langchain/libs/community/langchain_community/document_loaders/email.py
mwmajewsk f7a1fd91b8
community: better support of pathlib paths in document loaders (#18396)
So this arose from the
https://github.com/langchain-ai/langchain/pull/18397 problem of document
loaders not supporting `pathlib.Path`.

This pull request provides more uniform support for Path as an argument.
The core ideas for this upgrade: 
- if there is a local file path used as an argument, it should be
supported as `pathlib.Path`
- if there are some external calls that may or may not support Pathlib,
the argument is immidiately converted to `str`
- if there `self.file_path` is used in a way that it allows for it to
stay pathlib without conversion, is is only converted for the metadata.

Twitter handle: https://twitter.com/mwmajewsk
2024-03-26 11:51:52 -04:00

119 lines
3.7 KiB
Python

import os
from pathlib import Path
from typing import Any, Iterator, List, Union
from langchain_core.documents import Document
from langchain_community.document_loaders.base import BaseLoader
from langchain_community.document_loaders.unstructured import (
UnstructuredFileLoader,
satisfies_min_unstructured_version,
)
class UnstructuredEmailLoader(UnstructuredFileLoader):
"""Load email files using `Unstructured`.
Works with both
.eml and .msg files. You can process attachments in addition to the
e-mail message itself by passing process_attachments=True into the
constructor for the loader. By default, attachments will be processed
with the unstructured partition function. If you already know the document
types of the attachments, you can specify another partitioning function
with the attachment partitioner kwarg.
Example
-------
from langchain_community.document_loaders import UnstructuredEmailLoader
loader = UnstructuredEmailLoader("example_data/fake-email.eml", mode="elements")
loader.load()
Example
-------
from langchain_community.document_loaders import UnstructuredEmailLoader
loader = UnstructuredEmailLoader(
"example_data/fake-email-attachment.eml",
mode="elements",
process_attachments=True,
)
loader.load()
"""
def __init__(
self,
file_path: Union[str, Path],
mode: str = "single",
**unstructured_kwargs: Any,
):
process_attachments = unstructured_kwargs.get("process_attachments")
attachment_partitioner = unstructured_kwargs.get("attachment_partitioner")
if process_attachments and attachment_partitioner is None:
from unstructured.partition.auto import partition
unstructured_kwargs["attachment_partitioner"] = partition
super().__init__(file_path=file_path, mode=mode, **unstructured_kwargs)
def _get_elements(self) -> List:
from unstructured.file_utils.filetype import FileType, detect_filetype
filetype = detect_filetype(self.file_path)
if filetype == FileType.EML:
from unstructured.partition.email import partition_email
return partition_email(filename=self.file_path, **self.unstructured_kwargs)
elif satisfies_min_unstructured_version("0.5.8") and filetype == FileType.MSG:
from unstructured.partition.msg import partition_msg
return partition_msg(filename=self.file_path, **self.unstructured_kwargs)
else:
raise ValueError(
f"Filetype {filetype} is not supported in UnstructuredEmailLoader."
)
class OutlookMessageLoader(BaseLoader):
"""
Loads Outlook Message files using extract_msg.
https://github.com/TeamMsgExtractor/msg-extractor
"""
def __init__(self, file_path: Union[str, Path]):
"""Initialize with a file path.
Args:
file_path: The path to the Outlook Message file.
"""
self.file_path = str(file_path)
if not os.path.isfile(self.file_path):
raise ValueError(f"File path {self.file_path} is not a valid file")
try:
import extract_msg # noqa:F401
except ImportError:
raise ImportError(
"extract_msg is not installed. Please install it with "
"`pip install extract_msg`"
)
def lazy_load(self) -> Iterator[Document]:
import extract_msg
msg = extract_msg.Message(self.file_path)
yield Document(
page_content=msg.body,
metadata={
"source": self.file_path,
"subject": msg.subject,
"sender": msg.sender,
"date": msg.date,
},
)