Env Config Zod

A simply utility to parse environment variables into config objects using Zod.

Installation

npm

npm i env-config-zod zod

pnpm

pnpm add env-config-zod zod

Please note that zod is just a peer dependency of this library and is installed separately.

Usage

Simply import the config parser and supply it with a schema:

import {parseEnvConfig} from "env-config-zod";

const envConfig = parseEnvConfig({
    database: {
        hostname: z.string().min(1),
        port: z.coerce.number.int().min(1).max(65_535),
        username: z.string().min(1),
        password: z.string().min(1),
    },
});

The parsed env config will have proper resolved TypeScript types for you. The above config would parse the following environment variables:

• DATABASE_HOSTNAME
• DATABASE_PORT
• DATABASE_USERNAME
• DATABASE_PASSWORD

Case conversion

While parsing, this library converts any object key to "CONSTANT_CASE" in order to read from the environment. It doesn't matter whether you use camelCase, PascalCase or anything else for your property names.

Custom prefix

If you want to prefix all your environment variables to avoid collisions with other things, you can pass a prefix as the second parameter to parseEnvConfig, e.g. APP_.

Helpers schemas

Parsing specific types can be repetitive when defining a config schema. Thus, this library exports common schemas:

Boolean schema

You can use booleanSchema in order to parse any boolean values. Any value matching the string "true" or "1" (case-insensitive) will evaluate to true, anything else will evaluate to false.

Schema safety

The type definition of EnvConfigSchema makes sure that you only pass in Zod schemas which accept strings as input. Thus, you cannot pass types which would always fail validation, like z.number().