README.md

This component provisions Amazon Aurora MySQL RDS clusters and seeds relevant database information (hostnames, username, password, etc.) into AWS SSM Parameter Store.

Tip

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Usage

Stack Level: Regional

Here's an example for how to use this component.

stacks/catalog/aurora-mysql/defaults.yaml file (base component for all Aurora MySQL clusters with default settings):

components:
  terraform:
    aurora-mysql/defaults:
      metadata:
        type: abstract
      vars:
        enabled: false
        name: rds
        mysql_deletion_protection: false
        mysql_storage_encrypted: true
        aurora_mysql_engine: "aurora-mysql"
        allowed_cidr_blocks:
          # all automation
          - 10.128.0.0/22
          # all corp
          - 10.128.16.0/22
        eks_component_names:
          - eks/eks
        # https://docs.aws.amazon.com/AmazonRDS/latest/AuroraMySQLReleaseNotes/AuroraMySQL.Updates.3020.html
        # aws rds describe-db-engine-versions --engine aurora-mysql --query 'DBEngineVersions[].EngineVersion'
        aurora_mysql_engine_version: "8.0.mysql_aurora.3.02.0"
        # engine and cluster family are notoriously hard to find.
        # If you know the engine version (example here is "8.0.mysql_aurora.3.02.0"), use Engine and DBParameterGroupFamily from:
        #    aws rds describe-db-engine-versions --engine aurora-mysql --query "DBEngineVersions[]" | \
        #    jq '.[] | select(.EngineVersion == "8.0.mysql_aurora.3.02.0") |
        #       { Engine: .Engine, EngineVersion: .EngineVersion, DBParameterGroupFamily: .DBParameterGroupFamily }'
        #
        #    Returns:
        #    {
        #       "Engine": "aurora-mysql",
        #       "EngineVersion": "8.0.mysql_aurora.3.02.0",
        #       "DBParameterGroupFamily": "aurora-mysql8.0"
        #     }
        aurora_mysql_cluster_family: "aurora-mysql8.0"
        mysql_name: shared
        # 1 writer, 1 reader
        mysql_cluster_size: 2
        mysql_admin_user: "" # generate random username
        mysql_admin_password: "" # generate random password
        mysql_db_name: "" # generate random db name
        # https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/Concepts.DBInstanceClass.html
        mysql_instance_type: "db.t3.medium"
        mysql_skip_final_snapshot: false

Example configuration for a dev cluster. Import this file into the primary region. stacks/catalog/aurora-mysql/dev.yaml file (override the default settings for the cluster in the dev account):

import:
  - catalog/aurora-mysql/defaults

components:
  terraform:
    aurora-mysql/dev:
      metadata:
        component: aurora-mysql
        inherits:
          - aurora-mysql/defaults
      vars:
        instance_type: db.r5.large
        mysql_cluster_size: 1
        mysql_name: main
        mysql_db_name: main

Example deployment with primary cluster deployed to us-east-1 in a platform-dev account: atmos terraform apply aurora-mysql/dev -s platform-use1-dev

Disaster Recovery with Cross-Region Replication

This component is designed to support cross-region replication with continuous replication. If enabled and deployed, a secondary cluster will be deployed in a different region than the primary cluster. This approach is highly aggressive and costly, but in a disaster scenario where the primary cluster fails, the secondary cluster can be promoted to take its place. Follow these steps to handle a Disaster Recovery.

Usage

To deploy a secondary cluster for cross-region replication, add the following catalog entries to an alternative region:

Default settings for a secondary, replica cluster. For this example, this file is saved as stacks/catalog/aurora-mysql/replica/defaults.yaml

import:
  - catalog/aurora-mysql/defaults

components:
  terraform:
    aurora-mysql/replica/defaults:
      metadata:
        component: aurora-mysql
        inherits:
          - aurora-mysql/defaults
      vars:
        eks_component_names: []
        allowed_cidr_blocks:
          # all automation in primary region (where Spacelift is deployed)
          - 10.128.0.0/22
          # all corp in the same region as this cluster
          - 10.132.16.0/22
        mysql_instance_type: "db.t3.medium"
        mysql_name: "replica"
        primary_cluster_region: use1
        is_read_replica: true
        is_promoted_read_replica: false # False by default, added for visibility

