langchain/libs/community/langchain_community/document_loaders/rss.py
Charlie Marsh 8f38b7a725
multiple: Remove unnecessary Ruff suppression comments (#21050)
## Summary

I ran `ruff check --extend-select RUF100 -n` to identify `# noqa`
comments that weren't having any effect in Ruff, and then `ruff check
--extend-select RUF100 -n --fix` on select files to remove all of the
unnecessary `# noqa: F401` violations. It's possible that these were
needed at some point in the past, but they're not necessary in Ruff
v0.1.15 (used by LangChain) or in the latest release.

Co-authored-by: Erick Friis <erick@langchain.dev>
2024-04-30 17:13:48 +00:00

134 lines
4.8 KiB
Python

import logging
from typing import Any, Iterator, List, Optional, Sequence
from langchain_core.documents import Document
from langchain_community.document_loaders.base import BaseLoader
from langchain_community.document_loaders.news import NewsURLLoader
logger = logging.getLogger(__name__)
class RSSFeedLoader(BaseLoader):
"""Load news articles from `RSS` feeds using `Unstructured`.
Args:
urls: URLs for RSS feeds to load. Each articles in the feed is loaded into its own document.
opml: OPML file to load feed urls from. Only one of urls or opml should be provided. The value
can be a URL string, or OPML markup contents as byte or string.
continue_on_failure: If True, continue loading documents even if
loading fails for a particular URL.
show_progress_bar: If True, use tqdm to show a loading progress bar. Requires
tqdm to be installed, ``pip install tqdm``.
**newsloader_kwargs: Any additional named arguments to pass to
NewsURLLoader.
Example:
.. code-block:: python
from langchain_community.document_loaders import RSSFeedLoader
loader = RSSFeedLoader(
urls=["<url-1>", "<url-2>"],
)
docs = loader.load()
The loader uses feedparser to parse RSS feeds. The feedparser library is not installed by default so you should
install it if using this loader:
https://pythonhosted.org/feedparser/
If you use OPML, you should also install listparser:
https://pythonhosted.org/listparser/
Finally, newspaper is used to process each article:
https://newspaper.readthedocs.io/en/latest/
""" # noqa: E501
def __init__(
self,
urls: Optional[Sequence[str]] = None,
opml: Optional[str] = None,
continue_on_failure: bool = True,
show_progress_bar: bool = False,
**newsloader_kwargs: Any,
) -> None:
"""Initialize with urls or OPML."""
if (urls is None) == (
opml is None
): # This is True if both are None or neither is None
raise ValueError(
"Provide either the urls or the opml argument, but not both."
)
self.urls = urls
self.opml = opml
self.continue_on_failure = continue_on_failure
self.show_progress_bar = show_progress_bar
self.newsloader_kwargs = newsloader_kwargs
def load(self) -> List[Document]:
iter = self.lazy_load()
if self.show_progress_bar:
try:
from tqdm import tqdm
except ImportError as e:
raise ImportError(
"Package tqdm must be installed if show_progress_bar=True. "
"Please install with 'pip install tqdm' or set "
"show_progress_bar=False."
) from e
iter = tqdm(iter)
return list(iter)
@property
def _get_urls(self) -> Sequence[str]:
if self.urls:
return self.urls
try:
import listparser
except ImportError as e:
raise ImportError(
"Package listparser must be installed if the opml arg is used. "
"Please install with 'pip install listparser' or use the "
"urls arg instead."
) from e
rss = listparser.parse(self.opml)
return [feed.url for feed in rss.feeds]
def lazy_load(self) -> Iterator[Document]:
try:
import feedparser
except ImportError:
raise ImportError(
"feedparser package not found, please install it with "
"`pip install feedparser`"
)
for url in self._get_urls:
try:
feed = feedparser.parse(url)
if getattr(feed, "bozo", False):
raise ValueError(
f"Error fetching {url}, exception: {feed.bozo_exception}"
)
except Exception as e:
if self.continue_on_failure:
logger.error(f"Error fetching {url}, exception: {e}")
continue
else:
raise e
try:
for entry in feed.entries:
loader = NewsURLLoader(
urls=[entry.link],
**self.newsloader_kwargs,
)
article = loader.load()[0]
article.metadata["feed"] = url
yield article
except Exception as e:
if self.continue_on_failure:
logger.error(f"Error processing entry {entry.link}, exception: {e}")
continue
else:
raise e