Release v0.8.0: Crash Recovery, Prefetch Mode & Security Fixes (#1712)

* Fix: Use correct URL variable for raw HTML extraction (#1116)

- Prevents full HTML content from being passed as URL to extraction strategies
- Added unit tests to verify raw HTML and regular URL processing

Fix: Wrong URL variable used for extraction of raw html

* Fix #1181: Preserve whitespace in code blocks during HTML scraping

  The remove_empty_elements_fast() method was removing whitespace-only
  span elements inside <pre> and <code> tags, causing import statements
  like "import torch" to become "importtorch". Now skips elements inside
  code blocks where whitespace is significant.

* Refactor Pydantic model configuration to use ConfigDict for arbitrary types

* Fix EmbeddingStrategy: Uncomment response handling for the variations and clean up mock data. ref #1621

* Fix: permission issues with .cache/url_seeder and other runtime cache dirs. ref #1638

* fix: ensure BrowserConfig.to_dict serializes proxy_config

* feat: make LLM backoff configurable end-to-end

- extend LLMConfig with backoff delay/attempt/factor fields and thread them
  through LLMExtractionStrategy, LLMContentFilter, table extraction, and
  Docker API handlers
- expose the backoff parameter knobs on perform_completion_with_backoff/aperform_completion_with_backoff
  and document them in the md_v2 guides

* reproduced AttributeError from #1642

* pass timeout parameter to docker client request

* added missing deep crawling objects to init

* generalized query in ContentRelevanceFilter to be a str or list

* import modules from enhanceable deserialization

* parameterized tests

* Fix: capture current page URL to reflect JavaScript navigation and add test for delayed redirects. ref #1268

* refactor: replace PyPDF2 with pypdf across the codebase. ref #1412

* Add browser_context_id and target_id parameters to BrowserConfig

Enable Crawl4AI to connect to pre-created CDP browser contexts, which is
essential for cloud browser services that pre-create isolated contexts.

Changes:
- Add browser_context_id and target_id parameters to BrowserConfig
- Update from_kwargs() and to_dict() methods
- Modify BrowserManager.start() to use existing context when provided
- Add _get_page_by_target_id() helper method
- Update get_page() to handle pre-existing targets
- Add test for browser_context_id functionality

This enables cloud services to:
1. Create isolated CDP contexts before Crawl4AI connects
2. Pass context/target IDs to BrowserConfig
3. Have Crawl4AI reuse existing contexts instead of creating new ones

* Add cdp_cleanup_on_close flag to prevent memory leaks in cloud/server scenarios

* Fix: add cdp_cleanup_on_close to from_kwargs

* Fix: find context by target_id for concurrent CDP connections

* Fix: use target_id to find correct page in get_page

* Fix: use CDP to find context by browserContextId for concurrent sessions

* Revert context matching attempts - Playwright cannot see CDP-created contexts

* Add create_isolated_context flag for concurrent CDP crawls

When True, forces creation of a new browser context instead of reusing
the default context. Essential for concurrent crawls on the same browser
to prevent navigation conflicts.

* Add context caching to create_isolated_context branch

Uses contexts_by_config cache (same as non-CDP mode) to reuse contexts
for multiple URLs with same config. Still creates new page per crawl
for navigation isolation. Benefits batch/deep crawls.

* Add init_scripts support to BrowserConfig for pre-page-load JS injection

This adds the ability to inject JavaScript that runs before any page loads,
useful for stealth evasions (canvas/audio fingerprinting, userAgentData).

- Add init_scripts parameter to BrowserConfig (list of JS strings)
- Apply init_scripts in setup_context() via context.add_init_script()
- Update from_kwargs() and to_dict() for serialization

* Fix CDP connection handling: support WS URLs and proper cleanup

Changes to browser_manager.py:

1. _verify_cdp_ready(): Support multiple URL formats
   - WebSocket URLs (ws://, wss://): Skip HTTP verification, Playwright handles directly
   - HTTP URLs with query params: Properly parse with urlparse to preserve query string
   - Fixes issue where naive f"{cdp_url}/json/version" broke WS URLs and query params

2. close(): Proper cleanup when cdp_cleanup_on_close=True
   - Close all sessions (pages)
   - Close all contexts
   - Call browser.close() to disconnect (doesn't terminate browser, just releases connection)
   - Wait 1 second for CDP connection to fully release
   - Stop Playwright instance to prevent memory leaks

This enables:
- Connecting to specific browsers via WS URL
- Reusing the same browser with multiple sequential connections
- No user wait needed between connections (internal 1s delay handles it)

Added tests/browser/test_cdp_cleanup_reuse.py with comprehensive tests.

* Update gitignore

* Some debugging for caching

* Add _generate_screenshot_from_html for raw: and file:// URLs

Implements the missing method that was being called but never defined.
Now raw: and file:// URLs can generate screenshots by:
1. Loading HTML into a browser page via page.set_content()
2. Taking screenshot using existing take_screenshot() method
3. Cleaning up the page afterward

This enables cached HTML to be rendered with screenshots in crawl4ai-cloud.

