langchain/libs/community/langchain_community/document_loaders/pdf.py

753 lines
26 KiB
Python

import json
import logging
import os
import tempfile
import time
from abc import ABC
from io import StringIO
from pathlib import Path
from typing import Any, Dict, Iterator, List, Mapping, Optional, Sequence, Union
from urllib.parse import urlparse
import requests
from langchain_core.documents import Document
from langchain_core.utils import get_from_dict_or_env
from langchain_community.document_loaders.base import BaseLoader
from langchain_community.document_loaders.blob_loaders import Blob
from langchain_community.document_loaders.parsers.pdf import (
AmazonTextractPDFParser,
DocumentIntelligenceParser,
PDFMinerParser,
PDFPlumberParser,
PyMuPDFParser,
PyPDFium2Parser,
PyPDFParser,
)
from langchain_community.document_loaders.unstructured import UnstructuredFileLoader
logger = logging.getLogger(__file__)
class UnstructuredPDFLoader(UnstructuredFileLoader):
"""Load `PDF` files using `Unstructured`.
You can run the loader in one of two modes: "single" and "elements".
If you use "single" mode, the document will be returned as a single
langchain Document object. If you use "elements" mode, the unstructured
library will split the document into elements such as Title and NarrativeText.
You can pass in additional unstructured kwargs after mode to apply
different unstructured settings.
Examples
--------
from langchain_community.document_loaders import UnstructuredPDFLoader
loader = UnstructuredPDFLoader(
"example.pdf", mode="elements", strategy="fast",
)
docs = loader.load()
References
----------
https://unstructured-io.github.io/unstructured/bricks.html#partition-pdf
"""
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.
If the file is a web path, it will download it to a temporary file, use it, then
clean up the temporary file after completion.
"""
def __init__(self, file_path: str, *, headers: Optional[Dict] = None):
"""Initialize with a file path.
Args:
file_path: Either a local, S3 or web path to a PDF file.
headers: Headers to use for GET request to download a file from a web path.
"""
self.file_path = file_path
self.web_path = None
self.headers = headers
if "~" in self.file_path:
self.file_path = os.path.expanduser(self.file_path)
# If the file is a web path or S3, 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):
self.temp_dir = tempfile.TemporaryDirectory()
_, suffix = os.path.splitext(self.file_path)
temp_pdf = os.path.join(self.temp_dir.name, f"tmp{suffix}")
self.web_path = self.file_path
if not self._is_s3_url(self.file_path):
r = requests.get(self.file_path, headers=self.headers)
if r.status_code != 200:
raise ValueError(
"Check the url of your file; returned status code %s"
% r.status_code
)
with open(temp_pdf, mode="wb") as f:
f.write(r.content)
self.file_path = str(temp_pdf)
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_dir"):
self.temp_dir.cleanup()
@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)
@staticmethod
def _is_s3_url(url: str) -> bool:
"""check if the url is S3"""
try:
result = urlparse(url)
if result.scheme == "s3" and result.netloc:
return True
return False
except ValueError:
return False
@property
def source(self) -> str:
return self.web_path if self.web_path is not None else self.file_path
class OnlinePDFLoader(BasePDFLoader):
"""Load online `PDF`."""
def load(self) -> List[Document]:
"""Load documents."""
loader = UnstructuredPDFLoader(str(self.file_path))
return loader.load()
class PyPDFLoader(BasePDFLoader):
"""Load PDF using pypdf into list of documents.
Loader chunks by page and stores page numbers in metadata.
"""
def __init__(
self,
file_path: str,
password: Optional[Union[str, bytes]] = None,
headers: Optional[Dict] = None,
extract_images: bool = False,
) -> None:
"""Initialize with a file path."""
try:
import pypdf # noqa:F401
except ImportError:
raise ImportError(
"pypdf package not found, please install it with " "`pip install pypdf`"
)
super().__init__(file_path, headers=headers)
self.parser = PyPDFParser(password=password, extract_images=extract_images)
def lazy_load(
self,
) -> Iterator[Document]:
"""Lazy load given path as pages."""
