feat: add utility for router params (#120) (#158)

README.md

@@ -121,6 +121,7 @@ Instead of adding helpers to `req` and `res`, h3 exposes them as composable util
 - `setCookie(res, name, value, opts?)`
 - `deleteCookie(res, name, opts?)`
 - `useQuery(req)`
+- `getRouterParams(event)`
 - `send(res, data, type?)`
 - `sendRedirect(res, location, code=302)`
 - `getRequestHeaders(event, headers)` (alias: `getHeaders`)

src/utils/request.ts

@@ -10,6 +10,17 @@ export function getQuery (event: CompatibilityEvent) {
 /** @deprecated Use `h3.getQuery` */
 export const useQuery = getQuery
 
+export function getRouterParams (event: CompatibilityEvent): CompatibilityEvent['context'] {
+  // Fallback object needs to be returned in case router is not used (#149)
+  return event.context.params || {}
+}
+
+export function getRouterParam (event: CompatibilityEvent, name: string): CompatibilityEvent['context'][string] {
+  const params = getRouterParams(event)
+
+  return params[name]
+}
+
 export function getMethod (event: CompatibilityEvent, defaultMethod: HTTPMethod = 'GET'): HTTPMethod {
   return (event.req.method || defaultMethod).toUpperCase() as HTTPMethod
 }

test/router.test.ts

@@ -1,6 +1,6 @@
 import supertest, { SuperTest, Test } from 'supertest'
 import { describe, it, expect, beforeEach } from 'vitest'
-import { createApp, createRouter, App, Router } from '../src'
+import { createApp, createRouter, App, Router, getRouterParams, getRouterParam } from '../src'
 
 describe('router', () => {
   let app: App
@@ -61,3 +61,73 @@ describe('router', () => {
     expect(res.status).toEqual(405)
   })
 })
+
+describe('getRouterParams', () => {
+  let app: App
+  let request: SuperTest<Test>
+
+  beforeEach(() => {
+    app = createApp({ debug: false })
+    request = supertest(app)
+  })
+
+  describe('with router', () => {
+    it('can return router params', async () => {
+      const router = createRouter().get('/test/params/:name', (request) => {
+        expect(getRouterParams(request)).toMatchObject({ name: 'string' })
+        return '200'
+      })
+      app.use(router)
+      const result = await request.get('/test/params/string')
+
+      expect(result.text).toBe('200')
+    })
+  })
+
+  describe('without router', () => {
+    it('can return an empty object if router is not used', async () => {
+      app.use('/', (request) => {
+        expect(getRouterParams(request)).toMatchObject({})
+        return '200'
+      })
+      const result = await request.get('/test/empty/params')
+
+      expect(result.text).toBe('200')
+    })
+  })
+})
+
+describe('getRouterParam', () => {
+  let app: App
+  let request: SuperTest<Test>
+
+  beforeEach(() => {
+    app = createApp({ debug: false })
+    request = supertest(app)
+  })
+
+  describe('with router', () => {
+    it('can return a value of router params corresponding to the given name', async () => {
+      const router = createRouter().get('/test/params/:name', (request) => {
+        expect(getRouterParam(request, 'name')).toEqual('string')
+        return '200'
+      })
+      app.use(router)
+      const result = await request.get('/test/params/string')
+
+      expect(result.text).toBe('200')
+    })
+  })
+
+  describe('without router', () => {
+    it('can return `undefined` for any keys', async () => {
+      app.use('/', (request) => {
+        expect(getRouterParam(request, 'name')).toEqual(undefined)
+        return '200'
+      })
+      const result = await request.get('/test/empty/params')
+
+      expect(result.text).toBe('200')
+    })
+  })
+})