Shape
Shape

This page documents the CLI commands and options available with Terragrunt:

CLI commands

Terragrunt supports the following CLI commands:

All OpenTofu/Terraform built-in commands

Terragrunt is an orchestration tool for OpenTofu/Terraform, so except for a few of the special commands defined in these docs, Terragrunt forwards all other commands to OpenTofu/Terraform. For example, when you run terragrunt apply, Terragrunt executes tofu apply/terraform apply.

Examples:

terragrunt plan
terragrunt apply
terragrunt output
terragrunt destroy
# etc

Run terraform --help to get the full list.

run-all

Runs the provided OpenTofu/Terraform command against a stack. The command will recursively find terragrunt units in the current directory tree and run the OpenTofu/Terraform command in dependency order (unless the command is destroy, in which case the command is run in reverse dependency order).

Make sure to read Execute OpenTofu/Terraform commands on multiple modules at once for context.

Example:

terragrunt run-all apply

This will recursively search the current working directory for any folders that contain Terragrunt units and run apply in each one, concurrently, while respecting ordering defined via dependency and dependencies blocks.

[WARNING] Use run-all with care if you have unapplied dependencies.

If you have a stack of Terragrunt units with dependencies between them—either via dependency blocks or terraform_remote_state data sources—and you’ve never deployed them, then commands like run-all plan will fail, as it will not be possible to resolve the dependency blocks or terraform_remote_state data sources!

The solution for this is to take advantage of mock outputs in dependency blocks.

[WARNING] Do not set TF_PLUGIN_CACHE_DIR when using run-all

Instead take advantage of the built-in Provider Cache Server that mitigates some of the limitations of using the OpenTofu/Terraform Provider Plugin Cache directly.

Note that we are working with the OpenTofu team to improve this behavior so that you don’t have to worry about this.

[NOTE] Using run-all with apply or destroy silently adds the -auto-approve flag to the command line arguments passed to OpenTofu/Terraform due to issues with shared stdin making individual approvals impossible.

[NOTE] Using the OpenTofu/Terraform -detailed-exitcode flag with the run-all command results in an aggregate exit code being returned, rather than the exit code of any particular unit.

The algorithm for determining the aggregate exit code is as follows:

  • If any unit throws a 1, Terragrunt will throw a 1.
  • If any unit throws a 2, but nothing throws a 1, Terragrunt will throw a 2.
  • If nothing throws a non-zero, Terragrunt will throw a 0.

plan-all (DEPRECATED: use run-all)

DEPRECATED: Use run-all plan instead.

Display the plans of a stack by running terragrunt plan in each subfolder. Make sure to read Execute OpenTofu/Terraform commands on multiple modules at once for context.

Example:

terragrunt run-all plan

This will recursively search the current working directory for any folders that contain Terragrunt modules and run plan in each one, concurrently, while respecting ordering defined via dependency and dependencies blocks.

[WARNING] run-all plan is currently broken for certain use cases. If you have a stack of Terragrunt modules with dependencies between them—either via dependency blocks or terraform_remote_state data sources—and you’ve never deployed them, then run-all plan will fail as it will not be possible to resolve the dependency blocks or terraform_remote_state data sources! Please see here for more information.

apply-all (DEPRECATED: use run-all)

DEPRECATED: Use run-all apply instead.

Apply a stack by running terragrunt apply in each subfolder. Make sure to read Execute OpenTofu/Terraform commands on multiple modules at once for context.

Example:

terragrunt apply-all

This will recursively search the current working directory for any folders that contain Terragrunt modules and run apply in each one, concurrently, while respecting ordering defined via dependency and dependencies blocks.

[NOTE] Using apply-all silently adds the -auto-approve flag to the command line arguments passed to OpenTofu/Terraform due to issues with shared stdin making individual approvals impossible. Please see here for more information

output-all (DEPRECATED: use run-all)

DEPRECATED: Use run-all output instead.

Display the outputs of a stack by running terragrunt output in each subfolder. Make sure to read Execute OpenTofu/Terraform commands on multiple modules at once for context.

Example:

terragrunt output-all

This will recursively search the current working directory for any folders that contain Terragrunt modules and run output in each one, concurrently, while respecting ordering defined via dependency and dependencies blocks.

[WARNING] output-all is currently broken for certain use cases. If you have a stack of Terragrunt modules with dependencies between them—either via dependency blocks or terraform_remote_state data sources—and you’ve never deployed them, then output-all will fail as it will not be possible to resolve the dependency blocks or terraform_remote_state data sources! Please see here for more information.

destroy-all (DEPRECATED: use run-all)

DEPRECATED: Use run-all destroy instead.

Destroy a stack by running terragrunt destroy in each subfolder. Make sure to read Execute OpenTofu/Terraform commands on multiple modules at once for context.

Example:

terragrunt destroy-all

This will recursively search the current working directory for any folders that contain Terragrunt modules and run destroy in each one, concurrently, while respecting ordering defined via dependency and dependencies blocks.

[NOTE] Using destroy-all silently adds the -auto-approve flag to the command line arguments passed to OpenTofu/Terraform due to issues with shared stdin making individual approvals impossible. Please see here for more information

validate-all (DEPRECATED: use run-all)

DEPRECATED: Use run-all validate instead.

Validate stack by running terragrunt validate in each subfolder. Make sure to read Execute OpenTofu/Terraform commands on multiple modules at once for context.

Example:

terragrunt validate-all

This will recursively search the current working directory for any folders that contain Terragrunt modules and run validate in each one, concurrently, while respecting ordering defined via dependency and dependencies blocks.

terragrunt-info

Emits limited terragrunt state on stdout in a JSON format and exits.

Example:

terragrunt terragrunt-info

Might produce output such as:

{
  "ConfigPath": "/example/path/terragrunt.hcl",
  "DownloadDir": "/example/path/.terragrunt-cache",
  "IamRole": "",
  "TerraformBinary": "terraform",
  "TerraformCommand": "terragrunt-info",
  "WorkingDir": "/example/path"
}

validate-inputs

Emits information about the input variables that are configured with the given terragrunt configuration. Specifically, this command will print out unused inputs (inputs that are not defined as an OpenTofu/Terraform variable in the corresponding module) and undefined required inputs (required OpenTofu/Terraform variables that are not currently being passed in).

Example:

> terragrunt validate-inputs
The following inputs passed in by terragrunt are unused:

    - foo
    - bar


The following required inputs are missing:

    - baz

Note that this only checks for variables passed in in the following ways:

  • Configured inputs attribute.

  • var files defined on terraform.extra_arguments blocks using required_var_files and optional_var_files.

  • -var-file and -var CLI arguments defined on terraform.extra_arguments using arguments.