if self.web_path:
blob = Blob.from_data(open(self.file_path, "rb").read(), path=self.web_path)
else:
blob = Blob.from_path(self.file_path)
yield from self.parser.parse(blob)
class PyPDFium2Loader(BasePDFLoader):
"""Load `PDF` using `pypdfium2` and chunks at character level."""
def __init__(
self,
file_path: str,
*,
headers: Optional[Dict] = None,
extract_images: bool = False,
):
"""Initialize with a file path."""
super().__init__(file_path, headers=headers)
self.parser = PyPDFium2Parser(extract_images=extract_images)
def load(self) -> List[Document]:
"""Load given path as pages."""
return list(self.lazy_load())
def lazy_load(
self,
) -> Iterator[Document]:
"""Lazy load given path as pages."""
if self.web_path:
blob = Blob.from_data(open(self.file_path, "rb").read(), path=self.web_path)
else:
blob = Blob.from_path(self.file_path)
yield from self.parser.parse(blob)
class PyPDFDirectoryLoader(BaseLoader):
"""Load a directory with `PDF` files using `pypdf` and chunks at character level.
Loader also stores page numbers in metadata.
"""
def __init__(
self,
path: str,
glob: str = "**/[!.]*.pdf",
silent_errors: bool = False,
load_hidden: bool = False,
recursive: bool = False,
extract_images: bool = False,
):
self.path = path
self.glob = glob
self.load_hidden = load_hidden
self.recursive = recursive
self.silent_errors = silent_errors
self.extract_images = extract_images
@staticmethod
def _is_visible(path: Path) -> bool:
return not any(part.startswith(".") for part in path.parts)
def load(self) -> List[Document]:
p = Path(self.path)
docs = []
items = p.rglob(self.glob) if self.recursive else p.glob(self.glob)
for i in items:
if i.is_file():
if self._is_visible(i.relative_to(p)) or self.load_hidden:
try:
loader = PyPDFLoader(str(i), extract_images=self.extract_images)
sub_docs = loader.load()
for doc in sub_docs:
doc.metadata["source"] = str(i)
docs.extend(sub_docs)
except Exception as e:
if self.silent_errors:
logger.warning(e)
else:
raise e
return docs
class PDFMinerLoader(BasePDFLoader):
"""Load `PDF` files using `PDFMiner`."""
def __init__(
self,
file_path: str,
*,
headers: Optional[Dict] = None,
extract_images: bool = False,
concatenate_pages: bool = True,
) -> None:
"""Initialize with file path.
Args:
extract_images: Whether to extract images from PDF.
concatenate_pages: If True, concatenate all PDF pages into one a single
document. Otherwise, return one document per page.
"""
try:
from pdfminer.high_level import extract_text # noqa:F401
except ImportError:
raise ImportError(
"`pdfminer` package not found, please install it with "
"`pip install pdfminer.six`"
)
super().__init__(file_path, headers=headers)
self.parser = PDFMinerParser(
extract_images=extract_images, concatenate_pages=concatenate_pages
)
def load(self) -> List[Document]:
"""Eagerly load the content."""
return list(self.lazy_load())
def lazy_load(
self,
) -> Iterator[Document]:
"""Lazily load documents."""
if self.web_path:
blob = Blob.from_data(open(self.file_path, "rb").read(), path=self.web_path)
else:
blob = Blob.from_path(self.file_path)
yield from self.parser.parse(blob)
class PDFMinerPDFasHTMLLoader(BasePDFLoader):
"""Load `PDF` files as HTML content using `PDFMiner`."""
def __init__(self, file_path: str, *, headers: Optional[Dict] = None):
"""Initialize with a file path."""
try:
from pdfminer.high_level import extract_text_to_fp # noqa:F401
except ImportError:
raise ImportError(
"`pdfminer` package not found, please install it with "
"`pip install pdfminer.six`"
)
super().__init__(file_path, headers=headers)
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,
output_string,
codec="",
laparams=LAParams(),
output_type="html",
)
metadata = {
"source": self.file_path if self.web_path is None else self.web_path
}
return [Document(page_content=output_string.getvalue(), metadata=metadata)]
class PyMuPDFLoader(BasePDFLoader):
"""Load `PDF` files using `PyMuPDF`."""
