forked from Archives/langchain
You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
208 lines
6.6 KiB
Python
208 lines
6.6 KiB
Python
"""Loader that loads PDF files."""
|
|
import os
|
|
import tempfile
|
|
from abc import ABC
|
|
from io import StringIO
|
|
from typing import Any, List, Optional
|
|
from urllib.parse import urlparse
|
|
|
|
import requests
|
|
|
|
from langchain.docstore.document import Document
|
|
from langchain.document_loaders.base import BaseLoader
|
|
from langchain.document_loaders.unstructured import UnstructuredFileLoader
|
|
|
|
|
|
class UnstructuredPDFLoader(UnstructuredFileLoader):
|
|
"""Loader that uses unstructured to load PDF files."""
|
|
|
|
def _get_elements(self) -> List:
|
|
from unstructured.partition.pdf import partition_pdf
|
|
|
|
return partition_pdf(filename=self.file_path, **self.unstructured_kwargs)
|
|
|
|
|
|
class BasePDFLoader(BaseLoader, ABC):
|
|
"""Base loader class for PDF files.
|
|
|
|
Defaults to check for local file, but if the file is a web path, it will download it
|
|
to a temporary file, and use that, then clean up the temporary file after completion
|
|
"""
|
|
|
|
file_path: str
|
|
web_path: Optional[str] = None
|
|
|
|
def __init__(self, file_path: str):
|
|
"""Initialize with file path."""
|
|
self.file_path = file_path
|
|
if "~" in self.file_path:
|
|
self.file_path = os.path.expanduser(self.file_path)
|
|
|
|
# If the file is a web path, download it to a temporary file, and use that
|
|
if not os.path.isfile(self.file_path) and self._is_valid_url(self.file_path):
|
|
r = requests.get(self.file_path)
|
|
|
|
if r.status_code != 200:
|
|
raise ValueError(
|
|
"Check the url of your file; returned status code %s"
|
|
% r.status_code
|
|
)
|
|
|
|
self.web_path = self.file_path
|
|
self.temp_file = tempfile.NamedTemporaryFile()
|
|
self.temp_file.write(r.content)
|
|
self.file_path = self.temp_file.name
|
|
elif not os.path.isfile(self.file_path):
|
|
raise ValueError("File path %s is not a valid file or url" % self.file_path)
|
|
|
|
def __del__(self) -> None:
|
|
if hasattr(self, "temp_file"):
|
|
self.temp_file.close()
|
|
|
|
@staticmethod
|
|
def _is_valid_url(url: str) -> bool:
|
|
"""Check if the url is valid."""
|
|
parsed = urlparse(url)
|
|
return bool(parsed.netloc) and bool(parsed.scheme)
|
|
|
|
|
|
class OnlinePDFLoader(BasePDFLoader):
|
|
"""Loader that loads online PDFs."""
|
|
|
|
def load(self) -> List[Document]:
|
|
"""Load documents."""
|
|
loader = UnstructuredPDFLoader(str(self.file_path))
|
|
return loader.load()
|
|
|
|
|
|
class PyPDFLoader(BasePDFLoader):
|
|
"""Loads a PDF with pypdf and chunks at character level.
|
|
|
|
Loader also stores page numbers in metadatas.
|
|
"""
|
|
|
|
def __init__(self, file_path: str):
|
|
"""Initialize with file path."""
|
|
try:
|
|
import pypdf # noqa:F401
|
|
except ImportError:
|
|
raise ValueError(
|
|
"pypdf package not found, please install it with " "`pip install pypdf`"
|
|
)
|
|
super().__init__(file_path)
|
|
|
|
def load(self) -> List[Document]:
|
|
"""Load given path as pages."""
|
|
import pypdf
|
|
|
|
with open(self.file_path, "rb") as pdf_file_obj:
|
|
pdf_reader = pypdf.PdfReader(pdf_file_obj)
|
|
return [
|
|
Document(
|
|
page_content=page.extract_text(),
|
|
metadata={"source": self.file_path, "page": i},
|
|
)
|
|
for i, page in enumerate(pdf_reader.pages)
|
|
]
|
|
|
|
|
|
class PDFMinerLoader(BasePDFLoader):
|
|
"""Loader that uses PDFMiner to load PDF files."""
|
|
|
|
def __init__(self, file_path: str):
|
|
"""Initialize with file path."""
|
|
try:
|
|
from pdfminer.high_level import extract_text # noqa:F401
|
|
except ImportError:
|
|
raise ValueError(
|
|
"pdfminer package not found, please install it with "
|
|
"`pip install pdfminer.six`"
|
|
)
|
|
|
|
super().__init__(file_path)
|
|
|
|
def load(self) -> List[Document]:
|
|
"""Load file."""
|
|
from pdfminer.high_level import extract_text
|
|
|
|
text = extract_text(self.file_path)
|
|
metadata = {"source": self.file_path}
|
|
return [Document(page_content=text, metadata=metadata)]
|
|
|
|
|
|
class PDFMinerPDFasHTMLLoader(BasePDFLoader):
|
|
"""Loader that uses PDFMiner to load PDF files as HTML content."""
|
|
|
|
def __init__(self, file_path: str):
|
|
"""Initialize with file path."""
|
|
try:
|
|
from pdfminer.high_level import extract_text_to_fp # noqa:F401
|
|
except ImportError:
|
|
raise ValueError(
|
|
"pdfminer package not found, please install it with "
|
|
"`pip install pdfminer.six`"
|
|
)
|
|
|
|
super().__init__(file_path)
|
|
|
|
def load(self) -> List[Document]:
|
|
"""Load file."""
|
|
from pdfminer.high_level import extract_text_to_fp
|
|
from pdfminer.layout import LAParams
|
|
from pdfminer.utils import open_filename
|
|
|
|
output_string = StringIO()
|
|
with open_filename(self.file_path, "rb") as fp:
|
|
extract_text_to_fp(
|
|
fp, # type: ignore[arg-type]
|
|
output_string,
|
|
codec="",
|
|
laparams=LAParams(),
|
|
output_type="html",
|
|
)
|
|
metadata = {"source": self.file_path}
|
|
return [Document(page_content=output_string.getvalue(), metadata=metadata)]
|
|
|
|
|
|
class PyMuPDFLoader(BasePDFLoader):
|
|
"""Loader that uses PyMuPDF to load PDF files."""
|
|
|
|
def __init__(self, file_path: str):
|
|
"""Initialize with file path."""
|
|
try:
|
|
import fitz # noqa:F401
|
|
except ImportError:
|
|
raise ValueError(
|
|
"PyMuPDF package not found, please install it with "
|
|
"`pip install pymupdf`"
|
|
)
|
|
|
|
super().__init__(file_path)
|
|
|
|
def load(self, **kwargs: Optional[Any]) -> List[Document]:
|
|
"""Load file."""
|
|
import fitz
|
|
|
|
doc = fitz.open(self.file_path) # open document
|
|
file_path = self.file_path if self.web_path is None else self.web_path
|
|
|
|
return [
|
|
Document(
|
|
page_content=page.get_text(**kwargs).encode("utf-8"),
|
|
metadata=dict(
|
|
{
|
|
"source": file_path,
|
|
"file_path": file_path,
|
|
"page_number": page.number + 1,
|
|
"total_pages": len(doc),
|
|
},
|
|
**{
|
|
k: doc.metadata[k]
|
|
for k in doc.metadata
|
|
if type(doc.metadata[k]) in [str, int]
|
|
}
|
|
),
|
|
)
|
|
for page in doc
|
|
]
|