cfn-lint 0.0.8

checks cloudformation for practices and behaviour that could potentially be improved

Validate CloudFormation yaml/json templates against the CloudFormation spec and additional checks. Includes checking valid values for resource properties and best practices.

Warning

This is an attempt to provide validation for CloudFormation templates properties and their values. For values things can get pretty complicated (mappings, joins, splits, conditions, and nesting those functions inside each other) so its a best effort to validate those values but the promise is to not fail if we can’t understand or translate all the things that could be going on.

Install

Command line

From a command prompt run python setup.py clean --all then python setup.py install

Pip Install

pip install cfn-lint. You may need to use sudo.

Uninstall

If you have pip installed you can uninstall using pip uninstall cfn-lint. You may need to manually remove the cfn-lint binary.

Configuration

Parameters

Command Line	Metadata	Options	Description
-h, –help			Get description of cfn-lint
–template		filename	Template file path to the file that needs to be tested by cfn-lint
–format	format	quiet, parseable, json	Output format
–list-rules			List all the rules
–regions	regions	[REGIONS [REGIONS …]]	Test the template against many regions. Supported regions <https: //docs.aws.amaz on.com/AWSCloud Formation/lates t/UserGuide/cfn -resource-speci fication.html> __
–ignore-bad-tem plate	ignore_bad_temp late		Ignores bad template errors
–append-rules	append_rules	[RULESDIR [RULESDIR …]]	Specify one or more rules directories using one or more –append-rules arguments.
–ignore-checks	ignore_checks	[IGNORE_CHECKS [IGNORE_CHECKS …]]	Only check rules whose id do not match these values
–log-level	log_level	{info, debug}	Log Level
–update-specs			Update the CloudFormation Specs. You may need sudo to run this. You will need internet access when running this command
–version			Version of cfn-lint

Command Line

From a command prompt run cfn-lint --template <path to yaml template>

Metadata

Inside the root level Metadata key you can configure cfn-lint using the supported parameters.

Metadata:
  cfn-lint:
    config:
      regions:
      - us-east-1
      - us-east-2
      ignore_checks:
      - E2530

Precedence

cfn-lint applies the configuration from the CloudFormation Metadata first and then overrides those values with anything specified in the CLI.

Examples

Basic usage

cfn-lint --template template.yaml

Test a template based on multiple regions

cfn-lint --regions us-east-1 ap-south-1 --template template.yaml

E3001 Invalid Type AWS::Batch::ComputeEnvironment for resource testBatch in ap-south-1

Credit

Will Thames and ansible-lint at https://github.com/willthames/ansible-lint