Set of Python-based CLI tools for working with Terraform configurations in bulk
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auto.tfvars
inheritance. Terrawrap makes it easier to share variables between Terraform directories through inheritance ofauto.tfvars
files. -
Remote backend generation. Terrawrap makes it easier to work with remote state backends by generating configuration for them.
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Repository level plan/apply. Terrawrap provides commands for running plan/apply recursively on a entire repository at once.
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Repository level dependency visualization. Terrawrap provides commands for displaying the order of applies in human readable output.
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Automatically download third-party Terraform plugins
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Make Terraform DRY for large organizations. A Terraform best practices is to break up Terraform configs into many small state files. This leads to an explosion in boilerplate code when using Terraform in large organizations with 100s of state files. Terrawrap reduces some boilerplate code by providing
auto.tfvars
inheritance and generating backend configurations. -
Make Terraform code easier to manage. Terraform only runs commands on a single directory at a time. This makes working with hundreds of terraform directories/state files hard. Terrawrap provides utilities for running commands against an entire repository at once instead of one directory at a time.
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All Terraform code should be valid Terraform. Any Terraform code used with Terrawrap should be runnable with Terraform by itself without the wrapper. Terrawrap does not provide any new syntax.
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Terrawrap is not a code generator. Generated code is harder to read and understand. Code generators tend to lead to leaky abstractions that can be more trouble than they are worth. However, Terrawrap does generate remote backend configs as a workaround to Terraform's lack of support for variables in backend configs (See hashicorp/terraform#13022). We expect this to be the only instance of code generation in Terrawrap.
Terrawrap requires Python 3.7.0 or higher to run.
This package can be installed using pip
pip3 install terrawrap
You should now be able to use the tf
command.
For development, tox>=2.9.1
is recommended.
Terrawrap uses tox
. You will need to install tox with pip install tox
.
Running tox
will automatically execute the unit tests.
You can also run them individually with the -e
argument.
For example, tox -e py37-unit
will run the unit tests for python 3.7
To see all the available options, run tox -l
.
Terrawrap can be configured via a .tf_wrapper
file. The wrapper will walk the provided configuration
path and look for .tf_wrapper
files. The files are merged in the order that they are discovered. Consider
the below example:
foo
├── bar
│ └── .tf_wrapper
└── .tf_wrapper
If there are conflicting configurations between those two .tf_wrapper
files, the .tf_wrapper
file in
foo/bar
will win.
The following options are supported in .tf_wrapper
:
configure_backend: True # If true, automatically configure Terraform backends.
backend_check: True # If true, require this directory to have a terraform backend configured
envvars:
<NAME_OF_ENVVAR>:
source: # The source of the envvar. One of `['ssm', 'text', 'unset']`.
path: # If the source of the envvar is `ssm`, the SSM Parameter Store path to lookup the value of the environment variable from.
value: # if the source of the envvar is `text`, the string value to set as the environment variable.
# If the source is unset, any previous value for the environment variable is removed and the environment variable will not be set.
plugins:
<NAME_OF_PLUGIN>: <plugin url>
Terrawrap supports automatically downloading provider plugins by configuring the .tf_wrapper
file as specified above.
This is a temporary workaround until Terraform 0.13 is released with built-in support for automatically
downloading plugins and plugin registries are available for hosting private plugins.
Terrawrap will first try to download platform specific versions of plugins by downloading them from
<plugin url>/<system type>/<architecture type>
. If Terrawrap is unable to download from the platform specific URL
then it will try to download directly from the given plugin url directly instead.
For example, the following config on a Mac
plugins:
foo: http://example.com/foo
Terrawap will first try to download from http://example.com/foo/Darwin/x86_64
.
If that request fails then Terrawrap will try http://example.com/foo
instead.
Terrawrap automatically adds -var-file
arguments to any terraform command by scanning for *.auto.tfvars
files in the directory structure.
For example, the following command tf config/foo/bar apply
with the following directory structure:
config
├── foo
| └── bar
| │ ├── baz.tf
| │ └── bar.auto.tfvars
| └── foo.auto.tfvars
└── config.auto.tfvars
will generate the following command:
terraform apply -var-file config/config.auto.tfvars \
-var-file config/foo/foo.auto.tfvars \
-var-file config/foo/bar/bar.auto.tfvars
Terrawrap supports automatically configuring backends by injecting the appropriate -backend-config
args when running init
For example, the Terrawrap command tf config/foo/bar init
will generate a Terraform command like below if using
an AWS S3 remote state backend
terraform init -reconfigure \
-backend-config=dynamodb_table=<lock table name> \
-backend-config=encrypt=true \
-backend-config=key=config/foo/bar.tfstate \
-backend-config=region=<region name> \
-backend-config=bucket=<state bucket name> \
-backend-config=skip_region_validation=true \
-backend-config=skip_credentials_validation=true
Terrawrap configures the backend by looking for .tf_wrapper
files in the directory structure.
Either s3
or gcs
are supported. See the relevant Terraform documentation for the options available
for each type of backend:
https://www.terraform.io/docs/backends/types/s3.html#configuration-variables
https://www.terraform.io/docs/backends/types/gcs.html#configuration-variables
backends:
s3:
region:
role_arn:
bucket:
dynamodb_table:
Option Name | Required | Purpose |
---|---|---|
bucket | Yes | Name of S3 Bucket |
region | Yes | AWS Region that S3 state bucket and DynamoDB lock table are located in |
dynamodb_table | No | DynamoDB table to use for state locking. Locking is disable if lock_table is not set |
role_arn | No | AWS role to assume when reading/writing to S3 bucket and lock table |
The S3 state file key name is generated from the directory name being used to run the terraform command.
For example, tf config/foo/bar init
uses a state file with the key config/foo/bar.tfstate
in S3
backends:
gcs:
bucket:
Option Name | Required | Purpose |
---|---|---|
bucket | Yes | Name of GCS Bucket |
tf <directory> <terraform command>
runs a terraform command for a given directory that contains *.tf
files.
Terrawrap automatically includes autovars as described above when running the given command. Any Terraform
command is supported
plan_check <directory>
runs terraform plan
recursively for all child directories starting at the given directory.
plan_check
uses git
to identify which files have changed compared with the master
branch. It will then run plan
on any directory that contains tf
files with the following criteria
- A directory that has files that changed
- A directory that is symlinked to a directory that has files changed
- A directory with symlinked files that are linked to files that changed
- A directory that that uses a Terraform module whose source changed
- A directory with Terraform files that refer to an autovar file that changed
backend_check [directory]
verifies that all directories under the given directory that contain .tf
files
also have Terraform Backends defined.