Azure-Env-Safe

A zero-dependency lightweight environment variable checker for azure functions written in Javascript/Typescript.

Installation

npm install --save azure-env-safe

Why

Inspired by dotenv-safe, it's a good practice to keep your config separate from your application. It is also a good practice to fail early and with good error messages to help debugging. This approach will help you avoid having random error messages from appearing because an environment variable is missing and only finding it at runtime once your application is deployed. dotenv-safe requires a .env.example file, so if you were to use it with an azure function, then you would have both a local.settings.example.json and a .env.example where your env variables could go. Rather than having a confusing situation like that with 2 example files, this repo just uses your local.settings.example.json file the same way that dotenv-safe works.

How

This package will find your application's local.settings.example.json and verify that the environment variables in your app. If any environment variables are missing, a descriptive error will be thrown telling you which environment variables are missing.

Usage

Let's say you have a project like this

my-func/index.js
local.settings.json
local.settings.example.json

In my-func/index.js add this code to the very top of the file:

require('azure-env-safe/config');

This will find the the local.settings.example.json in your project and assert that the environment variables exist.

Config

You can pass additional options to configure this library.

require('azure-env-safe').config({
    example: './.my-env-example-filename.json'
});

example

Default: local.settings.example.json.

Path to the example json file.