env-cmd

A simple node program for executing commands using an environment from an env file.

💾 Install

npm install env-cmd or npm install -g env-cmd

⌨️ Basic Usage

Environment file ./.env

# This is a comment
ENV1=THANKS
ENV2=FOR ALL
ENV3=THE FISH

Package.json

{
  "scripts": {
    "test": "env-cmd mocha -R spec"
  }
}

Terminal

./node_modules/.bin/env-cmd node index.js

Using custom env file path

To use a custom env filename or path, pass the -f flag. This is a major breaking change from prior versions < 9.0.0

Terminal

./node_modules/.bin/env-cmd -f ./custom/path/.env node index.js

📜 Help

Usage: _ [options] <command> [...args]

Options:
  -v, --version                       output the version number
  -e, --environments [env1,env2,...]  The rc file environment(s) to use
  -f, --file [path]                   Custom env file path (default path: ./.env)
  --fallback                          Fallback to default env file path, if custom env file path not found
  --no-override                       Do not override existing environment variables
  -r, --rc-file [path]                Custom rc file path (default path: ./.env-cmdrc(|.js|.json)
  --silent                            Ignore any env-cmd errors and only fail on executed program failure.
  --use-shell                         Execute the command in a new shell with the given environment
  --verbose                           Print helpful debugging information
  -x, --expand-envs                   Replace $var in args and command with environment variables
  -h, --help                          output usage information

🔬 Advanced Usage

`.rc` file usage

For more complex projects, a .env-cmdrc file can be defined in the root directory and supports as many environments as you want. Simply use the -e flag and provide which environments you wish to use from the .env-cmdrc file. Using multiple environment names will merge the environment variables together. Later environments overwrite earlier ones in the list if conflicting environment variables are found.

.rc file ./.env-cmdrc

{
  "development": {
    "ENV1": "Thanks",
    "ENV2": "For All"
  },
  "test": {
    "ENV1": "No Thanks",
    "ENV3": "!"
  },
  "production": {
    "ENV1": "The Fish"
  }
}

Terminal

./node_modules/.bin/env-cmd -e production node index.js
# Or for multiple environments (where `production` vars override `test` vars,
# but both are included)
./node_modules/.bin/env-cmd -e test,production node index.js

`--no-override` option

Prevents overriding of existing environment variables on process.env and within the current environment.

`--fallback` file usage option

If the .env file does not exist at the provided custom path, then use the default fallback location ./.env env file instead.

`--use-shell`

Executes the command within a new shell environment. This is useful if you want to string multiple commands together that share the same environment variables.

Terminal

./node_modules/.bin/env-cmd -f ./test/.env --use-shell "npm run lint && npm test"

Asynchronous env file support

EnvCmd supports reading from asynchronous .env files. Instead of using a .env file, pass in a .js file that exports either an object or a Promise resolving to an object ({ ENV_VAR_NAME: value, ... }). Asynchronous .rc files are also supported using .js file extension and resolving to an object with top level environment names ({ production: { ENV_VAR_NAME: value, ... } }).

Terminal

./node_modules/.bin/env-cmd -f ./async-file.js node index.js

`-x` expands vars in arguments

EnvCmd supports expanding $var values passed in as arguments to the command. The allows a user to provide arguments to a command that are based on environment variable values at runtime.

Terminal

# $USER will be expanded into the env value it contains at runtime
./node_modules/.bin/env-cmd -x node index.js --user=$USER

`--silent` suppresses env-cmd errors

EnvCmd supports the --silent flag the suppresses all errors generated by env-cmd while leaving errors generated by the child process and cli signals still usable. This flag is primarily used to allow env-cmd to run in environments where the .env file might not be present, but still execute the child process without failing due to a missing file.

💿 Examples

You can find examples of how to use the various options above by visiting the examples repo env-cmd-examples.

💽️ Environment File Formats

These are the currently accepted environment file formats. If any other formats are desired please create an issue.