def __init__(
self,
file_path: str,
*,
headers: Optional[Dict] = None,
extract_images: bool = False,
**kwargs: Any,
) -> None:
"""Initialize with a file path."""
try:
import fitz # noqa:F401
except ImportError:
raise ImportError(
"`PyMuPDF` package not found, please install it with "
"`pip install pymupdf`"
)
super().__init__(file_path, headers=headers)
self.extract_images = extract_images
self.text_kwargs = kwargs
def load(self, **kwargs: Any) -> List[Document]:
"""Load file."""
if kwargs:
logger.warning(
f"Received runtime arguments {kwargs}. Passing runtime args to `load`"
f" is deprecated. Please pass arguments during initialization instead."
)
text_kwargs = {**self.text_kwargs, **kwargs}
parser = PyMuPDFParser(
text_kwargs=text_kwargs, extract_images=self.extract_images
)
if self.web_path:
blob = Blob.from_data(open(self.file_path, "rb").read(), path=self.web_path)
else:
blob = Blob.from_path(self.file_path)
return parser.parse(blob)
# MathpixPDFLoader implementation taken largely from Daniel Gross's:
# https://gist.github.com/danielgross/3ab4104e14faccc12b49200843adab21
class MathpixPDFLoader(BasePDFLoader):
"""Load `PDF` files using `Mathpix` service."""
def __init__(
self,
file_path: str,
processed_file_format: str = "md",
max_wait_time_seconds: int = 500,
should_clean_pdf: bool = False,
extra_request_data: Optional[Dict[str, Any]] = None,
**kwargs: Any,
) -> None:
"""Initialize with a file path.
Args:
file_path: a file for loading.
processed_file_format: a format of the processed file. Default is "md".
max_wait_time_seconds: a maximum time to wait for the response from
the server. Default is 500.
should_clean_pdf: a flag to clean the PDF file. Default is False.
extra_request_data: Additional request data.
**kwargs: additional keyword arguments.
"""
self.mathpix_api_key = get_from_dict_or_env(
kwargs, "mathpix_api_key", "MATHPIX_API_KEY"
)
self.mathpix_api_id = get_from_dict_or_env(
kwargs, "mathpix_api_id", "MATHPIX_API_ID"
)
# The base class isn't expecting these and doesn't collect **kwargs
kwargs.pop("mathpix_api_key", None)
kwargs.pop("mathpix_api_id", None)
super().__init__(file_path, **kwargs)
self.processed_file_format = processed_file_format
self.extra_request_data = (
extra_request_data if extra_request_data is not None else {}
)
self.max_wait_time_seconds = max_wait_time_seconds
self.should_clean_pdf = should_clean_pdf
@property
def _mathpix_headers(self) -> Dict[str, str]:
return {"app_id": self.mathpix_api_id, "app_key": self.mathpix_api_key}
@property
def url(self) -> str:
return "https://api.mathpix.com/v3/pdf"
@property
def data(self) -> dict:
options = {
"conversion_formats": {self.processed_file_format: True},
**self.extra_request_data,
}
return {"options_json": json.dumps(options)}
def send_pdf(self) -> str:
with open(self.file_path, "rb") as f:
files = {"file": f}
response = requests.post(
self.url, headers=self._mathpix_headers, files=files, data=self.data
)
response_data = response.json()
if "error" in response_data:
raise ValueError(f"Mathpix request failed: {response_data['error']}")
if "pdf_id" in response_data:
pdf_id = response_data["pdf_id"]
return pdf_id
else:
raise ValueError("Unable to send PDF to Mathpix.")
def wait_for_processing(self, pdf_id: str) -> None:
"""Wait for processing to complete.
Args:
pdf_id: a PDF id.