  • -var-file and -var CLI arguments passed to terragrunt.

  • Automatically loaded var files (terraform.tfvars, terraform.tfvars.json, *.auto.tfvars, *.auto.tfvars.json)

  • TF_VAR environment variables defined on terraform.extra_arguments blocks.

  • TF_VAR environment variables defined in the environment.

Be aware that other ways to pass variables to tofu/terraform are not checked by this command.

Additionally, there are two modes in which the validate-inputs command can be run: relaxed (default) and strict.

If you run the validate-inputs command without flags, relaxed mode will be enabled by default. In relaxed mode, any unused variables that are passed, but not used by the underlying OpenTofu/Terraform configuration, will generate a warning, but not an error. Missing required variables will always return an error, whether validate-inputs is running in relaxed or strict mode.

To enable strict mode, you can pass the --terragrunt-strict-validate flag like so:

> terragrunt validate-inputs --terragrunt-strict-validate

When running in strict mode, validate-inputs will return an error if there are unused inputs.

This command will exit with an error if terragrunt detects any unused inputs or undefined required inputs.

graph-dependencies

Prints the terragrunt dependency graph, in DOT format, to stdout. You can generate charts from DOT format using tools such as GraphViz.

Example:

terragrunt graph-dependencies

This will recursively search the current working directory for any folders that contain Terragrunt modules and build the dependency graph based on dependency and dependencies blocks. This may produce output such as:

digraph {
  "mgmt/bastion-host" ;
  "mgmt/bastion-host" -> "mgmt/vpc";
  "mgmt/bastion-host" -> "mgmt/kms-master-key";
  "mgmt/kms-master-key" ;
  "mgmt/vpc" ;
  "stage/backend-app" ;
  "stage/backend-app" -> "stage/vpc";
  "stage/backend-app" -> "mgmt/bastion-host";
  "stage/backend-app" -> "stage/mysql";
  "stage/backend-app" -> "stage/search-app";
  "stage/frontend-app" ;
  "stage/frontend-app" -> "stage/vpc";
  "stage/frontend-app" -> "mgmt/bastion-host";
  "stage/frontend-app" -> "stage/backend-app";
  "stage/mysql" ;
  "stage/mysql" -> "stage/vpc";
  "stage/redis" ;
  "stage/redis" -> "stage/vpc";
  "stage/search-app" ;
  "stage/search-app" -> "stage/vpc";
  "stage/search-app" -> "stage/redis";
  "stage/vpc" ;
  "stage/vpc" -> "mgmt/vpc";
}

hclfmt

Recursively find hcl files and rewrite them into a canonical format.

Example:

terragrunt hclfmt

This will recursively search the current working directory for any folders that contain Terragrunt configuration files and run the equivalent of tofu fmt/terraform fmt on them.

hclvalidate

Find all hcl files from the configuration stack and validate them.

Example:

terragrunt hclvalidate

This will search all hcl files from the configuration stack in the current working directory and run the equivalent of tofu validate/terraform validate on them.

For convenience in programmatically parsing these findings, you can also pass the --terragrunt-hclvalidate-json flag to output the results in JSON format.

Example:

terragrunt hclvalidate --terragrunt-hclvalidate-json

In addition, you can pass the --terragrunt-hclvalidate-show-config-path flag to only output paths of the invalid config files, delimited by newlines. This can be especially useful when combined with the terragrunt-excludes-file flag.

Example:

terragrunt hclvalidate --terragrunt-hclvalidate-show-config-path

aws-provider-patch

Overwrite settings on nested AWS providers to work around several OpenTofu/Terraform bugs. Due to issue #13018 and issue #26211, the import command may fail if your OpenTofu/Terraform code uses a module that has a provider block nested within it that sets any of its attributes to computed values. This command is a hacky attempt at working around this problem by allowing you to temporarily hard-code those attributes so import can work.

You specify which attributes to hard-code using the --terragrunt-override-attr option, passing it ATTR=VALUE, where ATTR is the attribute name and VALUE is the new value. VALUE is assumed to be a json encoded string, which means that you must have quotes (e.g., --terragrunt-override-attr 'region="eu-west-1"'). Additionally, note that ATTR can specify attributes within a nested block by specifying <BLOCK>.<ATTR>, where <BLOCK> is the block name.

For example, let’s say you had a provider block in a module that looked like this:

provider "aws" {
  region              = var.aws_region
  allowed_account_ids = var.allowed_account_ids
  assume_role {
    role_arn = var.role_arn
  }
}

Both the region and role_arn parameters are set to dynamic values, which will trigger those OpenTofu/Terraform bugs. To work around it, run the following command:

# NOTE: The single quotes around the args is to allow you to pass through the " character in the args via bash quoting
# rules.
terragrunt aws-provider-patch \
  --terragrunt-override-attr 'region="eu-west-1"' \
  --terragrunt-override-attr 'assume_role.role_arn=""' \
  --terragrunt-override-attr 'allowed_account_ids=["00000000"]'

When you run the command above, Terragrunt will:

  1. Run tofu init/terraform init to download the code for all your modules into .terraform/modules.
  2. Scan all the OpenTofu/Terraform code in .terraform/modules, find AWS provider blocks, and for each one, hard-code:
    1. The region param to "eu-west-1".
    2. The role_arn within the assume_role block to "".
    3. The allowed_account_ids param to ["0000000"].

The result will look like this:

provider "aws" {
  region              = "eu-west-1"
  allowed_account_ids = ["0000000"]
  assume_role {
    role_arn = ""
  }
}

This should allow you to run import on the module and work around those OpenTofu/Terraform bugs. When you’re done running import, remember to delete your overridden code! E.g., Delete the .terraform or .terragrunt-cache folders.

render-json

Render out the final interpreted terragrunt.hcl file (that is, with all the includes merged, dependencies resolved/interpolated, function calls executed, etc) as json.

Example:

The following terragrunt.hcl:

locals {
  aws_region = "us-east-1"
}

inputs = {
  aws_region = local.aws_region
}

Renders to the following terragrunt_rendered.json:

{
  "locals": { "aws_region": "us-east-1" },
  "inputs": { "aws_region": "us-east-1" }
  // NOTE: other attributes are omitted for brevity
}

You can use the CLI option --terragrunt-json-out to configure where terragrunt renders out the json representation.

To generate json with metadata can be specified argument --with-metadata which will add metadata to the json output.

Example:

{
  "inputs": {
    "aws_region": {
      "metadata": {
        "found_in_file": "/example/terragrunt.hcl"
      },
      "value": "us-east-1"
    }
  },
  "locals": {
    "aws_region": {
      "metadata": {
        "found_in_file": "/example/terragrunt.hcl"
      },
      "value": "us-east-1"
    }
  }
  // NOTE: other attributes are omitted for brevity
}

output-module-groups

Output groups of modules ordered for apply (or destroy) as a list of list in JSON.

