feat(cloudwatch): full precision for SingleValueWidgets

packages/@aws-cdk/aws-cloudwatch/README.md

@@ -324,6 +324,17 @@ dashboard.addWidgets(new SingleValueWidget({
 }));
 ```
 
+Show as many digits as can fit, before rounding.
+
+```ts
+dashboard.addWidgets(new SingleValueWidget({
+  // ..
+  // ..
+
+  fullPrecision: true,
+}));
+```
+
 ### Text widget
 
 A text widget shows an arbitrary piece of MarkDown. Use this to add explanations

packages/@aws-cdk/aws-cloudwatch/lib/graph.ts

@@ -296,6 +296,13 @@ export interface SingleValueWidgetProps extends MetricWidgetProps {
    * @default false
    */
   readonly setPeriodToTimeRange?: boolean;
+
+  /**
+   * Whether to show as many digits as can fit, before rounding.
+   *
+   * @default false
+   */
+  readonly fullPrecision?: boolean;
 }
 
 /**
@@ -322,6 +329,7 @@ export class SingleValueWidget extends ConcreteWidget {
         region: this.props.region || cdk.Aws.REGION,
         metrics: allMetricsGraphJson(this.props.metrics, []),
         setPeriodToTimeRange: this.props.setPeriodToTimeRange,
+        singleValueFullPrecision: this.props.fullPrecision,
       },
     }];
   }

packages/@aws-cdk/aws-cloudwatch/test/integ.alarm-and-dashboard.expected.json

@@ -87,7 +87,29 @@
               {
                 "Ref": "AWS::Region"
               },
-              "\",\"query\":\"SOURCE 'my-log-group' | fields @message\\n                | filter @message like /Error/\"}}]}"
+              "\",\"query\":\"SOURCE 'my-log-group' | fields @message\\n                | filter @message like /Error/\"}},{\"type\":\"metric\",\"width\":6,\"height\":3,\"x\":0,\"y\":47,\"properties\":{\"view\":\"singleValue\",\"title\":\"Sent message size\",\"region\":\"",
+              {
+                "Ref": "AWS::Region"
+              },
+              "\",\"metrics\":[[\"AWS/SQS\",\"SentMessageSize\",\"QueueName\",\"",
+              {
+                "Fn::GetAtt": [
+                  "queue",
+                  "QueueName"
+                ]
+              },
+              "\"]],\"singleValueFullPrecision\":false}},{\"type\":\"metric\",\"width\":6,\"height\":3,\"x\":0,\"y\":50,\"properties\":{\"view\":\"singleValue\",\"title\":\"Sent message size with full precision\",\"region\":\"",
+              {
+                "Ref": "AWS::Region"
+              },
+              "\",\"metrics\":[[\"AWS/SQS\",\"SentMessageSize\",\"QueueName\",\"",
+              {
+                "Fn::GetAtt": [
+                  "queue",
+                  "QueueName"
+                ]
+              },
+              "\"]],\"singleValueFullPrecision\":true}}]}"
             ]
           ]
         },

packages/@aws-cdk/aws-cloudwatch/test/integ.alarm-and-dashboard.ts

@@ -13,13 +13,19 @@ const stack = new cdk.Stack(app, 'aws-cdk-cloudwatch-alarms');
 
 const queue = new cdk.CfnResource(stack, 'queue', { type: 'AWS::SQS::Queue' });
 
-const metric = new cloudwatch.Metric({
+const numberOfMessagesVisibleMetric = new cloudwatch.Metric({
   namespace: 'AWS/SQS',
   metricName: 'ApproximateNumberOfMessagesVisible',
   dimensions: { QueueName: queue.getAtt('QueueName') },
 });
 
-const alarm = metric.createAlarm(stack, 'Alarm', {
+const sentMessageSizeMetric = new cloudwatch.Metric({
+  namespace: 'AWS/SQS',
+  metricName: 'SentMessageSize',
+  dimensions: { QueueName: queue.getAtt('QueueName') },
+});
+
+const alarm = numberOfMessagesVisibleMetric.createAlarm(stack, 'Alarm', {
   threshold: 100,
   evaluationPeriods: 3,
   datapointsToAlarm: 2,
@@ -41,12 +47,12 @@ dashboard.addWidgets(new cloudwatch.AlarmWidget({
 }));
 dashboard.addWidgets(new cloudwatch.GraphWidget({
   title: 'More messages in queue with alarm annotation',
-  left: [metric],
+  left: [numberOfMessagesVisibleMetric],
   leftAnnotations: [alarm.toAnnotation()],
 }));
 dashboard.addWidgets(new cloudwatch.SingleValueWidget({
   title: 'Current messages in queue',
-  metrics: [metric],
+  metrics: [numberOfMessagesVisibleMetric],
 }));
 dashboard.addWidgets(new cloudwatch.LogQueryWidget({
   title: 'Errors in my log group',
@@ -82,5 +88,15 @@ dashboard.addWidgets(new cloudwatch.LogQueryWidget({
   queryString: `fields @message
                 | filter @message like /Error/`,
 }));
+dashboard.addWidgets(new cloudwatch.SingleValueWidget({
+  title: 'Sent message size',
+  metrics: [sentMessageSizeMetric],
+  fullPrecision: false,
+}));
+dashboard.addWidgets(new cloudwatch.SingleValueWidget({
+  title: 'Sent message size with full precision',
+  metrics: [sentMessageSizeMetric],
+  fullPrecision: true,
+}));
 
 app.synth();

packages/@aws-cdk/aws-cloudwatch/test/test.graphs.ts

@@ -557,6 +557,35 @@ export = {
     test.done();
   },
 
+  'add singleValueFullPrecision to singleValueWidget'(test: Test) {
+    // GIVEN
+    const stack = new Stack();
+    const metric = new Metric({ namespace: 'CDK', metricName: 'Test' });
+
+    // WHEN
+    const widget = new SingleValueWidget({
+      metrics: [metric],
+      fullPrecision: true,
+    });
+
+    // THEN
+    test.deepEqual(stack.resolve(widget.toJson()), [{
+      type: 'metric',
+      width: 6,
+      height: 3,
+      properties: {
+        view: 'singleValue',
+        region: { Ref: 'AWS::Region' },
+        metrics: [
+          ['CDK', 'Test'],
+        ],
+        singleValueFullPrecision: true,
+      },
+    }]);
+
+    test.done();
+  },
+
   'allows overriding custom values of dashboard widgets'(test: Test) {
     class HiddenMetric extends Metric {
       public toMetricConfig() {