Sitemap
Extends from the WebBaseLoader
, SitemapLoader
loads a sitemap from a given URL, and then scrape and load all pages in the sitemap, returning each page as a Document.
The scraping is done concurrently. There are reasonable limits to concurrent requests, defaulting to 2 per second. If you aren't concerned about being a good citizen, or you control the scrapped server, or don't care about load. Note, while this will speed up the scraping process, but it may cause the server to block you. Be careful!
%pip install --upgrade --quiet nest_asyncio
# fixes a bug with asyncio and jupyter
import nest_asyncio
nest_asyncio.apply()
from langchain_community.document_loaders.sitemap import SitemapLoader
sitemap_loader = SitemapLoader(web_path="https://api.python.langchain.com/sitemap.xml")
docs = sitemap_loader.load()
You can change the requests_per_second
parameter to increase the max concurrent requests. and use requests_kwargs
to pass kwargs when send requests.
sitemap_loader.requests_per_second = 2
# Optional: avoid `[SSL: CERTIFICATE_VERIFY_FAILED]` issue
sitemap_loader.requests_kwargs = {"verify": False}
docs[0]
Document(page_content='\n\n\n\n\n\n\n\n\n\nLangChain Python API Reference Documentation.\n\n\nYou will be automatically redirected to the new location of this page.\n\n', metadata={'source': 'https://api.python.langchain.com/en/stable/', 'loc': 'https://api.python.langchain.com/en/stable/', 'lastmod': '2024-02-09T01:10:49.422114+00:00', 'changefreq': 'weekly', 'priority': '1'})
Filtering sitemap URLs
Sitemaps can be massive files, with thousands of URLs. Often you don't need every single one of them. You can filter the URLs by passing a list of strings or regex patterns to the filter_urls
parameter. Only URLs that match one of the patterns will be loaded.
loader = SitemapLoader(
web_path="https://api.python.langchain.com/sitemap.xml",
filter_urls=["https://api.python.langchain.com/en/latest"],
)
documents = loader.load()
documents[0]
Document(page_content='\n\n\n\n\n\n\n\n\n\nLangChain Python API Reference Documentation.\n\n\nYou will be automatically redirected to the new location of this page.\n\n', metadata={'source': 'https://api.python.langchain.com/en/latest/', 'loc': 'https://api.python.langchain.com/en/latest/', 'lastmod': '2024-02-12T05:26:10.971077+00:00', 'changefreq': 'daily', 'priority': '0.9'})
Add custom scraping rules
The SitemapLoader
uses beautifulsoup4
for the scraping process, and it scrapes every element on the page by default. The SitemapLoader
constructor accepts a custom scraping function. This feature can be helpful to tailor the scraping process to your specific needs; for example, you might want to avoid scraping headers or navigation elements.
The following example shows how to develop and use a custom function to avoid navigation and header elements.
Import the beautifulsoup4
library and define the custom function.
pip install beautifulsoup4
from bs4 import BeautifulSoup
def remove_nav_and_header_elements(content: BeautifulSoup) -> str:
# Find all 'nav' and 'header' elements in the BeautifulSoup object
nav_elements = content.find_all("nav")
header_elements = content.find_all("header")
# Remove each 'nav' and 'header' element from the BeautifulSoup object
for element in nav_elements + header_elements:
element.decompose()
return str(content.get_text())
Add your custom function to the SitemapLoader
object.
loader = SitemapLoader(
"https://api.python.langchain.com/sitemap.xml",
filter_urls=["https://api.python.langchain.com/en/latest/"],
parsing_function=remove_nav_and_header_elements,
)
Local Sitemap
The sitemap loader can also be used to load local files.
sitemap_loader = SitemapLoader(web_path="example_data/sitemap.xml", is_local=True)
docs = sitemap_loader.load()
Related
- Document loader conceptual guide
- Document loader how-to guides