From b1b0af06e71b45833148eb0b6c3c64f59621cb18 Mon Sep 17 00:00:00 2001
From: Joey <joey.tawadrous@grafana.com>
Date: Tue, 2 Dec 2025 09:40:36 +0000
Subject: [PATCH] Add Metrics Drilldown

---
 .../ExploreMapMetricsDrilldownPanel.tsx       | 150 ++++++++++++++++++
 .../ExploreMapTracesDrilldownPanel.tsx        |   4 +-
 .../components/ExploreMapFloatingToolbar.tsx  |  18 +++
 .../components/ExploreMapPanelContent.tsx     |  11 +-
 public/app/features/explore-map/crdt/state.ts |   2 +-
 public/app/features/explore-map/crdt/types.ts |   8 +-
 .../features/explore-map/state/crdtSlice.ts   |  11 +-
 .../app/features/explore-map/state/types.ts   |   3 +-
 8 files changed, 191 insertions(+), 16 deletions(-)
 create mode 100644 public/app/features/explore-map/components/Drilldown/ExploreMapMetricsDrilldownPanel.tsx
 rename public/app/features/explore-map/components/{ => Drilldown}/ExploreMapTracesDrilldownPanel.tsx (97%)

diff --git a/public/app/features/explore-map/components/Drilldown/ExploreMapMetricsDrilldownPanel.tsx b/public/app/features/explore-map/components/Drilldown/ExploreMapMetricsDrilldownPanel.tsx
new file mode 100644
index 00000000000..028523e37a3
--- /dev/null
+++ b/public/app/features/explore-map/components/Drilldown/ExploreMapMetricsDrilldownPanel.tsx
@@ -0,0 +1,150 @@
+import { css } from '@emotion/css';
+import { useEffect, useRef, useState } from 'react';
+
+import { GrafanaTheme2 } from '@grafana/data';
+import { Trans, t } from '@grafana/i18n';
+import { config } from '@grafana/runtime';
+import { useStyles2 } from '@grafana/ui';
+import { useDispatch, useSelector } from 'app/types/store';
+
+import { updatePanelIframeUrl } from '../../state/crdtSlice';
+import { selectPanels } from '../../state/selectors';
+
+interface ExploreMapMetricsDrilldownPanelProps {
+  exploreId: string;
+  width: number;
+  height: number;
+}
+
+export function ExploreMapMetricsDrilldownPanel({ exploreId, width, height }: ExploreMapMetricsDrilldownPanelProps) {
+  const styles = useStyles2(getStyles);
+  const dispatch = useDispatch();
+  const [isInitialized, setIsInitialized] = useState(false);
+  const iframeRef = useRef<HTMLIFrameElement>(null);
+
+  // Find the panel with this exploreId to get saved state
+  const panel = useSelector((state) => {
+    const panels = selectPanels(state.exploreMapCRDT);
+    return Object.values(panels).find((p) => p.exploreId === exploreId);
+  });
+
+  // Build iframe URL for metrics drilldown - use saved URL if available, otherwise default
+  // IMPORTANT: Only compute this once on mount to prevent iframe reloads
+  const [metricsDrilldownUrl] = useState(() => {
+    // If we have a saved iframe URL from previous session, use it
+    if (panel?.mode === 'metrics-drilldown' && panel?.iframeUrl) {
+      return panel.iframeUrl;
+    }
+    // Otherwise, construct the default URL
+    const origin = window.location.origin;
+    const subUrl = config.appSubUrl || '';
+    const appPath = '/a/grafana-metricsdrilldown-app';
+    return `${origin}${subUrl}${appPath}`;
+  });
+
+  // Initialize immediately for metrics drilldown panels
+  useEffect(() => {
+    setIsInitialized(true);
+  }, []);
+
+  // Auto-save iframe URL changes for metrics-drilldown panels
+  useEffect(() => {
+    if (!isInitialized) {
+      return;
+    }
+
+    const panelId = panel?.id;
+    if (!panelId) {
+      return;
+    }
+
+    let lastSavedUrl = panel?.iframeUrl || '';
+
+    const checkAndSaveUrl = () => {
+      const iframe = iframeRef.current;
+      if (!iframe) {
+        return;
+      }
+
+      try {
