feat(amplify): Add Amplify asset deployment resource

This change adds a custom resource that allows users
to publish S3 assets to AWS Amplify.

fixes aws#16208

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

@@ -208,3 +208,14 @@ const amplifyApp = new amplify.App(stack, 'App', {
   ],
 });
 ```
+
+## Deploying Assets
+
+`sourceCodeProvider` is optional; when this is not specified the Amplify app can be deployed to using `.zip` packages. The `AmplifyAssetDeployment` construct can be used to deploy S3 assets to Amplify as part of the CDK:
+
+```ts
+const asset = new assets.Asset(this, "SampleAsset", {});
+const amplifyApp = new amplify.App(this, 'MyApp', {});
+const branch = amplifyApp.addBranch("dev");
+branch.addAssetDeployment(asset);
+```

packages/@aws-cdk/aws-amplify/lib/asset-deployment-handler/common.ts

@@ -0,0 +1,76 @@
+export interface AmplifyJobId {
+  /**
+   * If this field is included in an event passed to "IsComplete", it means we
+   * initiated an Amplify deployment that should be monitored using
+   * amplify:GetJob
+   */
+  AmplifyJobId?: string;
+}
+
+export type ResourceEvent = AWSLambda.CloudFormationCustomResourceEvent & AmplifyJobId;
+
+export interface IsCompleteResponse {
+  /**
+   * Indicates if the resource operation is complete or should we retry.
+   */
+  readonly IsComplete: boolean;
+
+  /**
+   * Additional/changes to resource attributes.
+   */
+  readonly Data?: { [name: string]: any };
+};
+
+export abstract class ResourceHandler {
+  protected readonly requestId: string;
+  protected readonly logicalResourceId: string;
+  protected readonly requestType: 'Create' | 'Update' | 'Delete';
+  protected readonly physicalResourceId?: string;
+  protected readonly event: ResourceEvent;
+
+  constructor(event: ResourceEvent) {
+    this.requestType = event.RequestType;
+    this.requestId = event.RequestId;
+    this.logicalResourceId = event.LogicalResourceId;
+    this.physicalResourceId = (event as any).PhysicalResourceId;
+    this.event = event;
+  }
+
+  public onEvent() {
+    switch (this.requestType) {
+      case 'Create':
+        return this.onCreate();
+      case 'Update':
+        return this.onUpdate();
+      case 'Delete':
+        return this.onDelete();
+    }
+
+    throw new Error(`Invalid request type ${this.requestType}`);
+  }
+
+  public isComplete() {
+    switch (this.requestType) {
+      case 'Create':
+        return this.isCreateComplete();
+      case 'Update':
+        return this.isUpdateComplete();
+      case 'Delete':
+        return this.isDeleteComplete();
+    }
+
+    throw new Error(`Invalid request type ${this.requestType}`);
+  }
+
+  protected log(x: any) {
+    // eslint-disable-next-line no-console
+    console.log(JSON.stringify(x, undefined, 2));
+  }
+
+  protected abstract async onCreate(): Promise<AmplifyJobId>;
+  protected abstract async onDelete(): Promise<void>;
+  protected abstract async onUpdate(): Promise<AmplifyJobId>;
+  protected abstract async isCreateComplete(): Promise<IsCompleteResponse>;
+  protected abstract async isDeleteComplete(): Promise<IsCompleteResponse>;
+  protected abstract async isUpdateComplete(): Promise<IsCompleteResponse>;
+}

packages/@aws-cdk/aws-amplify/lib/asset-deployment-handler/handler.ts

@@ -0,0 +1,136 @@
+// aws-sdk available at runtime for lambdas
+// eslint-disable-next-line import/no-extraneous-dependencies
+import { Amplify, S3 } from 'aws-sdk';
+import { AmplifyJobId, IsCompleteResponse, ResourceEvent, ResourceHandler } from './common';
+
+export interface AmplifyAssetDeploymentProps {
+  AppId: string;
+  BranchName: string;
+  S3BucketName: string;
+  S3ObjectKey: string;
+  TimeoutSeconds: number;
+}
+
+export class AmplifyAssetDeploymentHandler extends ResourceHandler {
+  private readonly props: AmplifyAssetDeploymentProps;
+  protected readonly amplify: Amplify;
+  protected readonly s3: S3;
+
+  constructor(amplify: Amplify, s3: S3, event: ResourceEvent) {
+    super(event);
+
+    this.props = parseProps(this.event.ResourceProperties);
+    this.amplify = amplify;
+    this.s3 = s3;
+  }
+
+  // ------
+  // CREATE
+  // ------
+
+  protected async onCreate(): Promise<AmplifyJobId> {
+    // eslint-disable-next-line no-console
+    console.log('deploying to Amplify with options:', JSON.stringify(this.props, undefined, 2));
+
+    // Verify no jobs are currently running.
