envgen

envgen is CLI tool that generates .env files for subpackages in your project based on a configuration file.

The purpose of this tool is to:

• avoid using a bash script: harder to maintain, test, lacks the safety of a statically typed and compiled language like Go;
• provide flexibility and ease of use/reuse: additional features can be easily added and made available to projects already using the tool.

Usage

$ envgen <vars config file> [env file 1] ... [env file N]

$ envgen config.yaml will read vars already available in the environment

$ envgen config.yaml .part.env .pck.env will read vars already available in the environment and will load vars from the passed files

Here's the structure of the configuration file:

branchVarName: CIRCLE_BRANCH
branchVarDefault: develop

branches:
  - name: develop
    suffix: _DEV
  - name: staging
    suffix: _STG

packages:
  - package: awesome-crawler
    envFile: .crawler.env
    variables:
      - AC_THRESHOLD
      - AC_TITLE
  - package: web-server/api
    variables:
      - WS_PORT
      - WS_ADDRESS

globals:
  - V_DATABASE

Configuration details:

Key	Description
branchVarName	name of the env var that contains the CI branch (CIRCLE_BRANCH), for CircleCI
branchVarDefault	default value of branchVarName (optional, defaults to "develop")
branches	list of branches and their suffixes
packages	list of subpackages
packages.envFile	name of the env file to be created (optional)
packages.package	subpackage path to where the .env file will be written
packages.variables	subpackage environment variables to generate
globals	list of variables that are environment independent and global to all subpackages

For each entry in the packages array, a .env file will be created in the path package, with the variables defined in variables and globals.

Example:

Project structure:

├── bla.go 
├── awesome-crawler/
│   └── index.js
└── web-server/
  └── api/
    └── index.html

Loaded env vars:

CIRCLE_BRANCH=develop
V_DATABASE=somedburl
WS_ADDRESS_DEV=www.sample.web
WS_PORT_DEV=1234
AC_TITLE_DEV=sometitle 
AC_THRESHOLD_DEV=50

Resulting structure:

├── bla.go 
├── awesome-crawler
│   ├── .crawler.env
│   └── index.js
└── web-server
  └── api/
    ├── .env
    └── index.html

Content of awesome-crawler/.crawler.env:

V_DATABASE=somedburl
AC_TITLE=sometitle
AC_THRESHOLD=50

Content of web-server/.env:

V_DATABASE=somedburl
WS_ADDRESS=www.sample.web
WS_PORT=1234