How To Make Your AWS EKS Cluster Use Fargate Using Pulumi And Golang

Table of Contents

Infrastructure as Code with Pulumi and Go - This article is part of a series.

Part 1: How To Create a VPC In AWS Using Pulumi And Golang

Part 2: How To Add Subnets To a VPC In AWS Using Pulumi And Golang

Part 3: How To Create An AWS EKS Cluster Using Pulumi And Golang

Part 4: This Article

Part 5: How To Create a DynamoDB Table In AWS Using Pulumi And Golang

Part 6: How To Create AWS Lambda Functions Using Pulumi And Golang

Part 7: How To Build Infrastructure as Code With Pulumi And Golang - Part 2

At re:Invent, AWS introduced the ability to run EKS pods on AWS Fargate, and Fargate is cheaper than hosting Kubernetes yourself. In the last post I created an EKS cluster, so this one adds a Fargate profile to it.

The complete project is available on GitHub.

Configuration
#

The Fargate profile needs a name, a Kubernetes namespace to target, and an IAM role for pod execution. Add this to the YAML file from the previous post:

fargate:profile-name: EKSFargateProfile
fargate:namespace: example
fargate:execution-role-arn: "arn:aws:iam::ACCOUNTID:role/EKSFargatePodExecutionRole"

For details on creating the IAM role, check the AWS docs. You can use the command line (e.g., pulumi config set fargate:profile-name "EKSFargateProfile") or edit the YAML file directly. The file is named Pulumi.<name of your project>.yaml.

Adding the Fargate profile
#

This code extends the previous post. It reads the profile name and namespace from the YAML file, references the cluster and subnets from earlier posts, and calls eks.NewFargateProfile() to attach the profile to your cluster.

// Create an EKS Fargate Profile
fargateProfileName := getEnv(ctx, "fargate:profile-name", "unknown")

selectors := make([]map[string]interface{}, 1)
namespaces := make(map[string]interface{})
namespaces["namespace"] = getEnv(ctx, "fargate:namespace", "unknown")
selectors[0] = namespaces

fargateProfileArgs := &eks.FargateProfileArgs{
    ClusterName:         clusterName,
    FargateProfileName:  fargateProfileName,
    Tags:                tags,
    SubnetIds:           subnets["subnet_ids"],
    Selectors:           selectors,
    PodExecutionRoleArn: getEnv(ctx, "fargate:execution-role-arn", "unknown"),
}

fargateProfile, err := eks.NewFargateProfile(ctx, fargateProfileName, fargateProfileArgs)
if err != nil {
    fmt.Println(err.Error())
    return err
}

ctx.Export("FARGATE-PROFILE-ID", fargateProfile.ID())

Running the code
#

Run pulumi up to add the Fargate profile. If you’re using the same project and stack, Pulumi knows the cluster already exists and will only create the new profile.

$ pulumi up
Previewing update (builderstack):

     Type                       Name                  Plan
     pulumi:pulumi:Stack        builder-builderstack
 +   └─ aws:eks:FargateProfile  EKSFargateProfile     create

Outputs:
  + FARGATE-PROFILE-ID: output<string>

Resources:
    + 1 to create
    5 unchanged

Do you want to perform this update? yes
Updating (builderstack):

     Type                       Name                  Status
     pulumi:pulumi:Stack        builder-builderstack
 +   └─ aws:eks:FargateProfile  EKSFargateProfile     created

Outputs:
    CLUSTER-ID        : "myEKSCluster"
  + FARGATE-PROFILE-ID: "myEKSCluster:EKSFargateProfile"
    SUBNET-IDS        : [
        [0]: "subnet-0a1909bec2e936bd7"
        [1]: "subnet-09d229c2eb8061979"
    ]
    VPC-ID            : "vpc-0437c750acf1050c3"

Resources:
    + 1 created
    5 unchanged

Duration: 2m27s

Permalink: https://app.pulumi.com/retgits/builder/builderstack/updates/4