+    const jobs = await this.amplify
+      .listJobs({
+        appId: this.props.AppId,
+        branchName: this.props.BranchName,
+        maxResults: 1,
+      })
+      .promise();
+
+    if (
+      jobs.jobSummaries &&
+      jobs.jobSummaries.find(summary => summary.status === 'PENDING')
+    ) {
+      return Promise.reject('Amplify job already running. Aborting deployment.');
+    }
+
+    // Create a pre-signed get URL of the asset so Amplify can retrieve it.
+    const assetUrl = this.s3.getSignedUrl('getObject', {
+      Bucket: this.props.S3BucketName,
+      Key: this.props.S3ObjectKey,
+    });
+
+    // Deploy the asset to Amplify.
+    const deployment = await this.amplify
+      .startDeployment({
+        appId: this.props.AppId,
+        branchName: this.props.BranchName,
+        sourceUrl: assetUrl,
+      })
+      .promise();
+
+    return {
+      AmplifyJobId: deployment.jobSummary.jobId,
+    };
+  }
+
+  protected async isCreateComplete() {
+    return this.isActive(this.event.AmplifyJobId);
+  }
+
+  // ------
+  // DELETE
+  // ------
+
+  protected async onDelete(): Promise<void> {
+    // We can't delete this resource as it's a deployment.
+    return;
+  }
+
+  protected async isDeleteComplete(): Promise<IsCompleteResponse> {
+    // We can't delete this resource as it's a deployment.
+    return {
+      IsComplete: true,
+    };
+  }
+
+  // ------
+  // UPDATE
+  // ------
+
+  protected async onUpdate() {
+    return this.onCreate();
+  }
+
+  protected async isUpdateComplete() {
+    return this.isActive(this.event.AmplifyJobId);
+  }
+
+  private async isActive(jobId?: string): Promise<IsCompleteResponse> {
+    if (!jobId) {
+      throw new Error('Unable to determine Amplify job status without job id');
+    }
+
+    const job = await this.amplify
+      .getJob({
+        appId: this.props.AppId,
+        branchName: this.props.BranchName,
+        jobId: jobId,
+      })
+      .promise();
+
+    if (job.job.summary.status === 'SUCCEED') {
+      return {
+        IsComplete: true,
+        Data: {
+          JobId: jobId,
+          Status: job.job.summary.status,
+        },
+      };
+    } if (job.job.summary.status === 'FAILED' || job.job.summary.status === 'CANCELLED') {
+      throw new Error(`Amplify job failed with status: ${job.job.summary.status}`);
+    } else {
+      return {
+        IsComplete: false,
+      };
+    }
+  }
+}
+
+function parseProps(props: any): AmplifyAssetDeploymentProps {
+  return props;
+}

packages/@aws-cdk/aws-amplify/lib/asset-deployment-handler/index.ts

@@ -0,0 +1,35 @@
+// eslint-disable-next-line import/no-extraneous-dependencies
+import { IsCompleteResponse } from '@aws-cdk/custom-resources/lib/provider-framework/types';
+// aws-sdk available at runtime for lambdas
+// eslint-disable-next-line import/no-extraneous-dependencies
+import { Amplify, S3, config } from 'aws-sdk';
+import { ResourceEvent } from './common';
+import { AmplifyAssetDeploymentHandler } from './handler';
+
+const AMPLIFY_ASSET_DEPLOYMENT_RESOURCE_TYPE = 'Custom::AmplifyAssetDeployment';
+
+config.logger = console;
+
+const amplify = new Amplify();
+const s3 = new S3({ signatureVersion: 'v4' });
+
+export async function onEvent(event: ResourceEvent) {
+  const provider = createResourceHandler(event);
+  return provider.onEvent();
+}
+
+export async function isComplete(
+  event: ResourceEvent,
+): Promise<IsCompleteResponse> {
+  const provider = createResourceHandler(event);
+  return provider.isComplete();
+}
+
+function createResourceHandler(event: ResourceEvent) {
+  switch (event.ResourceType) {
+    case AMPLIFY_ASSET_DEPLOYMENT_RESOURCE_TYPE:
+      return new AmplifyAssetDeploymentHandler(amplify, s3, event);
+    default:
+      throw new Error(`Unsupported resource type "${event.ResourceType}"`);
+  }
+}

packages/@aws-cdk/aws-amplify/lib/branch.ts

@@ -1,5 +1,19 @@
+import * as path from 'path';
