Adds unit tests to test datasource

public/app/plugins/datasource/stackdriver/datasource.ts

@@ -2,18 +2,14 @@
 export default class StackdriverDatasource {
   url: string;
   baseUrl: string;
-  cloudName: string;
 
   constructor(instanceSettings, private backendSrv) {
-    this.cloudName = 'stackdriver';
-    this.baseUrl = `/${this.cloudName}/`;
+    this.baseUrl = `/stackdriver/`;
     this.url = instanceSettings.url;
   }
 
   testDatasource() {
-    const path = `v3/projects/raintank-production/timeSeries?aggregation.crossSeriesReducer=
-    REDUCE_NONE&filter=metric.type%20%3D%20%22compute.googleapis.com%2Finstance%2Fcpu%2Fusage_time%
-    22&aggregation.perSeriesAligner=ALIGN_NONE&interval.startTime=2018-09-04T05%3A16%3A02.383Z&interval.endTime=2018-09-04T11%3A16%3A02.383Z`;
+    const path = `v3/projects/raintank-production/metricDescriptors`;
     return this.doRequest(`${this.baseUrl}${path}`)
       .then(response => {
         if (response.status === 200) {
@@ -22,22 +18,17 @@ export default class StackdriverDatasource {
             message: 'Successfully queried the Azure Monitor service.',
             title: 'Success',
           };
-        } else {
-          throw new Error();
         }
       })
       .catch(error => {
-        let message = 'Azure Monitor: ';
+        let message = 'Stackdriver: ';
         message += error.statusText ? error.statusText + ': ' : '';
 
         if (error.data && error.data.error && error.data.error.code) {
+          // 400, 401
           message += error.data.error.code + '. ' + error.data.error.message;
-        } else if (error.data && error.data.error) {
-          message += error.data.error;
-        } else if (error.data) {
-          message += error.data;
         } else {
-          message += 'Cannot connect to Azure Monitor REST API.';
+          message += 'Cannot connect to Stackdriver API';
         }
         return {
           status: 'error',

public/app/plugins/datasource/stackdriver/specs/datasource.test.ts

+import StackdriverDataSource from '../datasource';
+import { metricDescriptors } from './testData';
+
+describe('StackdriverDataSource', () => {
+  describe('when performing testDataSource', () => {
+    describe('and call to stackdriver api succeeds', () => {
+      let ds;
+      let result;
+      beforeEach(async () => {
+        const backendSrv = {
+          async datasourceRequest() {
+            return Promise.resolve({ status: 200 });
+          },
+        };
+        ds = new StackdriverDataSource({}, backendSrv);
+        result = await ds.testDatasource();
+      });
+      it('should return successfully', () => {
+        expect(result.status).toBe('success');
+      });
+    });
+
+    describe('and a list of metricDescriptors are returned', () => {
+      let ds;
+      let result;
+      beforeEach(async () => {
+        console.log('erik', metricDescriptors);
+        const backendSrv = {
+          datasourceRequest: async () => Promise.resolve({ status: 200, data: metricDescriptors }),
+        };
+        ds = new StackdriverDataSource({}, backendSrv);
+        result = await ds.testDatasource();
+      });
+      it('should return status success', () => {
+        expect(result.status).toBe('success');
+      });
+    });
+
+    describe('and call to stackdriver api fails with 400 error', () => {
+      let ds;
+      let result;
+      beforeEach(async () => {
+        const backendSrv = {
+          datasourceRequest: async () =>
+            Promise.reject({
+              statusText: 'Bad Request',
+              data: { error: { code: 400, message: 'Field interval.endTime had an invalid value' } },
+            }),
+        };
+        ds = new StackdriverDataSource({}, backendSrv);
+        result = await ds.testDatasource();
+      });
+
+      it('should return error status and a detailed error message', () => {
+        expect(result.status).toEqual('error');
+        expect(result.message).toBe('Stackdriver: Bad Request: 400. Field interval.endTime had an invalid value');
+      });
+    });
+  });
+});

public/app/plugins/datasource/stackdriver/specs/testData.ts

+export const metricDescriptors = [
+  {
+    name: 'projects/raintank-production/metricDescriptors/agent.googleapis.com/agent/api_request_count',
+    labels: [
+      {
+        key: 'state',
+        description: 'Request state',
+      },
+    ],
+    metricKind: 'CUMULATIVE',
+    valueType: 'INT64',
+    unit: '1',
+    description: 'API request count',
+    displayName: 'API Request Count',
+    type: 'agent.googleapis.com/agent/api_request_count',
+    metadata: {
+      launchStage: 'GA',
+      samplePeriod: '60s',
+      ingestDelay: '0s',
+    },
+  },
+  {
+    name: 'projects/raintank-production/metricDescriptors/agent.googleapis.com/agent/log_entry_count',
+    labels: [
+      {
+        key: 'response_code',
+        description: 'HTTP response code',
+      },
+    ],
+    metricKind: 'CUMULATIVE',
+    valueType: 'INT64',
+    unit: '1',
+    description: 'Count of log entry writes',
+    displayName: 'Log Entry Count',
+    type: 'agent.googleapis.com/agent/log_entry_count',
+    metadata: {
+      launchStage: 'GA',
+      samplePeriod: '60s',
+      ingestDelay: '0s',
+    },
+  },
+];