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### Session Management
Session management in Crawl4AI is a powerful feature that allows you to maintain state across multiple requests, making it particularly suitable for handling complex multi-step crawling tasks. It enables you to reuse the same browser tab (or page object) across sequential actions and crawls, which is beneficial for:
- **Performing JavaScript actions before and after crawling.**
- **Executing multiple sequential crawls faster** without needing to reopen tabs or allocate memory repeatedly.
**Note:** This feature is designed for sequential workflows and is not suitable for parallel operations.
---
#### Basic Session Usage
Use `BrowserConfig` and `CrawlerRunConfig` to maintain state with a `session_id`:
```python
from crawl4ai.async_configs import BrowserConfig, CrawlerRunConfig
async with AsyncWebCrawler() as crawler:
session_id = "my_session"
# Define configurations
config1 = CrawlerRunConfig(url="https://example.com/page1", session_id=session_id)
config2 = CrawlerRunConfig(url="https://example.com/page2", session_id=session_id)
# First request
result1 = await crawler.arun(config=config1)
# Subsequent request using the same session
result2 = await crawler.arun(config=config2)
# Clean up when done
await crawler.crawler_strategy.kill_session(session_id)
```
---
#### Dynamic Content with Sessions
Here's an example of crawling GitHub commits across multiple pages while preserving session state:
```python
from crawl4ai.async_configs import CrawlerRunConfig
from crawl4ai.extraction_strategy import JsonCssExtractionStrategy
from crawl4ai.cache_context import CacheMode
async def crawl_dynamic_content():
async with AsyncWebCrawler() as crawler:
session_id = "github_commits_session"
url = "https://github.com/microsoft/TypeScript/commits/main"
all_commits = []
# Define extraction schema
schema = {
"name": "Commit Extractor",
"baseSelector": "li.Box-sc-g0xbh4-0",
"fields": [{"name": "title", "selector": "h4.markdown-title", "type": "text"}],
}
extraction_strategy = JsonCssExtractionStrategy(schema)
# JavaScript and wait configurations
js_next_page = """document.querySelector('a[data-testid="pagination-next-button"]').click();"""
wait_for = """() => document.querySelectorAll('li.Box-sc-g0xbh4-0').length > 0"""
# Crawl multiple pages
for page in range(3):
config = CrawlerRunConfig(
url=url,
session_id=session_id,
extraction_strategy=extraction_strategy,
js_code=js_next_page if page > 0 else None,
wait_for=wait_for if page > 0 else None,
js_only=page > 0,
cache_mode=CacheMode.BYPASS
)
result = await crawler.arun(config=config)
if result.success:
commits = json.loads(result.extracted_content)
all_commits.extend(commits)
print(f"Page {page + 1}: Found {len(commits)} commits")
# Clean up session
await crawler.crawler_strategy.kill_session(session_id)
return all_commits
```
---
#### Session Best Practices
1. **Descriptive Session IDs**:
Use meaningful names for session IDs to organize workflows:
```python
session_id = "login_flow_session"
session_id = "product_catalog_session"
```
2. **Resource Management**:
Always ensure sessions are cleaned up to free resources:
```python
try:
# Your crawling code here
pass
finally:
await crawler.crawler_strategy.kill_session(session_id)
```
3. **State Maintenance**:
Reuse the session for subsequent actions within the same workflow:
```python
# Step 1: Login
login_config = CrawlerRunConfig(
url="https://example.com/login",
session_id=session_id,
js_code="document.querySelector('form').submit();"
)
await crawler.arun(config=login_config)
# Step 2: Verify login success
dashboard_config = CrawlerRunConfig(
url="https://example.com/dashboard",
session_id=session_id,
wait_for="css:.user-profile" # Wait for authenticated content
)
result = await crawler.arun(config=dashboard_config)
```
---
#### Common Use Cases for Sessions
1. **Authentication Flows**: Login and interact with secured pages.
2. **Pagination Handling**: Navigate through multiple pages.
3. **Form Submissions**: Fill forms, submit, and process results.
4. **Multi-step Processes**: Complete workflows that span multiple actions.
5. **Dynamic Content Navigation**: Handle JavaScript-rendered or event-triggered content.
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