+        const currentUrl = iframe.contentWindow?.location.href;
+        if (currentUrl && currentUrl !== lastSavedUrl) {
+          lastSavedUrl = currentUrl;
+          dispatch(
+            updatePanelIframeUrl({
+              panelId,
+              iframeUrl: currentUrl,
+            })
+          );
+        } else if (!currentUrl) {
+          console.log('No URL detected');
+        }
+      } catch (e) {
+        console.error('Cannot read iframe URL:', e);
+      }
+    };
+
+    // Start checking periodically (every 2 seconds)
+    const intervalId = setInterval(checkAndSaveUrl, 2000);
+
+    // Also check immediately
+    setTimeout(checkAndSaveUrl, 100);
+
+    return () => {
+      clearInterval(intervalId);
+    };
+    // Intentionally not including panel.iframeUrl to avoid re-creating interval on every save
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [isInitialized, panel?.id, dispatch]);
+
+  if (!isInitialized) {
+    return (
+      <div className={styles.container}>
+        <div className={styles.loading}>
+          <Trans i18nKey="explore-map.panel.initializing">Initializing...</Trans>
+        </div>
+      </div>
+    );
+  }
+
+  return (
+    <div
+      className={styles.container}
+      style={{
+        width: `${width}px`,
+        height: `${height}px`,
+      }}
+    >
+      <iframe
+        ref={iframeRef}
+        src={metricsDrilldownUrl}
+        title={t('explore-map.panel.metrics-drilldown', 'Metrics Drilldown')}
+        style={{
+          width: '100%',
+          height: '100%',
+          border: 'none',
+        }}
+      />
+    </div>
+  );
+}
+
+const getStyles = (theme: GrafanaTheme2) => {
+  return {
+    container: css({
+      width: '100%',
+      height: '100%',
+      overflow: 'hidden',
+      position: 'relative',
+    }),
+    loading: css({
+      display: 'flex',
+      alignItems: 'center',
+      justifyContent: 'center',
+      height: '100%',
+      color: theme.colors.text.secondary,
+      fontSize: theme.typography.body.fontSize,
+    }),
+  };
+};
+
diff --git a/public/app/features/explore-map/components/ExploreMapTracesDrilldownPanel.tsx b/public/app/features/explore-map/components/Drilldown/ExploreMapTracesDrilldownPanel.tsx
similarity index 97%
rename from public/app/features/explore-map/components/ExploreMapTracesDrilldownPanel.tsx
rename to public/app/features/explore-map/components/Drilldown/ExploreMapTracesDrilldownPanel.tsx
index f6a34c00343..e39906f4e5f 100644
--- a/public/app/features/explore-map/components/ExploreMapTracesDrilldownPanel.tsx
+++ b/public/app/features/explore-map/components/Drilldown/ExploreMapTracesDrilldownPanel.tsx
@@ -7,8 +7,8 @@ import { config } from '@grafana/runtime';
 import { useStyles2 } from '@grafana/ui';
 import { useDispatch, useSelector } from 'app/types/store';
 
-import { updatePanelIframeUrl } from '../state/crdtSlice';
-import { selectPanels } from '../state/selectors';
+import { updatePanelIframeUrl } from '../../state/crdtSlice';
+import { selectPanels } from '../../state/selectors';
 
 interface ExploreMapTracesDrilldownPanelProps {
   exploreId: string;
diff --git a/public/app/features/explore-map/components/ExploreMapFloatingToolbar.tsx b/public/app/features/explore-map/components/ExploreMapFloatingToolbar.tsx
index d090ad0447f..84c80c21c82 100644
--- a/public/app/features/explore-map/components/ExploreMapFloatingToolbar.tsx
+++ b/public/app/features/explore-map/components/ExploreMapFloatingToolbar.tsx
@@ -38,6 +38,19 @@ export function ExploreMapFloatingToolbar() {
     setIsOpen(false);
   }, [dispatch]);
 
