@aws-cdk/aws-s3

What is @aws-cdk/aws-s3?

@aws-cdk/aws-s3 is an AWS Cloud Development Kit (CDK) library that allows you to define Amazon S3 buckets and related resources using code. This package provides a high-level, object-oriented abstraction to create and manage S3 buckets, configure bucket policies, set up event notifications, and more.

What are @aws-cdk/aws-s3's main functionalities?

Create an S3 Bucket

This code sample demonstrates how to create a versioned S3 bucket with a removal policy that destroys the bucket when the stack is deleted.

const s3 = require('@aws-cdk/aws-s3');
const cdk = require('@aws-cdk/core');

class MyStack extends cdk.Stack {
  constructor(scope, id, props) {
    super(scope, id, props);

    new s3.Bucket(this, 'MyFirstBucket', {
      versioned: true,
      removalPolicy: cdk.RemovalPolicy.DESTROY,
    });
  }
}

const app = new cdk.App();
new MyStack(app, 'MyStack');

Add Bucket Policy

This code sample shows how to add a bucket policy to an S3 bucket, allowing any principal to perform the 's3:GetObject' action on all objects in the bucket.

const s3 = require('@aws-cdk/aws-s3');
const cdk = require('@aws-cdk/core');

class MyStack extends cdk.Stack {
  constructor(scope, id, props) {
    super(scope, id, props);

    const bucket = new s3.Bucket(this, 'MyBucket');

    bucket.addToResourcePolicy(new cdk.aws_iam.PolicyStatement({
      actions: ['s3:GetObject'],
      resources: [bucket.arnForObjects('*')],
      principals: [new cdk.aws_iam.AnyPrincipal()],
    }));
  }
}

const app = new cdk.App();
new MyStack(app, 'MyStack');

Enable Event Notifications

This code sample demonstrates how to enable event notifications for an S3 bucket. It sets up a notification to an SNS topic whenever an object is created in the bucket.

const s3 = require('@aws-cdk/aws-s3');
const cdk = require('@aws-cdk/core');
const sns = require('@aws-cdk/aws-sns');
const s3n = require('@aws-cdk/aws-s3-notifications');

class MyStack extends cdk.Stack {
  constructor(scope, id, props) {
    super(scope, id, props);

    const bucket = new s3.Bucket(this, 'MyBucket');
    const topic = new sns.Topic(this, 'MyTopic');

    bucket.addEventNotification(s3.EventType.OBJECT_CREATED, new s3n.SnsDestination(topic));
  }
}

const app = new cdk.App();
new MyStack(app, 'MyStack');

Other packages similar to @aws-cdk/aws-s3

aws-sdk

The aws-sdk package is the official AWS SDK for JavaScript, which provides low-level APIs for interacting with AWS services, including S3. Unlike @aws-cdk/aws-s3, which is used for defining infrastructure as code, aws-sdk is used for making API calls to AWS services at runtime.

serverless

The serverless package is a framework for building and deploying serverless applications on AWS and other cloud providers. It allows you to define S3 buckets and other resources in a serverless.yml configuration file. While it provides similar functionalities, it is more focused on serverless architectures and deployments.

terraform

Terraform is an open-source infrastructure as code software tool that provides a consistent CLI workflow to manage hundreds of cloud services. It allows you to define S3 buckets and other AWS resources using HashiCorp Configuration Language (HCL). Terraform is cloud-agnostic and can manage resources across multiple cloud providers.

README

AWS S3 Construct Library

Define an unencrypted S3 bucket.

new Bucket(this, 'MyFirstBucket');

Bucket constructs expose the following deploy-time attributes:

• bucketArn - the ARN of the bucket (i.e. arn:aws:s3:::bucket_name)
• bucketName - the name of the bucket (i.e. bucket_name)
• bucketUrl - the URL of the bucket (i.e. https://s3.us-west-1.amazonaws.com/onlybucket)
• arnForObjects(...pattern) - the ARN of an object or objects within the bucket (i.e. arn:aws:s3:::my_corporate_bucket/exampleobject.png or arn:aws:s3:::my_corporate_bucket/Development/*)
• urlForObject(key) - the URL of an object within the bucket (i.e. https://s3.cn-north-1.amazonaws.com.cn/china-bucket/mykey)

Encryption

Define a KMS-encrypted bucket:

const bucket = new Bucket(this, 'MyUnencryptedBucket', {
    encryption: BucketEncryption.Kms
});

// you can access the encryption key:
assert(bucket.encryptionKey instanceof kms.EncryptionKey);

You can also supply your own key:

const myKmsKey = new kms.EncryptionKey(this, 'MyKey');

const bucket = new Bucket(this, 'MyEncryptedBucket', {
    encryption: BucketEncryption.Kms,
    encryptionKey: myKmsKey
});

assert(bucket.encryptionKey === myKmsKey);

Use BucketEncryption.ManagedKms to use the S3 master KMS key:

const bucket = new Bucket(this, 'Buck', {
    encryption: BucketEncryption.ManagedKms
});

assert(bucket.encryptionKey == null);

Permissions

A bucket policy will be automatically created for the bucket upon the first call to addToResourcePolicy(statement):

const bucket = new Bucket(this, 'MyBucket');
bucket.addToResourcePolicy(new iam.PolicyStatement()
    .addActions('s3:GetObject')
    .addAllResources());

Most of the time, you won't have to manipulate the bucket policy directly. Instead, buckets have "grant" methods called to give prepackaged sets of permissions to other resources. For example:

const lambda = new lambda.Function(this, 'Lambda', { /* ... */ });

const bucket = new Bucket(this, 'MyBucket');
bucket.grantReadWrite(lambda.role);

Will give the Lambda's execution role permissions to read and write from the bucket.

