
+#: src/Admin/Settings.php
+msgid "Click Import to create the dashboard."
+msgstr "Klicken Sie auf Import, um das Dashboard zu erstellen."
+
+#. translators: %s: Metrics URL
+#: src/Admin/Settings.php
+msgid "Make sure your Prometheus instance is configured to scrape %s with the correct authentication token."
+msgstr "Stellen Sie sicher, dass Ihre Prometheus-Instanz so konfiguriert ist, dass sie %s mit dem richtigen Authentifizierungs-Token abruft."

languages/wp-prometheus.pot

@@ -314,6 +314,10 @@ msgstr ""
 msgid "Database queries by endpoint"
 msgstr ""
 
+#: src/Admin/Settings.php
+msgid "Database query duration distribution (requires SAVEQUERIES)"
+msgstr ""
+
 #: src/Admin/Settings.php
 msgid "Scheduled cron events by hook"
 msgstr ""
@@ -944,3 +948,49 @@ msgstr ""
 #: src/Admin/Settings.php
 msgid "Reset Data"
 msgstr ""
+
+#: src/Admin/Settings.php
+msgid "Extension"
+msgstr ""
+
+#. translators: %s: Plugin name
+#: src/Admin/Settings.php
+msgid "Provided by: %s"
+msgstr ""
+
+#: src/Admin/Settings.php
+msgid "No dashboards available."
+msgstr ""
+
+#: src/Admin/Settings.php
+msgid "Pre-built dashboards for visualizing your WordPress metrics in Grafana."
+msgstr ""
+
+#: src/Admin/Settings.php
+msgid "Installation Instructions"
+msgstr ""
+
+#: src/Admin/Settings.php
+msgid "Download the JSON file for your desired dashboard."
+msgstr ""
+
+#: src/Admin/Settings.php
+msgid "In Grafana, go to Dashboards → Import."
+msgstr ""
+
+#: src/Admin/Settings.php
+msgid "Upload the JSON file or paste its contents."
+msgstr ""
+
+#: src/Admin/Settings.php
+msgid "Select your Prometheus data source when prompted."
+msgstr ""
+
+#: src/Admin/Settings.php
+msgid "Click Import to create the dashboard."
+msgstr ""
+
+#. translators: %s: Metrics URL
+#: src/Admin/Settings.php
+msgid "Make sure your Prometheus instance is configured to scrape %s with the correct authentication token."
+msgstr ""

src/Admin/DashboardProvider.php

@@ -16,22 +16,37 @@ if ( ! defined( 'ABSPATH' ) ) {
  * DashboardProvider class.
  *
  * Provides Grafana dashboard templates for download.
+ * Supports both built-in dashboards and third-party registrations.
  */
 class DashboardProvider {
 
 	/**
-	 * Dashboard directory path.
+	 * Dashboard directory path for built-in dashboards.
 	 *
 	 * @var string
 	 */
 	private string $dashboard_dir;
 
 	/**
-	 * Available dashboard definitions.
+	 * Built-in dashboard definitions.
 	 *
 	 * @var array
 	 */
-	private array $dashboards = array();
+	private array $builtin_dashboards = array();
+
+	/**
+	 * Third-party registered dashboard definitions.
+	 *
+	 * @var array
+	 */
+	private array $registered_dashboards = array();
+
+	/**
+	 * Whether the registration hook has been fired.
+	 *
+	 * @var bool
+	 */
+	private bool $hook_fired = false;
 
 	/**
 	 * Constructor.
@@ -39,43 +54,241 @@ class DashboardProvider {
 	public function __construct() {
 		$this->dashboard_dir = WP_PROMETHEUS_PATH . 'assets/dashboards/';
 
-		$this->dashboards = array(
+		$this->builtin_dashboards = array(
 			'wordpress-overview'    => array(
 				'title'       => __( 'WordPress Overview', 'wp-prometheus' ),
 				'description' => __( 'General WordPress metrics including users, posts, comments, and plugins.', 'wp-prometheus' ),
 				'file'        => 'wordpress-overview.json',
 				'icon'        => 'dashicons-wordpress',
+				'source'      => 'builtin',
 			),
 			'wordpress-runtime'     => array(
 				'title'       => __( 'Runtime Performance', 'wp-prometheus' ),
 				'description' => __( 'HTTP request metrics, database query performance, and response times.', 'wp-prometheus' ),
 				'file'        => 'wordpress-runtime.json',
 				'icon'        => 'dashicons-performance',
+				'source'      => 'builtin',
 			),
 			'wordpress-woocommerce' => array(
 				'title'       => __( 'WooCommerce Store', 'wp-prometheus' ),
 				'description' => __( 'WooCommerce metrics including products, orders, revenue, and customers.', 'wp-prometheus' ),
 				'file'        => 'wordpress-woocommerce.json',
 				'icon'        => 'dashicons-cart',
+				'source'      => 'builtin',
 			),
 		);
 	}
 
