add known working language codes as exports

README.md

@@ -105,6 +105,27 @@ Please see [CHANGELOG](https://github.com/zlargon/google-tts/blob/master/CHANGEL
      .catch(console.error);
    ```
 
+### 5. `languages`
+
+- `.get()` returns a list of known language codes that work
+- `findByCode` or `findByName` to search within list
+- Example:
+   ```
+   const googleTTS = require('google-tts-api');
+
+   const list = googleTTS.languages.get();
+   console.log(list) // [{ code: '...', name: '...' }, ...]
+
+   const english = googleTTS.languages.findByCode('en-US');
+   console.log(english) // { code: 'en-US', name: 'English (United States)' }
+
+   const english = googleTTS.languages.findByName('English (United States)');
+   console.log(english) // { code: 'en-US', name: 'English (United States)' }
+
+   // use code to make request
+   const url = googleTTS.getAudioUrl('Hello, world!', { lang: english.code });
+   ```
+
 ## Options (All options are optional)
 
 | Option       | Type      | Default                      | Description                                                                                                                    |

src/assertInputTypes.ts

@@ -1,6 +1,6 @@
-import type { Language } from './types';
+import type { LanguageCode } from './languages';
 
-const assertInputTypes = (text: string, lang: Language, slow: boolean, host: string) => {
+const assertInputTypes = (text: string, lang: LanguageCode, slow: boolean, host: string) => {
   if (typeof text !== 'string' || text.length === 0) {
     throw new TypeError('text should be a string');
   }

src/getAudioBase64.ts

@@ -1,10 +1,10 @@
-import type { Language } from './types';
+import type { LanguageCode } from './languages';
 import assertInputTypes from './assertInputTypes';
 import axios from 'axios';
 import splitLongText from './splitLongText';
 
 interface Option {
-  lang?: Language;
+  lang?: LanguageCode;
   slow?: boolean;
   host?: string;
   timeout?: number;

src/getAudioUrl.ts

@@ -1,10 +1,10 @@
-import type { Language } from './types';
+import type { LanguageCode } from './languages';
 import assertInputTypes from './assertInputTypes';
 import splitLongText from './splitLongText';
 import url from 'url';
 
 interface Option {
-  lang?: Language;
+  lang?: LanguageCode;
   slow?: boolean;
   host?: string;
 }

src/index.ts

@@ -1,4 +1,11 @@
-import { getAudioUrl, getAllAudioUrls } from './getAudioUrl';
-import { getAudioBase64, getAllAudioBase64 } from './getAudioBase64';
+import { getAudioUrl, getAllAudioUrls } from "./getAudioUrl";
+import { getAudioBase64, getAllAudioBase64 } from "./getAudioBase64";
+import languages from "./languages";
 
-export { getAudioUrl, getAllAudioUrls, getAudioBase64, getAllAudioBase64 };
+export {
+  getAudioUrl,
+  getAllAudioUrls,
+  getAudioBase64,
+  getAllAudioBase64,
+  languages,
+};

