Files
crawl4ai/docs/md_v2/advanced/proxy-security.md
2025-11-13 09:23:44 +01:00

305 lines
9.7 KiB
Markdown

# Proxy & Security
This guide covers proxy configuration and security features in Crawl4AI, including SSL certificate analysis and proxy rotation strategies.
## Understanding Proxy Configuration
Crawl4AI recommends configuring proxies per request through `CrawlerRunConfig.proxy_config`. This gives you precise control, enables rotation strategies, and keeps examples simple enough to copy, paste, and run.
## Basic Proxy Setup
Configure proxies that apply to each crawl operation:
```python
import asyncio
from crawl4ai import AsyncWebCrawler, BrowserConfig, CrawlerRunConfig, ProxyConfig
run_config = CrawlerRunConfig(proxy_config=ProxyConfig(server="http://proxy.example.com:8080"))
# run_config = CrawlerRunConfig(proxy_config={"server": "http://proxy.example.com:8080"})
# run_config = CrawlerRunConfig(proxy_config="http://proxy.example.com:8080")
async def main():
browser_config = BrowserConfig()
async with AsyncWebCrawler(config=browser_config) as crawler:
result = await crawler.arun(url="https://example.com", config=run_config)
print(f"Success: {result.success} -> {result.url}")
if __name__ == "__main__":
asyncio.run(main())
```
!!! note "Why request-level?"
`CrawlerRunConfig.proxy_config` keeps each request self-contained, so swapping proxies or rotation strategies is just a matter of building a new run configuration.
## Supported Proxy Formats
The `ProxyConfig.from_string()` method supports multiple formats:
```python
from crawl4ai import ProxyConfig
# HTTP proxy with authentication
proxy1 = ProxyConfig.from_string("http://user:pass@192.168.1.1:8080")
# HTTPS proxy
proxy2 = ProxyConfig.from_string("https://proxy.example.com:8080")
# SOCKS5 proxy
proxy3 = ProxyConfig.from_string("socks5://proxy.example.com:1080")
# Simple IP:port format
proxy4 = ProxyConfig.from_string("192.168.1.1:8080")
# IP:port:user:pass format
proxy5 = ProxyConfig.from_string("192.168.1.1:8080:user:pass")
```
## Authenticated Proxies
For proxies requiring authentication:
```python
import asyncio
from crawl4ai import AsyncWebCrawler,BrowserConfig, CrawlerRunConfig, ProxyConfig
run_config = CrawlerRunConfig(
proxy_config=ProxyConfig(
server="http://proxy.example.com:8080",
username="your_username",
password="your_password",
)
)
# Or dictionary style:
# run_config = CrawlerRunConfig(proxy_config={
# "server": "http://proxy.example.com:8080",
# "username": "your_username",
# "password": "your_password",
# })
async def main():
browser_config = BrowserConfig()
async with AsyncWebCrawler(config=browser_config) as crawler:
result = await crawler.arun(url="https://example.com", config=run_config)
print(f"Success: {result.success} -> {result.url}")
if __name__ == "__main__":
asyncio.run(main())
```
## Environment Variable Configuration
Load proxies from environment variables for easy configuration:
```python
import os
from crawl4ai import ProxyConfig, CrawlerRunConfig
# Set environment variable
os.environ["PROXIES"] = "ip1:port1:user1:pass1,ip2:port2:user2:pass2,ip3:port3"
# Load all proxies
proxies = ProxyConfig.from_env()
print(f"Loaded {len(proxies)} proxies")
# Use first proxy
if proxies:
run_config = CrawlerRunConfig(proxy_config=proxies[0])
```
## Rotating Proxies
Crawl4AI supports automatic proxy rotation to distribute requests across multiple proxy servers. Rotation is applied per request using a rotation strategy on `CrawlerRunConfig`.
### Proxy Rotation (recommended)
```python
import asyncio
import re
from crawl4ai import AsyncWebCrawler, BrowserConfig, CrawlerRunConfig, CacheMode, ProxyConfig
from crawl4ai.proxy_strategy import RoundRobinProxyStrategy
async def main():
# Load proxies from environment
proxies = ProxyConfig.from_env()
if not proxies:
print("No proxies found! Set PROXIES environment variable.")
return
# Create rotation strategy
proxy_strategy = RoundRobinProxyStrategy(proxies)
# Configure per-request with proxy rotation
browser_config = BrowserConfig(headless=True, verbose=False)
run_config = CrawlerRunConfig(
cache_mode=CacheMode.BYPASS,
proxy_rotation_strategy=proxy_strategy,
)
async with AsyncWebCrawler(config=browser_config) as crawler:
urls = ["https://httpbin.org/ip"] * (len(proxies) * 2) # Test each proxy twice
print(f"🚀 Testing {len(proxies)} proxies with rotation...")
