fix(appsync): domain name api association fails when domain name crea…

…tion is in the same stack (#20173)

Fixes #18395 and other issues where defining domain name in `aws-appsync-alpha` will fail because domain name is not created before the domain name association.

----

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### New Features

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

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

@@ -494,16 +494,18 @@ export class GraphqlApi extends GraphqlApiBase {
     this.schemaResource = this.schema.bind(this);
 
     if (props.domainName) {
-      new CfnDomainName(this, 'DomainName', {
+      const 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', {
+      const domainNameAssociation = new CfnDomainNameApiAssociation(this, 'DomainAssociation', {
         domainName: props.domainName.domainName,
         apiId: this.apiId,
       });
+
+      domainNameAssociation.addDependsOn(domainName);
     }
 
     if (modes.some((mode) => mode.authorizationType === AuthorizationType.API_KEY)) {

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

@@ -0,0 +1,43 @@
+import * as path from 'path';
+import { Template } from '@aws-cdk/assertions';
+import * as acm from '@aws-cdk/aws-certificatemanager';
+import { Certificate } from '@aws-cdk/aws-certificatemanager';
+import * as cdk from '@aws-cdk/core';
+import * as appsync from '../lib';
+
+// GLOBAL GIVEN
+let stack: cdk.Stack;
+let certificate: acm.Certificate;
+
+beforeEach(() => {
+  stack = new cdk.Stack();
+  certificate = new Certificate(stack, 'certificate', {
+    domainName: 'aws.amazon.com',
+  });
+});
+
+describe('Tests of AppSync Domain Name', () => {
+  test('DomainNameAssociation depends on DomainName construct', () => {
+    new appsync.GraphqlApi(stack, 'baseApi', {
+      name: 'api',
+      schema: appsync.Schema.fromAsset(
+        path.join(__dirname, 'appsync.test.graphql'),
+      ),
+      domainName: {
+        certificate,
+        domainName: 'aws.amazon.com',
+      },
+    });
+
+    const domainName = Template.fromStack(stack).findResources(
+      'AWS::AppSync::DomainName',
+    );
+
+    Template.fromStack(stack).hasResource(
+      'AWS::AppSync::DomainNameApiAssociation',
+      {
+        DependsOn: [Object.keys(domainName)[0]],
+      },
+    );
+  });
+});