Example:

terragrunt output-module-groups <sub-command>

Optional sub-commands:

  • apply (default)
  • destroy

This will recursively search the current working directory for any folders that contain Terragrunt modules and build the dependency graph based on dependency and dependencies blocks and output the graph as a JSON list of list (unless the sub-command is destroy, in which case the command will output the reverse dependency order).

This can be be useful in several scenarios, such as in CICD, when determining apply order or searching for all files to apply with CLI options such as --terragrunt-modules-that-include

This may produce output such as:

{
  "Group 1": ["stage/frontend-app"],
  "Group 2": ["stage/backend-app"],
  "Group 3": ["mgmt/bastion-host", "stage/search-app"],
  "Group 4": ["mgmt/kms-master-key", "stage/mysql", "stage/redis"],
  "Group 5": ["stage/vpc"],
  "Group 6": ["mgmt/vpc"]
}

scaffold

Generate Terragrunt files from existing OpenTofu/Terraform modules.

More details in scaffold section.

catalog

Launch the user interface for searching and managing your module catalog.

More details in catalog section.

graph

Run the provided OpenTofu/Terraform command against the graph of dependencies for the module in the current working directory. The graph consists of all modules that depend on the module in the current working directory via a depends_on or dependencies block, plus all the modules that depend on those modules, and all the modules that depend on those modules, and so on, recursively up the tree, up to the Git repository root, or the path specified via the optional --terragrunt-graph-root argument.

The Command will be executed following the order of dependencies: so it’ll run on the module in the current working directory first, then on modules that depend on it directly, then on the modules that depend on those modules, and so on. Note that if the command is destroy, it will execute in the opposite order of the dependencies.

Example: Having below dependencies: dependency-graph

Running terragrunt graph apply in eks module will lead to the following execution order:

Group 1
- Module project/eks

Group 2
- Module project/services/eks-service-1
- Module project/services/eks-service-2

Group 3
- Module project/services/eks-service-2-v2
- Module project/services/eks-service-3
- Module project/services/eks-service-5

Group 4
- Module project/services/eks-service-3-v2
- Module project/services/eks-service-4

Group 5
- Module project/services/eks-service-3-v3

Notes:

  • lambda modules aren’t included in the graph, because they are not dependent on eks module.
  • execution is from bottom up based on dependencies

Running terragrunt graph destroy in eks module will lead to the following execution order:

Group 1
- Module project/services/eks-service-2-v2
- Module project/services/eks-service-3-v3
- Module project/services/eks-service-4
- Module project/services/eks-service-5

Group 2
- Module project/services/eks-service-3-v2

Group 3
- Module project/services/eks-service-3

Group 4
- Module project/services/eks-service-1
- Module project/services/eks-service-2

Group 5
- Module project/eks

Notes:

  • execution is in reverse order, first are destroyed “top” modules and in the end eks
  • lambda modules aren’t affected at all

Running terragrunt graph apply in services/eks-service-3:

Group 1
- Module project/services/eks-service-3

Group 2
- Module project/services/eks-service-3-v2
- Module project/services/eks-service-4

Group 3
- Module project/services/eks-service-3-v3

Notes:

  • in execution are included only services dependent from eks-service-3

Running terragrunt graph destroy in services/eks-service-3:

Group 1
- Module project/services/eks-service-3-v3
- Module project/services/eks-service-4

Group 2
- Module project/services/eks-service-3-v2

Group 3
- Module project/services/eks-service-3

Notes:

  • destroy will be executed only on subset of services dependent from eks-service-3

CLI options

Terragrunt forwards all options to OpenTofu/Terraform. The only exceptions are --version and arguments that start with the prefix --terragrunt- (e.g., --terragrunt-config). The currently available options are:

terragrunt-config

CLI Arg: --terragrunt-config
Environment Variable: TERRAGRUNT_CONFIG
Requires an argument: --terragrunt-config /path/to/terragrunt.hcl

A custom path to the terragrunt.hcl or terragrunt.hcl.json file. The default path is terragrunt.hcl (preferred) or terragrunt.hcl.json in the current directory (see Configuration for a slightly more nuanced explanation). This argument is not used with the run-all commands.

terragrunt-tfpath

CLI Arg: --terragrunt-tfpath
Environment Variable: TERRAGRUNT_TFPATH
Requires an argument: --terragrunt-tfpath /path/to/terraform-binary

A custom path to the OpenTofu/Terraform binary. The default is tofu in a directory on your PATH.

NOTE: This will override the terraform binary that is used by terragrunt in all instances, including dependency lookups. This setting will also override any terraform_binary configuration values specified in the terragrunt.hcl config for both the top level, and dependency lookups.

terragrunt-no-auto-init

CLI Arg: --terragrunt-no-auto-init
Environment Variable: TERRAGRUNT_NO_AUTO_INIT (set to true)
(Prior to Terragrunt v0.48.6, this environment variable was called TERRAGRUNT_AUTO_INIT (set to false), and is still available for backwards compatibility)

When passed in, don’t automatically run terraform init when other commands are run (e.g. terragrunt apply). Useful if you want to pass custom arguments to terraform init that are specific to a user or execution environment, and therefore cannot be specified as extra_arguments. For example, -plugin-dir. You must run terragrunt init yourself in this case if needed. terragrunt will fail if it detects that init is needed, but auto init is disabled. See Auto-Init

terragrunt-no-auto-approve

CLI Arg: --terragrunt-no-auto-approve
Environment Variable: TERRAGRUNT_NO_AUTO_APPROVE (set to true)
(Prior to Terragrunt v0.48.6, this environment variable was called TERRAGRUNT_AUTO_APPROVE (set to false), and is still available for backwards compatibility) Commands:

When passed in, Terragrunt will no longer automatically append -auto-approve to the underlying OpenTofu/Terraform commands run with run-all. Note that due to the interactive prompts, this flag will also automatically assume --terragrunt-parallelism 1.

terragrunt-no-auto-retry

CLI Arg: --terragrunt-no-auto-retry
Environment Variable: TERRAGRUNT_NO_AUTO_RETRY (set to true)
(Prior to Terragrunt v0.48.6, this environment variable was called TERRAGRUNT_AUTO_RETRY (set to false), and is still available for backwards compatibility)

When passed in, don’t automatically retry commands which fail with transient errors. See Auto-Retry

terragrunt-non-interactive

CLI Arg: --terragrunt-non-interactive
Environment Variable: TERRAGRUNT_NON_INTERACTIVE (set to true)
(Prior to Terragrunt v0.48.6, this environment variable was called TF_INPUT (set to false), and is still available for backwards compatibility. NOTE: TF_INPUT is native to OpenTofu/Terraform!)