Returns: None
"""
url = self.url + "/" + pdf_id
for _ in range(0, self.max_wait_time_seconds, 5):
response = requests.get(url, headers=self._mathpix_headers)
response_data = response.json()
# This indicates an error with the request (e.g. auth problems)
error = response_data.get("error", None)
error_info = response_data.get("error_info", None)
if error is not None:
error_msg = f"Unable to retrieve PDF from Mathpix: {error}"
if error_info is not None:
error_msg += f" ({error_info['id']})"
raise ValueError(error_msg)
status = response_data.get("status", None)
if status == "completed":
return
elif status == "error":
# This indicates an error with the PDF processing
raise ValueError("Unable to retrieve PDF from Mathpix")
else:
print(f"Status: {status}, waiting for processing to complete") # noqa: T201
time.sleep(5)
raise TimeoutError
def get_processed_pdf(self, pdf_id: str) -> str:
self.wait_for_processing(pdf_id)
url = f"{self.url}/{pdf_id}.{self.processed_file_format}"
response = requests.get(url, headers=self._mathpix_headers)
return response.content.decode("utf-8")
def clean_pdf(self, contents: str) -> str:
"""Clean the PDF file.
Args:
contents: a PDF file contents.
Returns:
"""
contents = "\n".join(
[line for line in contents.split("\n") if not line.startswith("![]")]
)
# replace \section{Title} with # Title
contents = contents.replace("\\section{", "# ").replace("}", "")
# replace the "\" slash that Mathpix adds to escape $, %, (, etc.
contents = (
contents.replace(r"\$", "$")
.replace(r"\%", "%")
.replace(r"\(", "(")
.replace(r"\)", ")")
)
return contents
def load(self) -> List[Document]:
pdf_id = self.send_pdf()
contents = self.get_processed_pdf(pdf_id)
if self.should_clean_pdf:
contents = self.clean_pdf(contents)
metadata = {"source": self.source, "file_path": self.source, "pdf_id": pdf_id}
return [Document(page_content=contents, metadata=metadata)]
class PDFPlumberLoader(BasePDFLoader):
"""Load `PDF` files using `pdfplumber`."""
def __init__(
self,
file_path: str,
text_kwargs: Optional[Mapping[str, Any]] = None,
dedupe: bool = False,
headers: Optional[Dict] = None,
extract_images: bool = False,
) -> None:
"""Initialize with a file path."""
try:
import pdfplumber # noqa:F401
except ImportError:
raise ImportError(
"pdfplumber package not found, please install it with "
"`pip install pdfplumber`"
)
super().__init__(file_path, headers=headers)
self.text_kwargs = text_kwargs or {}
self.dedupe = dedupe
self.extract_images = extract_images
def load(self) -> List[Document]:
"""Load file."""
parser = PDFPlumberParser(
text_kwargs=self.text_kwargs,
dedupe=self.dedupe,
extract_images=self.extract_images,
)
if self.web_path:
blob = Blob.from_data(open(self.file_path, "rb").read(), path=self.web_path)
else:
blob = Blob.from_path(self.file_path)
return parser.parse(blob)
class AmazonTextractPDFLoader(BasePDFLoader):
"""Load `PDF` files from a local file system, HTTP or S3.
To authenticate, the AWS client uses the following methods to
automatically load credentials:
https://boto3.amazonaws.com/v1/documentation/api/latest/guide/credentials.html
If a specific credential profile should be used, you must pass
the name of the profile from the ~/.aws/credentials file that is to be used.
Make sure the credentials / roles used have the required policies to
access the Amazon Textract service.
Example:
.. code-block:: python
from langchain_community.document_loaders import AmazonTextractPDFLoader
loader = AmazonTextractPDFLoader(
file_path="s3://pdfs/myfile.pdf"
)
document = loader.load()
"""
def __init__(
self,
file_path: str,
textract_features: Optional[Sequence[str]] = None,
client: Optional[Any] = None,
credentials_profile_name: Optional[str] = None,
region_name: Optional[str] = None,
endpoint_url: Optional[str] = None,
headers: Optional[Dict] = None,
) -> None:
"""Initialize the loader.
Args:
file_path: A file, url or s3 path for input file
textract_features: Features to be used for extraction, each feature
should be passed as a str that conforms to the enum
`Textract_Features`, see `amazon-textract-caller` pkg
client: boto3 textract client (Optional)
credentials_profile_name: AWS profile name, if not default (Optional)
region_name: AWS region, eg us-east-1 (Optional)
endpoint_url: endpoint url for the textract service (Optional)
"""
super().__init__(file_path, headers=headers)
try:
import textractcaller as tc # noqa: F401
except ImportError:
raise ModuleNotFoundError(
"Could not import amazon-textract-caller python package. "
"Please install it with `pip install amazon-textract-caller`."
