[Lens as code] Fix metric trendline

src/platform/packages/shared/kbn-lens-embeddable-utils/config_builder/transforms/charts/metric.ts

@@ -42,6 +42,7 @@ import {
   operationFromColumn,
 } from '../utils';
 import { fromBucketLensApiToLensState } from '../columns/buckets';
+import { getHistogramColumn } from '../../columns/date_histogram';
 import { getValueApiColumn, getValueColumn } from '../columns/esql_column';
 import type { MetricConfig } from '../../schema';
 import { fromMetricAPItoLensState } from '../columns/metric';
@@ -577,8 +578,9 @@ function buildFormBasedLayer(layer: MetricConfigNoESQL): FormBasedPersistedState
 
   addLayerColumn(defaultLayer, getAccessorName('metric'), newPrimaryColumns);
   if (trendLineLayer) {
+    // Histogram first so columnOrder matches editor-built trendline layers and tabify agg order.
+    addLayerColumn(trendLineLayer, HISTOGRAM_COLUMN_NAME, getHistogramColumn({}));
     addLayerColumn(trendLineLayer, `${ACCESSOR}_trendline`, newPrimaryColumns);
-    addLayerColumn(trendLineLayer, HISTOGRAM_COLUMN_NAME, newPrimaryColumns);
   }
 
   if (layer.breakdown_by) {
@@ -661,11 +663,15 @@ export function fromAPItoLensState(config: MetricConfig): MetricAttributesWithou
   const visualization = buildVisualizationState(config);
 
   const { adHocDataViews, internalReferences } = getAdhocDataviews(usedDataviews);
-  const regularDataViews = Object.values(usedDataviews).filter(
-    (v): v is { id: string; type: 'dataView' } => v.type === 'dataView'
-  );
-  const references = regularDataViews.length
-    ? buildReferences({ [DEFAULT_LAYER_ID]: regularDataViews[0]?.id })
+
+  const regularDataViewsByLayer: Record<string, string> = {};
+  for (const [layerId, dv] of Object.entries(usedDataviews)) {
+    if (dv.type === 'dataView') {
+      regularDataViewsByLayer[layerId] = dv.id;
+    }
+  }
+  const references = Object.keys(regularDataViewsByLayer).length
+    ? buildReferences(regularDataViewsByLayer)
     : [];
 
   return {

x-pack/platform/plugins/shared/lens/test/scout/ui/parallel_tests/metric_trendline.spec.ts

