Simple Node.js Environment Variable Parser

A simple Node.js package (written in TypeScript) containing a set of convenience functions that can be used for retrieving environment variables and casting them into specific types.

Official repository: github.com/BB-301/node-env-var-parser

How to install: npm install --save @bb301/env-var-parser

A quick example

Let's say that we have the following environment variables file:

# The port on which the server should be listening.
SERVER_PORT=20080

# Whether logging should be enabled for requests received
# by the server.
SERVER_LOGGING_ENABLED=true

The following code snippet illustrates a simple Express server, written in TypeScript, in which we make use of three library functions, namely asInteger, asOptionalString, and asBoolean, to respectively retrieve the SERVER_PORT, SERVER_HOSTNAME, and SERVER_LOGGING_ENABLED environment variables:

import { EnvVar } from "@bb301/env-var-parser";
import express from "express";
import morgan from "morgan";

const PORT: number = EnvVar.asInteger("SERVER_PORT");
const HOSTNAME: string = EnvVar.asOptionalString("SERVER_HOSTNAME") ?? "127.0.0.1";
const LOGGING_ENABLED: boolean = EnvVar.asBoolean("SERVER_LOGGING_ENABLED");

const app = express();

if (LOGGING_ENABLED) {
    app.use(morgan("common"));
}

app.get("/", (_, res) => {
    res.send("Hello, Simple Node.js Environment Variable Parser!");
});

app.listen(PORT, HOSTNAME, () => {
    console.log(`Express server listening at 'http://${HOSTNAME}:${PORT}'...`);
});

Please check out this project's official documentation website for a full API description. Alternatively, you may simply read the documentation from the source.

A note about integers and floats

The functions for parsing string-based environment variables into integers and floats are based on JavaScript's Number.parseInt and Number.parseFloat, respectively. That means, for instance, that calling EnvVar.asInteger on an environment variable whose value is 123_test will yield 123 (in other words, it won't fail, as one could expect).

Contact

If you have any questions, if you find bugs, or if you have suggestions for this project, please feel free to contact me by opening an issue on the repository.

License

This project is released under the MIT License.

Copyright

Copyright (c) 2024 BB-301 ([email protected])