* Add PDF and MHTML support for raw: and file:// URLs

- Replace _generate_screenshot_from_html with _generate_media_from_html
- New method handles screenshot, PDF, and MHTML in one browser session
- Update raw: and file:// URL handlers to use new method
- Enables cached HTML to generate all media types

* Add crash recovery for deep crawl strategies

Add optional resume_state and on_state_change parameters to all deep
crawl strategies (BFS, DFS, Best-First) for cloud deployment crash
recovery.

Features:
- resume_state: Pass saved state to resume from checkpoint
- on_state_change: Async callback fired after each URL for real-time
  state persistence to external storage (Redis, DB, etc.)
- export_state(): Get last captured state manually
- Zero overhead when features are disabled (None defaults)

State includes visited URLs, pending queue/stack, depths, and
pages_crawled count. All state is JSON-serializable.

* Fix: HTTP strategy raw: URL parsing truncates at # character

The AsyncHTTPCrawlerStrategy.crawl() method used urlparse() to extract
content from raw: URLs. This caused HTML with CSS color codes like #eee
to be truncated because # is treated as a URL fragment delimiter.

Before: raw:body{background:#eee} -> parsed.path = 'body{background:'
After:  raw:body{background:#eee} -> raw_content = 'body{background:#eee'

Fix: Strip the raw: or raw:// prefix directly instead of using urlparse,
matching how the browser strategy handles it.

* Add base_url parameter to CrawlerRunConfig for raw HTML processing

When processing raw: HTML (e.g., from cache), the URL parameter is meaningless
for markdown link resolution. This adds a base_url parameter that can be set
explicitly to provide proper URL resolution context.

Changes:
- Add base_url parameter to CrawlerRunConfig.__init__
- Add base_url to CrawlerRunConfig.from_kwargs
- Update aprocess_html to use base_url for markdown generation

Usage:
  config = CrawlerRunConfig(base_url='https://example.com')
  result = await crawler.arun(url='raw:{html}', config=config)

* Add prefetch mode for two-phase deep crawling

- Add `prefetch` parameter to CrawlerRunConfig
- Add `quick_extract_links()` function for fast link extraction
- Add short-circuit in aprocess_html() for prefetch mode
- Add 42 tests (unit, integration, regression)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* Updates on proxy rotation and proxy configuration

* Add proxy support to HTTP crawler strategy

* Add browser pipeline support for raw:/file:// URLs

- Add process_in_browser parameter to CrawlerRunConfig
- Route raw:/file:// URLs through _crawl_web() when browser operations needed
- Use page.set_content() instead of goto() for local content
- Fix cookie handling for non-HTTP URLs in browser_manager
- Auto-detect browser requirements: js_code, wait_for, screenshot, etc.
- Maintain fast path for raw:/file:// without browser params

Fixes #310

* Add smart TTL cache for sitemap URL seeder

- Add cache_ttl_hours and validate_sitemap_lastmod params to SeedingConfig
- New JSON cache format with metadata (version, created_at, lastmod, url_count)
- Cache validation by TTL expiry and sitemap lastmod comparison
- Auto-migration from old .jsonl to new .json format
- Fixes bug where incomplete cache was used indefinitely

* Update URL seeder docs with smart TTL cache parameters

- Add cache_ttl_hours and validate_sitemap_lastmod to parameter table
- Document smart TTL cache validation with examples
- Add cache-related troubleshooting entries
- Update key features summary

* Add MEMORY.md to gitignore

* Docs: Add multi-sample schema generation section

Add documentation explaining how to pass multiple HTML samples
to generate_schema() for stable selectors that work across pages
with varying DOM structures.

Includes:
- Problem explanation (fragile nth-child selectors)
- Solution with code example
- Key points for multi-sample queries
- Comparison table of fragile vs stable selectors

* Fix critical RCE and LFI vulnerabilities in Docker API deployment

Security fixes for vulnerabilities reported by ProjectDiscovery:

1. Remote Code Execution via Hooks (CVE pending)
   - Remove __import__ from allowed_builtins in hook_manager.py
   - Prevents arbitrary module imports (os, subprocess, etc.)
   - Hooks now disabled by default via CRAWL4AI_HOOKS_ENABLED env var

2. Local File Inclusion via file:// URLs (CVE pending)
   - Add URL scheme validation to /execute_js, /screenshot, /pdf, /html
   - Block file://, javascript:, data: and other dangerous schemes
   - Only allow http://, https://, and raw: (where appropriate)

3. Security hardening
   - Add CRAWL4AI_HOOKS_ENABLED=false as default (opt-in for hooks)
   - Add security warning comments in config.yml
   - Add validate_url_scheme() helper for consistent validation

Testing:
   - Add unit tests (test_security_fixes.py) - 16 tests
   - Add integration tests (run_security_tests.py) for live server

Affected endpoints:
   - POST /crawl (hooks disabled by default)
   - POST /crawl/stream (hooks disabled by default)
   - POST /execute_js (URL validation added)
   - POST /screenshot (URL validation added)
   - POST /pdf (URL validation added)
   - POST /html (URL validation added)

Breaking changes:
   - Hooks require CRAWL4AI_HOOKS_ENABLED=true to function
   - file:// URLs no longer work on API endpoints (use library directly)

* Enhance authentication flow by implementing JWT token retrieval and adding authorization headers to API requests

* Add release notes for v0.7.9, detailing breaking changes, security fixes, new features, bug fixes, and documentation updates

