feat: support try locale getting APIs (#38)

README.md

@@ -146,6 +146,11 @@ You can do `import { ... } from '@intlify/utils'` the above utilities
 - `setCookieLocale`
 - `getPathLocale`
 - `getQueryLocale`
+- `tryHeaderLocales`
+- `tryHeaderLocale`
+- `tryCookieLocale`
+- `tryPathLocale`
+- `tryQueryLocale`
 
 The about utilies functions accpet Web APIs such as [Request](https://developer.mozilla.org/en-US/docs/Web/API/Request) and [Response](https://developer.mozilla.org/en-US/docs/Web/API/Response) that is supported by JS environments (such as Deno, Bun, and Browser)
 

deno/web.ts

@@ -111,6 +111,8 @@ export function getHeaderLanguage(
  * @param {HeaderOptions['name']} options.name The header name, which is as default `accept-language`.
  * @param {HeaderOptions['parser']} options.parser The parser function, which is as default {@link parseDefaultHeader}. If you are specifying more than one in your own format, you need a parser.
  *
+ * @throws {RangeError} Throws the {@link RangeError} if header are not a well-formed BCP 47 language tag.
+ *
  * @returns {Array<Intl.Locale>} The locales that wrapped from header, if you use `accept-language` header and `*` (any language) or empty string is detected, return an empty array.
  */
 export function getHeaderLocales(
@@ -126,6 +128,31 @@ export function getHeaderLocales(
   })
 }
 
+/**
+ * try to get locales from header
+ *
+ * @description wrap language tags with {@link Intl.Locale | locale}, languages tags will be parsed from `accept-language` header as default. Unlike {@link getHeaderLocales}, this function does not throw an error if the locale cannot be obtained, this function returns `null`.
+ *
+ * @param {Request} request The {@link Request | request}
+ * @param {HeaderOptions['name']} options.name The header name, which is as default `accept-language`.
+ * @param {HeaderOptions['parser']} options.parser The parser function, which is as default {@link parseDefaultHeader}. If you are specifying more than one in your own format, you need a parser.
+ *
+ * @returns {Array<Intl.Locale> | null} The locales that wrapped from header, if you use `accept-language` header and `*` (any language) or empty string is detected, return an empty array. if header are not a well-formed BCP 47 language tag, return `null`.
+ */
+export function tryHeaderLocales(
+  request: Request,
+  {
+    name = ACCEPT_LANGUAGE_HEADER,
+    parser = parseDefaultHeader,
+  }: HeaderOptions = {},
+): Intl.Locale[] | null {
+  try {
+    return getHeaderLocales(request, { name, parser })
+  } catch {
+    return null
+  }
+}
+
 /**
  * get locale from header
  *
@@ -165,6 +192,33 @@ export function getHeaderLocale(
   return getLocaleWithGetter(() => getHeaderLanguages(request, { name, parser })[0] || lang)
 }
 
+/**
+ * try to get locale from header
+ *
+ * @description wrap language tag with {@link Intl.Locale | locale}, languages tags will be parsed from `accept-language` header as default. Unlike {@link getHeaderLocale}, this function does not throw an error if the locale cannot be obtained, this function returns `null`.
+ *
+ * @param {Request} request The {@link Request | request}
+ * @param {string} options.lang The default language tag, Optional. default value is `en-US`. You must specify the language tag with the {@link https://datatracker.ietf.org/doc/html/rfc4646#section-2.1 | BCP 47 syntax}.
+ * @param {HeaderOptions['name']} options.name The header name, which is as default `accept-language`.
+ * @param {HeaderOptions['parser']} options.parser The parser function, which is as default {@link parseDefaultHeader}. If you are specifying more than one in your own format, you need a parser.
+ *
+ * @returns {Intl.Locale | null} The first locale that resolved from header string. if you use `accept-language` header and `*` (any language) or empty string is detected, return `en-US`. if `lang` option or header are not a well-formed BCP 47 language tag, return `null`.
+ */
+export function tryHeaderLocale(
+  request: Request,
+  {
+    lang = DEFAULT_LANG_TAG,
+    name = ACCEPT_LANGUAGE_HEADER,
+    parser = parseDefaultHeader,
+  }: HeaderOptions & { lang?: string } = {},
+): Intl.Locale | null {
+  try {
+    return getHeaderLocale(request, { lang, name, parser })
+  } catch {
+    return null
+  }
+}
+
 /**
  * get locale from cookie
  *
@@ -203,6 +257,28 @@ export function getCookieLocale(
   return getLocaleWithGetter(getter)
 }
 