results = await crawler.arun_many(urls=urls, config=run_config)
for i, result in enumerate(results):
if result.success:
# Extract IP from response
ip_match = re.search(r'(?:[0-9]{1,3}\.){3}[0-9]{1,3}', result.html)
if ip_match:
detected_ip = ip_match.group(0)
proxy_index = i % len(proxies)
expected_ip = proxies[proxy_index].ip
print(f"✅ Request {i+1}: Proxy {proxy_index+1} -> IP {detected_ip}")
if detected_ip == expected_ip:
print(" 🎯 IP matches proxy configuration")
else:
print(f" ⚠️ IP mismatch (expected {expected_ip})")
else:
print(f"❌ Request {i+1}: Could not extract IP from response")
else:
print(f"❌ Request {i+1}: Failed - {result.error_message}")
if __name__ == "__main__":
asyncio.run(main())
```
## SSL Certificate Analysis
Combine proxy usage with SSL certificate inspection for enhanced security analysis. SSL certificate fetching is configured per request via `CrawlerRunConfig`.
### Per-Request SSL Certificate Analysis
```python
import asyncio
from crawl4ai import AsyncWebCrawler, BrowserConfig, CrawlerRunConfig
run_config = CrawlerRunConfig(
proxy_config={
"server": "http://proxy.example.com:8080",
"username": "user",
"password": "pass",
},
fetch_ssl_certificate=True, # Enable SSL certificate analysis for this request
)
async def main():
browser_config = BrowserConfig()
async with AsyncWebCrawler(config=browser_config) as crawler:
result = await crawler.arun(url="https://example.com", config=run_config)
if result.success:
print(f"✅ Crawled via proxy: {result.url}")
# Analyze SSL certificate
if result.ssl_certificate:
cert = result.ssl_certificate
print("🔒 SSL Certificate Info:")
print(f" Issuer: {cert.issuer}")
print(f" Subject: {cert.subject}")
print(f" Valid until: {cert.valid_until}")
print(f" Fingerprint: {cert.fingerprint}")
# Export certificate
cert.to_json("certificate.json")
print("💾 Certificate exported to certificate.json")
else:
print("⚠️ No SSL certificate information available")
if __name__ == "__main__":
asyncio.run(main())
```
## Security Best Practices
### 1. Proxy Rotation for Anonymity
```python
from crawl4ai import CrawlerRunConfig, ProxyConfig
from crawl4ai.proxy_strategy import RoundRobinProxyStrategy
# Use multiple proxies to avoid IP blocking
proxies = ProxyConfig.from_env("PROXIES")
strategy = RoundRobinProxyStrategy(proxies)
# Configure rotation per request (recommended)
run_config = CrawlerRunConfig(proxy_rotation_strategy=strategy)
# For a fixed proxy across all requests, just reuse the same run_config instance
static_run_config = run_config
```
### 2. SSL Certificate Verification
```python
from crawl4ai import CrawlerRunConfig
# Always verify SSL certificates when possible
# Per-request (affects specific requests)
run_config = CrawlerRunConfig(fetch_ssl_certificate=True)
```
### 3. Environment Variable Security
```bash
# Use environment variables for sensitive proxy credentials
# Avoid hardcoding usernames/passwords in code
export PROXIES="ip1:port1:user1:pass1,ip2:port2:user2:pass2"
```
### 4. SOCKS5 for Enhanced Security
```python
from crawl4ai import CrawlerRunConfig
# Prefer SOCKS5 proxies for better protocol support
run_config = CrawlerRunConfig(proxy_config="socks5://proxy.example.com:1080")
```
## Migration from Deprecated `proxy` Parameter
- "Deprecation Notice"
The legacy `proxy` argument on `BrowserConfig` is deprecated. Configure proxies through `CrawlerRunConfig.proxy_config` so each request fully describes its network settings.
```python
# Old (deprecated) approach
# from crawl4ai import BrowserConfig
# browser_config = BrowserConfig(proxy="http://proxy.example.com:8080")
# New (preferred) approach
from crawl4ai import CrawlerRunConfig
run_config = CrawlerRunConfig(proxy_config="http://proxy.example.com:8080")
```
### Safe Logging of Proxies
```python
from crawl4ai import ProxyConfig
def safe_proxy_repr(proxy: ProxyConfig):
if getattr(proxy, "username", None):
return f"{proxy.server} (auth: ****)"
return proxy.server
```
## Troubleshooting
### Common Issues
- "Proxy connection failed"
- Verify the proxy server is reachable from your network.
- Double-check authentication credentials.
- Ensure the protocol matches (`http`, `https`, or `socks5`).
- "SSL certificate errors"
- Some proxies break SSL inspection; switch proxies if you see repeated failures.
- Consider temporarily disabling certificate fetching to isolate the issue.
- "Environment variables not loading"
- Confirm `PROXIES` (or your custom env var) is set before running the script.
- Check formatting: `ip:port:user:pass,ip:port:user:pass`.
- "Proxy rotation not working"
- Ensure `ProxyConfig.from_env()` actually loaded entries (`len(proxies) > 0`).
- Attach `proxy_rotation_strategy` to `CrawlerRunConfig`.
- Validate the proxy definitions you pass into the strategy.