* Add release notes for v0.8.0, detailing breaking changes, security fixes, new features, bug fixes, and documentation updates

Documentation for v0.8.0 release:

- SECURITY.md: Security policy and vulnerability reporting guidelines
- RELEASE_NOTES_v0.8.0.md: Comprehensive release notes
- migration/v0.8.0-upgrade-guide.md: Step-by-step migration guide
- security/GHSA-DRAFT-RCE-LFI.md: GitHub security advisory drafts
- CHANGELOG.md: Updated with v0.8.0 changes

Breaking changes documented:
- Docker API hooks disabled by default (CRAWL4AI_HOOKS_ENABLED)
- file:// URLs blocked on Docker API endpoints

Security fixes credited to Neo by ProjectDiscovery

* Add examples for deep crawl crash recovery and prefetch mode in documentation

* Release v0.8.0: The v0.8.0 Update

- Updated version to 0.8.0
- Added comprehensive demo and release notes
- Updated all documentation

* Update security researcher acknowledgment with a hyperlink for Neo by ProjectDiscovery

* Add async agenerate_schema method for schema generation

- Extract prompt building to shared _build_schema_prompt() method
- Add agenerate_schema() async version using aperform_completion_with_backoff
- Refactor generate_schema() to use shared prompt builder
- Fixes Gemini/Vertex AI compatibility in async contexts (FastAPI)

* Fix: Enable litellm.drop_params for O-series/GPT-5 model compatibility

O-series (o1, o3) and GPT-5 models only support temperature=1.
Setting litellm.drop_params=True auto-drops unsupported parameters
instead of throwing UnsupportedParamsError.

Fixes temperature=0.01 error for these models in LLM extraction.

---------

Co-authored-by: rbushria <rbushri@gmail.com>
Co-authored-by: AHMET YILMAZ <tawfik@kidocode.com>
Co-authored-by: Soham Kukreti <kukretisoham@gmail.com>
Co-authored-by: Chris Murphy <chris.murphy@klaviyo.com>
Co-authored-by: unclecode <unclecode@kidocode.com>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
This commit is contained in:
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@@ -20,22 +20,32 @@ Ever wondered why your AI coding assistant struggles with your library despite c
## Latest Release
### [Crawl4AI v0.8.0 Crash Recovery & Prefetch Mode](../blog/release-v0.8.0.md)
*January 2026*
Crawl4AI v0.8.0 introduces crash recovery for deep crawls, a new prefetch mode for fast URL discovery, and critical security fixes for Docker deployments.
Key highlights:
- **🔄 Deep Crawl Crash Recovery**: `on_state_change` callback for real-time state persistence, `resume_state` to continue from checkpoints
- **⚡ Prefetch Mode**: `prefetch=True` for 5-10x faster URL discovery, perfect for two-phase crawling patterns
- **🔒 Security Fixes**: Hooks disabled by default, `file://` URLs blocked on Docker API, `__import__` removed from sandbox
[Read full release notes →](../blog/release-v0.8.0.md)
## Recent Releases
### [Crawl4AI v0.7.8 Stability & Bug Fix Release](../blog/release-v0.7.8.md)
*December 2025*
Crawl4AI v0.7.8 is a focused stability release addressing 11 bugs reported by the community. While there are no new features, these fixes resolve important issues affecting Docker deployments, LLM extraction, URL handling, and dependency compatibility.
Crawl4AI v0.7.8 is a focused stability release addressing 11 bugs reported by the community. Fixes for Docker deployments, LLM extraction, URL handling, and dependency compatibility.
Key highlights:
- **🐳 Docker API Fixes**: ContentRelevanceFilter deserialization, ProxyConfig serialization, cache folder permissions
- **🤖 LLM Improvements**: Configurable rate limiter backoff, HTML input format support, raw HTML URL handling
- **🔗 URL Handling**: Correct relative URL resolution after JavaScript redirects
- **🤖 LLM Improvements**: Configurable rate limiter backoff, HTML input format support
- **📦 Dependencies**: Replaced deprecated PyPDF2 with pypdf, Pydantic v2 ConfigDict compatibility
- **🧠 AdaptiveCrawler**: Fixed query expansion to actually use LLM instead of mock data
[Read full release notes →](../blog/release-v0.7.8.md)
## Recent Releases
### [Crawl4AI v0.7.7 The Self-Hosting & Monitoring Update](../blog/release-v0.7.7.md)
*November 14, 2025*
@@ -52,36 +62,22 @@ Key highlights:
### [Crawl4AI v0.7.6 The Webhook Infrastructure Update](../blog/release-v0.7.6.md)
*October 22, 2025*
Crawl4AI v0.7.6 introduces comprehensive webhook support for the Docker job queue API, bringing real-time notifications to both crawling and LLM extraction workflows. No more polling!
Crawl4AI v0.7.6 introduces comprehensive webhook support for the Docker job queue API, bringing real-time notifications to both crawling and LLM extraction workflows.
Key highlights:
- **🪝 Complete Webhook Support**: Real-time notifications for both `/crawl/job` and `/llm/job` endpoints
- **🔄 Reliable Delivery**: Exponential backoff retry mechanism (5 attempts: 1s → 2s → 4s → 8s → 16s)
- **🔄 Reliable Delivery**: Exponential backoff retry mechanism
- **🔐 Custom Authentication**: Add custom headers for webhook authentication
- **📊 Flexible Delivery**: Choose notification-only or include full data in payload
- **⚙️ Global Configuration**: Set default webhook URL in config.yml for all jobs
[Read full release notes →](../blog/release-v0.7.6.md)
### [Crawl4AI v0.7.5 The Docker Hooks & Security Update](../blog/release-v0.7.5.md)
*September 29, 2025*
Crawl4AI v0.7.5 introduces the powerful Docker Hooks System for complete pipeline customization, enhanced LLM integration with custom providers, HTTPS preservation for modern web security, and resolves multiple community-reported issues.
Key highlights:
- **🔧 Docker Hooks System**: Custom Python functions at 8 key pipeline points for unprecedented customization
- **🤖 Enhanced LLM Integration**: Custom providers with temperature control and base_url configuration
- **🔒 HTTPS Preservation**: Secure internal link handling for modern web applications
- **🐍 Python 3.10+ Support**: Modern language features and enhanced performance
[Read full release notes →](../blog/release-v0.7.5.md)
---
## Older Releases
| Version | Date | Highlights |
|---------|------|------------|
| [v0.7.5](../blog/release-v0.7.5.md) | September 2025 | Docker Hooks System, enhanced LLM integration, HTTPS preservation |
| [v0.7.4](../blog/release-v0.7.4.md) | August 2025 | LLM-powered table extraction, performance improvements |
| [v0.7.3](../blog/release-v0.7.3.md) | July 2025 | Undetected browser, multi-URL config, memory monitoring |
| [v0.7.1](../blog/release-v0.7.1.md) | June 2025 | Bug fixes and stability improvements |