+/**
+ * try to get locale from cookie
+ *
+ * @description Unlike {@link getCookieLocale}, this function does not throw an error if the locale cannot be obtained, this function returns `null`.
+ *
+ * @param {Request} request The {@link Request | request}
+ * @param {string} options.lang The default language tag, default is `en-US`. You must specify the language tag with the {@link https://datatracker.ietf.org/doc/html/rfc4646#section-2.1 | BCP 47 syntax}.
+ * @param {string} options.name The cookie name, default is `i18n_locale`
+ *
+ * @returns {Intl.Locale | null} The locale that resolved from cookie. if `lang` option or cookie name value are not a well-formed BCP 47 language tag, return `null`.
+ */
+export function tryCookieLocale(
+  request: Request,
+  { lang = DEFAULT_LANG_TAG, name = DEFAULT_COOKIE_NAME } = {},
+): Intl.Locale | null {
+  try {
+    return getCookieLocale(request, { lang, name })
+  } catch {
+    return null
+  }
+}
+
 /**
  * set locale to the response `Set-Cookie` header.
  *
@@ -264,6 +340,28 @@ export function getPathLocale(
   return _getPathLocale(new URL(request.url), { lang, parser })
 }
 
+/**
+ * try to get the locale from the path
+ *
+ * @description Unlike {@link getPathLocale}, this function does not throw an error if the locale cannot be obtained, this function returns `null`.
+ *
+ * @param {Request} request the {@link Request | request}
+ * @param {PathOptions['lang']} options.lang the language tag, which is as default `'en-US'`. optional
+ * @param {PathOptions['parser']} options.parser the path language parser, default {@link pathLanguageParser}, optional
+ *
+ * @returns {Intl.Locale | null} The locale that resolved from path. if the language in the path, that is not a well-formed BCP 47 language tag, return `null`.
+ */
+export function tryPathLocale(
+  request: Request,
+  { lang = DEFAULT_LANG_TAG, parser = pathLanguageParser }: PathOptions = {},
+): Intl.Locale | null {
+  try {
+    return getPathLocale(request, { lang, parser })
+  } catch {
+    return null
+  }
+}
+
 /**
  * get the locale from the query
  *
@@ -282,6 +380,28 @@ export function getQueryLocale(
   return _getQueryLocale(new URL(request.url), { lang, name })
 }
 
+/**
+ * try to get the locale from the query
+ *
+ * @description Unlike {@link getQueryLocale}, this function does not throw an error if the locale cannot be obtained, this function returns `null`.
+ *
+ * @param {Request} request the {@link Request | request}
+ * @param {QueryOptions['lang']} options.lang the language tag, which is as default `'en-US'`. optional
+ * @param {QueryOptions['name']} options.name the query param name, default `'locale'`. optional
+ *
+ * @returns {Intl.Locale | null} The locale that resolved from query. if the language in the query, that is not a well-formed BCP 47 language tag, return `null`.
+ */
+export function tryQueryLocale(
+  request: Request,
+  { lang = DEFAULT_LANG_TAG, name = 'locale' }: QueryOptions = {},
+): Intl.Locale | null {
+  try {
+    return getQueryLocale(request, { lang, name })
+  } catch {
+    return null
+  }
+}
+
 /**
  * get navigator languages
  *

src/h3.test.ts

@@ -10,6 +10,11 @@ import {
   getPathLocale,
   getQueryLocale,
   setCookieLocale,
+  tryCookieLocale,
+  tryHeaderLocale,
+  tryHeaderLocales,
+  tryPathLocale,
+  tryQueryLocale,
 } from './h3.ts'
 import { parseAcceptLanguage } from './shared.ts'
 import { DEFAULT_COOKIE_NAME, DEFAULT_LANG_TAG } from './constants.ts'
@@ -219,6 +224,37 @@ describe('getHeaderLocales', () => {
   })
 })
 
+describe('tryHeaderLocales', () => {
+  test('success', () => {
+    const mockEvent = {
+      node: {
+        req: {
+          method: 'GET',
+          headers: {
+            'accept-language': 'en-US,en;q=0.9,ja;q=0.8',
+          },
+        },
+      },
+    } as H3Event
+    expect(tryHeaderLocales(mockEvent)!.map((locale) => locale.baseName))
+      .toEqual(['en-US', 'en', 'ja'])
+  })
+
+  test('failed', () => {
+    const mockEvent = {
+      node: {
+        req: {
+          method: 'GET',
+          headers: {
+            'accept-language': 'hoge',
+          },
+        },
+      },
+    } as H3Event
+    expect(tryHeaderLocales(mockEvent)).toBeNull()
+  })
+})
+
 describe('getHeaderLocale', () => {
   test('basic', () => {
     const mockEvent = {
@@ -308,6 +344,41 @@ describe('getHeaderLocale', () => {
   })
 })
 
