# Amazon Managed Streaming for Apache Kafka Construct Library --- ![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 your source code when upgrading to a newer version of this package. --- [Amazon MSK](https://aws.amazon.com/msk/) is a fully managed service that makes it easy for you to build and run applications that use Apache Kafka to process streaming data. The following example creates an MSK Cluster. ```go var vpc vpc cluster := msk.NewCluster(this, jsii.String("Cluster"), &ClusterProps{ ClusterName: jsii.String("myCluster"), KafkaVersion: msk.KafkaVersion_V2_8_1(), Vpc: Vpc, }) ``` ## Allowing Connections To control who can access the Cluster, use the `.connections` attribute. For a list of ports used by MSK, refer to the [MSK documentation](https://docs.aws.amazon.com/msk/latest/developerguide/client-access.html#port-info). ```go var vpc vpc cluster := msk.NewCluster(this, jsii.String("Cluster"), &ClusterProps{ ClusterName: jsii.String("myCluster"), KafkaVersion: msk.KafkaVersion_V2_8_1(), Vpc: Vpc, }) cluster.connections.AllowFrom(ec2.Peer_Ipv4(jsii.String("1.2.3.4/8")), ec2.Port_Tcp(jsii.Number(2181))) cluster.connections.AllowFrom(ec2.Peer_Ipv4(jsii.String("1.2.3.4/8")), ec2.Port_Tcp(jsii.Number(9094))) ``` ## Cluster Endpoints You can use the following attributes to get a list of the Kafka broker or ZooKeeper node endpoints ```go var cluster cluster awscdk.NewCfnOutput(this, jsii.String("BootstrapBrokers"), &CfnOutputProps{ Value: cluster.bootstrapBrokers, }) awscdk.NewCfnOutput(this, jsii.String("BootstrapBrokersTls"), &CfnOutputProps{ Value: cluster.bootstrapBrokersTls, }) awscdk.NewCfnOutput(this, jsii.String("BootstrapBrokersSaslScram"), &CfnOutputProps{ Value: cluster.bootstrapBrokersSaslScram, }) awscdk.NewCfnOutput(this, jsii.String("BootstrapBrokerStringSaslIam"), &CfnOutputProps{ Value: cluster.bootstrapBrokersSaslIam, }) awscdk.NewCfnOutput(this, jsii.String("ZookeeperConnection"), &CfnOutputProps{ Value: cluster.zookeeperConnectionString, }) awscdk.NewCfnOutput(this, jsii.String("ZookeeperConnectionTls"), &CfnOutputProps{ Value: cluster.zookeeperConnectionStringTls, }) ``` ## Importing an existing Cluster To import an existing MSK cluster into your CDK app use the `.fromClusterArn()` method. ```go cluster := msk.Cluster_FromClusterArn(this, jsii.String("Cluster"), jsii.String("arn:aws:kafka:us-west-2:1234567890:cluster/a-cluster/11111111-1111-1111-1111-111111111111-1")) ``` ## Client Authentication [MSK supports](https://docs.aws.amazon.com/msk/latest/developerguide/kafka_apis_iam.html) the following authentication mechanisms. ### TLS To enable client authentication with TLS set the `certificateAuthorityArns` property to reference your ACM Private CA. [More info on Private CAs.](https://docs.aws.amazon.com/msk/latest/developerguide/msk-authentication.html) ```go import acmpca "github.com/aws/aws-cdk-go/awscdk" var vpc vpc cluster := msk.NewCluster(this, jsii.String("Cluster"), &ClusterProps{ ClusterName: jsii.String("myCluster"), KafkaVersion: msk.KafkaVersion_V2_8_1(), Vpc: Vpc, EncryptionInTransit: &EncryptionInTransitConfig{ ClientBroker: msk.ClientBrokerEncryption_TLS, }, ClientAuthentication: msk.ClientAuthentication_Tls(&TlsAuthProps{ CertificateAuthorities: []iCertificateAuthority{ acmpca.CertificateAuthority_FromCertificateAuthorityArn(this, jsii.String("CertificateAuthority"), jsii.String("arn:aws:acm-pca:us-west-2:1234567890:certificate-authority/11111111-1111-1111-1111-111111111111")), }, }), }) ``` ### SASL/SCRAM Enable client authentication with [SASL/SCRAM](https://docs.aws.amazon.com/msk/latest/developerguide/msk-password.html): ```go var vpc vpc cluster := msk.NewCluster(this, jsii.String("cluster"), &ClusterProps{ ClusterName: jsii.String("myCluster"), KafkaVersion: msk.KafkaVersion_V2_8_1(), Vpc: Vpc, EncryptionInTransit: &EncryptionInTransitConfig{ ClientBroker: msk.ClientBrokerEncryption_TLS, }, ClientAuthentication: msk.ClientAuthentication_Sasl(&SaslAuthProps{ Scram: jsii.Boolean(true), }), }) ``` ### SASL/IAM Enable client authentication with [IAM](https://docs.aws.amazon.com/msk/latest/developerguide/iam-access-control.html): ```go var vpc vpc cluster := msk.NewCluster(this, jsii.String("cluster"), &ClusterProps{ ClusterName: jsii.String("myCluster"), KafkaVersion: msk.KafkaVersion_V2_8_1(), Vpc: Vpc, EncryptionInTransit: &EncryptionInTransitConfig{ ClientBroker: msk.ClientBrokerEncryption_TLS, }, ClientAuthentication: msk.ClientAuthentication_Sasl(&SaslAuthProps{ Iam: jsii.Boolean(true), }), }) ``` ### SASL/IAM + TLS Enable client authentication with [IAM](https://docs.aws.amazon.com/msk/latest/developerguide/iam-access-control.html) as well as enable client authentication with TLS by setting the `certificateAuthorityArns` property to reference your ACM Private CA. [More info on Private CAs.](https://docs.aws.amazon.com/msk/latest/developerguide/msk-authentication.html) ```go import acmpca "github.com/aws/aws-cdk-go/awscdk" var vpc vpc cluster := msk.NewCluster(this, jsii.String("Cluster"), &ClusterProps{ ClusterName: jsii.String("myCluster"), KafkaVersion: msk.KafkaVersion_V2_8_1(), Vpc: Vpc, EncryptionInTransit: &EncryptionInTransitConfig{ ClientBroker: msk.ClientBrokerEncryption_TLS, }, ClientAuthentication: msk.ClientAuthentication_SaslTls(&SaslTlsAuthProps{ Iam: jsii.Boolean(true), CertificateAuthorities: []iCertificateAuthority{ acmpca.CertificateAuthority_FromCertificateAuthorityArn(this, jsii.String("CertificateAuthority"), jsii.String("arn:aws:acm-pca:us-west-2:1234567890:certificate-authority/11111111-1111-1111-1111-111111111111")), }, }), }) ``` ## Logging You can deliver Apache Kafka broker logs to one or more of the following destination types: Amazon CloudWatch Logs, Amazon S3, Amazon Kinesis Data Firehose. To configure logs to be sent to an S3 bucket, provide a bucket in the `logging` config. ```go var vpc vpc var bucket iBucket cluster := msk.NewCluster(this, jsii.String("cluster"), &ClusterProps{ ClusterName: jsii.String("myCluster"), KafkaVersion: msk.KafkaVersion_V2_8_1(), Vpc: Vpc, Logging: &BrokerLogging{ S3: &S3LoggingConfiguration{ Bucket: *Bucket, }, }, }) ``` When the S3 destination is configured, AWS will automatically create an S3 bucket policy that allows the service to write logs to the bucket. This makes it impossible to later update that bucket policy. To have CDK create the bucket policy so that future updates can be made, the `@aws-cdk/aws-s3:createDefaultLoggingPolicy` [feature flag](https://docs.aws.amazon.com/cdk/v2/guide/featureflags.html) can be used. This can be set in the `cdk.json` file. ```json { "context": { "@aws-cdk/aws-s3:createDefaultLoggingPolicy": true } } ```