When passed in, don’t show interactive user prompts. This will default the answer for all Terragrunt (not OpenTofu/Terraform) prompts to yes except for the listed cases below. This is useful if you need to run Terragrunt in an automated setting (e.g. from a script). May also be specified with the TF_INPUT environment variable.

This setting will default to no for the following cases:

Note that this does not impact the behavior of OpenTofu/Terraform commands invoked by Terragrunt.

e.g.

terragrunt --terragrunt-non-interactive apply -auto-approve

Is how you would make Terragrunt apply without any user prompts from Terragrunt or OpenTofu/Terraform.

terragrunt-working-dir

CLI Arg: --terragrunt-working-dir
Environment Variable: TERRAGRUNT_WORKING_DIR
Requires an argument: --terragrunt-working-dir /path/to/working-directory

Set the directory where Terragrunt should execute the terraform command. Default is the current working directory. Note that for the run-all commands, this parameter has a different meaning: Terragrunt will apply or destroy all the OpenTofu/Terraform modules in the subfolders of the terragrunt-working-dir, running terraform in the root of each module it finds.

terragrunt-download-dir

CLI Arg: --terragrunt-download-dir
Environment Variable: TERRAGRUNT_DOWNLOAD
Requires an argument: --terragrunt-download-dir /path/to/dir-to-download-terraform-code

The path where to download OpenTofu/Terraform code when using remote OpenTofu/Terraform configurations. Default is .terragrunt-cache in the working directory. We recommend adding this folder to your .gitignore.

terragrunt-source

CLI Arg: --terragrunt-source
Environment Variable: TERRAGRUNT_SOURCE
Requires an argument: --terragrunt-source /path/to/local-terraform-code

Download OpenTofu/Terraform configurations from the specified source into a temporary folder, and run OpenTofu/Terraform in that temporary folder. The source should use the same syntax as the OpenTofu/Terraform module source parameter. If you specify this argument for the run-all commands, Terragrunt will assume this is the local file path for all of your OpenTofu/Terraform modules, and for each module processed by the run-all command, Terragrunt will automatically append the path of source parameter in each module to the --terragrunt-source parameter you passed in.

terragrunt-source-map

CLI Arg: --terragrunt-source-map
Environment Variable: TERRAGRUNT_SOURCE_MAP (encoded as comma separated value, e.g., source1=dest1,source2=dest2)
Requires an argument: --terragrunt-source-map git::ssh://github.com=/path/to/local-terraform-code

Can be supplied multiple times: --terragrunt-source-map source1=dest1 --terragrunt-source-map source2=dest2

The --terragrunt-source-map source=dest param replaces any source URL (including the source URL of a config pulled in with dependency blocks) that has root source with dest.

For example:

terragrunt apply --terragrunt-source-map github.com/org/modules.git=/local/path/to/modules

The above would replace terraform { source = "github.com/org/modules.git//xxx" } with terraform { source = /local/path/to/modules//xxx } regardless of whether you were running apply, or run-all, or using a dependency.

NOTE: This setting is ignored if you pass in --terragrunt-source.

Note that this only performs literal matches on the URL portion. For example, a map key of ssh://[email protected]/gruntwork-io/terragrunt.git will only match terragrunt configurations with source source = "ssh://[email protected]/gruntwork-io/terragrunt.git//xxx" and not sources of the form source = "git::ssh://[email protected]/gruntwork-io/terragrunt.git//xxx". The latter requires a map key of git::ssh://[email protected]/gruntwork-io/terragrunt.git.

terragrunt-source-update

CLI Arg: --terragrunt-source-update
Environment Variable: TERRAGRUNT_SOURCE_UPDATE (set to true)

When passed in, delete the contents of the temporary folder before downloading OpenTofu/Terraform source code into it.

terragrunt-ignore-dependency-errors

CLI Arg: --terragrunt-ignore-dependency-errors
Environment Variable: TERRAGRUNT_IGNORE_DEPENDENCY_ERRORS

When passed in, the *-all commands continue processing components even if a dependency fails

terragrunt-iam-role

CLI Arg: --terragrunt-iam-role
Environment Variable: TERRAGRUNT_IAM_ROLE
Requires an argument: --terragrunt-iam-role "arn:aws:iam::ACCOUNT_ID:role/ROLE_NAME"

Assume the specified IAM role ARN before running OpenTofu/Terraform or AWS commands. This is a convenient way to use Terragrunt and OpenTofu/Terraform with multiple AWS accounts.

terragrunt-iam-assume-role-duration

CLI Arg: --terragrunt-iam-assume-role-duration
Environment Variable: TERRAGRUNT_IAM_ASSUME_ROLE_DURATION
Requires an argument: --terragrunt-iam-assume-role-duration 3600

Uses the specified duration as the session duration (in seconds) for the STS session which assumes the role defined in --terragrunt-iam-role.

terragrunt-iam-assume-role-session-name

CLI Arg: --terragrunt-iam-assume-role-session-name
Environment Variable: TERRAGRUNT_IAM_ASSUME_ROLE_SESSION_NAME
Requires an argument: --terragrunt-iam-assume-role-session-name "terragrunt-iam-role-session-name"

Used as the session name for the STS session which assumes the role defined in --terragrunt-iam-role.

terragrunt-iam-web-identity-token

CLI Arg: --terragrunt-iam-web-identity-token
Environment Variable: TERRAGRUNT_IAM_ASSUME_ROLE_WEB_IDENTITY_TOKEN
Requires an argument: --terragrunt-iam-web-identity-token [/path/to/web-identity-token | web-identity-token-value]

Used as the web identity token for assuming a role temporarily using the AWS Security Token Service (STS) with the AssumeRoleWithWebIdentity API.

terragrunt-excludes-file

CLI Arg: --terragrunt-excludes-file
Environment Variable: TERRAGRUNT_EXCLUDES_FILE
Requires an argument: --terragrunt-excludes-file /path/to/file

Path to a file with a list of directories that need to be excluded when running *-all commands, by default .terragrunt-excludes. Modules under these directories will be excluded during execution of the commands. If a relative path is specified, it should be relative from –terragrunt-working-dir. This will only exclude the module, not its dependencies.