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@@ -0,0 +1,243 @@
# Crawl4AI v0.8.0 Release Notes
**Release Date**: January 2026
**Previous Version**: v0.7.6
**Status**: Release Candidate
---
## Highlights
- **Critical Security Fixes** for Docker API deployment
- **11 New Features** including crash recovery, prefetch mode, and proxy improvements
- **Breaking Changes** - see migration guide below
---
## Breaking Changes
### 1. Docker API: Hooks Disabled by Default
**What changed**: Hooks are now disabled by default on the Docker API.
**Why**: Security fix for Remote Code Execution (RCE) vulnerability.
**Who is affected**: Users of the Docker API who use the `hooks` parameter in `/crawl` requests.
**Migration**:
```bash
# To re-enable hooks (only if you trust all API users):
export CRAWL4AI_HOOKS_ENABLED=true
```
### 2. Docker API: file:// URLs Blocked
**What changed**: The endpoints `/execute_js`, `/screenshot`, `/pdf`, and `/html` now reject `file://` URLs.
**Why**: Security fix for Local File Inclusion (LFI) vulnerability.
**Who is affected**: Users who were reading local files via the Docker API.
**Migration**: Use the Python library directly for local file processing:
```python
# Instead of API call with file:// URL, use library:
from crawl4ai import AsyncWebCrawler
async with AsyncWebCrawler() as crawler:
result = await crawler.arun(url="file:///path/to/file.html")
```
---
## Security Fixes
### Critical: Remote Code Execution via Hooks (CVE Pending)
**Severity**: CRITICAL (CVSS 10.0)
**Affected**: Docker API deployment (all versions before v0.8.0)
**Vector**: `POST /crawl` with malicious `hooks` parameter
**Details**: The `__import__` builtin was available in hook code, allowing attackers to import `os`, `subprocess`, etc. and execute arbitrary commands.
**Fix**:
1. Removed `__import__` from allowed builtins
2. Hooks disabled by default (`CRAWL4AI_HOOKS_ENABLED=false`)
### High: Local File Inclusion via file:// URLs (CVE Pending)
**Severity**: HIGH (CVSS 8.6)
**Affected**: Docker API deployment (all versions before v0.8.0)
**Vector**: `POST /execute_js` (and other endpoints) with `file:///etc/passwd`
**Details**: API endpoints accepted `file://` URLs, allowing attackers to read arbitrary files from the server.
**Fix**: URL scheme validation now only allows `http://`, `https://`, and `raw:` URLs.
### Credits
Discovered by **Neo by ProjectDiscovery** ([projectdiscovery.io](https://projectdiscovery.io)) - December 2025
---
## New Features
### 1. init_scripts Support for BrowserConfig
Pre-page-load JavaScript injection for stealth evasions.
```python
config = BrowserConfig(
init_scripts=[
"Object.defineProperty(navigator, 'webdriver', {get: () => false})"
]
)
```
### 2. CDP Connection Improvements
- WebSocket URL support (`ws://`, `wss://`)
- Proper cleanup with `cdp_cleanup_on_close=True`
- Browser reuse across multiple connections
### 3. Crash Recovery for Deep Crawl Strategies
All deep crawl strategies (BFS, DFS, Best-First) now support crash recovery:
```python
from crawl4ai.deep_crawling import BFSDeepCrawlStrategy
strategy = BFSDeepCrawlStrategy(
max_depth=3,
resume_state=saved_state, # Resume from checkpoint
on_state_change=save_callback # Persist state in real-time
)
```
### 4. PDF and MHTML for raw:/file:// URLs
Generate PDFs and MHTML from cached HTML content.
### 5. Screenshots for raw:/file:// URLs
Render cached HTML and capture screenshots.
### 6. base_url Parameter for CrawlerRunConfig
Proper URL resolution for raw: HTML processing:
```python
config = CrawlerRunConfig(base_url='https://example.com')
result = await crawler.arun(url='raw:{html}', config=config)
```
### 7. Prefetch Mode for Two-Phase Deep Crawling
Fast link extraction without full page processing:
```python
config = CrawlerRunConfig(prefetch=True)
```
### 8. Proxy Rotation and Configuration
Enhanced proxy rotation with sticky sessions support.
### 9. Proxy Support for HTTP Strategy
Non-browser crawler now supports proxies.
### 10. Browser Pipeline for raw:/file:// URLs
New `process_in_browser` parameter for browser operations on local content:
```python
config = CrawlerRunConfig(
process_in_browser=True, # Force browser processing
screenshot=True
)
result = await crawler.arun(url='raw:<html>...</html>', config=config)
```
### 11. Smart TTL Cache for Sitemap URL Seeder
Intelligent cache invalidation for sitemaps:
```python
config = SeedingConfig(
cache_ttl_hours=24,
validate_sitemap_lastmod=True
)
```
---
## Bug Fixes
### raw: URL Parsing Truncates at # Character
**Problem**: CSS color codes like `#eee` were being truncated.
**Before**: `raw:body{background:#eee}``body{background:`
**After**: `raw:body{background:#eee}``body{background:#eee}`
### Caching System Improvements
Various fixes to cache validation and persistence.
---
## Documentation Updates
- Multi-sample schema generation documentation
- URL seeder smart TTL cache parameters
- Security documentation (SECURITY.md)
---
## Upgrade Guide
### From v0.7.x to v0.8.0
1. **Update the package**:
```bash
pip install --upgrade crawl4ai
```
2. **Docker API users**:
- Hooks are now disabled by default
- If you need hooks: `export CRAWL4AI_HOOKS_ENABLED=true`
- `file://` URLs no longer work on API (use library directly)
3. **Review security settings**:
```yaml
# config.yml - recommended for production
security:
enabled: true
jwt_enabled: true
```
4. **Test your integration** before deploying to production
### Breaking Change Checklist
- [ ] Check if you use `hooks` parameter in API calls
- [ ] Check if you use `file://` URLs via the API
- [ ] Update environment variables if needed
- [ ] Review security configuration
---
## Full Changelog
See [CHANGELOG.md](../CHANGELOG.md) for complete version history.
---
## Contributors
Thanks to all contributors who made this release possible.
Special thanks to **Neo by ProjectDiscovery** for responsible security disclosure.
---
*For questions or issues, please open a [GitHub Issue](https://github.com/unclecode/crawl4ai/issues).*

