README.md

aws-lambda-codedeploy-trigger

Trigger AWS CodeDeploy from terraform apply — synchronously.

---

Why this exists

Terraform can create CodeDeploy applications and deployment groups, but it cannot start a deployment. With ECS Blue/Green that means changing your task definition in Terraform leaves the live service untouched until somebody manually clicks Deploy. There is no aws_codedeploy_deployment resource and aws_ecs_service with the CODE_DEPLOY controller will not roll out new task revisions on its own.

This Lambda closes the loop:

1. Terraform builds the new task definition / AppSpec.
2. aws_lambda_invocation calls this Lambda with the AppSpec.
3. The Lambda creates a CodeDeploy deployment and waits until it Succeeds or Fails.
4. terraform apply blocks until the deployment finishes — success or non-zero exit.

flowchart LR
    TF["terraform apply"] -- "aws_lambda_invocation" --> L["Lambda: codedeploy-trigger"]
    L -- "CreateDeployment" --> CD["AWS CodeDeploy"]
    CD -- "Blue/Green shift" --> ECS["ECS service"]
    L -- "GetDeployment (poll)" --> CD
    L -- "JSON result" --> TF

Loading

Features

• Synchronous: blocks terraform apply until the deployment reaches a terminal state.
• Returns structured JSON (deploymentId, status, timestamps) — readable from aws_lambda_invocation.<name>.result.
• Optional fire-and-forget mode (wait: false).
• Configurable poll interval (POLL_INTERVAL_SECONDS).
• Forwards every CodeDeploy CreateDeployment knob you commonly need: description, auto-rollback, ignore application stop failures.
• Single static binary, provided.al2023 runtime, ~5 MB zipped, supports arm64 and x86_64.

Quick start (Terraform + ECS Blue/Green)

The exact pattern this project is designed for:

locals {
  appspec = {
    version = "0.0"
    Resources = [{
      TargetService = {
        Type = "AWS::ECS::Service"
        Properties = {
          TaskDefinition = module.ecs_service.task_definition_arn
          LoadBalancerInfo = {
            ContainerName = local.container_name
            ContainerPort = local.container_port
          }
          PlatformVersion = "LATEST"
        }
      }
    }]
  }
}

resource "aws_lambda_invocation" "deploy" {
  function_name = var.codedeploy_lambda_function_name

  input = jsonencode({
    applicationName     = module.code_deploy.name
    deploymentGroupName = module.code_deploy.name
    revision = {
      revisionType = "AppSpecContent"
      appSpecContent = {
        content = jsonencode(local.appspec)
        sha256  = sha256(jsonencode(local.appspec))
      }
    }
  })

  triggers = {
    task_definition_arn = module.ecs_service.task_definition_arn
  }

  depends_on = [
    module.code_deploy,
    module.ecs_service,
    module.alb_ingress,
  ]
}

output "deployment_id" {
  value = jsondecode(aws_lambda_invocation.deploy.result).deploymentId
}

End-to-end runnable examples:

• examples/terraform/ — provision the Lambda function from a release artifact.
• examples/terraform-ecs-blue-green/ — full ECS Blue/Green flow.

Event schema

The handler accepts a JSON object whose keys match the AWS CodeDeploy CreateDeployment API in lower-camel-case.

Field	Type	Required	Description
applicationName	string	yes	CodeDeploy application name.
deploymentGroupName	string	yes	CodeDeploy deployment group name.
revision	object	yes	A standard CodeDeploy RevisionLocation. For ECS Blue/Green use revisionType: "AppSpecContent".
description	string	no	Description attached to the deployment.
ignoreApplicationStopFailures	bool	no	Forwarded to CreateDeployment.
autoRollbackConfiguration	object	no	CodeDeploy AutoRollbackConfiguration.
wait	bool	no	Default true. Set to false to return immediately after CreateDeployment without polling.

Result schema

{
  "deploymentId": "d-XXXXXXXXX",
  "status": "Succeeded",
  "createdAt": "2026-05-09T10:00:00Z",
  "completedAt": "2026-05-09T10:05:30Z"
}

A failed deployment returns the same shape plus a non-empty errorMessage field on the Lambda invocation, which causes aws_lambda_invocation to fail the Terraform run.

Configuration

Env var	Default	Description
POLL_INTERVAL_SECONDS	15	Interval between GetDeployment polls. Lower it for faster feedback on small deployments.

The AWS region is taken from the standard Lambda environment — no extra variables required.

IAM policy for the Lambda role

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "codedeploy:CreateDeployment",
        "codedeploy:GetDeployment",
        "codedeploy:GetDeploymentConfig",
        "codedeploy:RegisterApplicationRevision"
      ],
      "Resource": "*"
    },
    {
      "Effect": "Allow",
      "Action": "iam:PassRole",
      "Resource": "arn:aws:iam::*:role/<codedeploy-service-role>"
    }
  ]
}

Plus the standard AWSLambdaBasicExecutionRole for CloudWatch Logs.

Known constraints

• AWS Lambda hard limit of 15 minutes. If your deployment can take longer (large fleets, slow Blue/Green traffic shifts), either tune CodeDeploy wait_time_in_minutes and the deployment configuration to fit, or invoke the Lambda with wait: false and poll deployment status from elsewhere.
• aws_lambda_invocation re-runs on every change to its triggers map. Keep triggers precise (e.g. task_definition_arn) to avoid spurious deployments.

Releases

Each tagged GitHub Release ships two ready-to-use Lambda zip artifacts:

• lambda-codedeploy-trigger_<version>_linux_amd64.zip
• lambda-codedeploy-trigger_<version>_linux_arm64.zip

Pin a version in your Terraform config and download via archive_file, null_resource + curl, or by uploading to S3.

Building from source

git clone https://github.com/dmitryint/aws-lambda-codedeploy-trigger.git
cd aws-lambda-codedeploy-trigger
make package          # builds amd64 + arm64 zips into ./package
make test             # runs unit tests with -race

Contributing

Issues and pull requests are welcome. Please run make test and go vet ./... before opening a PR.

License

MIT © 2026 Dmitry K.