This flag has been designed to integrate nicely with the hclvalidate command, which can return a list of invalid files delimited by newlines when passed the --terragrunt-hclvalidate-show-config-path flag. To integrate the two, you can run something like the following using bash process substitution:

terragrunt run-all plan --terragrunt-excludes-file <(terragrunt hclvalidate --terragrunt-hclvalidate-show-config-path)

terragrunt-exclude-dir

CLI Arg: --terragrunt-exclude-dir
Environment Variable: TERRAGRUNT_EXCLUDE_DIR
Requires an argument: --terragrunt-exclude-dir /path/to/dirs/to/exclude*

Can be supplied multiple times: --terragrunt-exclude-dir /path/to/dirs/to/exclude --terragrunt-exclude-dir /another/path/to/dirs/to/exclude

Unix-style glob of directories to exclude when running *-all commands. Modules under these directories will be excluded during execution of the commands. If a relative path is specified, it should be relative from –terragrunt-working-dir. Flag can be specified multiple times. This will only exclude the module, not its dependencies.

Please note that the glob curly braces expansion is not taken in account using environment variable unlike of its equivalent as a parameter on the command line. You should consider using TERRAGRUNT_EXCLUDE_DIR="foo/module,bar/module" instead of TERRAGRUNT_EXCLUDE_DIR="{foo,bar}/module".

terragrunt-include-dir

CLI Arg: --terragrunt-include-dir
Environment Variable: TERRAGRUNT_INCLUDE_DIR
Requires an argument: --terragrunt-include-dir /path/to/dirs/to/include*

Can be supplied multiple times: --terragrunt-include-dir /path/to/dirs/to/include --terragrunt-include-dir /another/path/to/dirs/to/include

Unix-style glob of directories to include when running *-all commands. Only modules under these directories (and all dependent modules) will be included during execution of the commands. If a relative path is specified, it should be relative from --terragrunt-working-dir. Flag can be specified multiple times.

Please note that the glob curly braces expansion is not taken in account using environment variable unlike of its equivalent as a parameter on the command line. You should consider using TERRAGRUNT_INCLUDE_DIR="foo/module,bar/module" instead of TERRAGRUNT_INCLUDE_DIR="{foo,bar}/module".

terragrunt-strict-include

CLI Arg: --terragrunt-strict-include
Environment Variable: TERRAGRUNT_STRICT_INCLUDE

When passed in, only modules under the directories passed in with –terragrunt-include-dir will be included. All dependencies of the included directories will be excluded if they are not in the included directories. If no –terragrunt-include-dir flags are included, terragrunt will not include any modules during the execution of the commands.

terragrunt-strict-validate

CLI Arg: --terragrunt-strict-validate

When passed in, and running terragrunt validate-inputs, enables strict mode for the validate-inputs command. When strict mode is enabled, an error will be returned if any variables required by the underlying OpenTofu/Terraform configuration are not passed in, OR if any unused variables are passed in. By default, terragrunt validate-inputs runs in relaxed mode. In relaxed mode, an error is only returned when a variable required by the underlying OpenTofu/Terraform configuration is not passed in.

terragrunt-ignore-dependency-order

CLI Arg: --terragrunt-ignore-dependency-order
Environment Variable: TERRAGRUNT_IGNORE_DEPENDENCY_ORDER

When passed in, ignore the dependencies between modules when running *-all commands.

terragrunt-ignore-external-dependencies

CLI Arg: --terragrunt-ignore-external-dependencies
Environment Variable: TERRAGRUNT_IGNORE_EXTERNAL_DEPENDENCIES

When passed in, don’t attempt to include any external dependencies when running *-all commands. Note that an external dependency is a dependency that is outside the current terragrunt working directory, and is not respective to the included directories with terragrunt-include-dir.

terragrunt-include-external-dependencies

CLI Arg: --terragrunt-include-external-dependencies
Environment Variable: TERRAGRUNT_INCLUDE_EXTERNAL_DEPENDENCIES

When passed in, include any external dependencies when running *-all without asking. Note that an external dependency is a dependency that is outside the current terragrunt working directory, and is not respective to the included directories with terragrunt-include-dir.

terragrunt-parallelism

CLI Arg: --terragrunt-parallelism
Environment Variable: TERRAGRUNT_PARALLELISM

When passed in, limit the number of modules that are run concurrently to this number during *-all commands. The exception is the terraform init command, which is always executed sequentially if the terraform plugin cache is used. This is because the terraform plugin cache is not guaranteed to be concurrency safe.

terragrunt-debug

CLI Arg: --terragrunt-debug
Environment Variable: TERRAGRUNT_DEBUG

When passed in, Terragrunt will create a tfvars file that can be used to invoke the terraform module in the same way that Terragrunt invokes the module, so that you can debug issues with the terragrunt config. See Debugging for some additional details.

terragrunt-log-level

CLI Arg: --terragrunt-log-level
Environment Variable: TERRAGRUNT_LOG_LEVEL
Requires an argument: --terragrunt-log-level <LOG_LEVEL>

When passed it, sets logging level for terragrunt. All supported levels are:

  • stderr
  • stdout
  • error
  • warn
  • info (this is the default)
  • debug
  • trace

Where the first two control the logging of Terraform/OpenTofu output.

terragrunt-log-format

CLI Arg: --terragrunt-log-format
Environment Variable: TERRAGRUNT_LOG_FORMAT
Requires an argument: --terragrunt-log-format <LOG_FORMAT>

There are four log format presets:

  • pretty (this is the default)
  • bare (old Terragrunt logging, pre-v0.67.0)
  • json
  • key-value

terragrunt-log-custom-format

CLI Arg: --terragrunt-log-custom-format
Environment Variable: TERRAGRUNT_LOG_CUSTOM_FORMAT
Requires an argument: --terragrunt-log-custom-format <LOG_CUSTOM_FORMAT>

This allows you to customize logging however you like.

Make sure to read Custom Log Format for syntax details.

terragrunt-log-disable

CLI Arg: --terragrunt-log-disable
Environment Variable: TERRAGRUNT_LOG_DISABLE

Disable logging. This flag also enables terragrunt-forward-tf-stdout.

terragrunt-log-show-abs-paths

CLI Arg: --terragrunt-log-show-abs-paths
Environment Variable: TERRAGRUNT_LOG_SHOW_ABS_PATHS

If specified, Terragrunt paths in logs will be absolute. By default, the paths are relative to the working directory.

terragrunt-no-color

CLI Arg: --terragrunt-no-color
Environment Variable: TERRAGRUNT_NO_COLOR

If specified, Terragrunt output won’t contain any color.

