Terraform AWS module for Step Function setup

Generic repository for a terraform module for AWS Step Function

Table of content

• Introduction
• Usage
• Release log
• Module versioning & git
• Local terraform setup
• Authors/Contributors

Intro

Module to create a AWS step function/state-machine with the following details:

• AWS IAM role to be used by state machine
• AWS Cloudwatch trigger to invoke the step function
• AWS Step function/state-machine

Optionally:

• Accepts additional IAM policy defined outside to enhance state machine permissions

Usage

Example usage:

// Example policy to allow Step Function to invoke a Lambda function
data "aws_iam_policy_document" "state_machine_policy" {
  statement {
    effect = "Allow"

    actions = [
      "lambda:InvokeFunction",
    ]

    resources = [
      // substitute here your lambda ARN
      "aws_lambda_function_arn",
    ]
  }

  statement {
    effect = "Allow"

    actions = [
      "cloudwatch:DescribeAlarms",
      "cloudwatch:PutMetricAlarm",
      "cloudwatch:PutMetricData",
    ]

    resources = ["*"]
  }
}

data "template_file" "state_machine_definition" {
  // optionally substitute your lambda function ARN, to be injected on your step function template file
  vars {
    aws_lambda_function_arn          = "aws_lambda_function_arn"
  }
  // adjust here your template JSON definition
  template = "${file("${path.module}/templates/basic-lambda-state-machine.tpl")}"
}

module "state_machine" {
  source                            = "github.com/diogoaurelio/terraform-module-aws-compute-step-function"
    version                         = "v0.0.1"
  aws_region                        = "eu-west-1"
  aws_account_id                    = "${data.aws_caller_identity.current.account_id}"
  environment                       = "dev"
  project                           = "analytics"
  aws_sfn_state_machine_definition  = "${data.template_file.state_machine_definition.rendered}"
  state_machine_execution_data      = "some-parameter-that-will-be-injected-into-first-state-machine"
  state_machine_name                = "my-state-machine"
  state_machine_schedule_expression = "rate(1 day)"
  additional_policy                 = "${data.aws_iam_policy_document.state_machine_policy.json}"
  attach_additional_policy          = true
}

Release log

Whenever you bump this module's version, please add a summary description of the changes performed, so that collaboration across developers becomes easier.

• version v0.0.1 - first module release

Module versioning & git

To update this module please follow the following proceedure:

1. make your changes following the normal git workflow
2. after merging the your changes to master, comes the most important part, namely versioning using tags:

git tag v0.0.2

3. push the tag to the remote git repository:

git push origin master tag v0.0.2

Local terraform setup

• Install Terraform

brew install terraform

• In order to automatic format terraform code (and have it cleaner), we use pre-commit hook. To install pre-commit.
• Run pre-commit install to setup locally hook for terraform code cleanup.

pre-commit install

Authors/Contributors

See the list of contributors who participated in this project.