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@@ -4,11 +4,13 @@ One of Crawl4AI's most powerful features is its ability to perform **configurabl
In this tutorial, you'll learn:
1. How to set up a **Basic Deep Crawler** with BFS strategy
2. Understanding the difference between **streamed and non-streamed** output
3. Implementing **filters and scorers** to target specific content
4. Creating **advanced filtering chains** for sophisticated crawls
5. Using **BestFirstCrawling** for intelligent exploration prioritization
1. How to set up a **Basic Deep Crawler** with BFS strategy
2. Understanding the difference between **streamed and non-streamed** output
3. Implementing **filters and scorers** to target specific content
4. Creating **advanced filtering chains** for sophisticated crawls
5. Using **BestFirstCrawling** for intelligent exploration prioritization
6. **Crash recovery** for long-running production crawls
7. **Prefetch mode** for fast URL discovery
> **Prerequisites**
> - Youve completed or read [AsyncWebCrawler Basics](../core/simple-crawling.md) to understand how to run a simple crawl.
@@ -485,7 +487,249 @@ This is especially useful for security-conscious crawling or when dealing with s
---
## 10. Summary & Next Steps
## 10. Crash Recovery for Long-Running Crawls
For production deployments, especially in cloud environments where instances can be terminated unexpectedly, Crawl4AI provides built-in crash recovery support for all deep crawl strategies.
### 10.1 Enabling State Persistence
All deep crawl strategies (BFS, DFS, Best-First) support two optional parameters:
- **`resume_state`**: Pass a previously saved state to resume from a checkpoint
- **`on_state_change`**: Async callback fired after each URL is processed
```python
from crawl4ai.deep_crawling import BFSDeepCrawlStrategy
import json
# Callback to save state after each URL
async def save_state_to_redis(state: dict):
await redis.set("crawl_state", json.dumps(state))
strategy = BFSDeepCrawlStrategy(
max_depth=3,
on_state_change=save_state_to_redis, # Called after each URL
)
```
### 10.2 State Structure
The state dictionary is JSON-serializable and contains:
```python
{
"strategy_type": "bfs", # or "dfs", "best_first"
"visited": ["url1", "url2", ...], # Already crawled URLs
"pending": [{"url": "...", "parent_url": "..."}], # Queue/stack
"depths": {"url1": 0, "url2": 1}, # Depth tracking
"pages_crawled": 42 # Counter
}
```
### 10.3 Resuming from a Checkpoint
```python
import json
from crawl4ai import AsyncWebCrawler, CrawlerRunConfig
from crawl4ai.deep_crawling import BFSDeepCrawlStrategy
# Load saved state (e.g., from Redis, database, or file)
saved_state = json.loads(await redis.get("crawl_state"))
# Resume crawling from where we left off
strategy = BFSDeepCrawlStrategy(
max_depth=3,
resume_state=saved_state, # Continue from checkpoint
on_state_change=save_state_to_redis, # Keep saving progress
)
config = CrawlerRunConfig(deep_crawl_strategy=strategy)
async with AsyncWebCrawler() as crawler:
# Will skip already-visited URLs and continue from pending queue
results = await crawler.arun(start_url, config=config)
```
### 10.4 Manual State Export
You can export the last captured state using `export_state()`. Note that this requires `on_state_change` to be set (state is captured in the callback):
```python
import json
captured_state = None
async def capture_state(state: dict):
global captured_state
captured_state = state
strategy = BFSDeepCrawlStrategy(
max_depth=2,
on_state_change=capture_state, # Required for state capture
)
config = CrawlerRunConfig(deep_crawl_strategy=strategy)
async with AsyncWebCrawler() as crawler:
results = await crawler.arun(start_url, config=config)
# Get the last captured state
state = strategy.export_state()
if state:
# Save to your preferred storage
with open("crawl_checkpoint.json", "w") as f:
json.dump(state, f)
```
### 10.5 Complete Example: Redis-Based Recovery
```python
import asyncio
import json
import redis.asyncio as redis
from crawl4ai import AsyncWebCrawler, CrawlerRunConfig
from crawl4ai.deep_crawling import BFSDeepCrawlStrategy
REDIS_KEY = "crawl4ai:crawl_state"
async def main():
redis_client = redis.Redis(host='localhost', port=6379, db=0)
# Check for existing state
saved_state = None
existing = await redis_client.get(REDIS_KEY)
if existing:
saved_state = json.loads(existing)
print(f"Resuming from checkpoint: {saved_state['pages_crawled']} pages already crawled")
# State persistence callback
async def persist_state(state: dict):
