How to augment `proccess.env` as well from `createEnv` output.

[AhmedBaset]

Is there a way to augment NodeJS.ProccessEnv by extending the env object without rewriting them one by one.

I've tried:

export const env = createEnv({
  server: {
    DATABASE_URL: z.string().url(),
  },
  runtimeEnv: {
    DATABASE_URL: process.env.DATABASE_URL,
  },
});

export type Env = typeof env

// env.d.ts
import type {Env} from "@/env";

declare global {
  namespace NodeJS {
    interface ProcessEnv extends Env {}
  }
}

I get errors in:

• Env: Type alias 'Env' circularly references itself.ts(2456)
• env: 'env' implicitly has type 'any' because it does not have a type annotation and is referenced directly or indirectly in its own initializer.ts(7022);

[juliusmarminge]

i dont think this is possible, as the error suggests it creates a circular reference.

what's the use case why you wanna do this? I believe augmenting process.env here is kinda scary since we have no assurance if the type iss correct then considering transforms, default values etc aren't taken into account then.

e.g.:

export const env = createEnv({
  server: {
    DATABASE_URL: z.string().url().default("mysql://localhost:3306/db"),
  },
  runtimeEnv: {
    DATABASE_URL: process.env.DATABASE_URL,
  },
});

here env.DATABASE_URL will be guaranteed to be a string, but process.env.DATABASE_URL can be undefined. augmenting the type would potentailly cause a runtime error

[AhmedBaset]

Got it, thanks

It was a weird use case

going to close this