+	/**
+	 * Register a third-party dashboard.
+	 *
+	 * @param string $slug Dashboard slug (unique identifier).
+	 * @param array  $args Dashboard configuration {
+	 *     @type string $title       Dashboard title (required).
+	 *     @type string $description Dashboard description.
+	 *     @type string $icon        Dashicon class (e.g., 'dashicons-chart-bar').
+	 *     @type string $file        Absolute path to JSON file (mutually exclusive with 'json').
+	 *     @type string $json        Inline JSON content (mutually exclusive with 'file').
+	 *     @type string $plugin      Plugin name for attribution.
+	 * }
+	 * @return bool True if registered successfully, false otherwise.
+	 */
+	public function register_dashboard( string $slug, array $args ): bool {
+		// Sanitize slug - must be valid identifier.
+		$slug = sanitize_key( $slug );
+
+		if ( empty( $slug ) ) {
+			if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
+				// phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_error_log
+				error_log( 'WP Prometheus: Dashboard registration failed - invalid slug' );
+			}
+			return false;
+		}
+
+		// Check for duplicate slugs (built-in takes precedence).
+		if ( isset( $this->builtin_dashboards[ $slug ] ) ) {
+			if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
+				// phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_error_log
+				error_log( "WP Prometheus: Dashboard slug '$slug' conflicts with built-in dashboard" );
+			}
+			return false;
+		}
+
+		// Check for duplicate slugs in already registered dashboards.
+		if ( isset( $this->registered_dashboards[ $slug ] ) ) {
+			if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
+				// phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_error_log
+				error_log( "WP Prometheus: Dashboard slug '$slug' already registered" );
+			}
+			return false;
+		}
+
+		// Validate required fields.
+		if ( empty( $args['title'] ) ) {
+			if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
+				// phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_error_log
+				error_log( "WP Prometheus: Dashboard '$slug' missing required 'title'" );
+			}
+			return false;
+		}
+
+		// Must have either 'file' or 'json', not both.
+		$has_file = ! empty( $args['file'] );
+		$has_json = ! empty( $args['json'] );
+
+		if ( ! $has_file && ! $has_json ) {
+			if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
+				// phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_error_log
+				error_log( "WP Prometheus: Dashboard '$slug' must have 'file' or 'json'" );
+			}
+			return false;
+		}
+
+		if ( $has_file && $has_json ) {
+			if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
+				// phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_error_log
+				error_log( "WP Prometheus: Dashboard '$slug' cannot have both 'file' and 'json'" );
+			}
+			return false;
+		}
+
+		// Validate file path if provided.
+		if ( $has_file ) {
+			$file_path = $args['file'];
+
+			// Must be absolute path.
+			if ( ! path_is_absolute( $file_path ) ) {
+				if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
+					// phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_error_log
+					error_log( "WP Prometheus: Dashboard '$slug' file path must be absolute" );
+				}
+				return false;
+			}
+
+			// File must exist and be readable.
+			if ( ! file_exists( $file_path ) || ! is_readable( $file_path ) ) {
+				if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
+					// phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_error_log
+					error_log( "WP Prometheus: Dashboard '$slug' file not found: $file_path" );
+				}
+				return false;
+			}
+
+			// Security: Prevent path traversal - file must be under wp-content.
+			$real_path      = realpath( $file_path );
+			$wp_content_dir = realpath( WP_CONTENT_DIR );
+
+			if ( false === $real_path || false === $wp_content_dir ||
+				strpos( $real_path, $wp_content_dir ) !== 0 ) {
+				if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
+					// phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_error_log
+					error_log( "WP Prometheus: Dashboard '$slug' file outside wp-content" );
+				}
+				return false;
+			}
+		}
+
+		// Validate JSON if provided inline.
+		if ( $has_json ) {
+			$decoded = json_decode( $args['json'], true );
+			if ( null === $decoded && json_last_error() !== JSON_ERROR_NONE ) {
+				if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
+					// phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_error_log
+					error_log( "WP Prometheus: Dashboard '$slug' has invalid JSON" );
+				}
+				return false;
+			}
+		}
+
+		// Build dashboard entry.
+		$this->registered_dashboards[ $slug ] = array(
+			'title'       => sanitize_text_field( $args['title'] ),
+			'description' => sanitize_text_field( $args['description'] ?? '' ),
+			'icon'        => sanitize_html_class( $args['icon'] ?? 'dashicons-chart-line' ),
+			'file'        => $has_file ? $file_path : null,
+			'json'        => $has_json ? $args['json'] : null,
+			'plugin'      => sanitize_text_field( $args['plugin'] ?? '' ),
+			'source'      => 'third-party',
+		);
+
+		return true;
+	}
+
+	/**
+	 * Fire the dashboard registration hook with protection.
+	 *
+	 * @return void
+	 */
+	private function fire_registration_hook(): void {
+		if ( $this->hook_fired ) {
+			return;
+		}
+
+		$this->hook_fired = true;
+
+		// Check for isolated mode - skip third-party hooks.
+		$isolated_mode = defined( 'WP_PROMETHEUS_ISOLATED_MODE' ) && WP_PROMETHEUS_ISOLATED_MODE;
+
+		// Also check option for admin-side isolated mode.
+		if ( ! $isolated_mode ) {
+			$isolated_mode = (bool) get_option( 'wp_prometheus_isolated_mode', false );
+		}
+
+		if ( $isolated_mode ) {
+			return;
+		}
+
+		// Use output buffering to capture any accidental output.
+		ob_start();
+
+		try {
+			/**
+			 * Fires to allow third-party plugins to register dashboards.
+			 *
+			 * @since 0.4.6
+			 *
+			 * @param DashboardProvider $provider The dashboard provider instance.
+			 */
+			do_action( 'wp_prometheus_register_dashboards', $this );
+		} catch ( \Throwable $e ) {
+			if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
+				// phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_error_log
+				error_log( 'WP Prometheus: Error in dashboard registration hook: ' . $e->getMessage() );
+			}
+		}
+
+		// Discard any output from plugins.
+		ob_end_clean();
+	}
+
 	/**
 	 * Get list of available dashboards.
 	 *
 	 * @return array
 	 */
 	public function get_available(): array {
+		// Fire registration hook first (only once).
+		$this->fire_registration_hook();
+
 		$available = array();
 
