Validate and parse your environment variables like a responsible adult

Installation

Use your favourite package manager to install zodotenv:

npm i zodotenv

pnpm add zodotenv

bun add zodotenv

deno add npm:zodotenv

Usage

Define your configuration

import { z } from 'zod';
import { zodotenv } from 'zodotenv';

const config = zodotenv({
  name: ['NAME', z.string().default('my-app')],
  port: ['PORT', z.coerce.number().default(3000)],
  http2: ['HTTP2', z.string().transform((s) => s === 'true')],
  database: {
    host: ['DB_HOST', z.string()],
    driver: ['DB_DRIVER', z.enum(['mysql', 'pgsql', 'sqlite'])],
    tables: ['DB_TABLES', z.preprocess((s) => s.split(','), z.array(z.string()))],
  },
  credentials: {
    username: ['USERNAME', z.string()],
    password: ['PASSWORD', z.string(), { secret: true }],
  },
});

[!CAUTION] If the environment variable doesn’t match the Zod schema, zodotenv will throw an error. Simple as that.

Grab your values with config(...)

It returns the parsed and validated values including the inferred TypeScript types.

You can even dive into nested values using an object-path-style string, with autocompletion and TypeScript validation to help you out.

config('port'); // number
config('database.driver'); // 'mysql' | 'pgsql' | 'sqlite'
config('database.tables'); // string[]

config('something.which.does.not.exist');
// ^^^ TypeScript will call you out on this one

Serialise your configuration

You can serialise your entire configuration object to JSON. This is useful for logging or debugging purposes.

console.log(JSON.stringify(config, null, 2));

// or

console.log(config.toJSON());

[!TIP] Any configuration entries marked with { secret: true } will have their values masked when serialising to JSON, ensuring that sensitive information is not exposed.

Example

const config = zodotenv({
  port: ['PORT', z.coerce.number().default(3000)],
  database: {
    host: ['DB_HOST', z.string()],
    password: ['DB_PASSWORD', z.string(), { secret: true }],
  },
});

console.log(JSON.stringify(config, null, 2));
// Output:
//  {
//    "port": 3000,
//    "database.host": "localhost:5432",
//    "database.password": "*********"
//  }

Tips

Check out Zod schemas if you haven't already!

Since all environment variables are strings, you might need to use .coerce / .transform() / .preprocess() to convert them to the type you need:

// Boolean, e.g. `HTTP2=true`
z.string().transform((s) => s === 'true')

// Number, e.g. `PORT=3000`
z.coerce.number()

// Comma-separated list to string array, e.g. `DB_TABLES=users,posts` -> ["users", "posts"]
z.preprocess((v) => String(v).split(','), z.array(z.string()))

// JSON string to object, e.g. `CONFIG={"key":"value"}` -> {key: "value"}
z.string().transform((s) => JSON.parse(s)).pipe(
  z.object({ key: z.string() })
)