fix: Correct URL matcher fallback behavior and improve memory monitoring

Fix critical issue where unmatched URLs incorrectly used the first config instead of failing safely. Also clarify that configs without url_matcher match ALL URLs by design, and improve memory usage monitoring.

Bug fixes:
- Change select_config() to return None when no config matches instead of using first config
- Add proper error handling in dispatchers when no config matches a URL
- Return failed CrawlResult with "No matching configuration found" error message
- Fix is_match() to return True when url_matcher is None (matches all URLs)
- Import and use get_true_memory_usage_percent() for more accurate memory monitoring

Behavior clarification:
- CrawlerRunConfig with url_matcher=None matches ALL URLs (not nothing)
- This is the intended behavior for default/fallback configurations
- Enables clean pattern: specific configs first, default config last

Documentation updates:
- Clarify that configs without url_matcher match everything
- Explain "No matching configuration found" error when no default config
- Add examples showing proper default config usage
- Update all relevant docs: multi-url-crawling.md, arun_many.md, parameters.md
- Simplify API config examples by removing extraction_strategy

Demo and test updates:
- Update demo_multi_config_clean.py with commented default config to show behavior
- Change example URL to w3schools.com to demonstrate no-match scenario
- Uncomment all test URLs in test_multi_config.py for comprehensive testing

Breaking changes: None - this restores the intended behavior

This ensures URLs only get processed with appropriate configs, preventing
issues like HTML pages being processed with PDF extraction strategies.
This commit is contained in:
ntohidi
2025-08-03 16:50:54 +08:00
parent a03e68fa2f
commit 307fe28b32
9 changed files with 251 additions and 29 deletions

View File

@@ -1343,10 +1343,10 @@ class CrawlerRunConfig():
url: The URL to check against this config's matcher
Returns:
bool: True if this config should be used for the URL
bool: True if this config should be used for the URL or if no matcher is set.
"""
if self.url_matcher is None:
return False
return True
if callable(self.url_matcher):
# Single function matcher

View File

@@ -22,6 +22,8 @@ from urllib.parse import urlparse
import random
from abc import ABC, abstractmethod
from .memory_utils import get_true_memory_usage_percent
class RateLimiter:
def __init__(
@@ -96,7 +98,7 @@ class BaseDispatcher(ABC):
self.rate_limiter = rate_limiter
self.monitor = monitor
def select_config(self, url: str, configs: Union[CrawlerRunConfig, List[CrawlerRunConfig]]) -> CrawlerRunConfig:
def select_config(self, url: str, configs: Union[CrawlerRunConfig, List[CrawlerRunConfig]]) -> Optional[CrawlerRunConfig]:
"""Select the appropriate config for a given URL.
Args:
@@ -104,23 +106,23 @@ class BaseDispatcher(ABC):
configs: Single config or list of configs to choose from
Returns:
The matching config, or the first config if no match, or a default config if empty list
The matching config, or None if no match found
"""
# Single config - return as is
if isinstance(configs, CrawlerRunConfig):
return configs
# Empty list - return default config
# Empty list - return None
if not configs:
return CrawlerRunConfig()
return None
# Find first matching config
for config in configs:
if config.is_match(url):
return config
# No match found - return first config as fallback
return configs[0]
# No match found - return None to indicate URL should be skipped
return None
@abstractmethod
async def crawl_url(
@@ -173,7 +175,7 @@ class MemoryAdaptiveDispatcher(BaseDispatcher):
async def _memory_monitor_task(self):
"""Background task to continuously monitor memory usage and update state"""
while True:
self.current_memory_percent = psutil.virtual_memory().percent
self.current_memory_percent = get_true_memory_usage_percent()
# Enter memory pressure mode if we cross the threshold
if self.current_memory_percent >= self.memory_threshold_percent:
@@ -237,6 +239,34 @@ class MemoryAdaptiveDispatcher(BaseDispatcher):
# Select appropriate config for this URL
selected_config = self.select_config(url, config)
# If no config matches, return failed result
if selected_config is None:
error_message = f"No matching configuration found for URL: {url}"
if self.monitor:
self.monitor.update_task(
task_id,
status=CrawlStatus.FAILED,
error_message=error_message
)
return CrawlerTaskResult(
task_id=task_id,
url=url,
result=CrawlResult(
url=url,
html="",
metadata={"status": "no_config_match"},
success=False,
error_message=error_message
),
memory_usage=0,
peak_memory=0,
start_time=start_time,
end_time=time.time(),
error_message=error_message,
retry_count=retry_count
)
# Get starting memory for accurate measurement
process = psutil.Process()
start_memory = process.memory_info().rss / (1024 * 1024)
@@ -611,6 +641,33 @@ class SemaphoreDispatcher(BaseDispatcher):
# Select appropriate config for this URL
selected_config = self.select_config(url, config)
# If no config matches, return failed result
if selected_config is None:
error_message = f"No matching configuration found for URL: {url}"
if self.monitor:
self.monitor.update_task(
task_id,
status=CrawlStatus.FAILED,
error_message=error_message
)
return CrawlerTaskResult(
task_id=task_id,
url=url,
result=CrawlResult(
url=url,
html="",
metadata={"status": "no_config_match"},
success=False,
error_message=error_message
),
memory_usage=0,
peak_memory=0,
start_time=start_time,
end_time=time.time(),
error_message=error_message
)
try:
if self.monitor:

79
crawl4ai/memory_utils.py Normal file
View File

@@ -0,0 +1,79 @@
import psutil
import platform
import subprocess
from typing import Tuple
def get_true_available_memory_gb() -> float:
"""Get truly available memory including inactive pages (cross-platform)"""
vm = psutil.virtual_memory()
if platform.system() == 'Darwin': # macOS
# On macOS, we need to include inactive memory too
try:
# Use vm_stat to get accurate values
result = subprocess.run(['vm_stat'], capture_output=True, text=True)
lines = result.stdout.split('\n')
page_size = 16384 # macOS page size
pages = {}
for line in lines:
if 'Pages free:' in line:
pages['free'] = int(line.split()[-1].rstrip('.'))
elif 'Pages inactive:' in line:
pages['inactive'] = int(line.split()[-1].rstrip('.'))
elif 'Pages speculative:' in line:
pages['speculative'] = int(line.split()[-1].rstrip('.'))
elif 'Pages purgeable:' in line:
pages['purgeable'] = int(line.split()[-1].rstrip('.'))
# Calculate total available (free + inactive + speculative + purgeable)
total_available_pages = (
pages.get('free', 0) +
pages.get('inactive', 0) +
pages.get('speculative', 0) +
pages.get('purgeable', 0)
)
available_gb = (total_available_pages * page_size) / (1024**3)
return available_gb
except:
# Fallback to psutil
return vm.available / (1024**3)
else:
# For Windows and Linux, psutil.available is accurate
return vm.available / (1024**3)
def get_true_memory_usage_percent() -> float:
"""
Get memory usage percentage that accounts for platform differences.
Returns:
float: Memory usage percentage (0-100)
"""
vm = psutil.virtual_memory()
total_gb = vm.total / (1024**3)
available_gb = get_true_available_memory_gb()
# Calculate used percentage based on truly available memory
used_percent = 100.0 * (total_gb - available_gb) / total_gb
# Ensure it's within valid range
return max(0.0, min(100.0, used_percent))
def get_memory_stats() -> Tuple[float, float, float]:
"""
Get comprehensive memory statistics.
Returns:
Tuple[float, float, float]: (used_percent, available_gb, total_gb)
"""
vm = psutil.virtual_memory()
total_gb = vm.total / (1024**3)
available_gb = get_true_available_memory_gb()
used_percent = get_true_memory_usage_percent()
return used_percent, available_gb, total_gb