yamllint

yamllint documentation

Version in MegaLinter: 1.33.0
Visit Official Web Site
See How to configure yamllint rules
- If custom .yamllint.yml config file isn't found, .yamllint.yml will be used
See Index of problems detected by yamllint

Configuration in MegaLinter

Enable yamllint by adding YAML_YAMLLINT in ENABLE_LINTERS variable
Disable yamllint by adding YAML_YAMLLINT in DISABLE_LINTERS variable

Variable	Description	Default value
YAML_YAMLLINT_ARGUMENTS	User custom arguments to add in linter CLI call Ex: `-s --foo "bar"`
YAML_YAMLLINT_COMMAND_REMOVE_ARGUMENTS	User custom arguments to remove from command line before calling the linter Ex: `-s --foo "bar"`
YAML_YAMLLINT_FILTER_REGEX_INCLUDE	Custom regex including filter Ex: `(src\\|lib)`	Include every file
YAML_YAMLLINT_FILTER_REGEX_EXCLUDE	Custom regex excluding filter Ex: `(test\\|examples)`	Exclude no file
YAML_YAMLLINT_CLI_LINT_MODE	Override default CLI lint mode - `file`: Calls the linter for each file - `list_of_files`: Call the linter with the list of files as argument - `project`: Call the linter from the root of the project	`list_of_files`
YAML_YAMLLINT_FILE_EXTENSIONS	Allowed file extensions. `"*"` matches any extension, `""` matches empty extension. Empty list excludes all files Ex: `[".py", ""]`	`[".yml", ".yaml"]`
YAML_YAMLLINT_FILE_NAMES_REGEX	File name regex filters. Regular expression list for filtering files by their base names using regex full match. Empty list includes all files Ex: `["Dockerfile(-.+)?", "Jenkinsfile"]`	Include every file
YAML_YAMLLINT_PRE_COMMANDS	List of bash commands to run before the linter	None
YAML_YAMLLINT_POST_COMMANDS	List of bash commands to run after the linter	None
YAML_YAMLLINT_UNSECURED_ENV_VARIABLES	List of env variables explicitly not filtered before calling YAML_YAMLLINT and its pre/post commands	None
YAML_YAMLLINT_CONFIG_FILE	yamllint configuration file nameUse `LINTER_DEFAULT` to let the linter find it	`.yamllint.yml`
YAML_YAMLLINT_RULES_PATH	Path where to find linter configuration file	Workspace folder, then MegaLinter default rules
YAML_YAMLLINT_DISABLE_ERRORS	Run linter but consider errors as warnings	`false`
YAML_YAMLLINT_DISABLE_ERRORS_IF_LESS_THAN	Maximum number of errors allowed	`0`
YAML_YAMLLINT_CLI_EXECUTABLE	Override CLI executable	`['yamllint']`

IDE Integration

Use yamllint in your favorite IDE to catch errors before MegaLinter !

	IDE	Extension Name	Install
	Emacs	flycheck	Visit Web Site
	vim	ale	Visit Web Site

MegaLinter Flavours

This linter is available in the following flavours

Flavor	Description	Embedded linters
all	Default MegaLinter Flavor	121
c_cpp	Optimized for pure C/C++ projects	55
ci_light	Optimized for CI items (Dockerfile, Jenkinsfile, JSON/YAML schemas,XML	22
cupcake	MegaLinter for the most commonly used languages	85
documentation	MegaLinter for documentation projects	51
dotnet	Optimized for C, C++, C# or VB based projects	64
dotnetweb	Optimized for C, C++, C# or VB based projects with JS/TS	73
go	Optimized for GO based projects	53
java	Optimized for JAVA based projects	55
javascript	Optimized for JAVASCRIPT or TYPESCRIPT based projects	60
php	Optimized for PHP based projects	54
python	Optimized for PYTHON based projects	62
ruby	Optimized for RUBY based projects	51
rust	Optimized for RUST based projects	51
salesforce	Optimized for Salesforce based projects	55
swift	Optimized for SWIFT based projects	51
terraform	Optimized for TERRAFORM based projects	55

Behind the scenes

How are identified applicable files

File extensions: .yml, .yaml

How the linting is performed

yamllint is called once with the list of files as arguments (list_of_files CLI lint mode)

Example calls

yamllint myfile.yaml

yamllint -c .yamllint.yml myfile.yaml

Help content

usage: yamllint [-h] [-] [-c CONFIG_FILE | -d CONFIG_DATA] [--list-files]
                [-f {parsable,standard,colored,github,auto}] [-s]
                [--no-warnings] [-v]
                [FILE_OR_DIR ...]

A linter for YAML files. yamllint does not only check for syntax validity, but
for weirdnesses like key repetition and cosmetic problems such as lines
length, trailing spaces, indentation, etc.

positional arguments:
  FILE_OR_DIR           files to check

options:
  -h, --help            show this help message and exit
  -                     read from standard input
  -c CONFIG_FILE, --config-file CONFIG_FILE
                        path to a custom configuration
  -d CONFIG_DATA, --config-data CONFIG_DATA
                        custom configuration (as YAML source)
  --list-files          list files to lint and exit
  -f {parsable,standard,colored,github,auto}, --format {parsable,standard,colored,github,auto}
                        format for parsing output
  -s, --strict          return non-zero exit code on warnings as well as
                        errors
  --no-warnings         output only error level problems
  -v, --version         show program's version number and exit

Installation on mega-linter Docker image

PIP packages (Python):
- yamllint