Merge branch 'feat/undetected-browser' into develop-future

This commit is contained in:
ntohidi
2025-08-06 15:03:30 +08:00
30 changed files with 5331 additions and 383 deletions

View File

@@ -358,9 +358,77 @@ if __name__ == "__main__":
---
---
## 7. Anti-Bot Features (Stealth Mode & Undetected Browser)
Crawl4AI provides two powerful features to bypass bot detection:
### 7.1 Stealth Mode
Stealth mode uses playwright-stealth to modify browser fingerprints and behaviors. Enable it with a simple flag:
```python
browser_config = BrowserConfig(
enable_stealth=True, # Activates stealth mode
headless=False
)
```
**When to use**: Sites with basic bot detection (checking navigator.webdriver, plugins, etc.)
### 7.2 Undetected Browser
For advanced bot detection, use the undetected browser adapter:
```python
from crawl4ai import UndetectedAdapter
from crawl4ai.async_crawler_strategy import AsyncPlaywrightCrawlerStrategy
# Create undetected adapter
adapter = UndetectedAdapter()
strategy = AsyncPlaywrightCrawlerStrategy(
browser_config=browser_config,
browser_adapter=adapter
)
async with AsyncWebCrawler(crawler_strategy=strategy, config=browser_config) as crawler:
# Your crawling code
```
**When to use**: Sites with sophisticated bot detection (Cloudflare, DataDome, etc.)
### 7.3 Combining Both
For maximum evasion, combine stealth mode with undetected browser:
```python
browser_config = BrowserConfig(
enable_stealth=True, # Enable stealth
headless=False
)
adapter = UndetectedAdapter() # Use undetected browser
```
### Choosing the Right Approach
| Detection Level | Recommended Approach |
|----------------|---------------------|
| No protection | Regular browser |
| Basic checks | Regular + Stealth mode |
| Advanced protection | Undetected browser |
| Maximum evasion | Undetected + Stealth mode |
**Best Practice**: Start with regular browser + stealth mode. Only use undetected browser if needed, as it may be slightly slower.
See [Undetected Browser Mode](undetected-browser.md) for detailed examples.
---
## Conclusion & Next Steps
Youve now explored several **advanced** features:
You've now explored several **advanced** features:
- **Proxy Usage**
- **PDF & Screenshot** capturing for large or critical pages
@@ -368,7 +436,10 @@ Youve now explored several **advanced** features:
- **Custom Headers** for language or specialized requests
- **Session Persistence** via storage state
- **Robots.txt Compliance**
- **Anti-Bot Features** (Stealth Mode & Undetected Browser)
With these power tools, you can build robust scraping workflows that mimic real user behavior, handle secure sites, capture detailed snapshots, and manage sessions across multiple runs—streamlining your entire data collection pipeline.
With these power tools, you can build robust scraping workflows that mimic real user behavior, handle secure sites, capture detailed snapshots, manage sessions across multiple runs, and bypass bot detection—streamlining your entire data collection pipeline.
**Last Updated**: 2025-01-01
**Note**: In future versions, we may enable stealth mode and undetected browser by default. For now, users should explicitly enable these features when needed.
**Last Updated**: 2025-01-17

