Manage cloudformation stacks

cf.sh

#!/bin/bash

# Set default region (you can modify this)
AWS_REGION="us-east-1"

# Error handling function
error_exit() {
  echo "Error: $1" >&2
  exit 1
}

# Usage function
usage() {
  echo "Usage: $0 <action> <stack_name> <template_file> [-r region]"
  echo "Actions:"
  echo "  create      Create a new CloudFormation stack."
  echo "  update      Update an existing CloudFormation stack."
  echo "  delete      Delete a CloudFormation stack."
  exit 1
}

# Check for required arguments
if [ $# -lt 3 ]; then
  usage
fi

action="$1"
stack_name="$2"
template_file="$3"

shift 3

# Optional region argument
if [ "$1" == "-r" ]; then
  AWS_REGION="$2"
  shift 2
fi

# Validate action
case "$action" in
  create|update|delete)
    ;;
  *)
    error_exit "Invalid action. Choose from create, update, or delete."
    ;;
esac

# Validate stack name
if [[ ! "$stack_name" =~ ^[a-zA-Z0-9-]+$ ]]; then
  error_exit "Invalid stack name. Allowed characters: alphanumeric and hyphens."
fi

# Validate template file existence
if [ ! -f "$template_file" ]; then
  error_exit "Template file '$template_file' not found."
fi

# AWS CLI command based on action
aws_command=""
case "$action" in
  create)
    aws_command="aws cloudformation create-stack"
    ;;
  update)
    aws_command="aws cloudformation update-stack"
    ;;
  delete)
    aws_command="aws cloudformation delete-stack"
    ;;
esac

# Set common parameters
aws_command="$aws_command --stack-name $stack_name --template-body file://$template_file --region $AWS_REGION"

# Action-specific parameters
case "$action" in
  create)
    # Allow empty string for capabilities
    aws_command="$aws_command --capabilities CAPABILITY_NAMED_IAM"
    ;;
  update)
    # Add rollback and change-set-name for updates
    aws_command="$aws_command --capabilities CAPABILITY_NAMED_IAM --rollback-triggers Replace --change-set-name ${stack_name}-update"
    ;;
  delete)
    # No additional parameters needed
    ;;
esac

# Execute the AWS CLI command
echo "Executing command: $aws_command"
eval "$aws_command" || error_exit "AWS CLI command failed."

echo "Stack '$stack_name' $actioned successfully."