Jaeger: Make tags templateable (#42005)

* make tags templateable

* cleanup files I didn't want to modify

public/app/plugins/datasource/jaeger/datasource.test.ts

@@ -1,5 +1,12 @@
 import { lastValueFrom, of, throwError } from 'rxjs';
-import { DataQueryRequest, DataSourceInstanceSettings, dateTime, FieldType, PluginType } from '@grafana/data';
+import {
+  DataQueryRequest,
+  DataSourceInstanceSettings,
+  dateTime,
+  FieldType,
+  PluginType,
+  ScopedVars,
+} from '@grafana/data';
 
 import { backendSrv } from 'app/core/services/backend_srv';
 import { createFetchResponse } from 'test/helpers/createFetchResponse';
@@ -15,8 +22,13 @@ import {
 import { JaegerQuery } from './types';
 
 jest.mock('@grafana/runtime', () => ({
-  ...((jest.requireActual('@grafana/runtime') as unknown) as object),
+  ...(jest.requireActual('@grafana/runtime') as any),
   getBackendSrv: () => backendSrv,
+  getTemplateSrv: () => ({
+    replace: (val: string, subs: ScopedVars): string => {
+      return subs[val]?.value ?? val;
+    },
+  }),
 }));
 
 const timeSrvStub: any = {
@@ -146,6 +158,26 @@ describe('JaegerDatasource', () => {
       url: `${defaultSettings.url}/api/traces?service=jaeger-query&tags=%7B%22error%22%3A%22true%22%7D&start=1531468681000&end=1531489712000&lookback=custom`,
     });
   });
+
+  it('should resolve templates in tags', async () => {
+    const mock = setupFetchMock({ data: [testResponse] });
+    const ds = new JaegerDatasource(defaultSettings, timeSrvStub);
+    await lastValueFrom(
+      ds.query({
+        ...defaultQuery,
+        scopedVars: {
+          'error=$error': {
+            text: 'error',
+            value: 'error=true',
+          },
+        },
+        targets: [{ queryType: 'search', refId: 'a', service: 'jaeger-query', tags: 'error=$error' }],
+      })
+    );
+    expect(mock).toBeCalledWith({
+      url: `${defaultSettings.url}/api/traces?service=jaeger-query&tags=%7B%22error%22%3A%22true%22%7D&start=1531468681000&end=1531489712000&lookback=custom`,
+    });
+  });
 });
 
 describe('when performing testDataSource', () => {

public/app/plugins/datasource/jaeger/datasource.ts

@@ -12,7 +12,7 @@ import {
   FieldType,
   MutableDataFrame,
 } from '@grafana/data';
-import { BackendSrvRequest, getBackendSrv } from '@grafana/runtime';
+import { BackendSrvRequest, getBackendSrv, getTemplateSrv } from '@grafana/runtime';
 
 import { serializeParams } from 'app/core/utils/fetch';
 import { getTimeSrv, TimeSrv } from 'app/features/dashboard/services/TimeSrv';
@@ -46,7 +46,7 @@ export class JaegerDatasource extends DataSourceApi<JaegerQuery, JaegerJsonData>
   query(options: DataQueryRequest<JaegerQuery>): Observable<DataQueryResponse> {
     // At this moment we expect only one target. In case we somehow change the UI to be able to show multiple
     // traces at one we need to change this.
-    const target = options.targets[0];
+    const target: JaegerQuery = options.targets[0];
     if (!target) {
       return of({ data: [emptyTraceDataFrame] });
     }
@@ -90,7 +90,10 @@ export class JaegerDatasource extends DataSourceApi<JaegerQuery, JaegerJsonData>
     // remove empty properties
     jaegerQuery = pickBy(jaegerQuery, identity);
     if (jaegerQuery.tags) {
-      jaegerQuery = { ...jaegerQuery, tags: convertTagsLogfmt(jaegerQuery.tags) };
+      jaegerQuery = {
+        ...jaegerQuery,
+        tags: convertTagsLogfmt(getTemplateSrv().replace(jaegerQuery.tags, options.scopedVars)),
+      };
     }
 
     if (jaegerQuery.operation === ALL_OPERATIONS_KEY) {