Model From JSON 🚀

A zero-setup Dart CLI tool that generates clean, Equatable-ready Dart model classes directly from JSON.

✅ No annotations
✅ No build_runner
✅ No .g.dart files
✅ Just instant model generation

⚡ Generates models in under 1 second for most API JSON files — no codegen pipeline needed.

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✨ Why Model From JSON?

Most Flutter model generators require:

• Annotations (@JsonSerializable)
• build_runner commands
• Generated .g.dart part files
• Extra boilerplate setup

model_from_json is different:

✅ Works instantly
✅ Outputs plain Dart files immediately
✅ Perfect for rapid development and API prototyping

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🎬 Demo

Generate models instantly:

model_from_json complex.json --name ApiResponse --out lib/models

Output:

✅ Done! Generated 6 model files:

📄 api_response.dart
📄 meta.dart
📄 user.dart
📄 accounts.dart
📄 subscription.dart
📄 features.dart

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✅ Features

• ✅ Generate Dart model classes automatically from JSON

• ✅ Supports nested objects (profile, subscription, etc.)

• ✅ Supports lists of nested objects (accounts, features, etc.)

• ✅ Generates complete boilerplate:

  • fromJson()
  • toJson() (with nested serialization)
  • Equatable props

• ✅ Generates multiple .dart files recursively

• ✅ Supports both:

  • Command mode
  • Interactive mode

• ✅ Optional output folder support (--out)

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📦 Installation

Activate globally:

dart pub global activate model_from_json

Run anywhere:

model_from_json <json_path> --name ClassName

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🚀 Usage

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✅ Command Mode

Generate models into the current directory:

model_from_json complex.json --name ApiResponse

Generate models into a folder:

model_from_json complex.json --name ApiResponse --out lib/models

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✅ Interactive Mode

Run without arguments:

model_from_json

You will be guided step-by-step:

Enter JSON file path: ultra.json
Enter root class name: ApiResponse
Enter output folder [.] : lib/models

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🧾 Example Input

complex.json

{
  "meta": {
    "request_id": "REQ-123",
    "success": true
  },
  "user": {
    "id": 101,
    "name": "Dipesh Panchal",
    "roles": ["trader", "developer"]
  },
  "accounts": [
    {
      "broker": "zerodha",
      "balance": 250000.75
    }
  ],
  "subscription": {
    "plan": "pro",
    "features": [
      {
        "name": "nested_models",
        "enabled": true
      }
    ]
  }
}

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✅ Example Output

api_response.dart

class ApiResponse extends Equatable {
  final Meta meta;
  final User user;
  final List<Accounts> accounts;
  final Subscription subscription;

  const ApiResponse({
    required this.meta,
    required this.user,
    required this.accounts,
    required this.subscription,
  });

  factory ApiResponse.fromJson(Map<String, dynamic> json) {
    return ApiResponse(
      meta: Meta.fromJson(json['meta'] ?? {}),
      user: User.fromJson(json['user'] ?? {}),
      accounts: (json['accounts'] as List? ?? [])
          .map((e) => Accounts.fromJson(e))
          .toList(),
      subscription: Subscription.fromJson(json['subscription'] ?? {}),
    );
  }
}

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📂 Output Structure

Generated folder example:

lib/models/
 ├── api_response.dart
 ├── meta.dart
 ├── user.dart
 ├── accounts.dart
 ├── subscription.dart
 └── features.dart

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⚙️ CLI Options

Option	Description
--name	Root class name (required)
--out	Output folder (optional)
--help	Show CLI usage instructions

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✅ Roadmap

Planned future improvements:

• Nullable type inference (String? phone)
• Dictionary/Map field support (Map<String,dynamic> metadata)
• Smarter naming (daily_pnl → DailyPnl)
• Barrel export generation (models.dart)
• Optional Freezed/json_serializable generation mode

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🤝 Contributing

Pull requests and improvements are welcome!

git clone https://github.com/yourusername/model_from_json.git
cd model_from_json
dart pub get
dart run

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📜 License

MIT License © 2026 Dipesh Panchal

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⭐ Support

If you find this tool useful, consider starring the repo and sharing it with the Flutter community 🚀