ntcw

NTCW (Node Terraform CLI Wrapper)

A Node.js wrapper for Terraform's command line interface.

ntcw runs the terraform CLI commands isolated via Node's child_process, thus why changing the environment variable TF_LOG, according to the debug log level, won't affect the environment variable you've set up for your main terminal session.

TOC

• Installation
  • Requirements
  • Dependencies
• Run the CLI wrapper
  • Directory watcher
  • Examples
  • Argument abbreviations
  • Debugging
• References
• TODO

Installation

^TOC

npm i -g ntcw

You can also clone this repository and use NPM to link and make the script globally available. With a shebang in the index.js and the bin property in the package.json, this script is ready to go binary!

// Shebang
#!/usr/bin/env node

// Package.json binary def. tf
{
  ...
  "bin": {
    "tf": "src/index.js"
  }
}

Clone the repo and install the dependencies

git clone [e-mail]:bulletinmybeard/ntcw.git \
    && cd ntcw \
    && npm install

Use npm link to create the symlink to the script

npm link

Use npm unlink to remove the symlink to the script

npm unlink \
    ntcw

Make sure the binary symlink is gone for good!

rm -rf \
    /usr/local/bin/tf

Before: node ./src/index.js validate
After: ntcw validate

Requirements

^TOC

The script has been fully tested with the Terraform CLI in version 0.12.29 and Node.js in version 13.13.0. Mind you, Terraform CLI versions above 0.12.29 might won't work!

Dependencies

^TOC

I keep the source code as Vanilla as possible and only depend on a few Node core modules. However, the package.json contains the dev dependency @types/node for the IDE.

Run the CLI wrapper

ntcw validate

Directory watcher

^TOC

Running tthe CLI wrapper with the watch argument and without value will attach a watcher to the caller directory and triggers the given terraform command with all its arguments again whenever a change within the parent or nested directories was emitted. Passing a directory path to the watch argument will overwrite the default working directory to the given argument value. Useful witth the terraform command validate!

// Without path
ntcw validate -watch

// With relative path
ntcw validate -watch=./terraform

// With absolute path
ntcw validate -watch=/usr/local/dev/projects/terraform

Examples

^TOC

ntcw version
ntcw init
ntcw plan -compact-warnings
ntcw apply -error
ntcw apply -auto (-auto-approve)
ntcw validate -watch -trace
ntcw plan --help
...

Argument abbreviations

^TOC

For most of the terraform commands exists a short form of the name (e.g., ntcw plan -destroy). The argument auto-approve got the alias auto.

const SHORT_COMMAND_MAPPING = {
    a: 'apply',
    c: 'console',
    d: 'destroy',
    e: 'env',
    f: 'fmt',
    i: 'import',
    o: 'output',
    p: 'plan',
    r: 'refresh',
    s: 'show',
    t: 'taint',
    u: 'untaint',
    v: 'validate',
    w: 'workspace',
};

const SHORT_ARGUMENT_MAPPING = {
    auto: 'auto-approve',
};

ntcw p -compact-warnings
ntcw a -error
ntcw a -auto (-auto-approve)
ntcw v -watch -trace
ntcw p --help
ntcw a -auto
...

Debugging

^TOC

Debugging is done by passing one of the five supported arguments from below. The arguments represent the log levels for the environment variable TF_LOG (e.g., TF_LOG="trace").

ntcw validate -trace
ntcw validate -debug
ntcw validate -info
ntcw validate -warning
ntcw validate -error

References

^TOC

• Terraform
  • https://www.terraform.io/downloads.html
  • https://www.terraform.io/docs/commands/index.html
  • https://www.terraform.io/docs/internals/debugging.html
• Node.js
  • https://nodejs.org/api/fs.html
  • https://nodejs.org/api/path.html
  • https://nodejs.org/api/util.html
  • https://nodejs.org/api/child_process.html
• NPM
  • https://docs.npmjs.com/cli/v6/commands/npm-link

TODO

^TOC

• Refactor the watcher to use one or multiple glob patterns.
• Refactor the execModule and capture the stdout stream to replace all terraform command references with tf.