feat(aws-s3objectlambda): add L2 construct for S3 Object Lambda

packages/@aws-cdk/aws-s3objectlambda/README.md

@@ -9,6 +9,14 @@
 >
 > [CFN Resources]: https://docs.aws.amazon.com/cdk/latest/guide/constructs.html#constructs_lib
 
+![cdk-constructs: Experimental](https://img.shields.io/badge/cdk--constructs-experimental-important.svg?style=for-the-badge)
+
+> The APIs of higher level constructs in this module are experimental and under active development.
+> They are subject to non-backward compatible changes or removal in any future version. These are
+> not subject to the [Semantic Versioning](https://semver.org/) model and breaking changes will be
+> announced in the release notes. This means that while you may use them, you may need to update
+> your source code when upgrading to a newer version of this package.
+
 ---
 
 <!--END STABILITY BANNER-->

packages/@aws-cdk/aws-s3objectlambda/lib/index.ts

@@ -1,2 +1,4 @@
+export * from './object-lambda';
+
 // AWS::S3ObjectLambda CloudFormation Resources:
 export * from './s3objectlambda.generated';

packages/@aws-cdk/aws-s3objectlambda/lib/object-lambda.ts

@@ -0,0 +1,166 @@
+import * as iam from '@aws-cdk/aws-iam';
+import * as lambda from '@aws-cdk/aws-lambda';
+import * as s3 from '@aws-cdk/aws-s3';
+import { Stack } from '@aws-cdk/core';
+import { Construct } from 'constructs';
+import { CfnAccessPoint } from './s3objectlambda.generated';
+
+// keep this import separate from other imports to reduce chance for merge conflicts with v2-main
+// eslint-disable-next-line no-duplicate-imports, import/order
+import { Construct as CoreConstruct } from '@aws-cdk/core';
+
+/**
+ * Creates an S3 Object Lambda, which can intercept and transform
+ * `GetObject` requests.
+ *
+ * @param fn The Lambda function
+ * @param props Configuration for this Object Lambda
+ */
+export interface ObjectLambdaProps {
+ /**
+ * The bucket to which this Object Lambda belongs
+ */
+ readonly bucket: s3.IBucket
+
+ /**
+ * The Lambda function used to transform objects.
+ */
+ readonly fn: lambda.IFunction
+
+ /**
+ * The name of the Object Lambda access point.
+ */
+ readonly name: string
+
+ /**
+ * Whether CloudWatch metrics are enabled for the Object Lambda.
+ *
+ * @default false
+ */
+ readonly cloudWatchMetricsEnabled?: boolean
+
+ /**
+ * Whether the Lambda function can process `GetObject-Range` requests.
+ *
+ * @default false
+ */
+ readonly supportsGetObjectRange?: boolean
+
+ /**
+ * Whether the Lambda function can process `GetObject-PartNumber` requests.
+ *
+ * @default false
+ */
+ readonly supportsGetObjectPartNumber?: boolean
+
+ /**
+ * Additional JSON that provides supplemental data passed to the
+ * Lambda function on every request.
+ *
+ * @default - No data.
+ */
+ readonly payload?: string
+}
+
+/**
+ * An S3 Object Lambda for intercepting and transforming `GetObject` requests.
+ */
+export class ObjectLambda extends CoreConstruct {
+ private readonly objectLambda: CfnAccessPoint
+ private readonly stack: Stack
+
+ constructor(scope: Construct, id: string, props: ObjectLambdaProps) {
+ super(scope, id);
+
+ this.stack = props.bucket.stack;
+
+ const supporting = new s3.CfnAccessPoint(this, 'AccessPoint', {
+ bucket: props.bucket.bucketName,
+ // TODO: configure publicAccessBlockConfiguration?
+ });
+ supporting.addPropertyOverride('Name', `${props.name}-access-point`);
+
+ const allowedFeatures = [];
+ if (props.supportsGetObjectPartNumber) {
+ allowedFeatures.push('GetObject-PartNumber');
+ }
+ if (props.supportsGetObjectRange) {
+ allowedFeatures.push('GetObject-Range');
+ }
+
+ this.objectLambda = new CfnAccessPoint(this, 'LambdaAccessPoint', {
+ name: props.name.toLowerCase(),
+ objectLambdaConfiguration: {
+ allowedFeatures,
+ cloudWatchMetricsEnabled: props.cloudWatchMetricsEnabled,
+ supportingAccessPoint: supporting.getAtt('Arn').toString(),
+ transformationConfigurations: [
+ {
+ actions: ['GetObject'],
+ contentTransformation: {
+ AwsLambda: {
+ FunctionArn: props.fn.functionArn,
+ FunctionPayload: props.payload ?? '',
+ },
+ },
+ },
+ ],
+ },
+ });
+ this.objectLambda.addDependsOn(supporting);
+
+ props.fn.addToRolePolicy(
+ new iam.PolicyStatement({
+ actions: ['s3-object-lambda:WriteGetObjectResponse'],
+ resources: ['*'],
+ }),
+ );
+ }
+
+ /**
+ * The ARN of the Object Lambda access point.
+ */
+ get arn(): string {
+ return this.objectLambda.getAtt('Arn').toString();
+ }
+
+ /**
+ * The IPv4 DNS name of the Object Lambda access point.
+ */
+ get domainName(): string {
+ const urlSuffix = this.stack.urlSuffix;
+ return `${this.objectLambda.name}-${this.stack.account}.s3.${urlSuffix}`;
+ }
+
+ /**
+ * The regional domain name of the Object Lambda access point.
+ */
+ get regionalDomainName(): string {
+ const urlSuffix = this.stack.urlSuffix;
+ const region = this.stack.region;
+ return `${this.objectLambda.name}-${this.stack.account}.s3.${region}.${urlSuffix}`;
+ }
+
+ /**
+ * The virtual hosted-style URL of an S3 object through this access point.
+ * Specify `regional: false` at the options for non-regional URL.
+ * @param key The S3 key of the object. If not specified, the URL of the
+ * bucket is returned.
+ * @param options Options for generating URL.
+ * @returns an ObjectS3Url token
+ */
+ public virtualHostedUrlForObject(key?: string, options?: s3.VirtualHostedStyleUrlOptions): string {
+ const domainName = options?.regional ?? true ? this.regionalDomainName : this.domainName;
+ const prefix = `https://${domainName}`;
+ if (typeof key !== 'string') {
+ return prefix;
+ }
+ if (key.startsWith('/')) {
+ key = key.slice(1);
+ }
+ if (key.endsWith('/')) {
+ key = key.slice(0, -1);
+ }
+ return `${prefix}/${key}`;
+ }
+}

