feat: support runtime aginostic getAcceptLanguages

build.config.ts

@@ -5,5 +5,19 @@ export default defineBuildConfig({
   rollup: {
     emitCJS: true,
   },
-  entries: ['./src/index.ts'],
+  entries: [
+    {
+      input: './src/index.ts',
+    },
+    {
+      input: './src/h3.ts',
+    },
+    {
+      input: './src/node.ts',
+    },
+    {
+      input: './src/web.ts',
+    },
+  ],
+  externals: ['h3'],
 })

package.json

@@ -40,6 +40,21 @@
       "import": "./dist/index.mjs",
       "require": "./dist/index.cjs"
     },
+    "./h3": {
+      "types": "./dist/h3.d.ts",
+      "import": "./dist/h3.mjs",
+      "require": "./dist/h3.cjs"
+    },
+    "./node": {
+      "types": "./dist/node.d.ts",
+      "import": "./dist/node.mjs",
+      "require": "./dist/node.cjs"
+    },
+    "./web": {
+      "types": "./dist/web.d.ts",
+      "import": "./dist/web.mjs",
+      "require": "./dist/web.cjs"
+    },
     "./dist/*": "./dist/*",
     "./package.json": "./package.json"
   },
@@ -67,6 +82,7 @@
     "@vitest/coverage-v8": "^0.34.4",
     "bumpp": "^9.2.0",
     "gh-changelogen": "^0.2.8",
+    "h3": "^1.8.1",
     "lint-staged": "^14.0.0",
     "typescript": "^5.2.2",
     "unbuild": "^2.0.0",

src/h3.test.ts

@@ -0,0 +1,46 @@
+import { describe, expect, test } from 'vitest'
+import { getAcceptLanguages } from './h3.ts'
+
+import type { H3Event } from 'h3'
+
+describe('getAcceptLanguages', () => {
+  test('basic', () => {
+    const eventMock = {
+      node: {
+        req: {
+          method: 'GET',
+          headers: {
+            'accept-language': 'en-US,en;q=0.9,ja;q=0.8',
+          },
+        },
+      },
+    } as H3Event
+    expect(getAcceptLanguages(eventMock)).toEqual(['en-US', 'en', 'ja'])
+  })
+
+  test('any language', () => {
+    const eventMock = {
+      node: {
+        req: {
+          method: 'GET',
+          headers: {
+            'accept-language': '*',
+          },
+        },
+      },
+    } as H3Event
+    expect(getAcceptLanguages(eventMock)).toEqual([])
+  })
+
+  test('empty', () => {
+    const eventMock = {
+      node: {
+        req: {
+          method: 'GET',
+          headers: {},
+        },
+      },
+    } as H3Event
+    expect(getAcceptLanguages(eventMock)).toEqual([])
+  })
+})

src/h3.ts

@@ -0,0 +1,21 @@
+import { getAcceptLanguagesFromGetter } from './http.ts'
+import { getHeaders } from 'h3'
+
+import type { H3Event } from 'h3'
+
+/**
+ * get accpet languages
+ *
+ * @description parse `accept-language` header string
+ *
+ * @param {H3Event} event The {@link H3Event | H3} event
+ *
+ * @returns {Array<string>} The array of language tags, if `*` (any language) or empty string is detected, return an empty array.
+ */
+export function getAcceptLanguages(event: H3Event): string[] {
+  const getter = () => {
+    const headers = getHeaders(event)
+    return headers['accept-language']
+  }
+  return getAcceptLanguagesFromGetter(getter)
+}

src/http.ts

@@ -0,0 +1,8 @@
+import { parseAcceptLanguage } from './shared.ts'
+
+export function getAcceptLanguagesFromGetter(
+  getter: () => string | null | undefined,
+): string[] {
+  const acceptLanguage = getter()
+  return acceptLanguage ? parseAcceptLanguage(acceptLanguage) : []
+}

src/index.ts

@@ -1,43 +1 @@
-const objectToString = Object.prototype.toString
-const toTypeString = (value: unknown): string => objectToString.call(value)
-
-/**
- * check whether the value is a {@link Intl.Locale} instance
- *
- * @param {unknown} val The locale value
- *
- * @returns {boolean} Returns `true` if the value is a {@link Intl.Locale} instance, else `false`.
- */
-export function isLocale(val: unknown): val is Intl.Locale {
-  return toTypeString(val) === '[object Intl.Locale]'
-}
-
-/**
- * parse `accept-language` header string
- *
- * @param {string} value The accept-language header string
- *
- * @returns {Array<string>} The array of language tags, if `*` (any language) or empty string is detected, return an empty array.
- */
-export function parseAcceptLanguage(value: string): string[] {
-  return value.split(',').map((tag) => tag.split(';')[0]).filter((tag) =>
-    !(tag === '*' || tag === '')
-  )
-}
-
-/**
- * validate the language tag whether is a well-formed {@link https://datatracker.ietf.org/doc/html/rfc4646#section-2.1 | BCP 47 language tag}.
- *
- * @param {string} lang a language tag
- *
- * @returns {boolean} Returns `true` if the language tag is valid, else `false`.
- */
-export function validateLanguageTag(lang: string): boolean {
-  try {
-    // TODO: if we have a better way to validate the language tag, we should use it.
-    new Intl.Locale(lang)
-    return true
-  } catch {
-    return false
-  }
-}
+export * from './shared.ts'

