Server Adapters

mokup/server/node bundles the Node adapters and dev server helpers. Use mokup/server/worker for Workers or mokup/server/fetch for runtime-agnostic fetch handlers.

Fetch server (Node)

Use cases:

• Start a standalone mock server from local mock files.
• Embed a fetch-capable mock server inside another Node process.

Demo:

import { createFetchServer, serve } from 'mokup/server/node'

const app = await createFetchServer({
  entries: { dir: 'mock' },
  playground: false,
})
serve({ fetch: app.fetch, port: 3000 })

You can call app.fetch directly:

Use cases:

• Call the mock server from tests or other server logic without binding a port.

Demo:

const response = await app.fetch(new Request('http://localhost/api/users'))

Options

Use cases:

• Provide moduleMap/moduleBase when running in a sandboxed runtime.
• Choose onNotFound: 'response' for a standalone fetch handler that should return 404.

export interface ServerOptions {
  manifest: Manifest | (() => Promise<Manifest>)
  moduleBase?: string | URL
  moduleMap?: Record<string, Record<string, unknown>>
  onNotFound?: 'next' | 'response'
}

onNotFound defaults to 'next'. Use 'response' to return 404 instead of falling through.

The Hono adapter runs anywhere Hono can run. Use the Worker entry for Cloudflare Workers.

Demo:

import type { ServerOptions } from 'mokup/server'
import mokupBundle from './.mokup/mokup.bundle.mjs'

const options: ServerOptions = {
  manifest: mokupBundle.manifest,
  moduleMap: mokupBundle.moduleMap,
  moduleBase: mokupBundle.moduleBase,
  onNotFound: 'response',
}

Prepare manifest

You can load the CLI build output directly:

pnpm

pnpm exec mokup build --dir mock --out .mokup

npm

npm exec mokup build --dir mock --out .mokup

yarn

yarn mokup build --dir mock --out .mokup

bun

bunx mokup build --dir mock --out .mokup

import mokupBundle from './.mokup/mokup.bundle.mjs'

const options = {
  manifest: mokupBundle.manifest,
  moduleMap: mokupBundle.moduleMap,
  moduleBase: mokupBundle.moduleBase,
}

Pass options to any adapter below. For brevity, the examples use manifest directly.

Express

Use cases:

• Add mock routes into an existing Express app.
• Reuse the same manifest across multiple Express instances.

Demo:

import { createExpressMiddleware } from 'mokup/server/node'

app.use(createExpressMiddleware({ manifest }))

Connect

Use cases:

• Add mocks to a Connect-based stack or legacy middleware chain.

Demo:

import { createConnectMiddleware } from 'mokup/server/node'

app.use(createConnectMiddleware({ manifest }))

Koa

Use cases:

• Inject mock routes into a Koa server without rewriting handlers.

Demo:

import { createKoaMiddleware } from 'mokup/server/node'

app.use(createKoaMiddleware({ manifest }))

Hono

Use cases:

• Mount Mokup inside a Hono app running on Node or edge runtimes.

Demo:

import { createHonoMiddleware } from 'mokup/server/node'

app.use(createHonoMiddleware({ manifest }))

Fastify

Use cases:

• Plug Mokup into a Fastify server with the standard plugin API.

Demo:

import { createFastifyPlugin } from 'mokup/server/node'

await app.register(createFastifyPlugin({ manifest }))

Fetch / Worker

Use cases:

• Build a runtime-agnostic fetch handler (Workers, edge, custom servers).
• Combine Mokup routes with your own routing logic.

Demo:

import { createFetchHandler } from 'mokup/server/fetch'

const handler = createFetchHandler({ manifest })
const response = await handler(new Request('https://example.com/api'))

Worker entry

For Workers (including Cloudflare Workers), use the helper entry. It wraps createFetchHandler from mokup/server/fetch and returns a 404 response when the handler yields null:

Use cases:

• Deploy Mokup to Cloudflare Workers with the smallest entry file.
• Avoid manual 404 handling when the mock handler returns null.

Demo:

import { createMokupWorker } from 'mokup/server/worker'
import mokupBundle from 'virtual:mokup-bundle'

export default createMokupWorker(mokupBundle)