NOTE: This option does not disable OpenTofu/Terraform output colors. Use the OpenTofu/Terraform -no-color argument.

terragrunt-check

CLI Arg: --terragrunt-check
Environment Variable: TERRAGRUNT_CHECK (set to true)
Commands:

When passed in, run hclfmt in check only mode instead of actively overwriting the files. This will cause the command to exit with exit code 1 if there are any files that are not formatted.

terragrunt-diff

CLI Arg: --terragrunt-diff
Environment Variable: TERRAGRUNT_DIFF (set to true)
Commands:

When passed in, running hclfmt will print diff between original and modified file versions.

terragrunt-hclfmt-file

CLI Arg: --terragrunt-hclfmt-file
Requires an argument: --terragrunt-hclfmt-file /path/to/terragrunt.hcl
Commands:

When passed in, run hclfmt only on the specified file.

terragrunt-hclfmt-exclude-dir

CLI Arg: --terragrunt-hclfmt-exclude-dir .dir-name
Environment Variable: TERRAGRUNT_HCLFMT_EXCLUDE_DIR
Commands:

Can be supplied multiple times: --terragrunt-hclfmt-exclude-dir .back --terragrunt-hclfmt-exclude-dir .archive
When passed in, hclfmt will ignore files in the specified directories.

terragrunt-hclfmt-stdin

CLI Arg: --terragrunt-hclfmt-stdin
Environment Variable: TERRAGRUNT_HCLFMT_STDIN (set to true)
Commands:

When passed in, run hclfmt only on hcl passed to stdin, result is printed to stdout.

terragrunt-hclvalidate-json

CLI Arg: --terragrunt-hclvalidate-json
Environment Variable: TERRAGRUNT_HCLVALIDATE_JSON (set to true)
Commands:

When passed in, render the output in the JSON format.

terragrunt-hclvalidate-show-config-path

CLI Arg: --terragrunt-hclvalidate-show-config-path
Environment Variable: TERRAGRUNT_HCLVALIDATE_INVALID (set to true)
Commands:

When passed in, output a list of files with invalid configuration.

terragrunt-override-attr

CLI Arg: --terragrunt-override-attr
Requires an argument: --terragrunt-override-attr ATTR=VALUE

Override the attribute named ATTR with the value VALUE in a provider block as part of the aws-provider-patch command. May be specified multiple times. Also, ATTR can specify attributes within a nested block by specifying <BLOCK>.<ATTR>, where <BLOCK> is the block name: e.g., assume_role.role arn will override the role_arn attribute of the assume_role { ... } block.

terragrunt-json-out

CLI Arg: --terragrunt-json-out
Requires an argument: --terragrunt-json-out /path/to/terragrunt_rendered.json
Commands:

When passed in, render the json representation in this file.

terragrunt-json-disable-dependent-modules

CLI Arg: --terragrunt-json-disable-dependent-modules
Requires an argument: --terragrunt-json-disable-dependent-modules
Commands:

When the --terragrunt-json-disable-dependent-modules flag is included in the command, the process of identifying dependent modules will be disabled during JSON rendering. This lead to a faster rendering process, but the output will not include any dependent modules.

terragrunt-modules-that-include

CLI Arg: --terragrunt-modules-that-include
Environment Variable: TERRAGRUNT_MODULES_THAT_INCLUDE
Requires an argument: --terragrunt-modules-that-include /path/to/included-terragrunt.hcl
Commands:

When passed in, run-all will only run the command against Terragrunt modules that include the specified file.

This applies to the set of modules that are identified based on all the existing criteria for deciding which modules to include. For example, consider the following folder structure:

.
├── _envcommon
│   └── data-stores
│       └── aurora.hcl
├── dev
│   └── us-west-2
│       └── dev
│           ├── data-stores
│           │   └── aurora
│           │       └── terragrunt.hcl
│           └── networking
│               └── vpc
│                   └── terragrunt.hcl
└── stage
    └── us-west-2
        └── stage
            ├── data-stores
            │   └── aurora
            │       └── terragrunt.hcl
            └── networking
                └── vpc
                    └── terragrunt.hcl

Suppose that both dev/us-west-2/dev/data-stores/aurora/terragrunt.hcl and stage/us-west-2/stage/data-stores/aurora/terragrunt.hcl had the following contents:

include "envcommon" {
  path = "../../../../../_envcommon/data-stores/aurora.hcl"
}

If you run the command run-all init --terragrunt-modules-that-include ../_envcommon/data-stores/aurora.hcl from the dev folder, only dev/us-west-2/dev/data-stores/aurora will be run; not stage/us-west-2/stage/data-stores/aurora. This is because run-all by default restricts the modules to only those that are direct descendents of the current folder you are running from. If you also pass in --terragrunt-include-dir ../stage, then it will now include stage/us-west-2/stage/data-stores/aurora because now the stage folder is in consideration.

In other words, Terragrunt will always first find all the modules that should be included before applying this filter, and then will apply this filter on the set of modules that it found.

You can pass this argument in multiple times to provide a list of include files to consider. When multiple files are passed in, the set will be the union of modules that includes at least one of the files in the list.

NOTE: When using relative paths, the paths are relative to the working directory. This is either the current working directory, or any path passed in to terragrunt-working-dir.

TIP: This flag is functionally covered by the --terragrunt-queue-include-units-reading flag, but is more explicitly only for the include configuration block.

terragrunt-queue-include-units-reading

CLI Arg: --terragrunt-queue-include-units-reading
Environment Variable: TERRAGRUNT_QUEUE_INCLUDE_UNITS_READING
Commands:

This flag works very similarly to the --terragrunt-modules-that-include flag, but instead of looking only for included configurations, it also looks for configurations that read a given file.

When passed in, the *-all commands will include all units (modules) that read a given file into the queue. This is useful when you want to trigger an update on all units that read or include a given file using HCL functions in their configurations.

Consider the following folder structure:

.
├── reading-shared-hcl
│   └── terragrunt.hcl
├── also-reading-shared-hcl
│   └── terragrunt.hcl
├── not-reading-shared-hcl
│   └── terragrunt.hcl
└── shared.hcl

Suppose that reading-shared-hcl and also-reading-shared-hcl both read shared.hcl in their configurations, like so:

locals {
 shared = read_terragrunt_config(find_in_parent_folders("shared.hcl"))
}

If you run the command run-all init --terragrunt-queue-include-units-reading shared.hcl from the root folder, both reading-shared-hcl and also-reading-shared-hcl will be run; not not-reading-shared-hcl.

This is because the read_terragrunt_config HCL function has a special hook that allows Terragrunt to track that it has read the file shared.hcl. This hook is used by all native HCL functions that Terragrunt supports which read files.

Note, however, that there are certain scenarios where Terragrunt may not be able to track that a file has been read this way.

For example, you may be using a bash script to read a file via run_cmd, or reading the file via OpenTofu code. To support these use-cases, the mark_as_read function can be used to manually mark a file as read.

