languageDetector

Kind: Function

Source: src/middleware/language/language.ts

Part of: Middleware

Language detector middleware factory

languageDetector creates middleware that determines the language for an incoming request. Register it early in the middleware pipeline so downstream handlers can use the detected language context.

Signature

ts
function languageDetector(userOptions: Partial<DetectorOptions>): MiddlewareHandler

Parameters

Returns: MiddlewareHandler

Diagram

mermaid
graph LR
  Request[Incoming request] --> Detector[languageDetector middleware]
  Detector --> Language[Detected language context]
  Language --> Handler[Downstream handler]

Usage

ts
import { languageDetector } from './middleware/language/language';

const app = createApp();

app.use(languageDetector());

// Routes registered after the detector can access language-aware context.
app.get('/content', contentHandler);

AI Coding Instructions

• Register languageDetector() before routes or middleware that depend on request language context.
• Keep language lookup behavior aligned with the application's translation and locale handling.
• Do not create detector middleware inside individual route handlers.
• Test requests with missing or unsupported language inputs alongside supported language inputs.