Environment specific settings for dev as an example:

import:
  - catalog/aurora-mysql/replica/defaults

components:
  terraform:
    aurora-mysql/dev:
      metadata:
        component: aurora-mysql
        inherits:
          - aurora-mysql/defaults
          - aurora-mysql/replica/defaults
      vars:
        enabled: true
        primary_cluster_component: aurora-mysql/dev

Promoting the Read Replica

Promoting an existing RDS Replicate cluster to a fully standalone cluster is not currently supported by Terraform: https://github.com/hashicorp/terraform-provider-aws/issues/6749

Instead, promote the Replicate cluster with the AWS CLI command: aws rds promote-read-replica-db-cluster --db-cluster-identifier <identifier>

After promoting the replica, update the stack configuration to prevent future Terraform runs from re-enabling replication. In this example, modify stacks/catalog/aurora-mysql/replica/defaults.yaml

is_promoted_read_replica: true

Re-deploying the component should show no changes. For example, atmos terraform apply aurora-mysql/dev -s platform-use2-dev

Requirements

Providers

Modules

Resources

Inputs

list(object({
    vpc         = optional(string, "vpc")
    environment = optional(string)
    stage       = optional(string)
    tenant      = optional(string)
  }))

list(object({
    apply_method = string
    name         = string
    value        = string
  }))

list(object({
    apply_method = string
    name         = string
    value        = string
  }))

{
  "additional_tag_map": {},
  "attributes": [],
  "delimiter": null,
  "descriptor_formats": {},
  "enabled": true,
  "environment": null,
  "id_length_limit": null,
  "label_key_case": null,
  "label_order": [],
  "label_value_case": null,
  "labels_as_tags": [
    "unset"
  ],
  "name": null,
  "namespace": null,
  "regex_replace_chars": null,
  "stage": null,
  "tags": {},
  "tenant": null
}

[
  "eks/cluster"
]

[
  "enhanced-monitoring"
]

[
  "default"
]

[
  "audit",
  "error",
  "general",
  "slowquery"
]

Outputs

Related Projects

Check out these related projects.

• Cloud Posse Terraform Modules - Our collection of reusable Terraform modules used by our reference architectures.
• Atmos - Atmos is like docker-compose but for your infrastructure

References

For additional context, refer to some of these links.

• cloudposse-terraform-components - Cloud Posse's upstream component

✨ Contributing

This project is under active development, and we encourage contributions from our community.

Many thanks to our outstanding contributors:

For 🐛 bug reports & feature requests, please use the issue tracker.

In general, PRs are welcome. We follow the typical "fork-and-pull" Git workflow.

1. Review our Code of Conduct and Contributor Guidelines.
2. Fork the repo on GitHub
3. Clone the project to your own machine
4. Commit changes to your own branch
5. Push your work back up to your fork
6. Submit a Pull Request so that we can review your changes

NOTE: Be sure to merge the latest changes from "upstream" before making a pull request!

Running Terraform Tests

We use Atmos to streamline how Terraform tests are run. It centralizes configuration and wraps common test workflows with easy-to-use commands.

All tests are located in the test/ folder.

Under the hood, tests are powered by Terratest together with our internal Test Helpers library, providing robust infrastructure validation.

Setup dependencies:

• Install Atmos (installation guide)
• Install Go 1.24+ or newer
• Install Terraform or OpenTofu

To run tests:

• Run all tests:

  atmos test run
  

• Clean up test artifacts:

  atmos test clean
  

• Explore additional test options:

  atmos test --help
  

The configuration for test commands is centrally managed. To review what's being imported, see the atmos.yaml file.

Learn more about our automated testing in our documentation or implementing custom commands with atmos.

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License

Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements.  See the NOTICE file
distributed with this work for additional information
regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at

  https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing,
software distributed under the License is distributed on an
"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License.

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