properly detect histograms

public/app/features/dashboard-scene/edit-pane/promQueries.test.ts

@@ -0,0 +1,124 @@
+import { getQueriesForMetric, findMetadataForMetric } from './promQueries';
+
+describe('promQueries', () => {
+  const mockMetadata = {
+    'http_request_duration': {
+      type: 'histogram',
+      help: 'Duration of HTTP requests',
+    },
+    'http_request_duration_bucket': {
+      type: 'counter',
+      help: 'Cumulative counters for the observation buckets (Duration of HTTP requests)',
+    },
+    'http_request_duration_count': {
+      type: 'counter',
+      help: 'Count of events that have been observed for the histogram metric (Duration of HTTP requests)',
+    },
+    'http_request_duration_sum': {
+      type: 'counter',
+      help: 'Total sum of all observed values for the histogram metric (Duration of HTTP requests)',
+    },
+    'cpu_usage': {
+      type: 'gauge',
+      help: 'CPU usage percentage',
+    },
+    'requests_total': {
+      type: 'counter',
+      help: 'Total number of requests',
+    },
+  };
+
+  describe('findMetadataForMetric', () => {
+    it('should return histogram metadata for _bucket suffix', () => {
+      const result = findMetadataForMetric('http_request_duration_bucket', mockMetadata);
+      expect(result?.type).toBe('histogram');
+      expect(result?.help).toBe('Duration of HTTP requests');
+    });
+
+    it('should return histogram metadata for _count suffix', () => {
+      const result = findMetadataForMetric('http_request_duration_count', mockMetadata);
+      expect(result?.type).toBe('histogram');
+      expect(result?.help).toBe('Duration of HTTP requests');
+    });
+
+    it('should return histogram metadata for _sum suffix', () => {
+      const result = findMetadataForMetric('http_request_duration_sum', mockMetadata);
+      expect(result?.type).toBe('histogram');
+      expect(result?.help).toBe('Duration of HTTP requests');
+    });
+
+    it('should return exact match for non-histogram metrics', () => {
+      const result = findMetadataForMetric('cpu_usage', mockMetadata);
+      expect(result?.type).toBe('gauge');
+      expect(result?.help).toBe('CPU usage percentage');
+    });
+
+    it('should return counter metadata for counter metrics', () => {
+      const result = findMetadataForMetric('requests_total', mockMetadata);
+      expect(result?.type).toBe('counter');
+      expect(result?.help).toBe('Total number of requests');
+    });
+
+    it('should return undefined for non-existent metrics', () => {
+      const result = findMetadataForMetric('non_existent_metric', mockMetadata);
+      expect(result).toBeUndefined();
+    });
+  });
+
+  describe('getQueriesForMetric', () => {
+    it('should return histogram queries for _bucket suffix metrics', () => {
+      const result = getQueriesForMetric('http_request_duration_bucket', mockMetadata);
+      expect(result.length).toBeGreaterThan(0);
+      
+      // Check that we get histogram-specific queries
+      const percentileQuery = result.find(panel => panel.name === '95th percentile');
+      expect(percentileQuery).toBeDefined();
+      expect(percentileQuery?.targets[0].expr).toBe('histogram_quantile(0.95, rate(http_request_duration_bucket[5m]))');
+    });
+
+    it('should return histogram queries for _count suffix metrics', () => {
+      const result = getQueriesForMetric('http_request_duration_count', mockMetadata);
+      expect(result.length).toBeGreaterThan(0);
+      
+      // Check that we get histogram-specific queries with base metric name
+      const percentileQuery = result.find(panel => panel.name === '95th percentile');
+      expect(percentileQuery).toBeDefined();
+      expect(percentileQuery?.targets[0].expr).toBe('histogram_quantile(0.95, rate(http_request_duration_bucket[5m]))');
+    });
+
+    it('should return histogram queries for _sum suffix metrics', () => {
+      const result = getQueriesForMetric('http_request_duration_sum', mockMetadata);
+      expect(result.length).toBeGreaterThan(0);
+      
+      // Check that we get histogram-specific queries with base metric name
+      const averageQuery = result.find(panel => panel.name === 'Average');
+      expect(averageQuery).toBeDefined();
+      expect(averageQuery?.targets[0].expr).toBe('rate(http_request_duration_sum[5m]) / rate(http_request_duration_count[5m])');
+    });
+
+    it('should return gauge queries for gauge metrics', () => {
+      const result = getQueriesForMetric('cpu_usage', mockMetadata);
+      expect(result.length).toBeGreaterThan(0);
+      
+      // Check that we get gauge-specific queries
+      const currentValueQuery = result.find(panel => panel.name === 'Current value');
+      expect(currentValueQuery).toBeDefined();
+      expect(currentValueQuery?.targets[0].expr).toBe('cpu_usage');
+    });
+
+    it('should return counter queries for counter metrics', () => {
+      const result = getQueriesForMetric('requests_total', mockMetadata);
+      expect(result.length).toBeGreaterThan(0);
+      
+      // Check that we get counter-specific queries
+      const rateQuery = result.find(panel => panel.name === 'Rate per second');
+      expect(rateQuery).toBeDefined();
+      expect(rateQuery?.targets[0].expr).toBe('rate(requests_total[5m])');
+    });
+
+    it('should return empty array for non-existent metrics', () => {
+      const result = getQueriesForMetric('non_existent_metric', mockMetadata);
+      expect(result).toEqual([]);
+    });
+  });
+});

