Recipes

nobara supports the full power of Valibot meaning you can use transforms, default values etc. to create a set of powerful and flexible validation schemas for your environment variables. Below we'll look at a few example recipes for

Booleans

Coercing booleans from strings is a common use case. Below are 2 examples of how to do this, but you can choose any coercian logic you want.

Valibot's default primitives coercion should not be used for booleans, since every string gets coerced to true.

import { custom, string, transform } from "valibot";

export const env = createEnv({
  server: {
    // transform to boolean using preferred coercion logic
    COERCED_BOOLEAN: transform(string(), (s) => s !== "false" && s !== "0"),

    // only allow "true" or "false"
    // transform to boolean
    ONLY_BOOLEAN: transform(
      string([custom((s) => s === "true" || s === "false")]),
      (s) => s === "true"
    ),
  },
  experimental__runtimeEnv: {},
});

Numbers

Coercing numbers from strings is another common use case.

import { coerce, number } from "valibot";

export const env = createEnv({
  server: {
    SOME_NUMBER: coerce(number(), Number),
  },
  // ...
});

Storybook

Storybook uses its own bundler, which is otherwise unaware of t3-env and won't call into runtimeEnv to ensure that the environment variables are present. You can use Storybook's support for defining environment variables separately to ensure that all environment variables are actually available for Storybook:

import { env as t3Env } from "~/env/client.mjs";

const config: StorybookConfig = {
  // other Storybook config...
  env: (config1) => ({
    ...config1,
    ...t3Env,
  }),
};

export default config;