src/node.test.ts

@@ -0,0 +1,30 @@
+import { describe, expect, test } from 'vitest'
+import { getAcceptLanguages } from './node.ts'
+import { IncomingMessage } from 'node:http'
+
+describe('getAcceptLanguages', () => {
+  test('basic', () => {
+    const mockRequest = {
+      headers: {
+        'accept-language': 'en-US,en;q=0.9,ja;q=0.8',
+      },
+    } as IncomingMessage
+    expect(getAcceptLanguages(mockRequest)).toEqual(['en-US', 'en', 'ja'])
+  })
+
+  test('any language', () => {
+    const mockRequest = {
+      headers: {
+        'accept-language': '*',
+      },
+    } as IncomingMessage
+    expect(getAcceptLanguages(mockRequest)).toEqual([])
+  })
+
+  test('empty', () => {
+    const mockRequest = {
+      headers: {},
+    } as IncomingMessage
+    expect(getAcceptLanguages(mockRequest)).toEqual([])
+  })
+})

src/node.ts

@@ -0,0 +1,16 @@
+import { IncomingMessage } from 'node:http'
+import { getAcceptLanguagesFromGetter } from './http.ts'
+
+/**
+ * get accpet languages
+ *
+ * @description parse `accept-language` header string
+ *
+ * @param {IncomingMessage} event The {@link IncomingMessage | request}
+ *
+ * @returns {Array<string>} The array of language tags, if `*` (any language) or empty string is detected, return an empty array.
+ */
+export function getAcceptLanguages(req: IncomingMessage) {
+  const getter = () => req.headers['accept-language']
+  return getAcceptLanguagesFromGetter(getter)
+}

test/index.test.ts → src/shared.test.ts

@@ -1,9 +1,5 @@
 import { describe, expect, test } from 'vitest'
-import {
-  isLocale,
-  parseAcceptLanguage,
-  validateLanguageTag,
-} from '../src/index.ts'
+import { isLocale, parseAcceptLanguage, validateLanguageTag } from './shared.ts'
 
 describe('isLocale', () => {
   test('Locale instance', () => {

src/shared.ts

@@ -0,0 +1,43 @@
+const objectToString = Object.prototype.toString
+const toTypeString = (value: unknown): string => objectToString.call(value)
+
+/**
+ * check whether the value is a {@link Intl.Locale} instance
+ *
+ * @param {unknown} val The locale value
+ *
+ * @returns {boolean} Returns `true` if the value is a {@link Intl.Locale} instance, else `false`.
+ */
+export function isLocale(val: unknown): val is Intl.Locale {
+  return toTypeString(val) === '[object Intl.Locale]'
+}
+
+/**
+ * parse `accept-language` header string
+ *
+ * @param {string} value The accept-language header string
+ *
+ * @returns {Array<string>} The array of language tags, if `*` (any language) or empty string is detected, return an empty array.
+ */
+export function parseAcceptLanguage(value: string): string[] {
+  return value.split(',').map((tag) => tag.split(';')[0]).filter((tag) =>
+    !(tag === '*' || tag === '')
+  )
+}
+
+/**
+ * validate the language tag whether is a well-formed {@link https://datatracker.ietf.org/doc/html/rfc4646#section-2.1 | BCP 47 language tag}.
+ *
+ * @param {string} lang a language tag
+ *
+ * @returns {boolean} Returns `true` if the language tag is valid, else `false`.
+ */
+export function validateLanguageTag(lang: string): boolean {
+  try {
+    // TODO: if we have a better way to validate the language tag, we should use it.
+    new Intl.Locale(lang)
+    return true
+  } catch {
+    return false
+  }
+}

src/web.test.ts

@@ -0,0 +1,21 @@
+import { describe, expect, test } from 'vitest'
+import { getAcceptLanguages } from './web.ts'
+
+describe('getAcceptLanguages', () => {
+  test('basic', () => {
+    const mockRequest = new Request('https://example.com')
+    mockRequest.headers.set('accept-language', 'en-US,en;q=0.9,ja;q=0.8')
+    expect(getAcceptLanguages(mockRequest)).toEqual(['en-US', 'en', 'ja'])
+  })
+
+  test('any language', () => {
+    const mockRequest = new Request('https://example.com')
+    mockRequest.headers.set('accept-language', '*')
+    expect(getAcceptLanguages(mockRequest)).toEqual([])
+  })
+
+  test('empty', () => {
+    const mockRequest = new Request('https://example.com')
+    expect(getAcceptLanguages(mockRequest)).toEqual([])
+  })
+})

src/web.ts

@@ -0,0 +1,15 @@
+import { getAcceptLanguagesFromGetter } from './http.ts'
+
+/**
+ * get accpet languages
+ *
+ * @description parse `accept-language` header string
+ *
+ * @param {Request} event The {@link Request | request}
+ *
+ * @returns {Array<string>} The array of language tags, if `*` (any language) or empty string is detected, return an empty array.
+ */
+export function getAcceptLanguages(req: Request) {
+  const getter = () => req.headers.get('accept-language')
+  return getAcceptLanguagesFromGetter(getter)
+}