CloudFormation Linter

Python code to create a binary that can be used to lint check CloudFormation templates.

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

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

Parameters

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

• -h, --help - Show this help message and exit
• --template TEMPLATE - CloudFormation Template
• --format {quiet,parseable,json} - Output Format
• --list-rules - List all the rules
• --regions [REGIONS [REGIONS ...]] - List the regions to validate against.
• --ignore-bad-template - Ignore failures with Bad template
• --append-rules [RULESDIR [RULESDIR ...]] - Specify one or more rules directories using one or more --append-rules arguments.
• --ignore-checks [IGNORE_CHECKS [IGNORE_CHECKS ...]] - Only check rules whose id do not match these values
• --log-level {info,debug} - Log Level
• --version - Version of cfn-lint

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