.env as key=value
.env.json Key/value pairs as JSON
.env.js JavaScript file exporting an object or a Promise that resolves to an object
.env-cmdrc as valid json or .env-cmdrc.json in execution directory with at least one environment { "dev": { "key1": "val1" } }
.env-cmdrc.js JavaScript file exporting an object or a Promise that resolves to an object that contains at least one environment

🗂 Path Rules

This lib attempts to follow standard bash path rules. The rules are as followed:

Home Directory = /Users/test

Working Directory = /Users/test/Development/app

Type	Input Path	Expanded Path
Absolute	`/some/absolute/path.env`	`/some/absolute/path.env`
Home Directory with `~`	`~/starts/on/homedir/path.env`	`/Users/test/starts/on/homedir/path.env`
Relative	`./some/relative/path.env` or `some/relative/path.env`	`/Users/test/Development/app/some/relative/path.env`
Relative with parent dir	`../some/relative/path.env`	`/Users/test/Development/some/relative/path.env`

🛠 API Usage

`EnvCmd`

A function that executes a given command in a new child process with the given environment and options

options { object }
- command { string }: The command to execute (node, mocha, ...)
- commandArgs { string[] }: List of arguments to pass to the command (['-R', 'Spec'])
- envFile { object }
  - filePath { string }: Custom path to .env file to read from (defaults to: ./.env)
  - fallback { boolean }: Should fall back to default ./.env file if custom path does not exist
- rc { object }
  - environments { string[] }: List of environment to read from the .rc file
  - filePath { string }: Custom path to the .rc file (defaults to: ./.env-cmdrc(|.js|.json))
- options { object }
  - expandEnvs { boolean }: Expand $var values passed to commandArgs (default: false)
  - noOverride { boolean }: Prevent .env file vars from overriding existing process.env vars (default: false)
  - silent { boolean }: Ignore any errors thrown by env-cmd, used to ignore missing file errors (default: false)
  - useShell { boolean }: Runs command inside a new shell instance (default: false)
  - verbose { boolean }: Prints extra debug logs to console.info (default: false)
- Returns { Promise<object> }: key is env var name and value is the env var value

`GetEnvVars`

A function that parses environment variables from a .env or a .rc file

options { object }
- envFile { object }
  - filePath { string }: Custom path to .env file to read from (defaults to: ./.env)
  - fallback { boolean }: Should fall back to default ./.env file if custom path does not exist
- rc { object }
  - environments { string[] }: List of environment to read from the .rc file
  - filePath { string }: Custom path to the .rc file (defaults to: ./.env-cmdrc(|.js|.json))
- verbose { boolean }: Prints extra debug logs to console.info (default: false)
Returns { Promise<object> }: key is env var name and value is the env var value

🧙 Why

Because sometimes it is just too cumbersome passing a lot of environment variables to scripts. It is usually just easier to have a file with all the vars in them, especially for development and testing.

🚨Do not commit sensitive environment data to a public git repo! 🚨

🧬 Related Projects

cross-env - Cross platform setting of environment scripts

🎊 Special Thanks

Special thanks to cross-env for inspiration (uses the same cross-spawn lib underneath too).

📋 Contributing Guide

I welcome all pull requests. Please make sure you add appropriate test cases for any features added. Before opening a PR please make sure to run the following scripts:

npm run lint checks for code errors and format according to ts-standard
npm test make sure all tests pass
npm run test-cover make sure the coverage has not decreased from current master

Current Tags

10.1.0 ... latest (5 years ago)

env-cmd

💾 Install

⌨️ Basic Usage

Using custom env file path

📜 Help

🔬 Advanced Usage

.rc file usage

--no-override option

--fallback file usage option

--use-shell

Asynchronous env file support

-x expands vars in arguments

--silent suppresses env-cmd errors

💿 Examples

💽️ Environment File Formats

🗂 Path Rules

🛠 API Usage

EnvCmd

GetEnvVars

🧙 Why

🧬 Related Projects

🎊 Special Thanks

📋 Contributing Guide

Current Tags

21 Versions

`.rc` file usage

`--no-override` option

`--fallback` file usage option

`--use-shell`

`-x` expands vars in arguments

`--silent` suppresses env-cmd errors

`EnvCmd`

`GetEnvVars`