-		foreach ( $this->dashboards as $slug => $dashboard ) {
+		// Add built-in dashboards (check file exists).
+		foreach ( $this->builtin_dashboards as $slug => $dashboard ) {
 			$file_path = $this->dashboard_dir . $dashboard['file'];
 			if ( file_exists( $file_path ) ) {
 				$available[ $slug ] = $dashboard;
 			}
 		}
 
+		// Add registered third-party dashboards.
+		foreach ( $this->registered_dashboards as $slug => $dashboard ) {
+			// Already validated during registration, but double-check.
+			if ( ! empty( $dashboard['json'] ) ||
+				( ! empty( $dashboard['file'] ) && file_exists( $dashboard['file'] ) ) ) {
+				$available[ $slug ] = $dashboard;
+			}
+		}
+
 		return $available;
 	}
 
@@ -86,20 +299,23 @@ class DashboardProvider {
 	 * @return string|null JSON content or null if not found.
 	 */
 	public function get_dashboard( string $slug ): ?string {
-		// Validate slug to prevent directory traversal.
+		// Fire registration hook first.
+		$this->fire_registration_hook();
+
+		// Validate slug.
 		$slug = sanitize_file_name( $slug );
 
-		if ( ! isset( $this->dashboards[ $slug ] ) ) {
+		// Check built-in dashboards first.
-			return null;
+		if ( isset( $this->builtin_dashboards[ $slug ] ) ) {
-		}
+			$dashboard = $this->builtin_dashboards[ $slug ];
-
+			$file_path = $this->dashboard_dir . $dashboard['file'];
-		$file_path = $this->dashboard_dir . $this->dashboards[ $slug ]['file'];
 
 			// Security: Ensure file is within dashboard directory.
 			$real_path = realpath( $file_path );
 			$real_dir  = realpath( $this->dashboard_dir );
 
