Google Translate Dart Package

This Dart package provides a simple interface to interact with the Google Translate API. It allows you to translate text between different languages, detect the language of a given text, and retrieve a list of supported languages.

Features

• Translate text: Translate a given text from one language to another.
• Detect language: Automatically detect the language of the input text.
• Supported languages: Fetch a list of languages supported by Google Translate.

Installation

1. Add the following dependency to your pubspec.yaml file:

   dependencies:
     google_translate:
       git:
         url: https://github.com/your-repository/google_translate.git
   

2. Run flutter pub get to install the dependencies.

Usage

1. Import the package

import 'package:google_translate/google_translate.dart';

2. Initialize the GoogleTranslate instance

You need a Google Cloud API key to use the Google Translate API. You can create one here.

void main() {
  final googleTranslate = GoogleTranslate('YOUR_GOOGLE_API_KEY');
}

3. Translate text

You can translate text between different languages using the translate method. If the source language is unknown, the method will automatically detect the language.

void main() async {
  final googleTranslate = GoogleTranslate('YOUR_GOOGLE_API_KEY');

  // Translate from Spanish to English
  final translatedText = await googleTranslate.translate(
    text: 'Hola',
    targetLang: 'en',
  );
  print(translatedText); // Output: Hello
}

You can also specify the source language explicitly:

final translatedText = await googleTranslate.translate(
  text: 'Bonjour',
  sourceLang: 'fr',  // Specify the source language
  targetLang: 'en',
);
print(translatedText);  // Output: Hello

4. Detect the language of a text

You can detect the language of a given text using the detectLanguage method.

void main() async {
  final googleTranslate = GoogleTranslate('YOUR_GOOGLE_API_KEY');

  // Detect the language of the text
  final detectedLanguage = await googleTranslate.detectLanguage('Hola');
  print(detectedLanguage); // Output: es (Spanish)
}

5. Get the list of supported languages

You can retrieve the list of languages supported by Google Translate:

void main() async {
  final googleTranslate = GoogleTranslate('YOUR_GOOGLE_API_KEY');

  // Get the supported languages
  final languages = await googleTranslate.getSupportedLanguages();
  print(languages);  // Output: [en, es, fr, de, ...]
}

Running Tests

To run the tests for this package, you can use the following command:

flutter test

The tests are written using the test and mockito packages to mock API responses.

Example Test Case

test('should return translated text when source language is provided', () async {
  // Arrange: mock the API response
  final mockClient = MockClient();
  final googleTranslate = GoogleTranslate('FAKE_API_KEY');
  
  final response = jsonEncode({
    'data': {
      'translations': [
        {'translatedText': 'Hello'}
      ]
    }
  });
  
  when(mockClient.post(any, headers: anyNamed('headers')))
      .thenAnswer((_) async => http.Response(response, 200));

  // Act: call the translate function
  final translatedText = await googleTranslate.translate(
    text: 'Hola',
    sourceLang: 'es',
    targetLang: 'en',
  );

  // Assert: verify the result
  expect(translatedText, equals('Hello'));
});

API Key Setup

To use this package, you need to enable the Google Cloud Translation API and generate an API key. Follow these steps:

1. Go to the Google Cloud Console.
2. Select or create a new project.
3. Navigate to API & Services > Library.
4. Search for "Cloud Translation API" and enable it.
5. Navigate to Credentials and create a new API key.
6. Use the API key in your application.

Contributing

Contributions are welcome! Feel free to submit a pull request or file an issue if you encounter any problems or have suggestions for improvements.

License

This package is licensed under the MIT License. See the LICENSE file for more information.