src/languages.ts

@@ -0,0 +1,90 @@
+export type Language = typeof languages[number];
+export type LanguageCode = typeof languages[number]["code"];
+export type LanguageName = typeof languages[number]["name"];
+
+// prettier-ignore
+const languages = [
+  { code: "af-ZA",       name: "Afrikaans" },
+  { code: "sq",          name: "Albanian" },
+  { code: "ar",          name: "Arabic" },
+  { code: "hy",          name: "Armenian" },
+  { code: "bn-BD",       name: "Bengali (Bangladesh)" },
+  { code: "bn-IN",       name: "Bengali (India)" },
+  { code: "bs",          name: "Bosnian" },
+  { code: "my",          name: "Burmese (Myanmar)" },
+  { code: "ca-ES",       name: "Catalan" },
+  { code: "cmn-Hant-TW", name: "Chinese" },
+  { code: "hr-HR",       name: "Croatian" },
+  { code: "cs-CZ",       name: "Czech" },
+  { code: "da-DK",       name: "Danish" },
+  { code: "nl-NL",       name: "Dutch" },
+  { code: "en-AU",       name: "English (Australia)" },
+  { code: "en-GB",       name: "English (United Kingdom)" },
+  { code: "en-US",       name: "English (United States)" },
+  { code: "eo",          name: "Esperanto" },
+  { code: "et",          name: "Estonian" },
+  { code: "fil-PH",      name: "Filipino" },
+  { code: "fi-FI",       name: "Finnish" },
+  { code: "fr-FR",       name: "French" },
+  { code: "fr-CA",       name: "French (Canada)" },
+  { code: "de-DE",       name: "German" },
+  { code: "el-GR",       name: "Greek" },
+  { code: "gu",          name: "Gujarati" },
+  { code: "hi-IN",       name: "Hindi" },
+  { code: "hu-HU",       name: "Hungarian" },
+  { code: "is-IS",       name: "Icelandic" },
+  { code: "id-ID",       name: "Indonesian" },
+  { code: "it-IT",       name: "Italian" },
+  { code: "ja-JP",       name: "Japanese (Japan)" },
+  { code: "kn",          name: "Kannada" },
+  { code: "km",          name: "Khmer" },
+  { code: "ko-KR",       name: "Korean" },
+  { code: "la",          name: "Latin" },
+  { code: "lv",          name: "Latvian" },
+  { code: "mk",          name: "Macedonian" },
+  { code: "ml",          name: "Malayalam" },
+  { code: "mr",          name: "Marathi" },
+  { code: "ne",          name: "Nepali" },
+  { code: "nb-NO",       name: "Norwegian" },
+  { code: "pl-PL",       name: "Polish" },
+  { code: "pt-BR",       name: "Portuguese" },
+  { code: "ro-RO",       name: "Romanian" },
+  { code: "ru-RU",       name: "Russian" },
+  { code: "sr-RS",       name: "Serbian" },
+  { code: "si",          name: "Sinhala" },
+  { code: "sk-SK",       name: "Slovak" },
+  { code: "es-MX",       name: "Spanish (Mexico)" },
+  { code: "es-ES",       name: "Spanish (Spain)" },
+  { code: "sw",          name: "Swahili" },
+  { code: "sv-SE",       name: "Swedish" },
+  { code: "ta",          name: "Tamil" },
+  { code: "te",          name: "Telugu" },
+  { code: "th-TH",       name: "Thai" },
+  { code: "tr-TR",       name: "Turkish" },
+  { code: "uk-UA",       name: "Ukrainian" },
+  { code: "ur",          name: "Urdu" },
+  { code: "vi-VN",       name: "Vietnamese" },
+  { code: "cy",          name: "Welsh" },
+] as const;
+
+/**
+ * find language from language code
+ *
+ * @param {string} code
+ */
+const findByCode = (code: LanguageCode): Language | undefined =>
+  languages.find((l) => l.code === code);
+
+/**
+ * find language from language name
+ *
+ * @param {string} name
+ */
+const findByName = (name: LanguageName): Language | undefined =>
+  languages.find((l) => l.name === name);
+
+export default {
+  get: () => languages,
+  findByCode,
+  findByName,
+};

test/languages.test.js

@@ -0,0 +1,26 @@
+const googleTTS = require("../dist/index");
+
+test("All voice codes are valid", async (done) => {
+  const responses = googleTTS.languages.get().map((lang) => {
+    return googleTTS
+      .getAudioBase64("test", { lang: lang.code })
+      .catch((err) => {
+        console.log("language code failed: " + lang.code);
+        console.log(err);
+        done.fail("language code failed: " + lang.code);
+      });
+  });
+
+  await Promise.all(responses);
+  done();
+}, 10000);
+
+test("lookup by code", () => {
+  const english = googleTTS.languages.findByCode("en-US");
+  expect(english.name).toBe("English (United States)");
+});
+
+test("lookup by name", () => {
+  const english = googleTTS.languages.findByName("English (United States)");
+  expect(english.code).toBe("en-US");
+});