Crawl4ai

Fixed
- Added support for parsing Base64 encoded images in WebScrapingStrategy

Added
- Forked and integrated a customized version of the html2text library for more control over Markdown generation
- New configuration options for controlling external content:
- Ability to exclude all external links
- Option to specify domains to exclude (default includes major social media platforms)
- Control over excluding external images

Changed
- Improved Markdown generation process:
- Added fine-grained control over character escaping in Markdown output
- Enhanced handling of code blocks and pre-formatted text
- Updated `AsyncPlaywrightCrawlerStrategy.close()` method to use a shorter sleep time (0.5 seconds instead of 500)
- Enhanced flexibility in `CosineStrategy` with a more generic `load_HF_embedding_model` function

Improved
- Optimized content scraping and processing for better efficiency
- Enhanced error handling and logging in various components

Developer Notes
- The customized html2text library is now located within the crawl4ai package
- New configuration options are available in the `config.py` file for external content handling
- The `WebScrapingStrategy` class has been updated to accommodate new external content exclusion options

Changes
1. **Version Update**:
- Updated version number from 0.3.7 to 0.3.71.

2. **Crawler Enhancements**:
- Added `sleep_on_close` option to AsyncPlaywrightCrawlerStrategy for delayed browser closure.
- Improved context creation with additional options:
- Enabled `accept_downloads` and `java_script_enabled`.
- Added a cookie to enable cookies by default.

3. **Error Handling Improvements**:
- Enhanced error messages in AsyncWebCrawler's `arun` method.
- Updated error reporting format for better visibility and consistency.

4. **Performance Optimization**:
- Commented out automatic page and context closure in `crawl` method to potentially improve performance in certain scenarios.

Documentation
- Updated quickstart notebook:
- Changed installation command to use the released package instead of GitHub repository.
- Updated kernel display name.

Developer Notes
- Minor code refactoring and cleanup.

New Features
1. **Enhanced Browser Stealth**:
- Implemented `playwright_stealth` for improved bot detection avoidance.
- Added `StealthConfig` for fine-tuned control over stealth parameters.

2. **User Simulation**:
- New `simulate_user` option to mimic human-like interactions (mouse movements, clicks, keyboard presses).

3. **Navigator Override**:
- Added `override_navigator` option to modify navigator properties, further improving bot detection evasion.

4. **Improved iframe Handling**:
- New `process_iframes` parameter to extract and integrate iframe content into the main page.

5. **Flexible Browser Selection**:
- Support for choosing between Chromium, Firefox, and WebKit browsers.

6. **Include Links in Markdown**:
- Added support for including links in Markdown content, by definin g a new flag `include_links_on_markdown` in `crawl` method.

Improvements
1. **Better Error Handling**:
- Enhanced error reporting in WebScrapingStrategy with detailed error messages and suggestions.
- Added console message and error logging for better debugging.

2. **Image Processing Enhancements**:
- Improved image dimension updating and filtering logic.

3. **Crawling Flexibility**:
- Added support for custom viewport sizes.
- Implemented delayed content retrieval with `delay_before_return_html` parameter.

4. **Performance Optimization**:
- Adjusted default semaphore count for parallel crawling.

Bug Fixes
- Fixed an issue where the HTML content could be empty after processing.

Examples
- Added new example `crawl_with_user_simulation()` demonstrating the use of user simulation and navigator override features.

Developer Notes
- Refactored code for better maintainability and readability.
- Updated browser launch arguments for improved compatibility and performance.

1. Improved Crawling Control
- **New Hook**: Added `before_retrieve_html` hook in `AsyncPlaywrightCrawlerStrategy`.
- **Delayed HTML Retrieval**: Introduced `delay_before_return_html` parameter to allow waiting before retrieving HTML content.
- Useful for pages with delayed content loading.
- **Flexible Timeout**: `smart_wait` function now uses `page_timeout` (default 60 seconds) instead of a fixed 30-second timeout.
- Provides better handling for slow-loading pages.
- **How to use**: Set `page_timeout=your_desired_timeout` (in milliseconds) when calling `crawler.arun()`.

