feat: Extracts forwarder stack

src/config.ts

@@ -19,6 +19,7 @@ const CONFIG_DEFAULTS: DatadogIntegrationDefaults = Object.freeze({
   forwarderName: 'DatadogForwarder',
   forwarderVersion: 'latest',
   installDatadogPolicyMacro: true,
+  installDatadogForwarder: true,
 });
 
 export type DatadogIntegrationConfigWithDefaults = DatadogIntegrationConfig &

src/forwarder.ts

@@ -0,0 +1,53 @@
+import * as cfn from 'aws-cdk-lib/aws-cloudformation';
+import { Construct } from 'constructs';
+
+export interface ForwarderStackProps extends Omit<cfn.CfnStackProps, 'templateUrl'>{
+  forwarderVersion: string;
+  templateParameters: ForwarderTemplateParameters;
+}
+
+export interface ForwarderTemplateParameters{
+  /**
+     * The Datadog API key, which can be found from the APIs page (/account/settings#api). It will be stored in AWS Secrets Manager securely. If DdApiKeySecretArn is also set, this value will not be used. This value must still be set, however.
+     * @default 'USE_ARN'
+     */
+  DdApiKey?: string;
+
+  /**
+     * The ARN of the secret storing the Datadog API key, if you already have it stored in Secrets Manager. You still need to set a dummy value for "DdApiKey" to satisfy the requirement, though that value won't be used.
+     */
+  DdApiKeySecretArn?: string;
+
+  /**
+     *  The Datadog Forwarder Lambda function name. DO NOT change when updating an existing CloudFormation stack, otherwise the current forwarder function will be replaced and all the triggers will be lost.
+     * @default DatadogForwarder
+     */
+  FunctionName?: string;
+
+  /**
+     * Define your Datadog Site to send data to. For the Datadog EU site, set to datadoghq.eu
+     * @default datadoghq.com
+     */
+  DdSite?: string;
+}
+export class ForwarderStack extends cfn.CfnStack {
+
+  constructor(scope: Construct, id: string, props: ForwarderStackProps) {
+
+    const templateParams: ForwarderTemplateParameters = {
+      DdApiKey: 'USE_ARN',
+      DdApiKeySecretArn: props.templateParameters.DdApiKeySecretArn,
+      DdSite: props.templateParameters.DdSite,
+      FunctionName: props.templateParameters.DdSite,
+      ...props.templateParameters,
+    };
+
+    const templateParamsAsDict: { [key: string]: (string) } = Object.entries(templateParams)
+      .reduce((all, [key, value]) => ({ ...all, [key]: value.toString() }), {});
+
+    super(scope, id, {
+      templateUrl: `https://datadog-cloudformation-template.s3.amazonaws.com/aws/forwarder/${props.forwarderVersion}.yaml`,
+      parameters: templateParamsAsDict,
+    });
+  }
+}

src/index.ts

@@ -7,6 +7,7 @@ import {
   applyDefaultsToConfig,
   DatadogIntegrationConfigWithDefaults,
 } from './config';
+import * as forwarder from './forwarder';
 import { bucketsToString } from './util';
 
 type DatadogPermissionsLevel = 'Full' | 'Core';
@@ -63,6 +64,14 @@ export interface DatadogIntegrationConfig {
    */
   readonly forwarderVersion?: string;
 
+  /**
+   * If you already deployed a stack using this template, or you want to deploy the ForwarderStack separately, set this parameter to false
+   * to skip the installation of the DatadogForwarder again
+   *
+   * @default true
+   */
+  readonly installDatadogForwarder?: boolean;
+
   /**
    * If you already deployed a stack using this template, set this parameter to false
    * to skip the installation of the DatadogPolicy Macro again
@@ -93,9 +102,7 @@ export interface DatadogIntegrationConfig {
    * See https://datadog-cloudformation-template.s3.amazonaws.com/aws/forwarder/latest.yaml
    * for the latest parameters.
    */
-  readonly additionalForwarderParams?: {
-    [key: string]: string;
-  };
+  readonly additionalForwarderParams?: forwarder.ForwarderTemplateParameters;
 
   /**
    * Additional parameters to pass through to the underlying Integration Role CloudFormation
@@ -127,7 +134,10 @@ export class DatadogIntegration extends Construct {
     }
 
     this.createIntegrationRole(propsWithDefaults, policyMacroStack);
-    this.createForwarderStack(propsWithDefaults);
+
+    if (propsWithDefaults.installDatadogForwarder) {
+      this.createForwarderStack(propsWithDefaults);
+    }
   }
 
   private createPolicyMacroStack(): cfn.CfnStack {
@@ -171,18 +181,17 @@ export class DatadogIntegration extends Construct {
   private createForwarderStack(
     props: DatadogIntegrationConfigWithDefaults,
   ): cfn.CfnStack {
-    return new cfn.CfnStack(this, 'ForwarderStack', {
-      templateUrl: `https://datadog-cloudformation-template.s3.amazonaws.com/aws/forwarder/${props.forwarderVersion}.yaml`,
-      parameters: Object.assign(
-        {
-          DdApiKey: 'USE_ARN',
-          DdApiKeySecretArn: props.apiKey.secretArn,
-          DdSite: props.site,
-          FunctionName: props.forwarderName,
-        },
-        { ...props.additionalForwarderParams },
-      ),
-    });
+
+    return new forwarder.ForwarderStack(this, 'ForwarderStack', {
+      forwarderVersion: props.forwarderVersion,
+      templateParameters: {
+        DdApiKey: 'USE_ARN',
+        DdApiKeySecretArn: props.apiKey.secretArn,
+        DdSite: props.site,
+        FunctionName: props.forwarderName,
+        ...props.additionalForwarderParams,
+      },
+    } );
   }
 }
 
@@ -200,3 +209,5 @@ export class DatadogIntegrationStack extends cdk.Stack {
     new DatadogIntegration(this, id, props);
   }
 }
+
+

test/index.test.ts

@@ -407,7 +407,7 @@ describe('DatadogIntegrationStack', () => {
         apiKey: secret,
         externalId: 'not-a-real-id',
         additionalForwarderParams: {
-          Foo: 'bar',
+          FunctionName: 'bar',
         },
       });
 
@@ -421,8 +421,7 @@ describe('DatadogIntegrationStack', () => {
             'Fn::ImportValue': 'Stack:ExportsOutputRefSecretA720EF052D953DED',
           },
           DdSite: 'datadoghq.com',
-          FunctionName: 'DatadogForwarder',
-          Foo: 'bar', // the sub-assert
+          FunctionName: 'bar',
         },
       });
     });