tflint

If you are using the GitHub action please use the TERRAFORM_TFLINT_UNSECURED_ENV_VARIABLES: GITHUB_TOKEN to prevent plugin download issues

tflint documentation

Version in MegaLinter: 0.50.1
Visit Official Web Site
See How to configure tflint rules
- If custom .tflint.hcl config file isn't found, .tflint.hcl will be used
See How to disable tflint rules in files
See Index of problems detected by tflint

Configuration in MegaLinter

Enable tflint by adding TERRAFORM_TFLINT in ENABLE_LINTERS variable
Disable tflint by adding TERRAFORM_TFLINT in DISABLE_LINTERS variable

Variable	Description	Default value
TERRAFORM_TFLINT_SECURED_ENV	Allows to send the full env to tflint --init. Initialized with default value `true`. Set to `false` to allow `tflint --init` to access your env vars.	`True`
TERRAFORM_TFLINT_ARGUMENTS	User custom arguments to add in linter CLI call Ex: `-s --foo "bar"`
TERRAFORM_TFLINT_COMMAND_REMOVE_ARGUMENTS	User custom arguments to remove from command line before calling the linter Ex: `-s --foo "bar"`
TERRAFORM_TFLINT_FILE_EXTENSIONS	Allowed file extensions. `"*"` matches any extension, `""` matches empty extension. Empty list excludes all files Ex: `[".py", ""]`	`[".tf"]`
TERRAFORM_TFLINT_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
TERRAFORM_TFLINT_PRE_COMMANDS	List of bash commands to run before the linter	None
TERRAFORM_TFLINT_POST_COMMANDS	List of bash commands to run after the linter	None
TERRAFORM_TFLINT_UNSECURED_ENV_VARIABLES	List of env variables explicitly not filtered before calling TERRAFORM_TFLINT and its pre/post commands	None
TERRAFORM_TFLINT_CONFIG_FILE	tflint configuration file nameUse `LINTER_DEFAULT` to let the linter find it	`.tflint.hcl`
TERRAFORM_TFLINT_RULES_PATH	Path where to find linter configuration file	Workspace folder, then MegaLinter default rules
TERRAFORM_TFLINT_DISABLE_ERRORS	Run linter but consider errors as warnings	`false`
TERRAFORM_TFLINT_DISABLE_ERRORS_IF_LESS_THAN	Maximum number of errors allowed	`0`
TERRAFORM_TFLINT_CLI_EXECUTABLE	Override CLI executable	`['tflint']`

MegaLinter Flavours

This linter is available in the following flavours

Flavor	Description	Embedded linters
all	Default MegaLinter Flavor	121
cupcake	MegaLinter for the most commonly used languages	83
security	Optimized for security	23
terraform	Optimized for TERRAFORM based projects	54

Behind the scenes

How are identified applicable files

File extensions: .tf

How the linting is performed

tflint is called once on the whole project directory (project CLI lint mode)

filtering can not be done using MegaLinter configuration variables,it must be done using tflint configuration or ignore file (if existing)
VALIDATE_ALL_CODEBASE: false doesn't make tflint analyze only updated files

Example calls

tflint

tflint -c .tflint.hcl

Help content

Usage:
  tflint --chdir=DIR/--recursive [OPTIONS]

Application Options:
  -v, --version                                                 Print TFLint
                                                                version
      --init                                                    Install plugins
      --langserver                                              Start language
                                                                server
  -f, --format=[default|json|checkstyle|junit|compact|sarif]    Output format
  -c, --config=FILE                                             Config file
                                                                name (default:
                                                                .tflint.hcl)
      --ignore-module=SOURCE                                    Ignore module
                                                                sources
      --enable-rule=RULE_NAME                                   Enable rules
                                                                from the
                                                                command line
      --disable-rule=RULE_NAME                                  Disable rules
                                                                from the
                                                                command line
      --only=RULE_NAME                                          Enable only
                                                                this rule,
                                                                disabling all
                                                                other defaults.
                                                                Can be
                                                                specified
                                                                multiple times
      --enable-plugin=PLUGIN_NAME                               Enable plugins
                                                                from the
                                                                command line
      --var-file=FILE                                           Terraform
                                                                variable file
                                                                name
      --var='foo=bar'                                           Set a Terraform
                                                                variable
      --call-module-type=[all|local|none]                       Types of module
                                                                to call
                                                                (default: local)
      --chdir=DIR                                               Switch to a
                                                                different
                                                                working
                                                                directory
                                                                before
                                                                executing the
                                                                command
      --recursive                                               Run command in
                                                                each directory
                                                                recursively
      --filter=FILE                                             Filter issues
                                                                by file names
                                                                or globs
      --force                                                   Return zero
                                                                exit status
                                                                even if issues
                                                                found
      --minimum-failure-severity=[error|warning|notice]         Sets minimum
                                                                severity level
                                                                for exiting
                                                                with a non-zero
                                                                error code
      --color                                                   Enable
                                                                colorized output
      --no-color                                                Disable
                                                                colorized output
      --fix                                                     Fix issues
                                                                automatically
      --no-parallel-runners                                     Disable
                                                                per-runner
                                                                parallelism

Help Options:
  -h, --help                                                    Show this help
                                                                message

Installation on mega-linter Docker image

Dockerfile commands :

FROM ghcr.io/terraform-linters/tflint:v0.50.1 as tflint
COPY --link --from=tflint /usr/local/bin/tflint /usr/bin/