2. Browser Type Selection
- Added support for different browser types (Chromium, Firefox, WebKit).
- Users can now specify the browser type when initializing AsyncWebCrawler.
- **How to use**: Set `browser_type="firefox"` or `browser_type="webkit"` when initializing AsyncWebCrawler.

3. Screenshot Capture
- Added ability to capture screenshots during crawling.
- Useful for debugging and content verification.
- **How to use**: Set `screenshot=True` when calling `crawler.arun()`.

4. Enhanced LLM Extraction Strategy
- Added support for multiple LLM providers (OpenAI, Hugging Face, Ollama).
- **Custom Arguments**: Added support for passing extra arguments to LLM providers via `extra_args` parameter.
- **Custom Headers**: Users can now pass custom headers to the extraction strategy.
- **How to use**: Specify the desired provider and custom arguments when using `LLMExtractionStrategy`.

5. iframe Content Extraction
- New feature to process and extract content from iframes.
- **How to use**: Set `process_iframes=True` in the crawl method.

6. Delayed Content Retrieval
- Introduced `get_delayed_content` method in `AsyncCrawlResponse`.
- Allows retrieval of content after a specified delay, useful for dynamically loaded content.
- **How to use**: Access `result.get_delayed_content(delay_in_seconds)` after crawling.

Improvements and Optimizations

1. AsyncWebCrawler Enhancements
- **Flexible Initialization**: Now accepts arbitrary keyword arguments, passed directly to the crawler strategy.
- Allows for more customized setups.

2. Image Processing Optimization
- Enhanced image handling in WebScrapingStrategy.
- Added filtering for small, invisible, or irrelevant images.
- Improved image scoring system for better content relevance.
- Implemented JavaScript-based image dimension updating for more accurate representation.

3. Database Schema Auto-updates
- Automatic database schema updates ensure compatibility with the latest version.

4. Enhanced Error Handling and Logging
- Improved error messages and logging for easier debugging.

5. Content Extraction Refinements
- Refined HTML sanitization process.
- Improved handling of base64 encoded images.
- Enhanced Markdown conversion process.
- Optimized content extraction algorithms.

6. Utility Function Enhancements
- `perform_completion_with_backoff` function now supports additional arguments for more customized API calls to LLM providers.

Bug Fixes
- Fixed an issue where image tags were being prematurely removed during content extraction.

Examples and Documentation
- Updated `quickstart_async.py` with examples of:
- Using custom headers in LLM extraction.
- Different LLM provider usage (OpenAI, Hugging Face, Ollama).
- Custom browser type usage.

Developer Notes
- Refactored code for better maintainability, flexibility, and performance.
- Enhanced type hinting throughout the codebase for improved development experience.
- Expanded error handling for more robust operation.

These updates significantly enhance the flexibility, accuracy, and robustness of crawl4ai, providing users with more control and options for their web crawling and content extraction tasks.

Enhance AsyncWebCrawler with smart waiting and screenshot capabilities

- Implement smart_wait function in AsyncPlaywrightCrawlerStrategy
- Add screenshot support to AsyncCrawlResponse and AsyncWebCrawler
- Improve error handling and timeout management in crawling process
- Fix typo in CrawlResult model (responser_headers -> response_headers)

Significant improvements in text processing and performance:

- 🚀 **Dependency reduction**: Removed dependency on spaCy model for text chunk labeling in cosine extraction strategy.
- 🤖 **Transformer upgrade**: Implemented text sequence classification using a transformer model for labeling text chunks.
- ⚡ **Performance enhancement**: Improved model loading speed due to removal of spaCy dependency.
- 🔧 **Future-proofing**: Laid groundwork for potential complete removal of spaCy dependency in future versions.

These changes address issue 68 and provide a foundation for faster, more efficient text processing in Crawl4AI.