ferrisfetcher 0.1.0

# FerrisFetcher Project Instructions


## Overview


FerrisFetcher is a cutting-edge, high-level web scraping library crafted in Rust. The library leverages Tokio's asynchronous prowess for concurrent operations and Reqwest's efficient HTTP handling to provide a powerful, performant, and user-friendly web scraping solution.

## Project Architecture


### Core Components


#### 1. HTTP Client Module

- **Purpose**: Handle HTTP requests with robust error handling and retry mechanisms
- **Dependencies**: Reqwest, Tokio
- **Features**: 
  - Async HTTP client with connection pooling
  - Custom headers and user agent management
  - Rate limiting and respectful scraping practices
  - Proxy support
  - Cookie management

#### 2. HTML Parsing Module

- **Purpose**: Parse and manipulate HTML documents efficiently
- **Dependencies**: Scraper, html5ever, or similar
- **Features**:
  - CSS selector-based element extraction
  - DOM traversal and manipulation
  - Text cleaning and normalization
  - Support for malformed HTML

#### 3. Data Extraction Engine

- **Purpose**: Extract structured data from web pages
- **Features**:
  - Configurable extraction rules
  - Type-safe data structures
  - Pagination handling
  - Form submission support

#### 4. Concurrency Manager

- **Purpose**: Manage concurrent scraping operations
- **Dependencies**: Tokio, async-trait
- **Features**:
  - Configurable concurrency limits
  - Task scheduling and queuing
  - Resource management
  - Error isolation and recovery

#### 5. Storage Abstraction Layer

- **Purpose**: Provide flexible data storage options
- **Features**:
  - JSON output support
  - CSV export capabilities
  - Database integration (optional)
  - File system storage

## API Design


### Core API Structure


```rust
// Main scraper interface
pub struct FerrisFetcher {
    client: HttpClient,
    parser: HtmlParser,
    extractor: DataExtractor,
    concurrency: ConcurrencyManager,
}

impl FerrisFetcher {
    pub fn new() -> Self;
    pub fn with_config(config: Config) -> Self;
    pub async fn scrape(&self, url: &str) -> Result<ScrapedData>;
    pub async fn scrape_multiple(&self, urls: Vec<&str>) -> Result<Vec<ScrapedData>>;
}
```

### Configuration System


```rust
pub struct Config {
    pub user_agent: String,
    pub timeout: Duration,
    pub max_concurrent_requests: usize,
    pub rate_limit: Option<Duration>,
    pub retry_policy: RetryPolicy,
    pub headers: HeaderMap,
}
```

### Data Structures


```rust
#[derive(Debug, Clone, Serialize, Deserialize)]

pub struct ScrapedData {
    pub url: String,
    pub title: Option<String>,
    pub content: String,
    pub metadata: HashMap<String, Value>,
    pub extracted_data: HashMap<String, Vec<String>>,
    pub timestamp: DateTime<Utc>,
}
```

## Implementation Roadmap


### Phase 1: Foundation (Week 1-2)

- [ ] Set up Cargo project structure
- [ ] Implement basic HTTP client with Reqwest
- [ ] Create error handling types and Result patterns
- [ ] Add basic logging infrastructure
- [ ] Write initial unit tests

### Phase 2: Core Functionality (Week 3-4)

- [ ] Implement HTML parsing module
- [ ] Create CSS selector engine
- [ ] Build data extraction framework
- [ ] Add configuration management
- [ ] Implement basic scraping workflow

### Phase 3: Advanced Features (Week 5-6)

- [ ] Add concurrency management with Tokio
- [ ] Implement rate limiting and respectful scraping
- [ ] Create pagination handling system
- [ ] Add form submission capabilities
- [ ] Implement retry mechanisms

### Phase 4: Storage & Export (Week 7-8)

- [ ] Create storage abstraction layer
- [ ] Implement JSON/CSV export
- [ ] Add database integration options
- [ ] Create data transformation utilities
- [ ] Add streaming data export

### Phase 5: Optimization & Polish (Week 9-10)

- [ ] Performance optimization and benchmarking
- [ ] Memory usage optimization
- [ ] Add comprehensive error messages
- [ ] Improve API documentation
- [ ] Add integration tests

## Quality Assurance


### Testing Strategy

- **Unit Tests**: 90%+ code coverage for core modules
- **Integration Tests**: End-to-end scraping workflows
- **Performance Tests**: Benchmark against common scraping scenarios
- **Property-based Tests**: Validate data extraction accuracy

### Documentation Requirements

- **API Documentation**: Comprehensive rustdoc examples
- **User Guide**: Step-by-step usage tutorials
- **Examples Repository**: Real-world scraping examples
- **Changelog**: Detailed version history and migration guides

### Code Quality Standards

- **Formatting**: Use `rustfmt` for consistent code style
- **Linting**: Use `clippy` for code quality checks
- **Dependencies**: Minimal, well-maintained dependencies
- **Security**: Regular security audits and dependency updates

## Performance Targets


### Benchmarks

- **Single Request**: < 100ms average response time
- **Concurrent Requests**: Handle 100+ concurrent connections
- **Memory Usage**: < 50MB for typical scraping workloads
- **CPU Efficiency**: Minimal CPU overhead during I/O operations

### Scalability

- **Large-scale Scraping**: Support for 10,000+ page scraping jobs
- **Memory Management**: Efficient memory usage for large datasets
- **Error Recovery**: Graceful handling of network failures and timeouts

## Security Considerations


### Respectful Scraping

- **Rate Limiting**: Configurable delays between requests
- **User Agent**: Proper identification of the scraper
- **Robots.txt**: Compliance with website scraping policies
- **Headers**: Custom headers for authentication and identification

### Data Privacy

- **PII Detection**: Optional detection of personally identifiable information
- **Data Sanitization**: Built-in data cleaning capabilities
- **Secure Storage**: Options for encrypted data storage

## Community & Ecosystem


### Crate Features

- **Default**: Basic scraping functionality
- **Full**: All features including database support
- **Minimal**: Core functionality only for embedded use

### Integration Examples

- **CLI Tool**: Command-line interface for quick scraping tasks
- **Web Service**: REST API wrapper for remote scraping
- **Desktop App**: GUI application for non-technical users

## Release Strategy


### Version Management

- **Semantic Versioning**: Follow SemVer for version numbering
- **Release Cadence**: Regular releases with clear changelogs
- **Backward Compatibility**: Maintain API stability within major versions

### Distribution

- **crates.io**: Primary distribution channel
- **GitHub Releases**: Source code and binary distributions
- **Documentation**: Comprehensive docs.rs integration

## Contributing Guidelines


### Development Workflow

1. Fork the repository
2. Create feature branch with descriptive name
3. Implement changes with comprehensive tests
4. Ensure all tests pass and code quality checks pass
5. Submit pull request with detailed description

### Code Review Process

- **Automated Checks**: CI/CD pipeline with tests and linting
- **Manual Review**: At least one maintainer approval required
- **Documentation**: Update docs for all API changes

## Support & Maintenance


### Issue Triage

- **Bug Reports**: Priority based on severity and impact
- **Feature Requests**: Evaluated against project goals
- **Security Issues**: Private reporting and rapid response

### Long-term Maintenance

- **Dependency Updates**: Regular updates and compatibility testing
- **Rust Edition**: Keep up with Rust language updates
- **Community Support**: Active response to user questions and issues

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This project aims to become the go-to web scraping solution in the Rust ecosystem, combining performance, safety, and ease of use while maintaining the highest standards of code quality and community engagement.