import socket
import aiohttp
import asyncio
import urllib.parse
import validators
from typing import Any, AsyncIterator, Dict, Iterator, List, Sequence, Union
from langchain_community.document_loaders import (
WebBaseLoader,
)
from langchain_core.documents import Document
from open_webui.constants import ERROR_MESSAGES
from open_webui.config import ENABLE_RAG_LOCAL_WEB_FETCH
from open_webui.env import SRC_LOG_LEVELS
import logging
log = logging.getLogger(__name__)
log.setLevel(SRC_LOG_LEVELS["RAG"])
def validate_url(url: Union[str, Sequence[str]]):
if isinstance(url, str):
if isinstance(validators.url(url), validators.ValidationError):
raise ValueError(ERROR_MESSAGES.INVALID_URL)
if not ENABLE_RAG_LOCAL_WEB_FETCH:
# Local web fetch is disabled, filter out any URLs that resolve to private IP addresses
parsed_url = urllib.parse.urlparse(url)
# Get IPv4 and IPv6 addresses
ipv4_addresses, ipv6_addresses = resolve_hostname(parsed_url.hostname)
# Check if any of the resolved addresses are private
# This is technically still vulnerable to DNS rebinding attacks, as we don't control WebBaseLoader
for ip in ipv4_addresses:
if validators.ipv4(ip, private=True):
raise ValueError(ERROR_MESSAGES.INVALID_URL)
for ip in ipv6_addresses:
if validators.ipv6(ip, private=True):
raise ValueError(ERROR_MESSAGES.INVALID_URL)
return True
elif isinstance(url, Sequence):
return all(validate_url(u) for u in url)
else:
return False
def safe_validate_urls(url: Sequence[str]) -> Sequence[str]:
valid_urls = []
for u in url:
try:
if validate_url(u):
valid_urls.append(u)
except ValueError:
continue
return valid_urls
def resolve_hostname(hostname):
# Get address information
addr_info = socket.getaddrinfo(hostname, None)
# Extract IP addresses from address information
ipv4_addresses = [info[4][0] for info in addr_info if info[0] == socket.AF_INET]
ipv6_addresses = [info[4][0] for info in addr_info if info[0] == socket.AF_INET6]
return ipv4_addresses, ipv6_addresses
class SafeWebBaseLoader(WebBaseLoader):
"""WebBaseLoader with enhanced error handling for URLs."""
def __init__(self, trust_env: bool = False, *args, **kwargs):
"""Initialize SafeWebBaseLoader
Args:
trust_env (bool, optional): set to True if using proxy to make web requests, for example
using http(s)_proxy environment variables. Defaults to False.
"""
super().__init__(*args, **kwargs)
self.trust_env = trust_env
async def _fetch(
self, url: str, retries: int = 3, cooldown: int = 2, backoff: float = 1.5
) -> str:
async with aiohttp.ClientSession(trust_env=self.trust_env) as session:
for i in range(retries):
try:
kwargs: Dict = dict(
headers=self.session.headers,
cookies=self.session.cookies.get_dict(),
)
if not self.session.verify:
kwargs["ssl"] = False
async with session.get(
url, **(self.requests_kwargs | kwargs)
) as response:
if self.raise_for_status:
response.raise_for_status()
return await response.text()
except aiohttp.ClientConnectionError as e:
if i == retries - 1:
raise
else:
log.warning(
f"Error fetching {url} with attempt "
f"{i + 1}/{retries}: {e}. Retrying..."
)
await asyncio.sleep(cooldown * backoff**i)
raise ValueError("retry count exceeded")
def _unpack_fetch_results(
self, results: Any, urls: List[str], parser: Union[str, None] = None
) -> List[Any]:
"""Unpack fetch results into BeautifulSoup objects."""
from bs4 import BeautifulSoup
final_results = []
for i, result in enumerate(results):
url = urls[i]
if parser is None:
if url.endswith(".xml"):
parser = "xml"
else:
parser = self.default_parser
self._check_parser(parser)
final_results.append(BeautifulSoup(result, parser, **self.bs_kwargs))
return final_results
async def ascrape_all(
self, urls: List[str], parser: Union[str, None] = None
) -> List[Any]:
"""Async fetch all urls, then return soups for all results."""
results = await self.fetch_all(urls)
return self._unpack_fetch_results(results, urls, parser=parser)
def lazy_load(self) -> Iterator[Document]:
"""Lazy load text from the url(s) in web_path with error handling."""
for path in self.web_paths:
try:
soup = self._scrape(path, bs_kwargs=self.bs_kwargs)
text = soup.get_text(**self.bs_get_text_kwargs)
# Build metadata
metadata = {"source": path}
if title := soup.find("title"):
metadata["title"] = title.get_text()
if description := soup.find("meta", attrs={"name": "description"}):
metadata["description"] = description.get(
"content", "No description found."
)
if html := soup.find("html"):
metadata["language"] = html.get("lang", "No language found.")
yield Document(page_content=text, metadata=metadata)
except Exception as e:
# Log the error and continue with the next URL
log.error(f"Error loading {path}: {e}")
async def alazy_load(self) -> AsyncIterator[Document]:
"""Async lazy load text from the url(s) in web_path."""
results = await self.ascrape_all(self.web_paths)
for path, soup in zip(self.web_paths, results):
text = soup.get_text(**self.bs_get_text_kwargs)
metadata = {"source": path}
if title := soup.find("title"):
metadata["title"] = title.get_text()
if description := soup.find("meta", attrs={"name": "description"}):
metadata["description"] = description.get(
"content", "No description found."
)
if html := soup.find("html"):
metadata["language"] = html.get("lang", "No language found.")
yield Document(page_content=text, metadata=metadata)
async def aload(self) -> list[Document]:
"""Load data into Document objects."""
return [document async for document in self.alazy_load()]
def get_web_loader(
urls: Union[str, Sequence[str]],
verify_ssl: bool = True,
requests_per_second: int = 2,
trust_env: bool = False,
):
# Check if the URLs are valid
safe_urls = safe_validate_urls([urls] if isinstance(urls, str) else urls)
return SafeWebBaseLoader(
web_path=safe_urls,
verify_ssl=verify_ssl,
requests_per_second=requests_per_second,
continue_on_failure=True,
trust_env=trust_env,
)