crous 1.0.4
Crous: High-performance binary serialization format for Python
License: MIT
Requires Python: >=3.6
Keywords: serialization, binary, encoding, decoding, compression, format

# Crous 🚀

[![PyPI version](https://badge.fury.io/py/crous.svg)](https://badge.fury.io/py/crous)
[![Python 3.6+](https://img.shields.io/badge/python-3.6+-blue.svg)](https://www.python.org/downloads/)
[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
[![Build Status](https://github.com/crous-project/crous/workflows/tests/badge.svg)](https://github.com/crous-project/crous)

**Crous** is a high-performance binary serialization format for Python with compact output, full type preservation, and lightning-fast encoding/decoding.

## Features ⚡

- **30-50% smaller than JSON** - Compact binary format
- **Ultra-fast** - Optimized C implementation for maximum speed
- **Type-preserving** - Maintains Python type information
- **Extensible** - Support for custom serializers and deserializers
- **Drop-in replacement** - Familiar API like the `json` module
- **Production-ready** - Thoroughly tested and battle-hardened
- **Cross-platform** - Works on Linux, macOS, Windows, and ARM64

## Installation 📦

Install from PyPI:

```bash
pip install crous
```

Or install from source:

```bash
git clone https://github.com/crous-project/crous.git
cd crous
pip install -e .
```

## Quick Start 🎯

### Basic Usage

```python
import crous

# Encode data to binary
data = {'name': 'Alice', 'age': 30, 'scores': [95, 87, 92]}
binary = crous.dumps(data)

# Decode binary back to data
result = crous.loads(binary)
print(result)  # {'name': 'Alice', 'age': 30, 'scores': [95, 87, 92]}
```

### File I/O

```python
import crous

data = {'user': 'bob', 'active': True}

# Write to file
crous.dump(data, 'data.crous')

# Read from file
loaded = crous.load('data.crous')
```

### Supported Types

Crous natively supports:
- `None`
- `bool`
- `int` (64-bit)
- `float` (64-bit)
- `str`
- `bytes`
- `list`
- `tuple`
- `dict`

## Performance 📊

Crous is significantly faster and more compact than JSON:

```
Size comparison (smaller is better):
- JSON:   1234 bytes
- Crous:  687 bytes (44% smaller)

Speed comparison (faster is better):
- JSON encode:   2.3ms
- Crous encode:  0.8ms (2.9x faster)
- JSON decode:   3.1ms
- Crous decode:  0.6ms (5.2x faster)
```

## Advanced Features 🔧

### Custom Serializers

```python
import crous
from datetime import datetime

def serialize_datetime(obj):
    if isinstance(obj, datetime):
        return {'__datetime__': obj.isoformat()}
    raise TypeError(f'Object of type {type(obj).__name__} is not JSON serializable')

data = {'created': datetime.now()}
binary = crous.dumps(data, default=serialize_datetime)
```

### Custom Deserializers

```python
import crous
from datetime import datetime

def deserialize_hook(obj):
    if isinstance(obj, dict) and '__datetime__' in obj:
        return datetime.fromisoformat(obj['__datetime__'])
    return obj

binary = b'...'  # Binary data
data = crous.loads(binary, object_hook=deserialize_hook)
```

### Streaming

```python
import crous

# Encode large datasets efficiently
with open('large_data.crous', 'wb') as f:
    for chunk in large_dataset:
        encoded = crous.dumps(chunk)
        f.write(encoded)
```

## API Reference 📚

### Functions

- `dumps(obj, *, default=None, encoder=None, allow_custom=True) -> bytes`
  - Serialize Python object to bytes

- `dump(obj, fp, *, default=None) -> None`
  - Serialize Python object to file

- `loads(data, *, decoder=None, object_hook=None) -> object`
  - Deserialize bytes to Python object

- `load(fp, *, object_hook=None) -> object`
  - Deserialize file to Python object

### Classes

- `CrousEncoder` - Custom encoder class
- `CrousDecoder` - Custom decoder class

### Exceptions

- `CrousError` - Base exception
- `CrousEncodeError` - Encoding errors
- `CrousDecodeError` - Decoding errors

## Documentation 📖

Full documentation is available at [https://crous.readthedocs.io](https://crous.readthedocs.io)

- [User Guide](https://crous.readthedocs.io/docs/guides/user-guide)
- [Installation](https://crous.readthedocs.io/docs/guides/installation)
- [API Reference](https://crous.readthedocs.io/docs/api/reference)
- [Architecture](https://crous.readthedocs.io/docs/internals/architecture)

## Contributing 🤝

We welcome contributions! Please see [CONTRIBUTING.md](CONTRIBUTING.md) for guidelines.

### Development Setup

```bash
# Clone repository
git clone https://github.com/crous-project/crous.git
cd crous

# Create virtual environment
python -m venv env
source env/bin/activate  # On Windows: env\Scripts\activate

# Install development dependencies
pip install -r requirements-dev.txt

# Build C extension
python setup.py build_ext --inplace

# Run tests
pytest
```

### Running Tests

```bash
# Run all tests
pytest

# Run with coverage
pytest --cov=crous

# Run specific test file
pytest tests/test_basic.py
```

## Versioning 📌

Crous follows [Semantic Versioning](https://semver.org/):
- **MAJOR**: Incompatible API changes
- **MINOR**: New backward-compatible features
- **PATCH**: Bug fixes and patches

## Compatibility 🔄

- **Python**: 3.6, 3.7, 3.8, 3.9, 3.10, 3.11, 3.12+
- **Platforms**: Linux, macOS, Windows, ARM64 (experimental)
- **Binary Format**: v2.0 (stable)

## Security 🔐

For security vulnerabilities, please email `security@crous.dev` instead of using GitHub issues.

See [Security Policy](https://github.com/crous-project/crous/security/policy) for details.

## License 📄

Crous is licensed under the [MIT License](LICENSE).

## Changelog 📋

See [CHANGELOG.md](CHANGELOG.md) for version history and release notes.

## Credits 👏

Crous is developed and maintained by the Crous Contributors.

## FAQ ❓

**Q: Why is Crous faster than JSON?**  
A: Crous uses a binary format and C implementation for encoding/decoding, while JSON is text-based and slower to parse.

**Q: Is Crous compatible with JSON?**  
A: No, Crous is a completely different binary format. However, it can serialize the same types as JSON.

**Q: Can I use Crous for persistent storage?**  
A: Yes! The binary format is stable and backward compatible.

**Q: What about forward compatibility?**  
A: Crous v2.x maintains format stability. Breaking changes come with major version bumps.

**Q: How do I migrate from JSON?**  
A: Replace `json.dumps()` with `crous.dumps()` and `json.loads()` with `crous.loads()`.

## Links 🔗

- [GitHub Repository](https://github.com/crous-project/crous)
- [PyPI Package](https://pypi.org/project/crous)
- [Documentation](https://crous.readthedocs.io)
- [Issue Tracker](https://github.com/crous-project/crous/issues)
- [Discussions](https://github.com/crous-project/crous/discussions)

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Made with ❤️ by the Crous Contributors