Typesafe environment variables for NestJS using Zod.
npm install nestenv- Define your environment schema:
// src/config/env.ts
import { createNestEnvValidator, createTypedConfigService, z } from "nestenv";
const envSchema = z.object({
NODE_ENV: z
.enum(["development", "production", "test"])
.default("development"),
PORT: z.string().transform(Number).pipe(z.number().positive()),
DATABASE_URL: z.string().url(),
// Add other environment variables as needed
});
export const validateEnv = createNestEnvValidator(envSchema);
export type Env = z.infer<typeof envSchema>;
export type TypedConfigService = ReturnType<
typeof createTypedConfigService<typeof envSchema>
>;- Use the validator in your main module:
// src/app.module.ts
import { Module } from "@nestjs/common";
import { ConfigModule } from "@nestjs/config";
import { validateEnv } from "./env";
@Module({
imports: [
ConfigModule.forRoot({
validate: validateEnv,
isGlobal: true,
}),
// Other modules...
],
// ...
})
export class AppModule {}- Inject and use the typed ConfigService in your services:
// src/some.service.ts
import { Injectable } from "@nestjs/common";
import { ConfigService } from "@nestjs/config";
import { TypedConfigService } from "./env";
@Injectable()
export class SomeService {
constructor(private configService: TypedConfigService) {}
someMethod() {
const port = this.configService.get("PORT");
const databaseUrl = this.configService.get("DATABASE_URL");
// These will be correctly typed based on your schema
}
}- Runtime validation of environment variables
- Type-safe access to environment variables through the
ConfigService - Automatic throwing of errors if required environment variables are missing or invalid
- Leverages Zod for powerful schema validation
Creates a validator function for NestJS's ConfigModule based on a Zod schema.
Creates a typed ConfigService based on your Zod schema.
MIT