 import * as codebuild from '@aws-cdk/aws-codebuild';
-import { IResource, Lazy, Resource } from '@aws-cdk/core';
+import * as iam from '@aws-cdk/aws-iam';
+import * as lambda from '@aws-cdk/aws-lambda';
+import { NodejsFunction } from '@aws-cdk/aws-lambda-nodejs';
+import { Asset } from '@aws-cdk/aws-s3-assets';
+import {
+  CustomResource,
+  IResource,
+  Lazy,
+  Resource,
+  Duration,
+  NestedStack,
+  Stack,
+} from '@aws-cdk/core';
+import { Provider } from '@aws-cdk/custom-resources';
 import { Construct } from 'constructs';
 import { CfnBranch } from './amplify.generated';
 import { IApp } from './app';
@@ -125,6 +139,8 @@ export class Branch extends Resource implements IBranch {
 
   public readonly branchName: string;
 
+  private readonly appId: string;
+
   private readonly environmentVariables: { [name: string]: string };
 
   constructor(scope: Construct, id: string, props: BranchProps) {
@@ -148,6 +164,7 @@ export class Branch extends Resource implements IBranch {
 
     this.arn = branch.attrArn;
     this.branchName = branch.attrBranchName;
+    this.appId = props.app.appId;
   }
 
   /**
@@ -160,4 +177,96 @@ export class Branch extends Resource implements IBranch {
     this.environmentVariables[name] = value;
     return this;
   }
+
+  /**
+   * Allows deployment of S3 assets to Amplify via a custom resource.
+   *
+   * The Amplify app must not have a sourceCodeProvider configured as this resource uses Amplify's
+   * startDeployment API to initiate and deploy a S3 asset onto the App.
+   */
+  public addAssetDeployment(asset: Asset) {
+    new CustomResource(this, 'DeploymentResource', {
+      serviceToken: AmplifyAssetDeploymentProvider.getOrCreate(this),
+      resourceType: 'Custom::AmplifyAssetDeployment',
+      properties: {
+        AppId: this.appId,
+        BranchName: this.branchName,
+        S3ObjectKey: asset.s3ObjectKey,
+        S3BucketName: asset.s3BucketName,
+      },
+    });
+  }
+}
+
+class AmplifyAssetDeploymentProvider extends NestedStack {
+  /**
+   * Returns the singleton provider.
+   */
+  public static getOrCreate(scope: Construct) {
+    const providerId =
+      'com.amazonaws.cdk.custom-resources.amplify-asset-deployment-provider';
+    const stack = Stack.of(scope);
+    const group =
+      (stack.node.tryFindChild(providerId) as AmplifyAssetDeploymentProvider) ?? new AmplifyAssetDeploymentProvider(stack, providerId);
+    return group.provider.serviceToken;
+  }
+
+  private readonly provider: Provider;
+
+  constructor(scope: Construct, id: string) {
+    super(scope, id);
+
+    const onEvent = new NodejsFunction(
+      this,
+      'amplify-asset-deployment-on-event',
+      {
+        entry: path.join(
+          __dirname,
+          'asset-deployment-handler/index.ts',
+        ),
+        runtime: lambda.Runtime.NODEJS_14_X,
+        handler: 'onEvent',
+        initialPolicy: [
+          new iam.PolicyStatement({
+            resources: ['*'],
+            actions: [
+              's3:GetObject',
+              's3:GetSignedUrl',
+              'amplify:ListJobs',
+              'amplify:StartDeployment',
+            ],
+          }),
+        ],
+      },
+    );
+
+    const isComplete = new NodejsFunction(
+      this,
+      'amplify-asset-deployment-is-complete',
+      {
+        entry: path.join(
+          __dirname,
+          'asset-deployment-handler/index.ts',
+        ),
+        runtime: lambda.Runtime.NODEJS_14_X,
+        handler: 'isComplete',
+        initialPolicy: [
+          new iam.PolicyStatement({
+            resources: ['*'],
+            actions: ['amplify:GetJob*'],
+          }),
+        ],
+      },
+    );
+
+    this.provider = new Provider(
+      this,
+      'amplify-asset-deployment-handler-provider',
+      {
+        onEventHandler: onEvent,
+        isCompleteHandler: isComplete,
+        totalTimeout: Duration.minutes(5),
+      },
+    );
+  }
 }