Cfn-lint

https://github.com/aws-cloudformation/cfn-lint

• Installation: pip install cfn-lint

• cfn-lint
• cfn-lint -t
• cfn-lint --version

cfn-lint your_stack.yml
E0000 mapping values are not allowed in this context
your_stack.yml:5:23

Configuration files:

• .cfnlintrc

Help

cfn-lint
usage:
Basic: cfn-lint test.yaml
Ignore a rule: cfn-lint -i E3012 -- test.yaml
Configure a rule: cfn-lint -x E3012:strict=false -t test.yaml
Lint all yaml files in a folder: cfn-lint dir/**/*.yaml

CloudFormation Linter

optional arguments:
  -h, --help            show this help message and exit

Standard:
  TEMPLATE              The CloudFormation template to be linted
  -t TEMPLATE [TEMPLATE ...], --template TEMPLATE [TEMPLATE ...]
                        The CloudFormation template to be linted
  -b, --ignore-bad-template
                        Ignore failures with Bad template
  --ignore-templates IGNORE_TEMPLATES [IGNORE_TEMPLATES ...]
                        Ignore templates
  -f {quiet,parseable,json,junit,pretty}, --format {quiet,parseable,json,junit,pretty}
                        Output Format
  -l, --list-rules      list all the rules
  -r REGIONS [REGIONS ...], --regions REGIONS [REGIONS ...]
                        list the regions to validate against.
  -i IGNORE_CHECKS [IGNORE_CHECKS ...], --ignore-checks IGNORE_CHECKS [IGNORE_CHECKS ...]
                        only check rules whose id do not match these values
  -c INCLUDE_CHECKS [INCLUDE_CHECKS ...], --include-checks INCLUDE_CHECKS [INCLUDE_CHECKS ...]
                        include rules whose id match these values
  -m MANDATORY_CHECKS [MANDATORY_CHECKS ...], --mandatory-checks MANDATORY_CHECKS [MANDATORY_CHECKS ...]
                        always check rules whose id match these values, regardless of template exclusions
  -e, --include-experimental
                        Include experimental rules
  -x CONFIGURE_RULES [CONFIGURE_RULES ...], --configure-rule CONFIGURE_RULES [CONFIGURE_RULES ...]
                        Provide configuration for a rule. Format RuleId:key=value. Example: E3012:strict=false
  --config-file CONFIG_FILE
                        Specify the cfnlintrc file to use
  -z CUSTOM_RULES, --custom-rules CUSTOM_RULES
                        Allows specification of a custom rule file.
  -v, --version         Version of cfn-lint
  --output-file OUTPUT_FILE
                        Writes the output to the specified file, ideal for producing reports
  --merge-configs       Merges lists between configuration layers

Advanced / Debugging:
  -D, --debug           Enable debug logging
  -I, --info            Enable information logging
  -a APPEND_RULES [APPEND_RULES ...], --append-rules APPEND_RULES [APPEND_RULES ...]
                        specify one or more rules directories using one or more --append-rules arguments.
  -o OVERRIDE_SPEC, --override-spec OVERRIDE_SPEC
                        A CloudFormation Spec override file that allows customization
  -g, --build-graph     Creates a file in the same directory as the template that models the template's resources in DOT format
  -s REGISTRY_SCHEMAS [REGISTRY_SCHEMAS ...], --registry-schemas REGISTRY_SCHEMAS [REGISTRY_SCHEMAS ...]
                        one or more directories of CloudFormation Registry Schemas
  -u, --update-specs    Update the CloudFormation Specs

See also

• AWS CloudFormation: [aws cloudformation | create-stack | list-stacks | delete-stack | update-stack | list-types | estimate-template-cost | validate-template | describe-stacks | deploy | drift detection], aws cloudformation get-template-summary, aws cloudformation describe-stack-events
• AWS CloudFormation, AWS::CloudFormation AWS CloudFormation Designer, Drift detection, AWS Cloud Development Kit (CDK), aws cloudformation, ServicesStack:, AWS CloudFormation Linter (cfn-lint), Former2, CloudCraft, Change sets, AWS CloudFormation Public Registry, CloudFormation snippets, CloudFormation templates, StackSets, Outputs:, Type:, Fn::Sub, !Ref, CloudFormation Parameters, AWS CloudFormation Templates, CloudFormation functions