-		if ( false === $real_path || false === $real_dir || strpos( $real_path, $real_dir ) !== 0 ) {
+			if ( false === $real_path || false === $real_dir ||
+				strpos( $real_path, $real_dir ) !== 0 ) {
 				return null;
 			}
 
@@ -110,11 +326,43 @@ class DashboardProvider {
 			// phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents
 			$content = file_get_contents( $file_path );
 
-		if ( false === $content ) {
+			return false === $content ? null : $content;
+		}
+
+		// Check registered dashboards.
+		if ( isset( $this->registered_dashboards[ $slug ] ) ) {
+			$dashboard = $this->registered_dashboards[ $slug ];
+
+			// Inline JSON.
+			if ( ! empty( $dashboard['json'] ) ) {
+				return $dashboard['json'];
+			}
+
+			// File-based.
+			if ( ! empty( $dashboard['file'] ) ) {
+				$file_path = $dashboard['file'];
+
+				// Security: Re-verify file is under wp-content.
+				$real_path      = realpath( $file_path );
+				$wp_content_dir = realpath( WP_CONTENT_DIR );
+
+				if ( false === $real_path || false === $wp_content_dir ||
+					strpos( $real_path, $wp_content_dir ) !== 0 ) {
 					return null;
 				}
 
-		return $content;
+				if ( ! file_exists( $file_path ) || ! is_readable( $file_path ) ) {
+					return null;
+				}
+
+				// phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents
+				$content = file_get_contents( $file_path );
+
+				return false === $content ? null : $content;
+			}
+		}
+
+		return null;
 	}
 
 	/**
@@ -124,13 +372,20 @@ class DashboardProvider {
 	 * @return array|null Dashboard metadata or null if not found.
 	 */
 	public function get_metadata( string $slug ): ?array {
+		// Fire registration hook first.
+		$this->fire_registration_hook();
+
 		$slug = sanitize_file_name( $slug );
 
-		if ( ! isset( $this->dashboards[ $slug ] ) ) {
+		if ( isset( $this->builtin_dashboards[ $slug ] ) ) {
-			return null;
+			return $this->builtin_dashboards[ $slug ];
 		}
 
-		return $this->dashboards[ $slug ];
+		if ( isset( $this->registered_dashboards[ $slug ] ) ) {
+			return $this->registered_dashboards[ $slug ];
+		}
+
+		return null;
 	}
 
 	/**
@@ -140,12 +395,61 @@ class DashboardProvider {
 	 * @return string|null Filename or null if not found.
 	 */
 	public function get_filename( string $slug ): ?string {
+		// Fire registration hook first.
+		$this->fire_registration_hook();
+
 		$slug = sanitize_file_name( $slug );
 
-		if ( ! isset( $this->dashboards[ $slug ] ) ) {
+		// Built-in dashboards have predefined filenames.
+		if ( isset( $this->builtin_dashboards[ $slug ] ) ) {
+			return $this->builtin_dashboards[ $slug ]['file'];
+		}
+
+		// Registered dashboards - use file basename or generate from slug.
+		if ( isset( $this->registered_dashboards[ $slug ] ) ) {
+			$dashboard = $this->registered_dashboards[ $slug ];
+
+			if ( ! empty( $dashboard['file'] ) ) {
+				return basename( $dashboard['file'] );
+			}
+
+			// Generate filename from slug for inline JSON.
+			return $slug . '.json';
+		}
+
 		return null;
 	}
 
-		return $this->dashboards[ $slug ]['file'];
+	/**
+	 * Check if a dashboard is from a third-party plugin.
+	 *
+	 * @param string $slug Dashboard slug.
+	 * @return bool True if third-party, false if built-in or not found.
+	 */
+	public function is_third_party( string $slug ): bool {
+		$this->fire_registration_hook();
+
+		$slug = sanitize_file_name( $slug );
+
+		return isset( $this->registered_dashboards[ $slug ] );
+	}
+
+	/**
+	 * Get the plugin name for a third-party dashboard.
+	 *
+	 * @param string $slug Dashboard slug.
+	 * @return string|null Plugin name or null if not found/built-in.
+	 */
+	public function get_plugin_name( string $slug ): ?string {
+		$this->fire_registration_hook();
+
+		$slug = sanitize_file_name( $slug );
+
+		if ( isset( $this->registered_dashboards[ $slug ] ) ) {
+			$plugin = $this->registered_dashboards[ $slug ]['plugin'];
+			return ! empty( $plugin ) ? $plugin : null;
+		}
+
+		return null;
 	}
 }

src/Admin/Settings.php

@@ -1214,20 +1214,45 @@ class Settings {
 			<h2><?php esc_html_e( 'Grafana Dashboard Templates', 'wp-prometheus' ); ?></h2>
 			<p class="description"><?php esc_html_e( 'Pre-built dashboards for visualizing your WordPress metrics in Grafana.', 'wp-prometheus' ); ?></p>
 