View File

@@ -0,0 +1,394 @@
# Undetected Browser Mode
## Overview
Crawl4AI offers two powerful anti-bot features to help you access websites with bot detection:
1. **Stealth Mode** - Uses playwright-stealth to modify browser fingerprints and behaviors
2. **Undetected Browser Mode** - Advanced browser adapter with deep-level patches for sophisticated bot detection
This guide covers both features and helps you choose the right approach for your needs.
## Anti-Bot Features Comparison
| Feature | Regular Browser | Stealth Mode | Undetected Browser |
|---------|----------------|--------------|-------------------|
| WebDriver Detection | ❌ | ✅ | ✅ |
| Navigator Properties | ❌ | ✅ | ✅ |
| Plugin Emulation | ❌ | ✅ | ✅ |
| CDP Detection | ❌ | Partial | ✅ |
| Deep Browser Patches | ❌ | ❌ | ✅ |
| Performance Impact | None | Minimal | Moderate |
| Setup Complexity | None | None | Minimal |
## When to Use Each Approach
### Use Regular Browser + Stealth Mode When:
- Sites have basic bot detection (checking navigator.webdriver, plugins, etc.)
- You need good performance with basic protection
- Sites check for common automation indicators
### Use Undetected Browser When:
- Sites employ sophisticated bot detection services (Cloudflare, DataDome, etc.)
- Stealth mode alone isn't sufficient
- You're willing to trade some performance for better evasion
### Best Practice: Progressive Enhancement
1. **Start with**: Regular browser + Stealth mode
2. **If blocked**: Switch to Undetected browser
3. **If still blocked**: Combine Undetected browser + Stealth mode
## Stealth Mode
Stealth mode is the simpler anti-bot solution that works with both regular and undetected browsers:
```python
from crawl4ai import AsyncWebCrawler, BrowserConfig
# Enable stealth mode with regular browser
browser_config = BrowserConfig(
enable_stealth=True, # Simple flag to enable
headless=False # Better for avoiding detection
)
async with AsyncWebCrawler(config=browser_config) as crawler:
result = await crawler.arun("https://example.com")
```
### What Stealth Mode Does:
- Removes `navigator.webdriver` flag
- Modifies browser fingerprints
- Emulates realistic plugin behavior
- Adjusts navigator properties
- Fixes common automation leaks
## Undetected Browser Mode
For sites with sophisticated bot detection that stealth mode can't bypass, use the undetected browser adapter:
### Key Features
- **Drop-in Replacement**: Uses the same API as regular browser mode
- **Enhanced Stealth**: Built-in patches to evade common detection methods
- **Browser Adapter Pattern**: Seamlessly switch between regular and undetected modes
- **Automatic Installation**: `crawl4ai-setup` installs all necessary browser dependencies
### Quick Start
```python
import asyncio
from crawl4ai import (
AsyncWebCrawler,
BrowserConfig,
CrawlerRunConfig,
UndetectedAdapter
)
from crawl4ai.async_crawler_strategy import AsyncPlaywrightCrawlerStrategy
async def main():
# Create the undetected adapter
undetected_adapter = UndetectedAdapter()
# Create browser config
browser_config = BrowserConfig(
headless=False, # Headless mode can be detected easier
verbose=True,
)
# Create the crawler strategy with undetected adapter
crawler_strategy = AsyncPlaywrightCrawlerStrategy(
browser_config=browser_config,
browser_adapter=undetected_adapter
)
# Create the crawler with our custom strategy
async with AsyncWebCrawler(
crawler_strategy=crawler_strategy,
config=browser_config
) as crawler:
# Your crawling code here
result = await crawler.arun(
url="https://example.com",
config=CrawlerRunConfig()
)
print(result.markdown[:500])
asyncio.run(main())
```
## Combining Both Features
For maximum evasion, combine stealth mode with undetected browser:
```python
from crawl4ai import AsyncWebCrawler, BrowserConfig, UndetectedAdapter
from crawl4ai.async_crawler_strategy import AsyncPlaywrightCrawlerStrategy
# Create browser config with stealth enabled
browser_config = BrowserConfig(
enable_stealth=True, # Enable stealth mode
headless=False
)
# Create undetected adapter
adapter = UndetectedAdapter()
# Create strategy with both features
strategy = AsyncPlaywrightCrawlerStrategy(
browser_config=browser_config,
browser_adapter=adapter
)
async with AsyncWebCrawler(
crawler_strategy=strategy,
config=browser_config
) as crawler:
result = await crawler.arun("https://protected-site.com")
```
## Examples
### Example 1: Basic Stealth Mode
```python
import asyncio
from crawl4ai import AsyncWebCrawler, BrowserConfig, CrawlerRunConfig
async def test_stealth_mode():
# Simple stealth mode configuration
browser_config = BrowserConfig(
enable_stealth=True,
headless=False
)
async with AsyncWebCrawler(config=browser_config) as crawler:
result = await crawler.arun(
url="https://bot.sannysoft.com",
config=CrawlerRunConfig(screenshot=True)
)
if result.success:
print("✓ Successfully accessed bot detection test site")
# Save screenshot to verify detection results
if result.screenshot:
import base64
with open("stealth_test.png", "wb") as f:
f.write(base64.b64decode(result.screenshot))
print("✓ Screenshot saved - check for green (passed) tests")
asyncio.run(test_stealth_mode())
```
### Example 2: Undetected Browser Mode
```python
import asyncio
from crawl4ai import (
AsyncWebCrawler,
BrowserConfig,
CrawlerRunConfig,
UndetectedAdapter
)
from crawl4ai.async_crawler_strategy import AsyncPlaywrightCrawlerStrategy