That would look something like this:

locals {
  filename = mark_as_read("file-read-by-tofu.txt")
}

inputs = {
  filename = local.filename
}

⚠️: Due to the way that Terragrunt parses configurations during a run-all, functions will only properly mark files as read if they are used in the locals block. Reading a file directly in the inputs block will not mark the file as read, as the inputs block is not evaluated until after the queue has been populated with units to run.

terragrunt-fetch-dependency-output-from-state

CLI Arg: --terragrunt-fetch-dependency-output-from-state
Environment Variable: TERRAGRUNT_FETCH_DEPENDENCY_OUTPUT_FROM_STATE (set to true)

When using many dependencies, this option can speed up the dependency processing by fetching dependency output directly from the state file instead of init dependencies and running terraform on them. NOTE: This is an experimental feature, use with caution. Currently only AWS S3 backend is supported.

terragrunt-use-partial-parse-config-cache

CLI Arg: --terragrunt-use-partial-parse-config-cache
Environment Variable: TERRAGRUNT_USE_PARTIAL_PARSE_CONFIG_CACHE (set to true)

This flag can be used to drastically decrease time required for parsing Terragrunt files. The effect will only show if a lot of similar includes are expected such as the root terragrunt.hcl include. NOTE: This is an experimental feature, use with caution.

The reason you might want to use this flag is that Terragrunt frequently only needs to perform a partial parse of Terragrunt configurations.

This is the case for scenarios like:

  • Building the Directed Acyclic Graph (DAG) during a run-all command where only the dependency blocks need to be evaluated to determine run order.
  • Parsing the terraform block to determine state configurations for fetching dependency outputs.
  • Determining whether Terragrunt execution behavior has to change like for prevent_destroy or skip flags in configuration.

These configurations are generally safe to cache, but due to the nature of HCL being a dynamic configuration language, there are some edge cases where caching these can lead to incorrect behavior.

Once this flag has been tested thoroughly, we will consider making it the default behavior.

terragrunt-include-module-prefix

DEPRECATED: Since this behavior has become by default, this flag has been removed. In order to get raw Terraform/OpenTofu output, use terragrunt-forward-tf-stdout.

CLI Arg: --terragrunt-include-module-prefix
Environment Variable: TERRAGRUNT_INCLUDE_MODULE_PREFIX (set to true)

When this flag is set output from OpenTofu/Terraform sub-commands is prefixed with module path.

terragrunt-fail-on-state-bucket-creation

CLI Arg: --terragrunt-fail-on-state-bucket-creation
Environment Variable: TERRAGRUNT_FAIL_ON_STATE_BUCKET_CREATION (set to true)

When this flag is set, Terragrunt will fail and exit if it is necessary to create the remote state bucket.

terragrunt-disable-bucket-update

CLI Arg: --terragrunt-disable-bucket-update
Environment Variable: TERRAGRUNT_DISABLE_BUCKET_UPDATE (set to true)

When this flag is set, Terragrunt does not update the remote state bucket, which is useful to set if the state bucket is managed by a third party.

terragrunt-disable-command-validation

CLI Arg: --terragrunt-disable-command-validation
Environment Variable: TERRAGRUNT_DISABLE_COMMAND_VALIDATION (set to true)

When this flag is set, Terragrunt will not validate the terraform command, which can be useful when need to use non-existent commands in hooks.

terragrunt-json-log

DEPRECATED: Use terragrunt-log-format.

CLI Arg: --terragrunt-json-log
Environment Variable: TERRAGRUNT_JSON_LOG (set to true)

When this flag is set, Terragrunt will output its logs in JSON format.

terragrunt-tf-logs-to-json

DEPRECATED: Use terragrunt-log-format. OpenTofu/Terraform stdout and stderr is wrapped in JSON by default with --terragurnt-log-format json flag if --terragrunt-forward-tf-stdout flag is not specified. In other words, the previous behavior with the --terragrunt-json-log --terragrunt-tf-logs-to-json flags is now equivalent to --terragrunt-log-format json and the previous behavior with the --terragrunt-json-log is now equivalent to --terragrunt-log-format json --terragrunt-forward-tf-stdout.

CLI Arg: --terragrunt-tf-logs-to-json
Environment Variable: TERRAGRUNT_TF_JSON_LOG (set to true)

When this flag is set, Terragrunt will wrap OpenTofu/Terraform stdout and stderr in JSON log messages. Works only with --terragrunt-json-log flag.

terragrunt-provider-cache

CLI Arg: --terragrunt-provider-cache
Environment Variable: TERRAGRUNT_PROVIDER_CACHE
Commands:

Enables Terragrunt’s provider caching. This forces OpenTofu/Terraform to make provider requests through the Terragrunt Provider Cache server. Make sure to read Provider Caching for context.

terragrunt-provider-cache-dir

CLI Arg: --terragrunt-provider-cache-dir
Environment Variable: TERRAGRUNT_PROVIDER_CACHE_DIR
Commands:

The path to the Terragrunt provider cache directory. By default, terragrunt/providers folder in the user cache directory: $HOME/.cache on Unix systems, $HOME/Library/Caches on Darwin, %LocalAppData% on Windows. The file structure of the cache directory is identical to the OpenTofu/Terraform plugin_cache_dir directory. Make sure to read Provider Caching for context.

terragrunt-provider-cache-hostname

CLI Arg: --terragrunt-provider-cache-hostname
Environment Variable: TERRAGRUNT_PROVIDER_CACHE_HOSTNAME
Commands:

The hostname of the Terragrunt Provider Cache server. By default, ‘localhost’. Make sure to read Provider Caching for context.

terragrunt-provider-cache-port

CLI Arg: --terragrunt-provider-cache-port
Environment Variable: TERRAGRUNT_PROVIDER_CACHE_PORT
Commands:

The port of the Terragrunt Provider Cache server. By default, assigned automatically. Make sure to read Provider Caching for context.

terragrunt-provider-cache-token

CLI Arg: --terragrunt-provider-cache-token
Environment Variable: TERRAGRUNT_PROVIDER_CACHE_TOKEN
Commands:

The Token for authentication on the Terragrunt Provider Cache server. By default, assigned automatically. Make sure to read Provider Caching for context.

terragrunt-provider-cache-registry-names

CLI Arg: --terragrunt-provider-cache-registry-names
Environment Variable: TERRAGRUNT_PROVIDER_CACHE_REGISTRY_NAMES
Commands:

The list of remote registries to cached by Terragrunt Provider Cache server. By default, ‘registry.terraform.io’, ‘registry.opentofu.org’. Make sure to read Provider Caching for context.

terragrunt-out-dir

CLI Arg: --terragrunt-out-dir
Environment Variable: TERRAGRUNT_OUT_DIR
Commands:

Specify the plan output directory for the *-all commands. Useful to save plans between runs in a single place.

terragrunt-json-out-dir

CLI Arg: --terragrunt-json-out-dir
Environment Variable: TERRAGRUNT_JSON_OUT_DIR
Commands:

Specify the output directory for the *-all commands to store plans in JSON format. Useful to read plans programmatically.

terragrunt-auth-provider-cmd

CLI Arg: --terragrunt-auth-provider-cmd
Environment Variable: TERRAGRUNT_AUTH_PROVIDER_CMD
Requires an argument: --terragrunt-auth-provider-cmd "command [arguments]"

The command and arguments used to obtain authentication credentials dynamically. If specified, Terragrunt runs this command for every working directory before running the underlying IAC for a terragrunt.hcl file.