+describe('tryHeaderLocale', () => {
+  test('success', () => {
+    const mockEvent = {
+      node: {
+        req: {
+          method: 'GET',
+          headers: {
+            'accept-language': 'en-US,en;q=0.9,ja;q=0.8',
+          },
+        },
+      },
+    } as H3Event
+    const locale = tryHeaderLocale(mockEvent)!
+
+    expect(locale.baseName).toEqual('en-US')
+    expect(locale.language).toEqual('en')
+    expect(locale.region).toEqual('US')
+  })
+
+  test('failed', () => {
+    const mockEvent = {
+      node: {
+        req: {
+          method: 'GET',
+          headers: {
+            'accept-language': 's',
+          },
+        },
+      },
+    } as H3Event
+
+    expect(tryHeaderLocale(mockEvent)).toBeNull()
+  })
+})
+
 describe('getCookieLocale', () => {
   test('basic', () => {
     const mockEvent = {
@@ -388,6 +459,41 @@ describe('getCookieLocale', () => {
   })
 })
 
+describe('tryCookieLocale', () => {
+  test('success', () => {
+    const mockEvent = {
+      node: {
+        req: {
+          method: 'GET',
+          headers: {
+            cookie: `${DEFAULT_COOKIE_NAME}=en-US`,
+          },
+        },
+      },
+    } as H3Event
+    const locale = tryCookieLocale(mockEvent)!
+
+    expect(locale.baseName).toEqual('en-US')
+    expect(locale.language).toEqual('en')
+    expect(locale.region).toEqual('US')
+  })
+
+  test('failed', () => {
+    const mockEvent = {
+      node: {
+        req: {
+          method: 'GET',
+          headers: {
+            cookie: 'intlify_locale=f',
+          },
+        },
+      },
+    } as H3Event
+
+    expect(tryCookieLocale(mockEvent, { name: 'intlify_locale' })).toBeNull()
+  })
+})
+
 describe('setCookieLocale', () => {
   let app: App
   let request: SuperTest<Test>
@@ -469,6 +575,36 @@ test('getPathLocale', async () => {
   expect(res.body).toEqual({ locale: 'en' })
 })
 
+describe('tryPathLocale', () => {
+  test('success', async () => {
+    const app = createApp({ debug: false })
+    const request = supertest(toNodeListener(app))
+
+    app.use(
+      '/',
+      eventHandler((event) => {
+        return { locale: tryPathLocale(event)!.toString() }
+      }),
+    )
+    const res = await request.get('/en/foo')
+    expect(res.body).toEqual({ locale: 'en' })
+  })
+
+  test('failed', async () => {
+    const app = createApp({ debug: false })
+    const request = supertest(toNodeListener(app))
+
+    app.use(
+      '/',
+      eventHandler((event) => {
+        return { locale: tryPathLocale(event) }
+      }),
+    )
+    const res = await request.get('/s/foo')
+    expect(res.body).toEqual({ locale: null })
+  })
+})
+
 test('getQueryLocale', async () => {
   const app = createApp({ debug: false })
   const request = supertest(toNodeListener(app))
@@ -482,3 +618,33 @@ test('getQueryLocale', async () => {
   const res = await request.get('/?locale=ja')
   expect(res.body).toEqual({ locale: 'ja' })
 })
+
+describe('tryQueryLocale', () => {
+  test('success', async () => {
+    const app = createApp({ debug: false })
+    const request = supertest(toNodeListener(app))
+
+    app.use(
+      '/',
+      eventHandler((event) => {
+        return { locale: tryQueryLocale(event)!.toString() }
+      }),
+    )
+    const res = await request.get('/?locale=ja')
+    expect(res.body).toEqual({ locale: 'ja' })
+  })
+
+  test('failed', async () => {
+    const app = createApp({ debug: false })
+    const request = supertest(toNodeListener(app))
+
+    app.use(
+      '/',
+      eventHandler((event) => {
+        return { locale: tryQueryLocale(event) }
+      }),
+    )
+    const res = await request.get('/?locale=j')
+    expect(res.body).toEqual({ locale: null })
+  })
+})