secureshare-sdk/README.md

Enterprise privacy-preserving data sharing SDK with policy engine, audit logging, and compliance features

# SecureShare SDK

Enterprise privacy-preserving data sharing SDK with policy engine, audit logging, and compliance features.

## Features

- **Policy Engine**: Define and enforce data access policies
- **Privacy Protection**: Tokenization, masking, and encryption
- **Audit Logging**: Comprehensive audit trails for compliance
- **Observer Effect**: Real-time anomaly detection and adaptive responses
- **Multi-tenant Support**: Isolated data and policies per tenant
- **Compliance Ready**: GDPR, HIPAA, CCPA support

## Installation

```bash
npm install secureshare-sdk
```

## Quick Start

```javascript
const { SecureShare, PolicyEvaluator, AuditLogger } = require('secureshare-sdk');

// Create SDK instance
const sdk = new SecureShare({ auditEnabled: true });

// Add a policy
await sdk.addPolicy({
  name: 'PII Protection',
  rules: [{
    condition: "data.type == 'PII'",
    action: 'tokenize',
    constraints: ['user.role == "analyst"']
  }]
});

// Process data
const result = await sdk.processData(
  { name: 'John Doe', email: 'john@example.com', type: 'PII' },
  { user: { role: 'analyst' }, purpose: 'analysis' }
);

console.log(result);
// Output: { name: '***', email: '***', type: 'PII' }
```

## API Reference

### Core Classes

#### `SecureShare`
Main SDK class for data processing and policy management.

```javascript
const sdk = new SecureShare({
  auditEnabled: true  // Enable audit logging
});
```

**Methods:**
- `addPolicy(policy)`: Add a new policy
- `processData(data, context)`: Process data according to policies
- `evaluateData(data, context)`: Evaluate data without processing
- `getAuditLogs(filters)`: Retrieve audit logs

#### `PolicyEvaluator`
Evaluate policies against data and context.

```javascript
const evaluator = new PolicyEvaluator(policy);
const result = evaluator.evaluate(context);
```

#### `AuditLogger`
Log audit events for compliance.

```javascript
AuditLogger.logAuditEvent({
  action: 'data_accessed',
  user: 'user123',
  timestamp: new Date(),
  details: { dataType: 'PII' }
});
```

### Privacy Protection

#### Tokenization
```javascript
const { Tokenizer } = require('secureshare-sdk');
const token = Tokenizer.tokenize('sensitive-data');
const original = Tokenizer.detokenize(token);
```

#### Masking
```javascript
const { Masking } = require('secureshare-sdk');
const masked = Masking.maskValue('john.doe@example.com');
// Output: '***@***.com'
```

#### Encryption
```javascript
const { Encryption } = require('secureshare-sdk');
const encrypted = Encryption.encryptValue('sensitive-data');
const decrypted = Encryption.decryptValue(encrypted);
```

### Policy Types

```javascript
const policy = {
  name: 'Financial Data Policy',
  rules: [{
    condition: "data.type == 'financial'",
    action: 'encrypt',
    constraints: ['user.role == "manager"']
  }]
};
```

**Actions:**
- `allow`: Allow access to data
- `deny`: Deny access to data
- `tokenize`: Replace with tokens
- `mask`: Mask sensitive values
- `encrypt`: Encrypt data
- `log`: Log access without modification

## Examples

### Express.js Middleware
```javascript
const express = require('express');
const { createSecureShareMiddleware } = require('secureshare-sdk');

const app = express();
const sdk = new SecureShare();

app.use('/api/data', createSecureShareMiddleware({
  secureShare: sdk,
  policyContext: (req) => ({
    user: req.user,
    purpose: req.query.purpose
  })
}));
```

### Observer Effect Demo
```javascript
const { ObserverEffectEngine } = require('secureshare-sdk');

const observer = new ObserverEffectEngine(db);
const result = await observer.evaluateObserverEffect({
  userId: 'user123',
  userRole: 'analyst',
  dataType: 'PII',
  accessPattern: 'bulk_export'
});
```

## Configuration

### Environment Variables
```bash
SECURESHARE_AUDIT_LOG=./audit.log
SECURESHARE_JWT_SECRET=your-secret-key
SECURESHARE_DB_URL=postgresql://user:pass@localhost/db
```

### Database Support
- PostgreSQL
- Redis
- MongoDB

## Compliance

The SDK supports various compliance frameworks:

- **GDPR**: Data protection and privacy
- **HIPAA**: Healthcare data protection
- **CCPA**: California consumer privacy
- **SOC 2**: Security controls

## Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests
5. Submit a pull request

## License

MIT License - see LICENSE file for details.

## Support

- Documentation: [GitHub Wiki](https://github.com/your-org/secureshare-sdk/wiki)
- Issues: [GitHub Issues](https://github.com/your-org/secureshare-sdk/issues)
- Discussions: [GitHub Discussions](https://github.com/your-org/secureshare-sdk/discussions)