public/app/features/dashboard-scene/edit-pane/promQueries.ts

@@ -274,13 +274,31 @@ function findMetadataForMetric(
   metricName: string,
   metricsMetadata: PromMetricsMetadata
 ): PromMetricsMetadataItem | undefined {
-  // First try exact match
+  // For histogram/summary suffixes, prioritize finding the base metric first
+  // This ensures that metrics like 'http_request_duration_bucket' return 'histogram' type
+  // instead of the synthetic 'counter' type created for the suffixed metrics
+  const histogramSummarySuffixes = ['_bucket', '_count', '_sum'];
+  for (const suffix of histogramSummarySuffixes) {
+    if (metricName.endsWith(suffix)) {
+      const baseMetricName = metricName.slice(0, -suffix.length);
+      if (metricsMetadata[baseMetricName]) {
+        const baseMetadata = metricsMetadata[baseMetricName];
+        // Only return base metadata if it's actually a histogram or summary
+        if (baseMetadata.type === 'histogram' || baseMetadata.type === 'summary') {
+          return baseMetadata;
+        }
+      }
+    }
+  }
+
+  // Try exact match for non-histogram/summary metrics or when base metric isn't found
   if (metricsMetadata[metricName]) {
     return metricsMetadata[metricName];
   }
 
-  // Try removing common Prometheus suffixes to find the base metric
-  for (const suffix of PROMETHEUS_SUFFIXES) {
+  // Try removing other common Prometheus suffixes to find the base metric
+  const otherSuffixes = PROMETHEUS_SUFFIXES.filter(s => !histogramSummarySuffixes.includes(s));
+  for (const suffix of otherSuffixes) {
     if (metricName.endsWith(suffix)) {
       const baseMetricName = metricName.slice(0, -suffix.length);
       if (metricsMetadata[baseMetricName]) {
@@ -309,12 +327,24 @@ export function getQueriesForMetric(metricName: string, metricsMetadata: PromMet
     return [];
   }
 
+  // For histogram/summary metrics with suffixes, use the base metric name in queries
+  // since the query templates expect the base name (e.g., 'http_request_duration' not 'http_request_duration_bucket')
+  let queryMetricName = metricName;
+  if (metadata.type === 'histogram' || metadata.type === 'summary') {
+    const histogramSummarySuffixes = ['_bucket', '_count', '_sum'];
+    for (const suffix of histogramSummarySuffixes) {
+      if (metricName.endsWith(suffix)) {
+        queryMetricName = metricName.slice(0, -suffix.length);
+        break;
+      }
+    }
+  }
+
   return panels.map((panel) => ({
     ...panel,
-    // name: `${metricName} - ${panel.name}`,
     targets: panel.targets.map((target) => ({
       ...target,
-      expr: target.expr.replace(/\{\{metric_name\}\}/g, metricName),
+      expr: target.expr.replace(/\{\{metric_name\}\}/g, queryMetricName),
     })),
   }));
 }