From 036e19037ed702bf4b63f16cc8b3b6f9d7b785db Mon Sep 17 00:00:00 2001
From: Andre Pereira <adrapereira@gmail.com>
Date: Thu, 29 Feb 2024 12:41:31 +0000
Subject: [PATCH] Tempo: Better fallbacks for metrics query (#83619)

* Use query as fallback when there's one series and no labels. Use "" as the fallback for empty label values. Stop using the `promLabels` value from the Tempo response

* Set refId to remove mentions of promLabels

* Add quotes around the string value, add space after comma separator

* Use name as refId when possible
---
 .../plugins/datasource/tempo/datasource.ts    |  2 +-
 .../datasource/tempo/resultTransformer.ts     | 32 ++++++++++++-------
 2 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/public/app/plugins/datasource/tempo/datasource.ts b/public/app/plugins/datasource/tempo/datasource.ts
index d2ada1f496b..96fcb05b88c 100644
--- a/public/app/plugins/datasource/tempo/datasource.ts
+++ b/public/app/plugins/datasource/tempo/datasource.ts
@@ -714,7 +714,7 @@ export class TempoDatasource extends DataSourceWithBackend<TempoQuery, TempoJson
     }).pipe(
       map((response) => {
         return {
-          data: formatTraceQLMetrics(response.data),
+          data: formatTraceQLMetrics(queryValue, response.data),
         };
       }),
       catchError((err) => {
diff --git a/public/app/plugins/datasource/tempo/resultTransformer.ts b/public/app/plugins/datasource/tempo/resultTransformer.ts
index 187c20b711a..fd47cdd3b0f 100644
--- a/public/app/plugins/datasource/tempo/resultTransformer.ts
+++ b/public/app/plugins/datasource/tempo/resultTransformer.ts
@@ -633,21 +633,31 @@ function transformToTraceData(data: TraceSearchMetadata) {
 }
 
 const metricsValueToString = (value: ProtoValue): string => {
-  return '' + (value.stringValue || value.intValue || value.doubleValue || value.boolValue || '');
+  if (value.stringValue) {
+    return `"${value.stringValue}"`;
+  }
+  return '' + (value.intValue || value.doubleValue || value.boolValue || '""');
 };
 
-export function formatTraceQLMetrics(data: TraceqlMetricsResponse) {
-  const frames = data.series.map((series) => {
+export function formatTraceQLMetrics(query: string, data: TraceqlMetricsResponse) {
+  const frames = data.series.map((series, index) => {
     const labels: Labels = {};
-    series.labels.forEach((label) => {
+    series.labels?.forEach((label) => {
       labels[label.key] = metricsValueToString(label.value);
     });
-    const displayName =
-      series.labels.length === 1
-        ? metricsValueToString(series.labels[0].value)
-        : `{${series.labels.map((label) => `${label.key}=${metricsValueToString(label.value)}`).join(',')}}`;
+    // If it's a single series, use the query as the displayName fallback
+    let name = data.series.length === 1 ? query : '';
+    if (series.labels) {
+      if (series.labels.length === 1) {
+        // For single label series, use the label value as the displayName to improve readability
+        name = metricsValueToString(series.labels[0].value);
+      } else {
+        // otherwise build a string using the label keys and values
+        name = `{${series.labels.map((label) => `${label.key}=${metricsValueToString(label.value)}`).join(', ')}}`;
+      }
+    }
     return createDataFrame({
-      refId: series.promLabels,
+      refId: name || `A${index}`,
       fields: [
         {
           name: 'time',
@@ -655,12 +665,12 @@ export function formatTraceQLMetrics(data: TraceqlMetricsResponse) {
           values: series.samples.map((sample) => parseInt(sample.timestampMs, 10)),
         },
         {
-          name: series.promLabels,
+          name: name,
           labels,
           type: FieldType.number,
           values: series.samples.map((sample) => sample.value),
           config: {
-            displayNameFromDS: displayName,
+            displayNameFromDS: name,
           },
         },
       ],