+  const handleAddMetricsDrilldownPanel = useCallback(() => {
+    dispatch(
+      addPanel({
+        viewportSize: {
+          width: window.innerWidth,
+          height: window.innerHeight,
+        },
+        kind: 'metrics-drilldown',
+      })
+    );
+    setIsOpen(false);
+  }, [dispatch]);
+
   const MenuActions = () => (
     <Menu>
       <MenuItem
@@ -50,6 +63,11 @@ export function ExploreMapFloatingToolbar() {
         icon="drilldown"
         onClick={handleAddTracesDrilldownPanel}
       />
+      <MenuItem
+        label={t('explore-map.toolbar.add-metrics-drilldown-panel', 'Add Metrics Drilldown panel')}
+        icon="chart-line"
+        onClick={handleAddMetricsDrilldownPanel}
+      />
     </Menu>
   );
 
diff --git a/public/app/features/explore-map/components/ExploreMapPanelContent.tsx b/public/app/features/explore-map/components/ExploreMapPanelContent.tsx
index 3d667033645..bc8a457fe4d 100644
--- a/public/app/features/explore-map/components/ExploreMapPanelContent.tsx
+++ b/public/app/features/explore-map/components/ExploreMapPanelContent.tsx
@@ -14,7 +14,8 @@ import { usePanelStateSync } from '../hooks/usePanelStateSync';
 // import { useExploreStateSync } from '../hooks/useExploreStateSync';
 import { selectPanels } from '../state/selectors';
 
-import { ExploreMapTracesDrilldownPanel } from './ExploreMapTracesDrilldownPanel';
+import { ExploreMapMetricsDrilldownPanel } from './Drilldown/ExploreMapMetricsDrilldownPanel';
+import { ExploreMapTracesDrilldownPanel } from './Drilldown/ExploreMapTracesDrilldownPanel';
 
 interface ExploreMapPanelContentProps {
   panelId: string;
@@ -122,8 +123,8 @@ export function ExploreMapPanelContent({ panelId, exploreId, width, height }: Ex
 
   // Initialize Explore pane on mount (only for standard Explore panels)
   useEffect(() => {
-    if (panel?.mode === 'traces-drilldown') {
-      // Traces drilldown panels don't need Explore initialization
+    if (panel?.mode === 'traces-drilldown' || panel?.mode === 'metrics-drilldown') {
+      // Drilldown panels don't need Explore initialization
       setIsInitialized(true);
       return;
     }
@@ -160,6 +161,10 @@ export function ExploreMapPanelContent({ panelId, exploreId, width, height }: Ex
     return <ExploreMapTracesDrilldownPanel exploreId={exploreId} width={width} height={height} />;
   }
 
+  if (panel?.mode === 'metrics-drilldown') {
+    return <ExploreMapMetricsDrilldownPanel exploreId={exploreId} width={width} height={height} />;
+  }
+
   // Wait for Redux state to be initialized
   if (!isInitialized) {
     return (
diff --git a/public/app/features/explore-map/crdt/state.ts b/public/app/features/explore-map/crdt/state.ts
index 8f475b1d0d0..4eb16edb61d 100644
--- a/public/app/features/explore-map/crdt/state.ts
+++ b/public/app/features/explore-map/crdt/state.ts
@@ -141,7 +141,7 @@ export class CRDTStateManager {
     panelId: string,
     exploreId: string,
     position: { x: number; y: number; width: number; height: number },
-    mode: 'explore' | 'traces-drilldown' = 'explore'
+    mode: 'explore' | 'traces-drilldown' | 'metrics-drilldown' = 'explore'
   ): AddPanelOperation {
     const timestamp = this.clock.tick();
     return {
diff --git a/public/app/features/explore-map/crdt/types.ts b/public/app/features/explore-map/crdt/types.ts
index 4ea3a037868..6a1199d415e 100644
--- a/public/app/features/explore-map/crdt/types.ts
+++ b/public/app/features/explore-map/crdt/types.ts
@@ -30,8 +30,8 @@ export interface CRDTPanelData {
   // CRDT-replicated explore state
   exploreState: LWWRegister<SerializedExploreState | undefined>;
 