The output must be valid JSON of the following schema:

{
  "awsCredentials": {
    "ACCESS_KEY_ID": "",
    "SECRET_ACCESS_KEY": "",
    "SESSION_TOKEN": ""
  },
  "awsRole": {
    "roleARN": "",
    "sessionName": "",
    "duration": 0,
    "webIdentityToken": ""
  },
  "envs": {
    "ANY_KEY": ""
  }
}

This allows Terragrunt to acquire different credentials at runtime without changing any terragrunt.hcl configuration. You can use this flag to set arbitrary credentials for continuous integration, authentication with providers other than AWS and more.

As long as the standard output of the command passed to terragrunt-auth-provider-cmd results in JSON matching the schema above, corresponding environment variables will be set before Terragrunt begins IAC execution for a terragrunt.hcl file.

The simplest approach to leverage this flag is to write a script that fetches desired credentials, and emits them to STDOUT in the JSON format listed above:

#!/usr/bin/env bash

echo -n '{"envs": {"KEY": "a secret"}}'

You can use any technology you’d like, however, as long as Terragrunt can execute it. The expected pattern for using this flag is to populate the values dynamically using a secret store, etc.

Note that more specific configurations (e.g. awsCredentials) take precedence over less specific configurations (e.g. envs).

If you would like to set credentials for AWS with this method, you are encouraged to use awsCredentials instead of envs, as these keys will be validated to conform to the officially supported environment variables expected by the AWS SDK.

Similarly, if you would like Terragrunt to assume an AWS role on your behalf, you are encouraged to use the awsRole configuration instead of envs.

Other credential configurations will be supported in the future, but until then, if your provider authenticates via environment variables, you can use the envs field to fetch credentials dynamically from a secret store, etc before Terragrunt executes any IAC.

Note: The awsRole configuration is only used when the awsCredentials configuration is not present. If both are present, the awsCredentials configuration will take precedence.

terragrunt-disable-log-formatting

DEPRECATED: Use terragrunt-log-format.

CLI Arg: --terragrunt-disable-log-formatting
Environment Variable: TERRAGRUNT_DISABLE_LOG_FORMATTING

If specified, logs will be displayed in key/value format. By default, logs are formatted in a human readable format.

The example of what the log looks like without the --terragrunt-disable-log-formatting flag specified:

14:19:25.081 INFO   [app] Running command: tofu plan -input=false
14:19:25.174 STDOUT [app] tofu: OpenTofu used the selected providers to generate the following execution
14:19:25.174 STDOUT [app] tofu: plan. Resource actions are indicated with the following symbols:
14:19:25.174 STDOUT [app] tofu:   + create
14:19:25.174 STDOUT [app] tofu: OpenTofu will perform the following actions:

The example of what the log looks like with the --terragrunt-forward-tf-stdout flag specified:

time=2024-08-23T11:47:18+03:00 level=info prefix=app msg=Running command: tofu plan -input=false
time=2024-08-23T11:47:18+03:00 level=stdout prefix=app binary=tofu msg=OpenTofu used the selected providers to generate the following execution
time=2024-08-23T11:47:18+03:00 level=stdout prefix=app binary=tofu msg=plan. Resource actions are indicated with the following symbols:
time=2024-08-23T11:47:18+03:00 level=stdout prefix=app binary=tofu msg=  + create
time=2024-08-23T11:47:18+03:00 level=stdout prefix=app binary=tofu msg=OpenTofu will perform the following actions:

terragrunt-forward-tf-stdout

CLI Arg: --terragrunt-forward-tf-stdout
Environment Variable: TERRAGRUNT_FORWARD_TF_STDOUT

If specified, the output of Terraform/OpenTofu commands will be printed as is. By default, all logs, except when using the output command or -json flags, are integrated into the Terragrunt log.

The example of what the log looks like without the --terragrunt-forward-tf-stdout flag specified:

14:19:25.081 INFO   [app] Running command: tofu plan -input=false
14:19:25.174 STDOUT [app] tofu: OpenTofu used the selected providers to generate the following execution
14:19:25.174 STDOUT [app] tofu: plan. Resource actions are indicated with the following symbols:
14:19:25.174 STDOUT [app] tofu:   + create
14:19:25.174 STDOUT [app] tofu: OpenTofu will perform the following actions:

The example of what the log looks like with the --terragrunt-forward-tf-stdout flag specified:

14:19:25.081 INFO   [app] Running command: tofu plan -input=false

OpenTofu used the selected providers to generate the following execution
plan. Resource actions are indicated with the following symbols:
  + create

OpenTofu will perform the following actions:

terragrunt-no-destroy-dependencies-check

CLI Arg: --terragrunt-no-destroy-dependencies-check
Environment Variable: TERRAGRUNT_NO_DESTROY_DEPENDENCIES_CHECK

If specified, Terragrunt will not check dependent modules when running destroy command. By default, Terragrunt checks dependent modules when running destroy command.

feature

CLI Arg: --feature
Environment Variable: TERRAGRUNT_FEATURE

Feature flags in Terragrunt allow users to dynamically control configuration behavior through CLI arguments or environment variables.

These flags enable a more flexible and controlled deployment process, particularly in monorepo contexts with interdependent infrastructure units.

Example HCL flags definition:

feature "string_feature_flag" {
  default = "test"
}

feature "int_feature_flag" {
  default = 777
}

feature "bool_feature_flag" {
  default = false
}

terraform {
  before_hook "conditional_command" {
    commands = ["apply", "plan", "destroy"]
    execute  = feature.bool_feature_flag.value ? ["sh", "-c", "echo running conditional bool_feature_flag"] : [ "sh", "-c", "exit", "0" ]
  }
}

inputs = {
  string_feature_flag = feature.string_feature_flag.value
  int_feature_flag = feature.int_feature_flag.value
}

Setting a feature flag through the CLI:

terragrunt --feature int_feature_flag=123 --feature bool_feature_flag=true --feature string_feature_flag=app1 apply

Setting feature flags through environment variables:

export TERRAGRUNT_FEATURE=int_feature_flag=123,bool_feature_flag=true,string_feature_flag=app1
terragrunt apply