@@ -0,0 +1,162 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import { spaceTest, tags } from '@kbn/scout';
+import { expect } from '@kbn/scout/ui';
+import type { KbnClient } from '@kbn/scout';
+import { testData } from '../fixtures';
+
+const DASHBOARD_API_PATH = '/api/dashboards';
+const DASHBOARD_API_VERSION = '2023-10-31';
+
+const LOGSTASH_TIME_RANGE = {
+  from: '2015-09-19T06:31:44.000Z',
+  to: '2015-09-23T18:31:44.000Z',
+};
+
+function withSpace(path: string, spaceId: string): string {
+  return `/s/${spaceId}${path}`;
+}
+
+async function createDashboard(client: KbnClient, body: unknown, spaceId: string): Promise<string> {
+  const response = await client.request<unknown>({
+    method: 'POST',
+    path: withSpace(DASHBOARD_API_PATH, spaceId),
+    body,
+    headers: { 'elastic-api-version': DASHBOARD_API_VERSION },
+  });
+
+  if (response.status !== 201) {
+    throw new Error(
+      `Expected dashboard create status 201, got ${response.status}: ${JSON.stringify(
+        response.data
+      )}`
+    );
+  }
+
+  const { id } = response.data as Record<string, unknown>;
+  if (typeof id !== 'string' || id.length === 0) {
+    throw new Error('Dashboard create response: expected a non-empty string id');
+  }
+  return id;
+}
+
+spaceTest.describe(
+  'Lens metric trendline on dashboard (DSL)',
+  { tag: tags.stateful.classic },
+  () => {
+    let storedDataViewId: string | undefined;
+
+    spaceTest.beforeAll(async ({ scoutSpace, apiServices }) => {
+      await scoutSpace.uiSettings.set({
+        defaultIndex: testData.DATA_VIEW_ID.LOGSTASH,
+        'dateFormat:tz': 'UTC',
+        'timepicker:timeDefaults': JSON.stringify({
+          from: testData.LOGSTASH_IN_RANGE_DATES.from,
+          to: testData.LOGSTASH_IN_RANGE_DATES.to,
+        }),
+      });
+
+      const { data: dataView } = await apiServices.dataViews.create({
+        title: testData.DATA_VIEW_ID.LOGSTASH,
+        name: `scout-metric-trendline-dv-${Date.now()}`,
+        timeFieldName: '@timestamp',
+        spaceId: scoutSpace.id,
+      });
+      storedDataViewId = dataView.id;
+    });
+
+    spaceTest.afterAll(async ({ scoutSpace, apiServices }) => {
+      if (storedDataViewId) {
+        await apiServices.dataViews.delete(storedDataViewId, scoutSpace.id);
+      }
+      await scoutSpace.uiSettings.unset('defaultIndex', 'dateFormat:tz', 'timepicker:timeDefaults');
+      await scoutSpace.savedObjects.cleanStandardList();
+    });
+
+    spaceTest(
+      'renders trendline when panel uses inline data view spec',
+      async ({ browserAuth, kbnClient, page, pageObjects, scoutSpace }) => {
+        const body = {
+          title: 'Metric trendline spec',
+          time_range: LOGSTASH_TIME_RANGE,
+          panels: [
+            {
+              type: 'vis',
+              grid: { x: 0, y: 0, w: 12, h: 8 },
+              config: {
+                type: 'metric',
+                title: 'Average bytes with trend',
+                data_source: {
+                  type: 'data_view_spec',
+                  index_pattern: testData.DATA_VIEW_ID.LOGSTASH,
+                  time_field: '@timestamp',
+                },
+                metrics: [
+                  {
+                    type: 'primary',
+                    operation: 'average',
+                    field: 'bytes',
+                    background_chart: { type: 'trend' },
+                  },
+                ],
+              },
+            },
+          ],
+        };
+
+        const dashboardId = await createDashboard(kbnClient, body, scoutSpace.id);
+        await browserAuth.loginAsPrivilegedUser();
+        await pageObjects.dashboard.openDashboardWithId(dashboardId);
+
+        await expect(page.getByTestId('mtrVis')).toBeVisible();
+        await expect(page.locator('.echSingleMetricSparkline')).toBeVisible();
+      }
+    );
+
+    spaceTest(
+      'renders trendline when panel uses stored data view reference',
+      async ({ browserAuth, kbnClient, page, pageObjects, scoutSpace }) => {
+        spaceTest.fail(!storedDataViewId, 'Stored data view was not created in beforeAll');
+
+        const body = {
+          title: 'Metric trendline ref',
+          time_range: LOGSTASH_TIME_RANGE,
+          panels: [
+            {
+              type: 'vis',
+              grid: { x: 0, y: 0, w: 12, h: 8 },
+              config: {
+                type: 'metric',
+                title: 'Average bytes with trend',
+                data_source: {
+                  type: 'data_view_reference',
+                  ref_id: storedDataViewId!,
+                },
+                metrics: [
+                  {
+                    type: 'primary',
+                    operation: 'average',
+                    field: 'bytes',
+                    background_chart: { type: 'trend' },
+                  },
+                ],
+              },
+            },
+          ],
+        };
+
+        const dashboardId = await createDashboard(kbnClient, body, scoutSpace.id);
+        await browserAuth.loginAsPrivilegedUser();
+        await pageObjects.dashboard.openDashboardWithId(dashboardId);
+
+        await expect(page.getByTestId('mtrVis')).toBeVisible();
+        await expect(page.locator('.echSingleMetricSparkline')).toBeVisible();
+      }
+    );
+  }
+);