Add interceptors

Register handlers on client.interceptors.request, .response, or .error to apply behavior across calls. Handlers receive the resolved request and result objects.

Run before the send

Request handlers run after URL construction, serialization, and authentication. Return the modified request:

import { client } from './gen/.kubb/client'

client.interceptors.request.use((request) => {
  request.headers['X-Request-ID'] = crypto.randomUUID()
  return request
})

The handler receives a ResolvedRequest (url, method, headers, body, signal, credentials, options, responseType).

Run after the send

Response handlers run before calls resolve, and before the status split and deserialization, so data is the raw body. The handler receives a TransportResult (data, status, statusText, headers, contentType, request, response):

client.interceptors.response.use((result) => {
  console.info(`${result.status} ${result.request.url}`)
  return result
})

React to an error

Use an error handler to react to HTTP errors on the throwing path. The handler receives the ResponseError:

client.interceptors.error.use((error) => {
  if (error.status === 401) scheduleTokenRefresh()
  return error
})

This channel only fires on the throw path. When you read with throwOnError: false, a documented non-2xx response resolves and no error interceptor runs, so inspect the returned error on the result instead. A transport failure (no response) still throws. The error handler does not run, because there is no result to pass it.

Add, replace, and remove handlers

use registers a handler and returns an id. Pass that id to eject to remove it, or to update to swap its function in place.

const id = client.interceptors.request.use((request) => request)

client.interceptors.request.update(id, (request) => {
  request.headers['X-Trace'] = 'on'
  return request
})

client.interceptors.request.eject(id)

Where to set them

Register handlers on the shared client for all operations, or on a separate createClient instance for isolated calls. Interceptors are instance-level settings.

See also

• Handle errors
• Authenticate requests
• Use a custom transport