await redis_client.set(REDIS_KEY, json.dumps(state))
# Create strategy with recovery support
strategy = BFSDeepCrawlStrategy(
max_depth=3,
max_pages=100,
resume_state=saved_state,
on_state_change=persist_state,
)
config = CrawlerRunConfig(deep_crawl_strategy=strategy, stream=True)
try:
async with AsyncWebCrawler() as crawler:
async for result in await crawler.arun("https://example.com", config=config):
print(f"Crawled: {result.url}")
except Exception as e:
print(f"Crawl interrupted: {e}")
print("State saved - restart to resume")
finally:
await redis_client.close()
if __name__ == "__main__":
asyncio.run(main())
```
### 10.6 Zero Overhead
When `resume_state=None` and `on_state_change=None` (the defaults), there is no performance impact. State tracking only activates when you enable these features.
---
## 11. Prefetch Mode for Fast URL Discovery
When you need to quickly discover URLs without full page processing, use **prefetch mode**. This is ideal for two-phase crawling where you first map the site, then selectively process specific pages.
### 11.1 Enabling Prefetch Mode
```python
from crawl4ai import AsyncWebCrawler, CrawlerRunConfig
config = CrawlerRunConfig(prefetch=True)
async with AsyncWebCrawler() as crawler:
result = await crawler.arun("https://example.com", config=config)
# Result contains only HTML and links - no markdown, no extraction
print(f"Found {len(result.links['internal'])} internal links")
print(f"Found {len(result.links['external'])} external links")
```
### 11.2 What Gets Skipped
Prefetch mode uses a fast path that bypasses heavy processing:
| Processing Step | Normal Mode | Prefetch Mode |
|----------------|-------------|---------------|
| Fetch HTML | ✅ | ✅ |
| Extract links | ✅ | ✅ (fast `quick_extract_links()`) |
| Generate markdown | ✅ | ❌ Skipped |
| Content scraping | ✅ | ❌ Skipped |
| Media extraction | ✅ | ❌ Skipped |
| LLM extraction | ✅ | ❌ Skipped |
### 11.3 Performance Benefit
- **Normal mode**: Full pipeline (~2-5 seconds per page)
- **Prefetch mode**: HTML + links only (~200-500ms per page)
This makes prefetch mode **5-10x faster** for URL discovery.
### 11.4 Two-Phase Crawling Pattern
The most common use case is two-phase crawling:
```python
import asyncio
from crawl4ai import AsyncWebCrawler, CrawlerRunConfig
async def two_phase_crawl(start_url: str):
async with AsyncWebCrawler() as crawler:
# ═══════════════════════════════════════════════
# Phase 1: Fast discovery (prefetch mode)
# ═══════════════════════════════════════════════
prefetch_config = CrawlerRunConfig(prefetch=True)
discovery = await crawler.arun(start_url, config=prefetch_config)
all_urls = [link["href"] for link in discovery.links.get("internal", [])]
print(f"Discovered {len(all_urls)} URLs")
# Filter to URLs you care about
blog_urls = [url for url in all_urls if "/blog/" in url]
print(f"Found {len(blog_urls)} blog posts to process")
# ═══════════════════════════════════════════════
# Phase 2: Full processing on selected URLs only
# ═══════════════════════════════════════════════
full_config = CrawlerRunConfig(
# Your normal extraction settings
word_count_threshold=100,
remove_overlay_elements=True,
)
results = []
for url in blog_urls:
result = await crawler.arun(url, config=full_config)
if result.success:
results.append(result)
print(f"Processed: {url}")
return results
if __name__ == "__main__":
results = asyncio.run(two_phase_crawl("https://example.com"))
print(f"Fully processed {len(results)} pages")
```
### 11.5 Use Cases
- **Site mapping**: Quickly discover all URLs before deciding what to process
- **Link validation**: Check which pages exist without heavy processing
- **Selective deep crawl**: Prefetch to find URLs, filter by pattern, then full crawl
- **Crawl planning**: Estimate crawl size before committing resources
---
## 12. Summary & Next Steps
In this **Deep Crawling with Crawl4AI** tutorial, you learned to:
@@ -495,5 +739,7 @@ In this **Deep Crawling with Crawl4AI** tutorial, you learned to:
- Use scorers to prioritize the most relevant pages
- Limit crawls with `max_pages` and `score_threshold` parameters
- Build a complete advanced crawler with combined techniques
- **Implement crash recovery** with `resume_state` and `on_state_change` for production deployments
- **Use prefetch mode** for fast URL discovery and two-phase crawling
With these tools, you can efficiently extract structured data from websites at scale, focusing precisely on the content you need for your specific use case.

