AWS CloudFormation Linter (cfn-lint)

import subprocess
import os

# Create a dummy CloudFormation template file with an intentional error
template_content = """
AWSTemplateFormatVersion: '2010-09-09'
Resources:
  MyS3Bucket:
    Type: AWS::S3::Bucket
    Properties:
      BucketName: my-unique-bucket-name
      # Intentional error: 'InvalidProperty' is not a valid S3 Bucket property
      InvalidProperty: true
"""

template_file = "./my_bad_template.yaml"
with open(template_file, "w") as f:
    f.write(template_content)

print(f"Linting {template_file} with cfn-lint...")

try:
    # Run cfn-lint as a subprocess
    # --format text is default, but explicit for clarity
    # --non-zero-exit-code error ensures a non-zero exit if errors are found
    result = subprocess.run(
        ['cfn-lint', template_file, '--non-zero-exit-code', 'error'],
        capture_output=True, text=True, check=False
    )

    print("\n--- cfn-lint Output ---")
    print(result.stdout)
    if result.stderr:
        print("\n--- cfn-lint Errors ---")
        print(result.stderr)

    if result.returncode != 0:
        print(f"\ncfn-lint found issues! Exit Code: {result.returncode}")
    else:
        print("\ncfn-lint found no issues.")

except FileNotFoundError:
    print("Error: cfn-lint command not found. Please ensure it's installed and in your PATH.")
except Exception as e:
    print(f"An unexpected error occurred: {e}")
finally:
    # Clean up the dummy template file
    if os.path.exists(template_file):
        os.remove(template_file)
        print(f"\nCleaned up {template_file}")