Files
crawl4ai/docs/md_v2/api/adaptive-crawler.md
UncleCode 1a73fb60db feat(crawl4ai): Implement adaptive crawling feature
This commit introduces the adaptive crawling feature to the crawl4ai project. The adaptive crawling feature intelligently determines when sufficient information has been gathered during a crawl, improving efficiency and reducing unnecessary resource usage.

The changes include the addition of new files related to the adaptive crawler, modifications to the existing files, and updates to the documentation. The new files include the main adaptive crawler script, utility functions, and various configuration and strategy scripts. The existing files that were modified include the project's initialization file and utility functions. The documentation has been updated to include detailed explanations and examples of the adaptive crawling feature.

The adaptive crawling feature will significantly enhance the capabilities of the crawl4ai project, providing users with a more efficient and intelligent web crawling tool.

Significant modifications:
- Added adaptive_crawler.py and related scripts
- Modified __init__.py and utils.py
- Updated documentation with details about the adaptive crawling feature
- Added tests for the new feature

BREAKING CHANGE: This is a significant feature addition that may affect the overall behavior of the crawl4ai project. Users are advised to review the updated documentation to understand how to use the new feature.

Refs: #123, #456
2025-07-04 15:16:53 +08:00

244 lines
5.4 KiB
Markdown

# AdaptiveCrawler
The `AdaptiveCrawler` class implements intelligent web crawling that automatically determines when sufficient information has been gathered to answer a query. It uses a three-layer scoring system to evaluate coverage, consistency, and saturation.
## Constructor
```python
AdaptiveCrawler(
crawler: AsyncWebCrawler,
config: Optional[AdaptiveConfig] = None
)
```
### Parameters
- **crawler** (`AsyncWebCrawler`): The underlying web crawler instance to use for fetching pages
- **config** (`Optional[AdaptiveConfig]`): Configuration settings for adaptive crawling behavior. If not provided, uses default settings.
## Primary Method
### digest()
The main method that performs adaptive crawling starting from a URL with a specific query.
```python
async def digest(
start_url: str,
query: str,
resume_from: Optional[Union[str, Path]] = None
) -> CrawlState
```
#### Parameters
- **start_url** (`str`): The starting URL for crawling
- **query** (`str`): The search query that guides the crawling process
- **resume_from** (`Optional[Union[str, Path]]`): Path to a saved state file to resume from
#### Returns
- **CrawlState**: The final crawl state containing all crawled URLs, knowledge base, and metrics
#### Example
```python
async with AsyncWebCrawler() as crawler:
adaptive = AdaptiveCrawler(crawler)
state = await adaptive.digest(
start_url="https://docs.python.org",
query="async context managers"
)
```
## Properties
### confidence
Current confidence score (0-1) indicating information sufficiency.
```python
@property
def confidence(self) -> float
```
### coverage_stats
Dictionary containing detailed coverage statistics.
```python
@property
def coverage_stats(self) -> Dict[str, float]
```
Returns:
- **coverage**: Query term coverage score
- **consistency**: Information consistency score
- **saturation**: Content saturation score
- **confidence**: Overall confidence score
### is_sufficient
Boolean indicating whether sufficient information has been gathered.
```python
@property
def is_sufficient(self) -> bool
```
### state
Access to the current crawl state.
```python
@property
def state(self) -> CrawlState
```
## Methods
### get_relevant_content()
Retrieve the most relevant content from the knowledge base.
```python
def get_relevant_content(
self,
top_k: int = 5
) -> List[Dict[str, Any]]
```
#### Parameters
- **top_k** (`int`): Number of top relevant documents to return (default: 5)
#### Returns
List of dictionaries containing:
- **url**: The URL of the page
- **content**: The page content
- **score**: Relevance score
- **metadata**: Additional page metadata
### print_stats()
Display crawl statistics in formatted output.
```python
def print_stats(
self,
detailed: bool = False
) -> None
```
#### Parameters
- **detailed** (`bool`): If True, shows detailed metrics with colors. If False, shows summary table.
### export_knowledge_base()
Export the collected knowledge base to a JSONL file.
```python
def export_knowledge_base(
self,
path: Union[str, Path]
) -> None
```
#### Parameters
- **path** (`Union[str, Path]`): Output file path for JSONL export
#### Example
```python
adaptive.export_knowledge_base("my_knowledge.jsonl")
```
### import_knowledge_base()
Import a previously exported knowledge base.
```python
def import_knowledge_base(
self,
path: Union[str, Path]
) -> None
```
#### Parameters
- **path** (`Union[str, Path]`): Path to JSONL file to import
## Configuration
The `AdaptiveConfig` class controls the behavior of adaptive crawling:
```python
@dataclass
class AdaptiveConfig:
confidence_threshold: float = 0.8 # Stop when confidence reaches this
max_pages: int = 50 # Maximum pages to crawl
top_k_links: int = 5 # Links to follow per page
min_gain_threshold: float = 0.1 # Minimum expected gain to continue
save_state: bool = False # Auto-save crawl state
state_path: Optional[str] = None # Path for state persistence
```
### Example with Custom Config
```python
config = AdaptiveConfig(
confidence_threshold=0.7,
max_pages=20,
top_k_links=3
)
adaptive = AdaptiveCrawler(crawler, config=config)
```
## Complete Example
```python
import asyncio
from crawl4ai import AsyncWebCrawler, AdaptiveCrawler, AdaptiveConfig
async def main():
# Configure adaptive crawling
config = AdaptiveConfig(
confidence_threshold=0.75,
max_pages=15,
save_state=True,
state_path="my_crawl.json"
)
async with AsyncWebCrawler() as crawler:
adaptive = AdaptiveCrawler(crawler, config)
# Start crawling
state = await adaptive.digest(
start_url="https://example.com/docs",
query="authentication oauth2 jwt"
)
# Check results
print(f"Confidence achieved: {adaptive.confidence:.0%}")
adaptive.print_stats()
# Get most relevant pages
for page in adaptive.get_relevant_content(top_k=3):
print(f"- {page['url']} (score: {page['score']:.2f})")
# Export for later use
adaptive.export_knowledge_base("auth_knowledge.jsonl")
if __name__ == "__main__":
asyncio.run(main())
```
## See Also
- [digest() Method Reference](digest.md)
- [Adaptive Crawling Guide](../core/adaptive-crawling.md)
- [Advanced Adaptive Strategies](../advanced/adaptive-strategies.md)