Flutter AI i18n Extractor

An intelligent Flutter package that automatically extracts hardcoded strings from your Flutter project and generates professional translations using AI, with full compatibility with flutter_intl and intl_utils workflows.

Features

  • Professional Translation: Leverage AI models and translation services for high-quality translations
  • Multiple Translation Options: Choose from free translation services or premium AI models
  • Compatibility with flutter_intl: Seamlessly integrates with existing flutter_intl projects
  • Smart Key Generation: Automatically generates meaningful keys for your translations
  • Batch Processing: Extract and translate multiple strings efficiently
  • Customizable: Configure translation providers, target languages, and extraction patterns
  • CLI Support: Easy-to-use command-line interface

Translation Providers

Translation Module Support FREE
Google Translate ✅ ✅ FREE
Google Translate 2 ✅ ✅ FREE
Microsoft Bing Translate ✅ ✅ FREE
Libre Translate ✅ ✅ FREE
Argos Translate ✅ ✅ FREE
DeepL Translate ✅ require API KEY (DEEPL_API_KEY as env)
optional API URL (DEEPL_API_URL as env)
gpt-4o ✅ require API KEY (OPENAI_API_KEY as env)
gpt-3.5-turbo ✅ require API KEY (OPENAI_API_KEY as env)
gpt-4 ✅ require API KEY (OPENAI_API_KEY as env)
gpt-4o-mini ✅ require API KEY (OPENAI_API_KEY as env)
Claude 3.5 Sonnet ✅ require API KEY (ANTHROPIC_API_KEY as env)
Gemini Pro ✅ require API KEY (GOOGLE_AI_API_KEY as env)
DeepSeek ✅ require API KEY (DEEPSEEK_API_KEY as env)
Groq ✅ require API KEY (GROQ_API_KEY as env)
Cohere ✅ require API KEY (COHERE_API_KEY as env)
Hugging Face ✅ require API KEY (HUGGINGFACE_API_KEY as env)
Ollama ✅ require local installation

Compatibility with flutter_intl

Yes, this package is fully compatible with flutter_intl and intl_utils workflows!

If you already have flutter_intl configured in your pubspec.yaml:

# Configuration for intl_utils
flutter_intl:
  enabled: true
  class_name: S
  main_locale: en
  arb_dir: lib/l10n
  output_dir: lib/generated
  localizely:
    project_id: # Add your Localizely project ID if using it

The extractor will:

  • Detect your existing configuration automatically
  • Use your configured class_name (e.g., S)
  • Generate ARB files in your specified arb_dir
  • Generate code that works with your existing setup: final l10n = S.of(context);

Installation

Add this package to your pubspec.yaml:

dev_dependencies:
  flutter_ai_i18n_extractor: ^1.0.0

Then run:

flutter pub get

Quick Start

1. Initialize Configuration

flutter packages pub run flutter_ai_i18n_extractor:flutter_ai_i18n_extractor init

This creates a flutter_ai_i18n_extractor.yaml configuration file:

flutter_ai_i18n_extractor:
  # L10n Settings (auto-detected from flutter_intl if present)
  arb_dir: lib/l10n
  template_arb_file: app_en.arb
  output_class: AppLocalizations  # or 'S' if using flutter_intl
  
  # AI Configuration
  ai_provider: google_translate # Default: google_translate (free). Choose from:
  # Free Translation Services: google_translate, google_translate_2, bing_translate, libre_translate, argos_translate
  # Translation with API Key: deepl_translate
  # AI Models with API Key: openai, google, anthropic, deepseek, groq, cohere, huggingface, ollama
  api_key: ${OPENAI_API_KEY}  # Use environment variables
  model: gpt-4
  
  # Target Languages
  languages:
    - en
    - es
    - fr
    - de
  
  # Extraction Settings
  scan_paths:
    - lib/
  exclude_patterns:
    - lib/generated/
    - "**/*.g.dart"
    - "**/*.freezed.dart"
  
  # Key Generation
  key_naming_convention: camelCase  # or snake_case
  max_key_length: 35
  context_aware_naming: true
  
  # Processing Options
  dry_run: false
  backup_files: true
  preserve_comments: true

2. Set Up API Key

Set up your API keys as environment variables (only required for paid services):

# Free Translation Services (No API Key Required)
# - google_translate
# - google_translate_2  
# - bing_translate
# - libre_translate
# - argos_translate

# Translation Services (API Key Required)
# For DeepL Translate
export DEEPL_API_KEY="your-deepl-api-key"
export DEEPL_API_URL="https://api-free.deepl.com"  # Optional, defaults to free tier

