Function createDevProxyApp

packages/dev-proxy/src/server.ts:239–282

(options: CreateDevProxyAppOptions)

}

export const createDevProxyApp = (options: CreateDevProxyAppOptions) => {
  const app = new HonoApp()
  const fetchImpl = options.fetchImpl || globalThis.fetch
  const logger = options.logger || console
  const allowedOrigins = options.cors?.allowedOrigins || 'local'

  app.onError((error, context) => {
    logger.error('[dev-proxy]', error)

    const headers = new Headers()
    applyCorsHeaders(headers, context.req.header('origin'), allowedOrigins)

    return new Response('Upstream proxy request failed.', {
      status: 502,
      headers,
    })
  })

  app.use('*', async (context, next) => {
    if (context.req.method === 'OPTIONS') {
      const headers = new Headers()
      applyCorsHeaders(headers, context.req.header('origin'), allowedOrigins)
      headers.set('Access-Control-Allow-Methods', ALLOW_METHODS)
      headers.set(
        'Access-Control-Allow-Headers',
        context.req.header('Access-Control-Request-Headers') || DEFAULT_ALLOW_HEADERS,
      )
      if (context.req.header('Access-Control-Request-Private-Network') === 'true')
        headers.set('Access-Control-Allow-Private-Network', 'true')

      return new Response(null, {
        status: 204,
        headers,
      })
    }

    await next()
    applyCorsHeaders(context.res.headers, context.req.header('origin'), allowedOrigins)
  })

  registerProxyRoutes(app, options.routes, fetchImpl, allowedOrigins)

  return app
}