View File

@@ -67,13 +67,13 @@ Pull and run images directly from Docker Hub without building locally.
#### 1. Pull the Image
Our latest release is `0.7.6`. Images are built with multi-arch manifests, so Docker automatically pulls the correct version for your system.
Our latest release is `0.8.0`. Images are built with multi-arch manifests, so Docker automatically pulls the correct version for your system.
> 💡 **Note**: The `latest` tag points to the stable `0.7.6` version.
> 💡 **Note**: The `latest` tag points to the stable `0.8.0` version.
```bash
# Pull the latest version
docker pull unclecode/crawl4ai:0.7.6
docker pull unclecode/crawl4ai:0.8.0
# Or pull using the latest tag
docker pull unclecode/crawl4ai:latest
@@ -145,7 +145,7 @@ docker stop crawl4ai && docker rm crawl4ai
#### Docker Hub Versioning Explained
* **Image Name:** `unclecode/crawl4ai`
* **Tag Format:** `LIBRARY_VERSION[-SUFFIX]` (e.g., `0.7.6`)
* **Tag Format:** `LIBRARY_VERSION[-SUFFIX]` (e.g., `0.8.0`)
* `LIBRARY_VERSION`: The semantic version of the core `crawl4ai` Python library
* `SUFFIX`: Optional tag for release candidates (``) and revisions (`r1`)
* **`latest` Tag:** Points to the most recent stable version

View File

@@ -255,6 +255,8 @@ The `SeedingConfig` object is your control panel. Here's everything you can conf
| `scoring_method` | str | None | Scoring method (currently "bm25") |
| `score_threshold` | float | None | Minimum score to include URL |
| `filter_nonsense_urls` | bool | True | Filter out utility URLs (robots.txt, etc.) |
| `cache_ttl_hours` | int | 24 | Hours before sitemap cache expires (0 = no TTL) |
| `validate_sitemap_lastmod` | bool | True | Check sitemap's lastmod and refetch if newer |
#### Pattern Matching Examples
@@ -968,10 +970,49 @@ config = SeedingConfig(
The seeder automatically caches results to speed up repeated operations:
- **Common Crawl cache**: `~/.crawl4ai/seeder_cache/[index]_[domain]_[hash].jsonl`
- **Sitemap cache**: `~/.crawl4ai/seeder_cache/sitemap_[domain]_[hash].jsonl`
- **Sitemap cache**: `~/.crawl4ai/seeder_cache/sitemap_[domain]_[hash].json`
- **HEAD data cache**: `~/.cache/url_seeder/head/[hash].json`
Cache expires after 7 days by default. Use `force=True` to refresh.
#### Smart TTL Cache for Sitemaps
Sitemap caches now include intelligent validation:
```python
# Default: 24-hour TTL with lastmod validation
config = SeedingConfig(
source="sitemap",
cache_ttl_hours=24, # Cache expires after 24 hours
validate_sitemap_lastmod=True # Also check if sitemap was updated
)
# Aggressive caching (1 week, no lastmod check)
config = SeedingConfig(
source="sitemap",
cache_ttl_hours=168, # 7 days
validate_sitemap_lastmod=False # Trust TTL only
)
# Always validate (no TTL, only lastmod)
config = SeedingConfig(
source="sitemap",
cache_ttl_hours=0, # Disable TTL
validate_sitemap_lastmod=True # Refetch if sitemap has newer lastmod
)
# Always fresh (bypass cache completely)
config = SeedingConfig(
source="sitemap",
force=True # Ignore all caching
)
```
**Cache validation priority:**
1. `force=True` → Always refetch
2. Cache doesn't exist → Fetch fresh
3. `validate_sitemap_lastmod=True` and sitemap has newer `<lastmod>` → Refetch
4. `cache_ttl_hours > 0` and cache is older than TTL → Refetch
5. Cache corrupted → Refetch (automatic recovery)
6. Otherwise → Use cache
### Pattern Matching Strategies
@@ -1060,6 +1101,9 @@ config = SeedingConfig(
| Rate limit errors | Reduce `hits_per_sec` and `concurrency` |
| Memory issues with large sites | Use `max_urls` to limit results, reduce `concurrency` |
| Connection not closed | Use context manager or call `await seeder.close()` |
| Stale/outdated URLs | Set `cache_ttl_hours=0` or use `force=True` |
| Cache not updating | Check `validate_sitemap_lastmod=True`, or use `force=True` |
| Incomplete URL list | Delete cache file and refetch, or use `force=True` |
### Performance Benchmarks
@@ -1119,6 +1163,7 @@ config = SeedingConfig(
3. **Context Manager Support**: Automatic cleanup with `async with` statement
4. **URL-Based Scoring**: Smart filtering even without head extraction