# AI Models (API Key Required)
# For OpenAI
export OPENAI_API_KEY="your-api-key-here"

# For Google AI
export GOOGLE_AI_API_KEY="your-api-key-here"

# For Anthropic
export ANTHROPIC_API_KEY="your-api-key-here"

# For DeepSeek (Free tier available)
export DEEPSEEK_API_KEY="your-api-key-here"

# For Groq (Free tier available)
export GROQ_API_KEY="your-api-key-here"

# For Cohere (Free tier available)
export COHERE_API_KEY="your-api-key-here"

# For Hugging Face (Free tier available)
export HUGGINGFACE_API_KEY="your-api-key-here"

# For Ollama (Local - no API key needed)
export OLLAMA_BASE_URL="http://localhost:11434"  # Optional, defaults to localhost

# Optional: Custom URLs for self-hosted services
export LIBRETRANSLATE_URL="https://libretranslate.de"  # Default LibreTranslate instance
export ARGOS_TRANSLATE_URL="http://localhost:5000"     # Local Argos Translate instance

3. Extract and Translate

# Extract strings and generate translations
flutter packages pub run flutter_ai_i18n_extractor:flutter_ai_i18n_extractor extract

# Preview extracted strings and select which ones to process
flutter packages pub run flutter_ai_i18n_extractor:flutter_ai_i18n_extractor extract --preview

# Or run in dry-run mode first to see what would be extracted
flutter packages pub run flutter_ai_i18n_extractor:flutter_ai_i18n_extractor extract --dry-run

Usage Examples

Before Extraction

class LoginPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Login'),
      ),
      body: Column(
        children: [
          TextField(
            decoration: InputDecoration(
              hintText: 'Enter your email',
              labelText: 'Email',
            ),
          ),
          TextField(
            decoration: InputDecoration(
              hintText: 'Enter your password',
              labelText: 'Password',
            ),
            obscureText: true,
          ),
          ElevatedButton(
            onPressed: () {},
            child: Text('Sign In'),
          ),
        ],
      ),
    );
  }
}

After Extraction (flutter_intl compatible)

class LoginPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final l10n = S.of(context);  // Uses your configured class_name
    
    return Scaffold(
      appBar: AppBar(
        title: Text(l10n.loginPageTitle),
      ),
      body: Column(
        children: [
          TextField(
            decoration: InputDecoration(
              hintText: l10n.emailFieldHint,
              labelText: l10n.emailFieldLabel,
            ),
          ),
          TextField(
            decoration: InputDecoration(
              hintText: l10n.passwordFieldHint,
              labelText: l10n.passwordFieldLabel,
            ),
            obscureText: true,
          ),
          ElevatedButton(
            onPressed: () {},
            child: Text(l10n.signInButtonText),
          ),
        ],
      ),
    );
  }
}

Generated ARB Files

lib/l10n/app_en.arb:

{
  "@@locale": "en",
  "loginPageTitle": "Login",
  "@loginPageTitle": {
    "description": "Title for the login page"
  },
  "emailFieldHint": "Enter your email",
  "@emailFieldHint": {
    "description": "Hint text for email input field"
  },
  "emailFieldLabel": "Email",
  "@emailFieldLabel": {
    "description": "Label for email input field"
  },
  "passwordFieldHint": "Enter your password",
  "@passwordFieldHint": {
    "description": "Hint text for password input field"
  },
  "passwordFieldLabel": "Password",
  "@passwordFieldLabel": {
    "description": "Label for password input field"
  },
  "signInButtonText": "Sign In",
  "@signInButtonText": {
    "description": "Text for sign in button"
  }
}

lib/l10n/app_es.arb:

{
  "@@locale": "es",
  "loginPageTitle": "Iniciar Sesión",
  "emailFieldHint": "Ingresa tu correo electrónico",
  "emailFieldLabel": "Correo Electrónico",
  "passwordFieldHint": "Ingresa tu contraseña",
  "passwordFieldLabel": "Contraseña",
  "signInButtonText": "Iniciar Sesión"
}

CLI Commands

Initialize

flutter packages pub run flutter_ai_i18n_extractor:flutter_ai_i18n_extractor init

Creates a configuration file with sensible defaults.

Extract

flutter packages pub run flutter_ai_i18n_extractor:flutter_ai_i18n_extractor extract [options]

Options:

  • --preview, -p: Show extracted strings and allow selection before processing
  • --dry-run: Preview changes without modifying files
  • --config: Specify custom config file path
  • --languages: Override target languages (comma-separated)

Update

flutter packages pub run flutter_ai_i18n_extractor:flutter_ai_i18n_extractor update

Updates existing translations with new strings.

Validate

flutter packages pub run flutter_ai_i18n_extractor:flutter_ai_i18n_extractor validate

Validates ARB files and checks for missing translations.

Stats

flutter packages pub run flutter_ai_i18n_extractor:flutter_ai_i18n_extractor stats

Shows statistics about your localization coverage.

