fix(aws-events): support newlines in textTemplate

Support newlines in CloudWatch Events textTemplate as intended, by making a newline-separated list of JSON strings. Fixes #1514.
aws · Jan 18, 2019 · ef52892 · ef52892
1 parent 33c2a6d
commit ef52892
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Showing 5 changed files with 123 additions and 3 deletions.
diff --git a/examples/cdk-examples-typescript/cloudwatch-events/cdk.json b/examples/cdk-examples-typescript/cloudwatch-events/cdk.json
@@ -0,0 +1,3 @@
+{
+  "app": "node index"
+}
diff --git a/examples/cdk-examples-typescript/cloudwatch-events/index.ts b/examples/cdk-examples-typescript/cloudwatch-events/index.ts
@@ -0,0 +1,25 @@
+import events = require('@aws-cdk/aws-events');
+import sns = require('@aws-cdk/aws-sns');
+import cdk = require('@aws-cdk/cdk');
+
+const app = new cdk.App();
+
+class CloudWatchEventsExample extends cdk.Stack {
+  constructor(scope: cdk.App, id: string) {
+    super(scope, id);
+
+    const topic = new sns.Topic(this, 'TestTopic');
+
+    const event = new events.EventRule(this, 'Rule', {
+      scheduleExpression: 'rate(1 minute)'
+    });
+
+    event.addTarget(topic, {
+      textTemplate: 'one line\nsecond line'
+    });
+  }
+}
+
+new CloudWatchEventsExample(app, 'CWE-Example');
+
+app.run();
diff --git a/examples/cdk-examples-typescript/package.json b/examples/cdk-examples-typescript/package.json
@@ -37,6 +37,7 @@
     "@aws-cdk/aws-rds": "^0.22.0",
     "@aws-cdk/aws-s3": "^0.22.0",
     "@aws-cdk/aws-sns": "^0.22.0",
+    "@aws-cdk/aws-events": "^0.22.0",
     "@aws-cdk/aws-sqs": "^0.22.0",
     "@aws-cdk/cdk": "^0.22.0",
     "@aws-cdk/runtime-values": "^0.22.0"

diff --git a/packages/@aws-cdk/aws-events/lib/rule.ts b/packages/@aws-cdk/aws-events/lib/rule.ts
@@ -147,7 +147,8 @@ export class EventRule extends Construct implements IEventRule {
       if (inputOptions.jsonTemplate) {
         inputTemplate = inputOptions.jsonTemplate;
       } else if (typeof(inputOptions.textTemplate) === 'string') {
-        inputTemplate = JSON.stringify(inputOptions.textTemplate);
+        // Newline separated list of JSON-encoded strings
+        inputTemplate = inputOptions.textTemplate.split('\n').map(x => JSON.stringify(x)).join('\n');
       } else {
         inputTemplate = `"${inputOptions.textTemplate}"`;
       }

diff --git a/packages/@aws-cdk/aws-events/test/test.rule.ts b/packages/@aws-cdk/aws-events/test/test.rule.ts
@@ -1,4 +1,4 @@
-import { expect, haveResource } from '@aws-cdk/assert';
+import { expect, haveResource, haveResourceLike } from '@aws-cdk/assert';
 import cdk = require('@aws-cdk/cdk');
 import { Stack } from '@aws-cdk/cdk';
 import { Test } from 'nodeunit';
@@ -351,5 +351,95 @@ export = {
     test.deepEqual(importedRule.ruleArn, 'arn:of:rule');
 
     test.done();
-  }
+  },
+
+  'text templates': {
+    'strings with newlines are serialized to a newline-delimited list of JSON strings'(test: Test) {
+      // GIVEN
+      const stack = new Stack();
+      const rule = new EventRule(stack, 'Rule', {
+        scheduleExpression: 'rate(1 minute)'
+      });
+
+      // WHEN
+      rule.addTarget(new SomeTarget(), {
+        textTemplate: 'I have\nmultiple lines',
+      });
+
+      // THEN
+      expect(stack).to(haveResourceLike('AWS::Events::Rule', {
+        Targets: [
+          {
+            InputTransformer: {
+              InputTemplate: "\"I have\"\n\"multiple lines\""
+            },
+          }
+        ]
+      }));
+
+      test.done();
+    },
+
+    'escaped newlines are not interpreted as newlines'(test: Test) {
+      // GIVEN
+      const stack = new Stack();
+      const rule = new EventRule(stack, 'Rule', {
+        scheduleExpression: 'rate(1 minute)'
+      });
+
+      // WHEN
+      rule.addTarget(new SomeTarget(), {
+        textTemplate: 'this is not\\na real newline',
+      });
+
+      // THEN
+      expect(stack).to(haveResourceLike('AWS::Events::Rule', {
+        Targets: [
+          {
+            InputTransformer: {
+              InputTemplate: "\"this is not\\\\na real newline\""
+            },
+          }
+        ]
+      }));
+
+      test.done();
+    },
+
+    'can use Tokens in text templates'(test: Test) {
+      // GIVEN
+      const stack = new Stack();
+      const rule = new EventRule(stack, 'Rule', {
+        scheduleExpression: 'rate(1 minute)'
+      });
+
+      const world = new cdk.Token(() => 'world');
+
+      // WHEN
+      rule.addTarget(new SomeTarget(), {
+        textTemplate: `hello ${world}`,
+      });
+
+      // THEN
+      expect(stack).to(haveResourceLike('AWS::Events::Rule', {
+        Targets: [
+          {
+            InputTransformer: {
+              InputTemplate: "\"hello world\""
+            },
+          }
+        ]
+      }));
+
+      test.done();
+    }
+  },
 };
+
+class SomeTarget implements IEventRuleTarget {
+  public asEventRuleTarget() {
+    return {
+      id: 'T1', arn: 'ARN1', kinesisParameters: { partitionKeyPath: 'partitionKeyPath' }
+    };
+  }
+}