# LocalStack
## Setup
Sign up for localstack and obtain the auth token. Then fire up a container:

```bash
docker run -e LOCALSTACK_AUTH_TOKEN=ls-xxx-yyy-zzz-aaa-bbb -it \
--name localstack --network macvlan localstack/localstack-pro localstack 
```

In terraform, configure aws endpoints to go to localstack and add localstack required configurations:
```hcl
provider "aws" {
  region = var.aws-region

  # localstack config
  access_key                  = "test"
  secret_key                  = "test"
  skip_credentials_validation = true
  skip_metadata_api_check     = true
  skip_requesting_account_id  = true

  # localstack endpoints https://docs.localstack.cloud/aws/integrations/infrastructure-as-code/terraform/#:~:text=tflocal%20is%20a%20small%20wrapper,unmodified%20Terraform%20scripts%20against%20LocalStack.
  endpoints {
    apigateway     = "http://192.168.86.96:4566"
    apigatewayv2   = "http://192.168.86.96:4566"
    cloudformation = "http://192.168.86.96:4566"
    cloudwatch     = "http://192.168.86.96:4566"
    dynamodb       = "http://192.168.86.96:4566"
    ec2            = "http://192.168.86.96:4566"
    es             = "http://192.168.86.96:4566"
    elasticache    = "http://192.168.86.96:4566"
    firehose       = "http://192.168.86.96:4566"
    iam            = "http://192.168.86.96:4566"
    kinesis        = "http://192.168.86.96:4566"
    lambda         = "http://192.168.86.96:4566"
    rds            = "http://192.168.86.96:4566"
    redshift       = "http://192.168.86.96:4566"
    route53        = "http://192.168.86.96:4566"
    s3             = "http://192.168.86.96:4566"
    secretsmanager = "http://192.168.86.96:4566"
    ses            = "http://192.168.86.96:4566"
    sns            = "http://192.168.86.96:4566"
    sqs            = "http://192.168.86.96:4566"
    ssm            = "http://192.168.86.96:4566"
    stepfunctions  = "http://192.168.86.96:4566"
    sts            = "http://192.168.86.96:4566"
  }
}

```

## Limitations
At time of writing, localstack seems very limited. Many basic layers would not run.
For example, vpc with ipv6 could not be created. It failed with the following error

```text
│ Error: waiting for EC2 Subnet (subnet-c113e8c02abd344e0) EnableDns64 update: timeout while waiting for state to become 'true' (last state: 'false', timeout: 5m0s)
│ 
│   with module.vpc.aws_subnet.private[1],
│   on .terraform/modules/vpc/main.tf line 293, in resource "aws_subnet" "private":
│  293: resource "aws_subnet" "private" {

```

Also, ec2 instance's associate_public_ip_address attribute is always set to true, despite
it is set to false in my code. This caused the instance to be redeployed everytime terraform
apply is ran.

The free edition of LocalStack does not include rds support