-  // Panel mode (explore or traces-drilldown)
-  mode: LWWRegister<'explore' | 'traces-drilldown'>;
+  // Panel mode (explore, traces-drilldown, or metrics-drilldown)
+  mode: LWWRegister<'explore' | 'traces-drilldown' | 'metrics-drilldown'>;
 
   // Iframe URL for traces-drilldown panels
   iframeUrl: LWWRegister<string | undefined>;
@@ -98,7 +98,7 @@ export interface CRDTExploreMapStateJSON {
     height: { value: number; timestamp: HLCTimestamp };
     zIndex: { value: number; timestamp: HLCTimestamp };
     exploreState: { value: SerializedExploreState | undefined; timestamp: HLCTimestamp };
-    mode: { value: 'explore' | 'traces-drilldown'; timestamp: HLCTimestamp };
+    mode: { value: 'explore' | 'traces-drilldown' | 'metrics-drilldown'; timestamp: HLCTimestamp };
     iframeUrl: { value: string | undefined; timestamp: HLCTimestamp };
     remoteVersion?: number;
   }>;
@@ -147,7 +147,7 @@ export interface AddPanelOperation extends CRDTOperationBase {
       width: number;
       height: number;
     };
-    mode?: 'explore' | 'traces-drilldown';
+    mode?: 'explore' | 'traces-drilldown' | 'metrics-drilldown';
   };
 }
 
diff --git a/public/app/features/explore-map/state/crdtSlice.ts b/public/app/features/explore-map/state/crdtSlice.ts
index 308fa8b504e..98734c8e80d 100644
--- a/public/app/features/explore-map/state/crdtSlice.ts
+++ b/public/app/features/explore-map/state/crdtSlice.ts
@@ -202,7 +202,7 @@ const crdtSlice = createSlice({
     addPanel: (state, action: PayloadAction<{
       viewportSize?: { width: number; height: number };
       position?: { x: number; y: number; width: number; height: number };
-      kind?: 'explore' | 'traces-drilldown';
+      kind?: 'explore' | 'traces-drilldown' | 'metrics-drilldown';
     }>) => {
       const manager = getCRDTManager(state);
 
@@ -214,9 +214,10 @@ const crdtSlice = createSlice({
       const mode = action.payload.kind || 'explore';
       
       // Set default panel size based on panel type
-      // Traces drilldown panels are larger to accommodate the iframe content
-      const defaultWidth = mode === 'traces-drilldown' ? 1000 : 600;
-      const defaultHeight = mode === 'traces-drilldown' ? 550 : 400;
+      // Drilldown panels (traces and metrics) are larger to accommodate the iframe content
+      const isDrilldownPanel = mode === 'traces-drilldown' || mode === 'metrics-drilldown';
+      const defaultWidth = isDrilldownPanel ? 1000 : 600;
+      const defaultHeight = isDrilldownPanel ? 550 : 400;
       
       const panelWidth = action.payload.position?.width || defaultWidth;
       const panelHeight = action.payload.position?.height || defaultHeight;
@@ -467,7 +468,7 @@ const crdtSlice = createSlice({
           width: sourcePanel.position.width,
           height: sourcePanel.position.height,
         },
-        sourcePanel.mode || 'explore'
+        (sourcePanel.mode || 'explore') as 'explore' | 'traces-drilldown' | 'metrics-drilldown'
       );
 
       manager.applyOperation(addOperation);
diff --git a/public/app/features/explore-map/state/types.ts b/public/app/features/explore-map/state/types.ts
index 58a4cc211cb..37f36a01533 100644
--- a/public/app/features/explore-map/state/types.ts
+++ b/public/app/features/explore-map/state/types.ts
@@ -27,8 +27,9 @@ export interface ExploreMapPanel {
    * Panel mode determines what kind of content is rendered inside the panel.
    * - 'explore': standard Explore pane (current behavior)
    * - 'traces-drilldown': Traces Drilldown app
+   * - 'metrics-drilldown': Metrics Drilldown app
    */
-  mode: 'explore' | 'traces-drilldown';
+  mode: 'explore' | 'traces-drilldown' | 'metrics-drilldown';
   /**
    * For iframe-based panels (like traces-drilldown), store the complete URL
    * including query parameters to restore state on reload