packages/@aws-cdk/aws-s3objectlambda/package.json

@@ -79,21 +79,31 @@
  "devDependencies": {
  "@types/jest": "^26.0.24",
  "cdk-build-tools": "0.0.0",
+ "cdk-integ-tools": "0.0.0",
  "cfn2ts": "0.0.0",
+ "jest": "^26.6.3",
  "pkglint": "0.0.0",
  "@aws-cdk/assert-internal": "0.0.0"
  },
  "dependencies": {
- "@aws-cdk/core": "0.0.0"
+ "@aws-cdk/aws-iam": "0.0.0",
+ "@aws-cdk/aws-lambda": "0.0.0",
+ "@aws-cdk/aws-s3": "0.0.0",
+ "@aws-cdk/core": "0.0.0",
+ "constructs": "^3.3.69"
  },
  "peerDependencies": {
- "@aws-cdk/core": "0.0.0"
+ "@aws-cdk/aws-iam": "0.0.0",
+ "@aws-cdk/aws-lambda": "0.0.0",
+ "@aws-cdk/aws-s3": "0.0.0",
+ "@aws-cdk/core": "0.0.0",
+ "constructs": "^3.3.69"
  },
  "engines": {
  "node": ">= 10.13.0 <13 || >=13.7.0"
  },
  "stability": "experimental",
- "maturity": "cfn-only",
+ "maturity": "experimental",
  "awscdkio": {
  "announce": false
  },