lambda.tf

# zip python code files
data "archive_file" "lambda_stop_package" {
  type        = "zip"
  source_file = "stop_code.py"
  output_path = "stop_code.zip"
}

data "archive_file" "lambda_start_package" {
  type        = "zip"
  source_file = "start_code.py"
  output_path = "start_code.zip"
}

# Create lambda function's role
resource "aws_iam_role" "lambda_start_stop_EC2_role" {
  name = "lambda_start_stop_EC2_role"

  assume_role_policy = jsonencode({
    Version = "2012-10-17",
    Statement = [
      {
        Action = "sts:AssumeRole",
        Effect = "Allow",
        Principal = {
          Service = "lambda.amazonaws.com"
        }
      }
    ]
  })
}

# Create policy to give lambda function permissive access to EC2
resource "aws_iam_policy" "lambda_start_stop_EC2" {
  name        = "lambda_start_stop_EC2"
  description = "allows lambda to stop & start instances"

  policy = jsonencode({
    Version : "2012-10-17",
    Statement : [
      {
        Effect : "Allow",
        Action : [
          "logs:CreateLogGroup",
          "logs:CreateLogStream",
          "logs:PutLogEvents"
        ],
        Resource : "arn:aws:logs:*:*:*"
      },
      {
        Effect : "Allow",
        Action : [
          "ec2:Start*",
          "ec2:Stop*"
        ],
        Resource : "*"
      },
    ]
  })
}

# Attach policy to lambda's role
resource "aws_iam_role_policy_attachment" "lambda_policy_attachment" {
  policy_arn = aws_iam_policy.lambda_start_stop_EC2.arn
  role       = aws_iam_role.lambda_start_stop_EC2_role.name
}


# Create stop lambda function
resource "aws_lambda_function" "stop_EC2" {
  function_name    = "stop_EC2"
  filename         = "stop_code.zip"
  role             = aws_iam_role.lambda_start_stop_EC2_role.arn
  handler          = "stop_code.lambda_handler"
  source_code_hash = data.archive_file.lambda_stop_package.output_base64sha256
  runtime          = "python3.9"
  timeout          = 10
}

# Create start lambda function
resource "aws_lambda_function" "start_EC2" {
  function_name    = "start_EC2"
  filename         = "start_code.zip"
  role             = aws_iam_role.lambda_start_stop_EC2_role.arn
  handler          = "start_code.lambda_handler"
  source_code_hash = data.archive_file.lambda_start_package.output_base64sha256
  runtime          = "python3.9"
  timeout          = 10
}