Configuration Options

Translation Providers

Free Translation Services (No API Key Required)

Google Translate (Default)
ai_provider: google_translate
# No API key required - completely free
Google Translate 2 (Alternative Endpoint)
ai_provider: google_translate_2
# No API key required - completely free
Microsoft Bing Translate
ai_provider: bing_translate
# No API key required - completely free
LibreTranslate
ai_provider: libre_translate
# No API key required - uses public instance
# Optional: Set LIBRETRANSLATE_URL for custom instance
Argos Translate
ai_provider: argos_translate
# No API key required - requires local installation
# Optional: Set ARGOS_TRANSLATE_URL for custom instance

Translation Services (API Key Required)

DeepL Translate
ai_provider: deepl_translate
api_key: ${DEEPL_API_KEY}
# Optional: Set DEEPL_API_URL for custom endpoint

AI Models (API Key Required)

OpenAI
ai_provider: openai
api_key: ${OPENAI_API_KEY}
model: gpt-4o  # or gpt-4, gpt-3.5-turbo, gpt-4o-mini
Google AI
ai_provider: google
api_key: ${GOOGLE_AI_API_KEY}
model: gemini-1.5-pro  # or gemini-1.5-flash
Anthropic
ai_provider: anthropic
api_key: ${ANTHROPIC_API_KEY}
model: claude-3-5-sonnet-20241022  # or claude-3-haiku-20240307
DeepSeek
ai_provider: deepseek
api_key: ${DEEPSEEK_API_KEY}
model: deepseek-chat  # or deepseek-coder
Groq
ai_provider: groq
api_key: ${GROQ_API_KEY}
model: llama-3.1-70b-versatile  # or mixtral-8x7b-32768
Cohere
ai_provider: cohere
api_key: ${COHERE_API_KEY}
model: command-r-plus  # or command-r
Hugging Face
ai_provider: huggingface
api_key: ${HUGGINGFACE_API_KEY}
model: microsoft/DialoGPT-large  # or any compatible model
Ollama
ai_provider: ollama
model: llama3.1  # or any locally installed model

Note: Ollama requires local installation. Download models using ollama pull <model-name>.

Key Naming Conventions

camelCase (default)

key_naming_convention: camelCase

Generates keys like: loginPageTitle, emailFieldHint

snake_case

key_naming_convention: snake_case

Generates keys like: login_page_title, email_field_hint

Exclusion Patterns

exclude_patterns:
  - lib/generated/
  - "**/*.g.dart"
  - "**/*.freezed.dart"
  - "**/test/**"
  - "lib/l10n/"

Integration with Existing Projects

flutter_intl Integration

If you're already using flutter_intl, the extractor will:

  1. Auto-detect your configuration from pubspec.yaml
  2. Use your existing class name (e.g., S instead of AppLocalizations)
  3. Generate compatible ARB files in your configured directory
  4. Preserve your existing translations when updating

Manual Integration

For projects without flutter_intl, add to your pubspec.yaml:

dependencies:
  flutter:
    sdk: flutter
  flutter_localizations:
    sdk: flutter
  intl: any

flutter:
  generate: true

Create l10n.yaml:

arb-dir: lib/l10n
template-arb-file: app_en.arb
output-localization-file: app_localizations.dart
output-class: AppLocalizations

Best Practices

1. Use Dry Run First

flutter packages pub run flutter_ai_i18n_extractor:flutter_ai_i18n_extractor extract --dry-run

2. Review Generated Keys

The AI generates meaningful keys, but review them for consistency with your naming conventions.

3. Backup Your Files

The tool creates backups by default, but consider using version control.

4. Incremental Updates

Use the update command to add new strings without affecting existing translations.

5. Context-Aware Naming

Enable context_aware_naming for better key generation based on UI context.

Troubleshooting

Common Issues

API Key Not Found

Error: AI API key is not properly configured

Solution: Set the environment variable for your AI provider.

No Strings Found

Warning: No extractable strings found

Solution: Check your scan_paths and exclude_patterns configuration.

Compilation Errors After Extraction

Error: The getter 'someKey' isn't defined

Solution: Run flutter packages pub run build_runner build to generate localization files.

Debug Mode

Run with verbose output:

flutter packages pub run flutter_ai_i18n_extractor:flutter_ai_i18n_extractor extract --verbose

Contributing

Contributions are welcome! Please read our Contributing Guide for details.

License

This project is licensed under the MIT License - see the LICENSE file for details.

Support

If you encounter any issues or have questions:

  1. Check the troubleshooting section
  2. Search existing issues
  3. Create a new issue with detailed information

Roadmap

  • Support for more AI providers
  • Integration with translation services (Google Translate, DeepL)
  • VS Code extension
  • Pluralization support
  • Custom translation templates
  • Translation quality scoring

Libraries

flutter_ai_i18n_extractor
Flutter AI i18n Extractor