async def main():
# Create browser config
browser_config = BrowserConfig(
headless=False,
verbose=True,
)
# Create the undetected adapter
undetected_adapter = UndetectedAdapter()
# Create the crawler strategy with the undetected adapter
crawler_strategy = AsyncPlaywrightCrawlerStrategy(
browser_config=browser_config,
browser_adapter=undetected_adapter
)
# Create the crawler with our custom strategy
async with AsyncWebCrawler(
crawler_strategy=crawler_strategy,
config=browser_config
) as crawler:
# Configure the crawl
crawler_config = CrawlerRunConfig(
markdown_generator=DefaultMarkdownGenerator(
content_filter=PruningContentFilter()
),
capture_console_messages=True, # Test adapter console capture
)
# Test on a site that typically detects bots
print("Testing undetected adapter...")
result: CrawlResult = await crawler.arun(
url="https://www.helloworld.org",
config=crawler_config
)
print(f"Status: {result.status_code}")
print(f"Success: {result.success}")
print(f"Console messages captured: {len(result.console_messages or [])}")
print(f"Markdown content (first 500 chars):\n{result.markdown.raw_markdown[:500]}")
if __name__ == "__main__":
asyncio.run(main())
```
## Browser Adapter Pattern
The undetected browser support is implemented using an adapter pattern, allowing seamless switching between different browser implementations:
```python
# Regular browser adapter (default)
from crawl4ai import PlaywrightAdapter
regular_adapter = PlaywrightAdapter()
# Undetected browser adapter
from crawl4ai import UndetectedAdapter
undetected_adapter = UndetectedAdapter()
```
The adapter handles:
- JavaScript execution
- Console message capture
- Error handling
- Browser-specific optimizations
## Best Practices
1. **Avoid Headless Mode**: Detection is easier in headless mode
```python
browser_config = BrowserConfig(headless=False)
```
2. **Use Reasonable Delays**: Don't rush through pages
```python
crawler_config = CrawlerRunConfig(
wait_time=3.0, # Wait 3 seconds after page load
delay_before_return_html=2.0 # Additional delay
)
```
3. **Rotate User Agents**: You can customize user agents
```python
browser_config = BrowserConfig(
headers={"User-Agent": "your-user-agent"}
)
```
4. **Handle Failures Gracefully**: Some sites may still detect and block
```python
if not result.success:
print(f"Crawl failed: {result.error_message}")
```
## Advanced Usage Tips
### Progressive Detection Handling
```python
async def crawl_with_progressive_evasion(url):
# Step 1: Try regular browser with stealth
browser_config = BrowserConfig(
enable_stealth=True,
headless=False
)
async with AsyncWebCrawler(config=browser_config) as crawler:
result = await crawler.arun(url)
if result.success and "Access Denied" not in result.html:
return result
# Step 2: If blocked, try undetected browser
print("Regular + stealth blocked, trying undetected browser...")
adapter = UndetectedAdapter()
strategy = AsyncPlaywrightCrawlerStrategy(
browser_config=browser_config,
browser_adapter=adapter
)
async with AsyncWebCrawler(
crawler_strategy=strategy,
config=browser_config
) as crawler:
result = await crawler.arun(url)
return result
```
## Installation
The undetected browser dependencies are automatically installed when you run:
```bash
crawl4ai-setup
```
This command installs all necessary browser dependencies for both regular and undetected modes.
## Limitations
- **Performance**: Slightly slower than regular mode due to additional patches
- **Headless Detection**: Some sites can still detect headless mode
- **Resource Usage**: May use more resources than regular mode
- **Not 100% Guaranteed**: Advanced anti-bot services are constantly evolving
## Troubleshooting
### Browser Not Found
Run the setup command:
```bash
crawl4ai-setup
```
### Detection Still Occurring
Try combining with other features:
```python
crawler_config = CrawlerRunConfig(
simulate_user=True, # Add user simulation
magic=True, # Enable magic mode
wait_time=5.0, # Longer waits
)
```
### Performance Issues
If experiencing slow performance:
```python
# Use selective undetected mode only for protected sites
if is_protected_site(url):
adapter = UndetectedAdapter()
else:
adapter = PlaywrightAdapter() # Default adapter
```
## Future Plans
**Note**: In future versions of Crawl4AI, we may enable stealth mode and undetected browser by default to provide better out-of-the-box success rates. For now, users should explicitly enable these features when needed.
## Conclusion
Crawl4AI provides flexible anti-bot solutions:
1. **Start Simple**: Use regular browser + stealth mode for most sites
2. **Escalate if Needed**: Switch to undetected browser for sophisticated protection
3. **Combine for Maximum Effect**: Use both features together when facing the toughest challenges
Remember:
- Always respect robots.txt and website terms of service
- Use appropriate delays to avoid overwhelming servers
- Consider the performance trade-offs of each approach
- Test progressively to find the minimum necessary evasion level
## See Also
- [Advanced Features](advanced-features.md) - Overview of all advanced features
- [Proxy & Security](proxy-security.md) - Using proxies with anti-bot features
- [Session Management](session-management.md) - Maintaining sessions across requests
- [Identity Based Crawling](identity-based-crawling.md) - Additional anti-detection strategies

