feat(apigateway): import API keys (#9155)

add fromApiKeyId import method to the ApiKey construct

closes #8367

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: corymhall

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

@@ -200,6 +200,12 @@ const key = api.addApiKey('ApiKey', {
 });
 ```
 
+Existing API keys can also be imported into a CDK app using its id.
+
+```ts
+const importedKey = ApiKey.fromApiKeyId(this, 'imported-key', '<api-key-id>');
+```
+
 In scenarios where you need to create a single api key and configure rate limiting for it, you can use `RateLimitedApiKey`.
 This construct lets you specify rate limiting properties which should be applied only to the api key being created.
 The API key created has the specified rate limits, such as quota and throttles, applied.

packages/@aws-cdk/aws-apigateway/lib/api-key.ts

@@ -81,6 +81,18 @@ export interface ApiKeyProps extends ApiKeyOptions {
  * for Method resources that require an Api Key.
  */
 export class ApiKey extends Resource implements IApiKey {
+
+  /**
+   * Import an ApiKey by its Id
+   */
+  public static fromApiKeyId(scope: Construct, id: string, apiKeyId: string): IApiKey {
+    class Import extends Resource implements IApiKey {
+      public keyId = apiKeyId;
+    }
+
+    return new Import(scope, id);
+  }
+
   public readonly keyId: string;
 
   constructor(scope: Construct, id: string, props: ApiKeyProps = { }) {

packages/@aws-cdk/aws-apigateway/package.json

@@ -115,7 +115,6 @@
       "from-method:@aws-cdk/aws-apigateway.Resource",
       "duration-prop-type:@aws-cdk/aws-apigateway.QuotaSettings.period",
       "duration-prop-type:@aws-cdk/aws-apigateway.ResponseType.INTEGRATION_TIMEOUT",
-      "from-method:@aws-cdk/aws-apigateway.ApiKey",
       "ref-via-interface:@aws-cdk/aws-apigateway.ApiKeyProps.resources",
       "props-physical-name:@aws-cdk/aws-apigateway.DeploymentProps",
       "props-physical-name:@aws-cdk/aws-apigateway.MethodProps",

packages/@aws-cdk/aws-apigateway/test/test.api-key.ts

@@ -1,4 +1,4 @@
-import { expect, haveResource, ResourcePart } from '@aws-cdk/assert';
+import { expect, haveResource, haveResourceLike, ResourcePart } from '@aws-cdk/assert';
 import * as cdk from '@aws-cdk/core';
 import { Test } from 'nodeunit';
 import * as apigateway from '../lib';
@@ -43,4 +43,27 @@ export = {
 
     test.done();
   },
+
+  'use an imported api key'(test: Test) {
+    // GIVEN
+    const stack = new cdk.Stack();
+    const api = new apigateway.RestApi(stack, 'test-api', { cloudWatchRole: false, deploy: true, deployOptions: { stageName: 'test' } });
+    api.root.addMethod('GET'); // api must have atleast one method.
+
+    // WHEN
+    const importedKey = apigateway.ApiKey.fromApiKeyId(stack, 'imported', 'KeyIdabc');
+    api.addUsagePlan('plan', {
+      apiKey: importedKey,
+    });
+
+    // THEN
+    expect(stack).to(haveResourceLike('AWS::ApiGateway::UsagePlanKey', {
+      KeyId: 'KeyIdabc',
+      KeyType: 'API_KEY',
+      UsagePlanId: {
+        Ref: 'testapiplan1B111AFF',
+      },
+    }));
+    test.done();
+  },
 };