Vafast Docs

Installation ​

Install ​

bash
npm install @vafast/api-client
bash
pnpm add @vafast/api-client
bash
yarn add @vafast/api-client
bash
bun add @vafast/api-client

Requirements ​

  • Node.js 18+ / Bun 1+ / modern browsers (Chrome 88+, Firefox 85+, Safari 14+, Edge 88+)
  • TypeScript 5+ (recommended)

Quick Check ​

typescript
import { createClient, eden } from '@vafast/api-client'

// In real projects, generate types with the CLI or define the contract yourself
type Api = {
  users: {
    get: { query?: { page?: number }; return: { users: string[] } }
  }
}

const api = eden<Api>(createClient('http://localhost:3000'))

const { data, error } = await api.users.get({ page: 1 })

if (error) {
  console.error(`${error.code}: ${error.message}`)
} else {
  console.log(data.users)
}

When your backend is Vafast, generate a type-safe client with the CLI:

bash
npx vafast sync --url http://localhost:3000 --out src/api.generated.ts
typescript
import { createClient } from '@vafast/api-client'
import { createApiClient } from './api.generated'

const api = createApiClient(createClient({ baseURL: '/api', timeout: 30_000 }))

const { data, error } = await api.users.get()
if (error) return
console.log(data)

See CLI Tool for details.

Environment Variables ​

typescript
import { createClient, eden } from '@vafast/api-client'

const client = createClient({
  baseURL: import.meta.env.VITE_API_BASE_URL ?? 'http://localhost:3000',
  timeout: Number(import.meta.env.VITE_API_TIMEOUT ?? 30_000),
})

Next Steps ​

  • Basic Usage — chained calls, error handling, middleware
  • Advanced Usage — multi-tenancy, refresh queues, multiple services
  • Overview — feature overview and SSE
  • Testing — test the client with server.fetch / mocks