feat(appsync): support custom domain mappings

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

@@ -285,6 +285,43 @@ ds.createResolver({
 });
 ```
 
+## Custom Domain Names
+
+For many use cases you may want to associate a custom domain name with your
+GraphQL API. This can be done during the API creation.
+
+```ts
+import * as acm from '@aws-cdk/aws-certificatemanager';
+import * as route53 from '@aws-cdk/aws-route53';
+
+const myDomainName = 'api.example.com';
+const certificate = new acm.Certificate(this, 'cert', { domainName: myDomainName });
+const api = new appsync.GraphqlApi(this, 'api', {
+  name: 'myApi',
+  domainName: {
+    certificate,
+    domainName: myDomainName,
+  },
+});
+
+// hosted zone and route53 features
+declare const hostedZoneId: string;
+declare const zoneName = 'example.com';
+
+// hosted zone for adding appsync domain
+const zone = route53.HostedZone.fromHostedZoneAttributes(this, `HostedZone`, {
+  hostedZoneId,
+  zoneName,
+});
+
+// create a cname to the appsync domain. will map to something like xxxx.cloudfront.net
+new route53.CnameRecord(this, `CnameApiRecord`, {
+  recordName: 'api',
+  zone,
+  domainName: myDomainName,
+});
+```
+
 ## Schema
 
 Every GraphQL Api needs a schema to define the Api. CDK offers `appsync.Schema`

packages/@aws-cdk/aws-appsync/lib/graphqlapi.ts

@@ -1,9 +1,10 @@
+import { ICertificate } from '@aws-cdk/aws-certificatemanager';
 import { IUserPool } from '@aws-cdk/aws-cognito';
 import { ManagedPolicy, Role, IRole, ServicePrincipal, Grant, IGrantable } from '@aws-cdk/aws-iam';
 import { IFunction } from '@aws-cdk/aws-lambda';
 import { ArnFormat, CfnResource, Duration, Expiration, IResolvable, Stack } from '@aws-cdk/core';
 import { Construct } from 'constructs';
-import { CfnApiKey, CfnGraphQLApi, CfnGraphQLSchema } from './appsync.generated';
+import { CfnApiKey, CfnGraphQLApi, CfnGraphQLSchema, CfnDomainName, CfnDomainNameApiAssociation } from './appsync.generated';
 import { IGraphqlApi, GraphqlApiBase } from './graphqlapi-base';
 import { Schema } from './schema';
 import { IIntermediateType } from './schema-base';
@@ -254,6 +255,21 @@ export interface LogConfig {
   readonly role?: IRole;
 }
 
+/**
+ * Domain name configuration for AppSync
+ */
+export interface DomainOptions {
+  /**
+   * The certificate to use with the domain name.
+   */
+  readonly certificate: ICertificate;
+
+  /**
+   * The actual domain name. For example, `api.example.com`.
+   */
+  readonly domainName: string;
+}
+
 /**
  * Properties for an AppSync GraphQL API
  */
@@ -292,6 +308,16 @@ export interface GraphqlApiProps {
    * @default - false
    */
   readonly xrayEnabled?: boolean;
+
+  /**
+   * The domain name configuration for the GraphQL API
+   *
+   * The Route 53 hosted zone and CName DNS record must be configured in addition to this setting to
+   * enable custom domain URL
+   *
+   * @default - no domain name
+   */
+  readonly domainName?: DomainOptions;
 }
 
 /**
@@ -391,7 +417,7 @@ export class GraphqlApi extends GraphqlApiBase {
     class Import extends GraphqlApiBase {
       public readonly apiId = attrs.graphqlApiId;
       public readonly arn = arn;
-      constructor (s: Construct, i: string) {
+      constructor(s: Construct, i: string) {
         super(s, i);
       }
     }
@@ -450,7 +476,7 @@ export class GraphqlApi extends GraphqlApiBase {
     const additionalModes = props.authorizationConfig?.additionalAuthorizationModes ?? [];
     const modes = [defaultMode, ...additionalModes];
 
-    this.modes = modes.map((mode) => mode.authorizationType );
+    this.modes = modes.map((mode) => mode.authorizationType);
 
     this.validateAuthorizationProps(modes);
 
@@ -472,6 +498,19 @@ export class GraphqlApi extends GraphqlApiBase {
     this.schema = props.schema ?? new Schema();
     this.schemaResource = this.schema.bind(this);
 
+    if (props.domainName) {
+      new CfnDomainName(this, 'DomainName', {
+        domainName: props.domainName.domainName,
+        certificateArn: props.domainName.certificate.certificateArn,
+        description: `domain for ${this.name} at ${this.graphqlUrl}`,
+      });
+
+      new CfnDomainNameApiAssociation(this, 'DomainAssociation', {
+        domainName: props.domainName.domainName,
+        apiId: this.apiId,
+      });
+    }
+
     if (modes.some((mode) => mode.authorizationType === AuthorizationType.API_KEY)) {
       const config = modes.find((mode: AuthorizationMode) => {
         return mode.authorizationType === AuthorizationType.API_KEY && mode.apiKeyConfig;

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

@@ -89,6 +89,7 @@
     "jest": "^27.5.1"
   },
   "dependencies": {
+    "@aws-cdk/aws-certificatemanager": "0.0.0",
     "@aws-cdk/aws-cognito": "0.0.0",
     "@aws-cdk/aws-dynamodb": "0.0.0",
     "@aws-cdk/aws-ec2": "0.0.0",
@@ -104,6 +105,7 @@
   },
   "homepage": "https://github.com/aws/aws-cdk",
   "peerDependencies": {
+    "@aws-cdk/aws-certificatemanager": "0.0.0",
     "@aws-cdk/aws-cognito": "0.0.0",
     "@aws-cdk/aws-dynamodb": "0.0.0",
     "@aws-cdk/aws-ec2": "0.0.0",

packages/@aws-cdk/aws-appsync/test/appsync.test.ts

@@ -1,5 +1,6 @@
 import * as path from 'path';
 import { Template } from '@aws-cdk/assertions';
+import { Certificate } from '@aws-cdk/aws-certificatemanager';
 import * as iam from '@aws-cdk/aws-iam';
 import * as cdk from '@aws-cdk/core';
 import * as appsync from '../lib';
@@ -155,3 +156,38 @@ test('appsync GraphqlApi should not use custom role for CW Logs when not specifi
     },
   });
 });
+
+test('appsync GraphqlApi should be configured with custom domain when specified', () => {
+  const domainName = 'api.example.com';
+  // GIVEN
+  const certificate = new Certificate(stack, 'AcmCertificate', {
+    domainName,
+  });
+
+  // WHEN
+  new appsync.GraphqlApi(stack, 'api-custom-cw-logs-role', {
+    authorizationConfig: {},
+    name: 'apiWithCustomRole',
+    schema: appsync.Schema.fromAsset(path.join(__dirname, 'appsync.test.graphql')),
+    domainName: {
+      domainName,
+      certificate,
+    },
+  });
+
+  // THEN
+  Template.fromStack(stack).hasResourceProperties('AWS::AppSync::DomainNameApiAssociation', {
+    ApiId: {
+      'Fn::GetAtt': [
+        'apicustomcwlogsrole508EAC74',
+        'ApiId',
+      ],
+    },
+    DomainName: domainName,
+  });
+
+  Template.fromStack(stack).hasResourceProperties('AWS::AppSync::DomainName', {
+    CertificateArn: { Ref: 'AcmCertificate49D3B5AF' },
+    DomainName: domainName,
+  });
+});