View File

@@ -29,6 +29,7 @@ class BrowserConfig:
text_mode=False,
light_mode=False,
extra_args=None,
enable_stealth=False,
# ... other advanced parameters omitted here
):
...
@@ -84,6 +85,11 @@ class BrowserConfig:
- Additional flags for the underlying browser.
- E.g. `["--disable-extensions"]`.
11. **`enable_stealth`**:
- If `True`, enables stealth mode using playwright-stealth.
- Modifies browser fingerprints to avoid basic bot detection.
- Default is `False`. Recommended for sites with bot protection.
### Helper Methods
Both configuration classes provide a `clone()` method to create modified copies:

View File

@@ -54,6 +54,16 @@ This page provides a comprehensive list of example scripts that demonstrate vari
| Crypto Analysis | Demonstrates how to crawl and analyze cryptocurrency data. | [View Code](https://github.com/unclecode/crawl4ai/blob/main/docs/examples/crypto_analysis_example.py) |
| SERP API | Demonstrates using Crawl4AI with search engine result pages. | [View Code](https://github.com/unclecode/crawl4ai/blob/main/docs/examples/serp_api_project_11_feb.py) |
## Anti-Bot & Stealth Features
| Example | Description | Link |
|---------|-------------|------|
| Stealth Mode Quick Start | Five practical examples showing how to use stealth mode for bypassing basic bot detection. | [View Code](https://github.com/unclecode/crawl4ai/blob/main/docs/examples/stealth_mode_quick_start.py) |
| Stealth Mode Comprehensive | Comprehensive demonstration of stealth mode features with bot detection testing and comparisons. | [View Code](https://github.com/unclecode/crawl4ai/blob/main/docs/examples/stealth_mode_example.py) |
| Undetected Browser | Simple example showing how to use the undetected browser adapter. | [View Code](https://github.com/unclecode/crawl4ai/blob/main/docs/examples/hello_world_undetected.py) |
| Undetected Browser Demo | Basic demo comparing regular and undetected browser modes. | [View Code](https://github.com/unclecode/crawl4ai/blob/main/docs/examples/undetected_simple_demo.py) |
| Undetected Tests | Advanced tests comparing regular vs undetected browsers on various bot detection services. | [View Folder](https://github.com/unclecode/crawl4ai/tree/main/docs/examples/undetectability/) |
## Customization & Security
| Example | Description | Link |

View File

@@ -18,7 +18,7 @@ crawl4ai-setup
```
**What does it do?**
- Installs or updates required Playwright browsers (Chromium, Firefox, etc.)
- Installs or updates required browser dependencies for both regular and undetected modes
- Performs OS-level checks (e.g., missing libs on Linux)
- Confirms your environment is ready to crawl