)
if textract_features:
features = [tc.Textract_Features[x] for x in textract_features]
else:
features = []
if credentials_profile_name or region_name or endpoint_url:
try:
import boto3
if credentials_profile_name is not None:
session = boto3.Session(profile_name=credentials_profile_name)
else:
# use default credentials
session = boto3.Session()
client_params = {}
if region_name:
client_params["region_name"] = region_name
if endpoint_url:
client_params["endpoint_url"] = endpoint_url
client = session.client("textract", **client_params)
except ImportError:
raise ModuleNotFoundError(
"Could not import boto3 python package. "
"Please install it with `pip install boto3`."
)
except Exception as e:
raise ValueError(
"Could not load credentials to authenticate with AWS client. "
"Please check that credentials in the specified "
"profile name are valid."
) from e
self.parser = AmazonTextractPDFParser(textract_features=features, client=client)
def load(self) -> List[Document]:
"""Load given path as pages."""
return list(self.lazy_load())
def lazy_load(
self,
) -> Iterator[Document]:
"""Lazy load documents"""
# the self.file_path is local, but the blob has to include
# the S3 location if the file originated from S3 for multi-page documents
# raises ValueError when multi-page and not on S3"""
if self.web_path and self._is_s3_url(self.web_path):
blob = Blob(path=self.web_path)
else:
blob = Blob.from_path(self.file_path)
if AmazonTextractPDFLoader._get_number_of_pages(blob) > 1:
raise ValueError(
f"the file {blob.path} is a multi-page document, \
but not stored on S3. \
Textract requires multi-page documents to be on S3."
)
yield from self.parser.parse(blob)
@staticmethod
def _get_number_of_pages(blob: Blob) -> int:
try:
import pypdf
from PIL import Image, ImageSequence
except ImportError:
raise ModuleNotFoundError(
"Could not import pypdf or Pilloe python package. "
"Please install it with `pip install pypdf Pillow`."
)
if blob.mimetype == "application/pdf":
with blob.as_bytes_io() as input_pdf_file:
pdf_reader = pypdf.PdfReader(input_pdf_file)
return len(pdf_reader.pages)
elif blob.mimetype == "image/tiff":
num_pages = 0
img = Image.open(blob.as_bytes())
for _, _ in enumerate(ImageSequence.Iterator(img)):
num_pages += 1
return num_pages
elif blob.mimetype in ["image/png", "image/jpeg"]:
return 1
else:
raise ValueError(f"unsupported mime type: {blob.mimetype}")
class DocumentIntelligenceLoader(BasePDFLoader):
"""Loads a PDF with Azure Document Intelligence"""
def __init__(
self,
file_path: str,
client: Any,
model: str = "prebuilt-document",
headers: Optional[Dict] = None,
) -> None:
"""
Initialize the object for file processing with Azure Document Intelligence
(formerly Form Recognizer).
This constructor initializes a DocumentIntelligenceParser object to be used
for parsing files using the Azure Document Intelligence API. The load method
generates a Document node including metadata (source blob and page number)
for each page.
Parameters:
-----------
file_path : str
The path to the file that needs to be parsed.
client: Any
A DocumentAnalysisClient to perform the analysis of the blob
model : str
The model name or ID to be used for form recognition in Azure.
Examples:
---------
>>> obj = DocumentIntelligenceLoader(
... file_path="path/to/file",
... client=client,
... model="prebuilt-document"
... )
"""
self.parser = DocumentIntelligenceParser(client=client, model=model)
super().__init__(file_path, headers=headers)
def load(self) -> List[Document]:
"""Load given path as pages."""
return list(self.lazy_load())
def lazy_load(
self,
) -> Iterator[Document]:
"""Lazy load given path as pages."""
blob = Blob.from_path(self.file_path)
yield from self.parser.parse(blob)