From 1ea5c2e69c9ca2f88c094ea0676039630ecab012 Mon Sep 17 00:00:00 2001
From: Otavio Macedo <otaviom@amazon.com>
Date: Tue, 16 Feb 2021 10:57:33 +0000
Subject: [PATCH] fix(aws-cloudwatch): respect the period of MathExpressions
 #9156

---
 .../aws-cloudwatch/lib/private/rendering.ts   |  1 +
 ...teg.math-alarm-and-dashboard.expected.json |  4 ++--
 .../aws-cloudwatch/test/test.metric-math.ts   | 22 +++++++++++++++++++
 3 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/packages/@aws-cdk/aws-cloudwatch/lib/private/rendering.ts b/packages/@aws-cdk/aws-cloudwatch/lib/private/rendering.ts
index e8dcb15cabc84..8553d9ad5c486 100644
--- a/packages/@aws-cdk/aws-cloudwatch/lib/private/rendering.ts
+++ b/packages/@aws-cdk/aws-cloudwatch/lib/private/rendering.ts
@@ -55,6 +55,7 @@ function metricGraphJson(metric: IMetric, yAxis?: string, id?: string) {
 
     withExpression(expr) {
       options.expression = expr.expression;
+      if (expr.period && expr.period !== 300) { options.period = expr.period; }
     },
   });
 
diff --git a/packages/@aws-cdk/aws-cloudwatch/test/integ.math-alarm-and-dashboard.expected.json b/packages/@aws-cdk/aws-cloudwatch/test/integ.math-alarm-and-dashboard.expected.json
index 7de0e4290cd65..8e9b235bb2b65 100644
--- a/packages/@aws-cdk/aws-cloudwatch/test/integ.math-alarm-and-dashboard.expected.json
+++ b/packages/@aws-cdk/aws-cloudwatch/test/integ.math-alarm-and-dashboard.expected.json
@@ -88,7 +88,7 @@
               {
                 "Ref": "AWS::Region"
               },
-              "\",\"metrics\":[[{\"label\":\"Total Messages\",\"expression\":\"m1+m2\"}],[\"AWS/SQS\",\"ApproximateNumberOfMessagesVisible\",\"QueueName\",\"",
+              "\",\"metrics\":[[{\"label\":\"Total Messages\",\"expression\":\"m1+m2\",\"period\":60}],[\"AWS/SQS\",\"ApproximateNumberOfMessagesVisible\",\"QueueName\",\"",
               {
                 "Fn::GetAtt": [
                   "queue",
@@ -120,7 +120,7 @@
               {
                 "Ref": "AWS::Region"
               },
-              "\",\"metrics\":[[{\"label\":\"Total Messages\",\"expression\":\"m1+m2\"}],[\"AWS/SQS\",\"ApproximateNumberOfMessagesVisible\",\"QueueName\",\"",
+              "\",\"metrics\":[[{\"label\":\"Total Messages\",\"expression\":\"m1+m2\",\"period\":60}],[\"AWS/SQS\",\"ApproximateNumberOfMessagesVisible\",\"QueueName\",\"",
               {
                 "Fn::GetAtt": [
                   "queue",
diff --git a/packages/@aws-cdk/aws-cloudwatch/test/test.metric-math.ts b/packages/@aws-cdk/aws-cloudwatch/test/test.metric-math.ts
index e8288ce092b27..b5eecac9ec52d 100644
--- a/packages/@aws-cdk/aws-cloudwatch/test/test.metric-math.ts
+++ b/packages/@aws-cdk/aws-cloudwatch/test/test.metric-math.ts
@@ -219,6 +219,28 @@ export = {
       test.done();
     },
 
+    'top level period in a MathExpression is respected in its metrics'(test: Test) {
+      const graph = new GraphWidget({
+        left: [
+          a,
+          new MathExpression({
+            expression: 'a + b',
+            usingMetrics: { a, b },
+            period: Duration.minutes(1),
+          }),
+        ],
+      });
+
+      // THEN
+      graphMetricsAre(test, graph, [
+        ['Test', 'ACount'],
+        [{ label: 'a + b', expression: 'a + b', period: 60 }],
+        ['Test', 'ACount', { visible: false, id: 'a', period: 60 }],
+        ['Test', 'BCount', { visible: false, id: 'b', period: 60 }],
+      ]);
+      test.done();
+    },
+
     'MathExpression controls period of metrics transitively used in it'(test: Test) {
       // Same as the previous test, but recursively