update metrics with async calls

Author: eduardomourar

src/metrics.ts

@@ -25,15 +25,15 @@ export class MetricPublisher {
         this.client = session.client('CloudWatch') as CloudWatch;
     }
 
-    publishMetric(
+    async publishMetric(
         metricName: MetricTypes,
         dimensions: Map<string, string>,
         unit: StandardUnit,
         value: number,
         timestamp: Date,
-    ): void {
+    ): Promise<void> {
         try {
-            this.client.putMetricData({
+            const metric = await this.client.putMetricData({
                 Namespace: this.namespace,
                 MetricData: [{
                     MetricName: metricName,
@@ -42,7 +42,7 @@ export class MetricPublisher {
                     Timestamp: timestamp,
                     Value: value,
                 }],
-            });
+            }).promise();
         } catch(err) {
             LOGGER.error(`An error occurred while publishing metrics: ${err.message}`);
         }
@@ -56,7 +56,7 @@ export class MetricsPublisherProxy {
     constructor(public accountId: string, public resourceType: string) {
         this.namespace = MetricsPublisherProxy.makeNamespace(accountId, resourceType);
         this.resourceType = resourceType;
-        this.publishers = [];   
+        this.publishers = [];
     }
 
     static makeNamespace(accountId: string, resourceType: string): string {

tests/lib/metrics.test.ts

@@ -64,21 +64,23 @@ describe('when getting metrics', () => {
         ]);
     });
 
-    test('put metric catches error', () => {
+    test('put metric catches error', async () => {
         const spyConsoleError: jest.SpyInstance = jest
             .spyOn(global.console, 'error').mockImplementation(() => {});
-        putMetricData.mockImplementationOnce(() => {
-            throw awsUtil.error(new Error(), {
-                code: 'InternalServiceError',
-                message: 'An error occurred (InternalServiceError) when '
-                    + 'calling the PutMetricData operation: ',
-            });
+        putMetricData.mockReturnValueOnce({
+            promise: jest.fn().mockRejectedValueOnce(
+                awsUtil.error(new Error(), {
+                    code: 'InternalServiceError',
+                    message: 'An error occurred (InternalServiceError) when '
+                        + 'calling the PutMetricData operation: ',
+                })
+            )
         });
         const publisher = new MetricPublisher(session, NAMESPACE);
         const dimensions = new Map<string, string>();
         dimensions.set('DimensionKeyActionType', Action.Create);
         dimensions.set('DimensionKeyResourceType', RESOURCE_TYPE);
-        publisher.publishMetric(
+        await publisher.publishMetric(
             MetricTypes.HandlerInvocationCount,
             dimensions,
             StandardUnit.Count,
@@ -115,7 +117,7 @@ describe('when getting metrics', () => {
     test('publish exception metric', () => {
         const proxy = new MetricsPublisherProxy(ACCOUNT_ID, RESOURCE_TYPE);
         proxy.addMetricsPublisher(session);
-        proxy.publishExceptionMetric( MOCK_DATE, Action.Create, new Error('fake-err'));
+        proxy.publishExceptionMetric(MOCK_DATE, Action.Create, new Error('fake-err'));
         expect(putMetricData).toHaveBeenCalledTimes(1);
         expect(putMetricData).toHaveBeenCalledWith({
             MetricData: [{
@@ -145,7 +147,7 @@ describe('when getting metrics', () => {
     test('publish invocation metric', () => {
         const proxy = new MetricsPublisherProxy(ACCOUNT_ID, RESOURCE_TYPE);
         proxy.addMetricsPublisher(session);
-        proxy.publishInvocationMetric( MOCK_DATE, Action.Create);
+        proxy.publishInvocationMetric(MOCK_DATE, Action.Create);
         expect(putMetricData).toHaveBeenCalledTimes(1);
         expect(putMetricData).toHaveBeenCalledWith({
             MetricData: [{
@@ -194,7 +196,6 @@ describe('when getting metrics', () => {
         });
     });
 
-
     test('publish log delivery exception metric', () => {
         const proxy = new MetricsPublisherProxy(ACCOUNT_ID, RESOURCE_TYPE);
         proxy.addMetricsPublisher(session);