+			<?php if ( empty( $dashboards ) ) : ?>
+				<p class="description"><?php esc_html_e( 'No dashboards available.', 'wp-prometheus' ); ?></p>
+			<?php else : ?>
 				<div class="wp-prometheus-dashboard-grid">
-				<?php foreach ( $dashboards as $slug => $dashboard ) : ?>
+					<?php
-					<div class="wp-prometheus-dashboard-card">
+					foreach ( $dashboards as $slug => $dashboard ) :
+						$is_third_party = $this->dashboard_provider->is_third_party( $slug );
+						$plugin_name    = $this->dashboard_provider->get_plugin_name( $slug );
+						$card_class     = 'wp-prometheus-dashboard-card' . ( $is_third_party ? ' third-party' : '' );
+						?>
+						<div class="<?php echo esc_attr( $card_class ); ?>">
+							<?php if ( $is_third_party ) : ?>
+								<span class="dashboard-badge"><?php esc_html_e( 'Extension', 'wp-prometheus' ); ?></span>
+							<?php endif; ?>
 							<div class="dashboard-icon">
 								<span class="dashicons <?php echo esc_attr( $dashboard['icon'] ); ?>"></span>
 							</div>
 							<h3><?php echo esc_html( $dashboard['title'] ); ?></h3>
 							<p><?php echo esc_html( $dashboard['description'] ); ?></p>
+							<?php if ( $is_third_party && $plugin_name ) : ?>
+								<p class="dashboard-plugin">
+									<small>
+										<?php
+										printf(
+											/* translators: %s: Plugin name */
+											esc_html__( 'Provided by: %s', 'wp-prometheus' ),
+											esc_html( $plugin_name )
+										);
+										?>
+									</small>
+								</p>
+							<?php endif; ?>
 							<button type="button" class="button button-primary download-dashboard" data-slug="<?php echo esc_attr( $slug ); ?>">
 								<?php esc_html_e( 'Download', 'wp-prometheus' ); ?>
 							</button>
 						</div>
 					<?php endforeach; ?>
 				</div>
+			<?php endif; ?>
 
 			<hr style="margin: 30px 0;">
 
@@ -1340,6 +1365,11 @@ class Settings {
 					<td><?php esc_html_e( 'Counter', 'wp-prometheus' ); ?></td>
 					<td><?php esc_html_e( 'Database queries by endpoint', 'wp-prometheus' ); ?></td>
 				</tr>
+				<tr>
+					<td><code>wordpress_db_query_duration_seconds</code></td>
+					<td><?php esc_html_e( 'Histogram', 'wp-prometheus' ); ?></td>
+					<td><?php esc_html_e( 'Database query duration distribution (requires SAVEQUERIES)', 'wp-prometheus' ); ?></td>
+				</tr>
 				<tr>
 					<td><code>wordpress_cron_events_total</code></td>
 					<td><?php esc_html_e( 'Gauge', 'wp-prometheus' ); ?></td>

wp-prometheus.php

@@ -3,7 +3,7 @@
  * Plugin Name: WP Prometheus
  * Plugin URI: https://src.bundespruefstelle.ch/magdev/wp-prometheus
  * Description: Prometheus metrics endpoint for WordPress with extensible hooks for custom metrics.
- * Version: 0.4.5
+ * Version: 0.4.7
  * Requires at least: 6.4
  * Requires PHP: 8.3
  * Author: Marco Graetsch
@@ -169,7 +169,7 @@ wp_prometheus_early_metrics_check();
  *
  * @var string
  */
-define( 'WP_PROMETHEUS_VERSION', '0.4.5' );
+define( 'WP_PROMETHEUS_VERSION', '0.4.7' );
 
 /**
  * Plugin file path.