aws-s3-state terraform module

Overview

The aws-s3-state terraform module has been created to easily configure Terraform Backend, i.e. to create resources for remote state store of terraform code - AWS S3 bucket for keeping state in the terraform.tfstate file and DynamoDB table for locking this state and consistency checking. Full description of the solution with explanation available here.

The remote state configuration should be done at the environment bootstrap step. It is recommended to use aws-s3-state terraform module per project environment. If several terraform stages exist in a given environment (e.g. dev) then their state should be stored within the same AWS S3 bucket (but a separate object, e.g. terraform-${STAGE}.tfstate) using a single DynamoDB table (but a separate item, e.g. cosmos-dev-state/terraform-${STAGE}.tfstate-md5). Terraform state for aws-s3-state terraform module is not kept anywhere except your local machine (chicken and egg problem).

As mentioned earlier this module is created only 2 resources:

• aws_s3_bucket.terraform,
• aws_dynamodb_table.terraoform.

In addition, 1 output has been created, which could be used for example for logging configuration (example of use in the Usage tab):

output "tfstate_s3_bucket" {
    value = aws_s3_bucket.terraform.id
}

Usage

Required vars:

• env,
• s3_bucket,
• s3_bucket_name,
• dynamodb_table.

module "tfstate" {
    source = "github.com/Airnauts/terraform-s3-state.git?ref=v0.0.1"

    env            = "cosmos-dev"
    s3_bucket      = "cosmos-dev-state"
    s3_bucket_name = "cosmos-dev Terraform State "
    dynamodb_table = "cosmos-dev-state"
}

resource "aws_s3_bucket" "log_bucket" {
    bucket = "${module.tfstate.tfstate_s3_bucket}-log-bucket"
}