Custom Components Example

This example demonstrates how to define custom component types in Atmos using custom commands.

Overview

Custom component types allow you to extend Atmos beyond the built-in component types (Terraform, Helmfile, Packer). You can define any component type (e.g., script, ansible, manifest) and access its configuration from stack files via Go templates.

Structure

examples/custom-components/
├── atmos.yaml                           # Atmos configuration with custom command
├── components/
│   └── script/
│       └── deploy-app/
│           └── deploy.sh                # Example script (not executed)
└── stacks/
    ├── catalog/
    │   └── script/
    │       └── deploy-app.yaml          # Base component configuration
    └── deploy/
        └── dev.yaml                     # Stack with overrides

Usage

1. Build atmos (from repo root):

   make build
   

2. Run the custom command:

   cd examples/custom-components
   ../../build/atmos script deploy-app -s dev
   

3. Expected output:

   Component: deploy-app
   Stack: dev
   App: myapp
   Version: 1.0.0
   Replicas: 1
   

How It Works

1. Custom Command Definition (atmos.yaml):

   • The script command defines a custom component type
   • Arguments and flags with type: component and semantic_type: stack identify which values to use
   • The component: section specifies the component type name

2. Stack Configuration (stacks/):

   • Components are defined under components.script.<name>
   • Standard Atmos inheritance and overrides work as expected

3. Template Access:

   • Steps can access component config via {{ .Component.* }}
   • All component sections are available: vars, settings, metadata, etc.