Buckets as sources in CodePipeline

This package also defines an Action that allows you to use a Bucket as a source in CodePipeline:

import codepipeline = require('@aws-cdk/aws-codepipeline');
import s3 = require('@aws-cdk/aws-s3');

const sourceBucket = new s3.Bucket(this, 'MyBucket', {
    versioned: true, // a Bucket used as a source in CodePipeline must be versioned
});

const pipeline = new codepipeline.Pipeline(this, 'MyPipeline');
const sourceStage = pipeline.addStage('Source');
const sourceAction = new s3.PipelineSourceAction(this, 'S3Source', {
    stage: sourceStage,
    bucket: sourceBucket,
    bucketKey: 'path/to/file.zip',
});

You can also add the Bucket to the Pipeline directly:

// equivalent to the code above:
const sourceAction = sourceBucket.addToPipeline(sourceStage, 'S3Source', {
    bucketKey: 'path/to/file.zip',
});

Importing and Exporting Buckets

You can create a Bucket construct that represents an external/existing/unowned bucket by using the Bucket.import factory method.

This method accepts an object that adheres to BucketRef which basically include tokens to bucket's attributes.

This means that you can define a BucketRef using token literals:

const bucket = Bucket.import(this, {
    bucketArn: new BucketArn('arn:aws:s3:::my-bucket')
});

// now you can just call methods on the bucket
bucket.grantReadWrite(user);

The bucket.export() method can be used to "export" the bucket from the current stack. It returns a BucketRef object that can later be used in a call to Bucket.import in another stack.

Here's an example.

Let's define a stack with an S3 bucket and export it using bucket.export().

class Producer extends Stack {
    public readonly myBucketRef: BucketRef;

    constructor(parent: App, name: string) {
        super(parent, name);

        const bucket = new Bucket(this, 'MyBucket');
        this.myBucketRef = bucket.export();
    }
}

Now let's define a stack that requires a BucketRef as an input and uses Bucket.import to create a Bucket object that represents this external bucket. Grant a user principal created within this consuming stack read/write permissions to this bucket and contents.

interface ConsumerProps {
    public userBucketRef: BucketRef;
}

class Consumer extends Stack {
    constructor(parent: App, name: string, props: ConsumerProps) {
        super(parent, name);

        const user = new User(this, 'MyUser');
        const userBucket = Bucket.import(this, props.userBucketRef);
        userBucket.grantReadWrite(user);
    }
}

Now, let's define our CDK app to bind these together:

const app = new App();

const producer = new Producer(app, 'produce');

new Consumer(app, 'consume', {
    userBucketRef: producer.myBucketRef
});

app.run();

Bucket Notifications

The Amazon S3 notification feature enables you to receive notifications when certain events happen in your bucket as described under S3 Bucket Notifications of the S3 Developer Guide.

To subscribe for bucket notifications, use the bucket.onEvent method. The bucket.onObjectCreated and bucket.onObjectRemoved can also be used for these common use cases.

The following example will subscribe an SNS topic to be notified of all ``s3:ObjectCreated:*` events:

const myTopic = new sns.Topic(this, 'MyTopic');
bucket.onEvent(s3.EventType.ObjectCreated, myTopic);

This call will also ensure that the topic policy can accept notifications for this specific bucket.

The following destinations are currently supported:

• sns.Topic
• sqs.Queue
• lambda.Function

It is also possible to specify S3 object key filters when subscribing. The following example will notify myQueue when objects prefixed with foo/ and have the .jpg suffix are removed from the bucket.

bucket.onEvent(s3.EventType.ObjectRemoved, myQueue, { prefix: 'foo/', suffix: '.jpg' });

Changelog

0.21.0 (2018-12-20)

Bug Fixes

• aws-cloudformation: change the type of Role in CodePipeline Actions to IRole. (#1364) (3d07e48), closes #1361
• codebuild: Rename includeBuildID property of S3BucketBuildArtifacts (#1354) (84eb7ad), closes #1347
• toolkit: scrutiny dialog should fail with no tty (#1382) (478a714), closes #1380

Features

• aws-codebuild: change the API of GitHub and BitBucket Sources. (#1345) (9cebf0d)
• add "engines.node" key to all packages (#1358) (b595cf0), closes #1337
• deprecate "cloudformation" namespace in favor of "CfnXxx" (#1311) (d20938c), closes #878 awslabs/jsii#283 awslabs/jsii#270
• update CloudFormation resources v2.18.0 (#1407) (0f80b56), closes #1409
• aws-codebuild: allow setting Webhook for GitHub Sources. (#1387) (d5cae61)
• aws-ec2: can now use PrefixList in ingress rules (#1360) (c3cfcd5)
• aws-iam: configure ExternalId for Role (#1359) (3d200c9), closes #235
• aws-lambda: Add python 3.7 runtime (#1379) (8c733ef)
• cdk: add the CodeDeployLambdaAlias Update Policy. (#1346) (d648b58), closes #1177
• core: convert "/" in construct id to "--" and disallow tokens (#1375) (011aac0), closes #1351 #1374
• iam: CompositePrincipal and allow multiple principal types (#1377) (b942ae5), closes #1201

BREAKING CHANGES TO EXPERIMENTAL FEATURES

• aws-cloudformation: this changes the type of the role property in CFN CodePipeline Actions from Role to IRole. This is needed to use imported Roles when creating Actions.
• aws-codebuild: this changes the API of CodeBuild's GitHub and BitBucket Sources to take an owner/repo pair instead of an entire cloneUrl, to make it consistent with the GitHubSourceAction in the CodePipeline package. Also adds handling the reportBuildStatus and insecureSsl Source properties.
• codebuild: the includeBuildID property of S3BucketBuildArtifacts was renamed to includeBuildId (note the lower-case trailing d).