5. **Smart URL Filtering**: Automatically excludes utility/nonsense URLs
6. **Dual Caching**: Separate caches for URL lists and metadata
6. **Smart TTL Cache**: Sitemap caches with TTL expiry and lastmod validation
7. **Automatic Cache Recovery**: Corrupted or incomplete caches are automatically refreshed
Now go forth and seed intelligently! 🌱🚀
Now go forth and seed intelligently!

View File

@@ -712,10 +712,106 @@ strategy = JsonCssExtractionStrategy(css_schema)
3. **Consider Both CSS and XPath**: Try both schema types and choose the one that works best for your specific case.
4. **Cache Generated Schemas**: Since generation uses LLM, save successful schemas for reuse.
5. **API Token Security**: Never hardcode API tokens. Use environment variables or secure configuration management.
6. **Choose Provider Wisely**:
6. **Choose Provider Wisely**:
- Use OpenAI for production-quality schemas
- Use Ollama for development, testing, or when you need a self-hosted solution
### Multi-Sample Schema Generation
When scraping multiple pages with varying DOM structures (e.g., product pages where table rows appear in different positions), single-sample schema generation may produce **fragile selectors** like `tr:nth-child(6)` that break on other pages.
**The Problem:**
```
Page A: Manufacturer is in row 6 → selector: tr:nth-child(6) td a
Page B: Manufacturer is in row 5 → selector FAILS
Page C: Manufacturer is in row 7 → selector FAILS
```
**The Solution:** Provide multiple HTML samples so the LLM identifies stable patterns that work across all pages.
```python
from crawl4ai import JsonCssExtractionStrategy, LLMConfig
# Collect HTML samples from different pages
html_sample_1 = """
<table class="specs">
<tr><td>Brand</td><td>Apple</td></tr>
<tr><td>Manufacturer</td><td><a href="/m/apple">Apple Inc</a></td></tr>
</table>
"""
html_sample_2 = """
<table class="specs">
<tr><td>Manufacturer</td><td><a href="/m/samsung">Samsung</a></td></tr>
<tr><td>Brand</td><td>Galaxy</td></tr>
</table>
"""
html_sample_3 = """
<table class="specs">
<tr><td>Model</td><td>Pixel 8</td></tr>
<tr><td>Brand</td><td>Google</td></tr>
<tr><td>Manufacturer</td><td><a href="/m/google">Google LLC</a></td></tr>
</table>
"""
# Combine samples with labels
combined_html = """
## HTML Sample 1 (Product A):
```html
""" + html_sample_1 + """
```
## HTML Sample 2 (Product B):
```html
""" + html_sample_2 + """
```
## HTML Sample 3 (Product C):
```html
""" + html_sample_3 + """
```
"""
# Provide instructions for stable selectors
query = """
IMPORTANT: I'm providing 3 HTML samples from different product pages.
The manufacturer field appears in different row positions across pages.
Generate selectors using stable attributes like href patterns (e.g., a[href*='/m/'])
instead of fragile positional selectors like nth-child().
Extract: manufacturer name and link.
"""
# Generate schema with multi-sample awareness
schema = JsonCssExtractionStrategy.generate_schema(
html=combined_html,
query=query,
schema_type="CSS",
llm_config=LLMConfig(provider="openai/gpt-4o", api_token="your-token")
)
# The generated schema will use stable selectors like:
# a[href*="/m/"] instead of tr:nth-child(6) td a
print(schema)
```
**Key Points for Multi-Sample Queries:**
1. **Format samples clearly** - Use markdown headers and code blocks to separate samples
2. **State the number of samples** - "I'm providing 3 HTML samples..."
3. **Explain the variation** - "...the manufacturer field appears in different row positions"
4. **Request stable selectors** - "Use href patterns, data attributes, or class names instead of nth-child"
**Stable vs Fragile Selectors:**
| Fragile (single sample) | Stable (multi-sample) |
|------------------------|----------------------|
| `tr:nth-child(6) td a` | `a[href*="/m/"]` |
| `div:nth-child(3) .price` | `.price, [data-price]` |
| `ul li:first-child` | `li[data-featured="true"]` |
This approach lets you generate schemas once that work reliably across hundreds of similar pages with varying structures.
---
## 10. Conclusion