Environment Variable Validation

Using a schema validation library like valibot lets you validate if all environment variables required for the application are set correctly.

Since Nuxt reads environment variables at build time from the local .env file, you can validate them in a prepare script. This ensures your build fails early if required configuration is missing, preventing deployment of misconfigured applications in CI/CD pipelines.

server.prepare.ts

import { defineNuxtPrepareHandler } from 'nuxt-prepare/config'
import * as v from 'valibot'

export default defineNuxtPrepareHandler(() => {
  const schema = v.object({
    NUXT_PUBLIC_FOO: v.pipe(v.string(), v.nonEmpty()),
  })

  const result = v.safeParse(schema, process.env)

  if (!result.success) {
    console.error(
      `Missing environment variables:\n${result.issues
        .filter(issue => issue.path != null)
        .map(issue => `  - ${issue.path![0].key}: ${issue.message}`)
        .join('\n')}`,
    )
  }

  return {
    ok: result.success,
  }
})