Dev2049/pypdfium2 (#4209)

thanks @jerrytigerxu for the addition!

---------

Co-authored-by: Jere Xu <jtxu2008@gmail.com>
Co-authored-by: jerrytigerxu <jere.tiger.xu@gmailc.om>

docs/modules/indexes/document_loaders/examples/pdf.ipynb

@@ -372,6 +372,44 @@
   {
    "cell_type": "code",
    "execution_count": 9,
+   "id": "483720b5",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "data = loader.load()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "96351714",
+   "metadata": {},
+   "source": [
+    "# Using PyPDFium2"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "id": "003fcc1d",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from langchain.document_loaders import PyPDFium2Loader"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "id": "46766e29",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "loader = PyPDFium2Loader(\"example_data/layout-parser-paper.pdf\")"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
    "id": "010d5cdd",
    "metadata": {},
    "outputs": [],
@@ -662,7 +700,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.10.6"
+   "version": "3.11.3"
   }
  },
  "nbformat": 4,

langchain/document_loaders/__init__.py

@@ -61,6 +61,7 @@ from langchain.document_loaders.pdf import (
     PDFMinerPDFasHTMLLoader,
     PyMuPDFLoader,
     PyPDFDirectoryLoader,
+    PyPDFium2Loader,
     PyPDFLoader,
     UnstructuredPDFLoader,
 )
@@ -161,6 +162,7 @@ __all__ = [
     "PlaywrightURLLoader",
     "PyMuPDFLoader",
     "PyPDFLoader",
+    "PyPDFium2Loader",
     "PythonLoader",
     "ReadTheDocsLoader",
     "RoamLoader",

langchain/document_loaders/pdf.py

@@ -115,6 +115,34 @@ class PyPDFLoader(BasePDFLoader):
             ]
 
 
+class PyPDFium2Loader(BasePDFLoader):
+    """Loads a PDF with pypdfium2 and chunks at character level."""
+
+    def __init__(self, file_path: str):
+        """Initialize with file path."""
+        try:
+            import pypdfium2  # noqa:F401
+        except ImportError:
+            raise ValueError(
+                "pypdfium2 package not found, please install it with"
+                " `pip install pypdfium2`"
+            )
+        super().__init__(file_path)
+
+    def load(self) -> List[Document]:
+        """Load given path as pages."""
+        import pypdfium2
+
+        with open(self.file_path, "rb") as f:
+            pdf_reader = pypdfium2.PdfDocument(f)
+            docs = []
+            for i, page in enumerate(pdf_reader):
+                content = page.get_textpage().get_text_range()
+                metadata = {"source": self.file_path, "page": i}
+                docs.append(Document(page_content=content, metadata=metadata))
+            return docs
+
+
 class PyPDFDirectoryLoader(BaseLoader):
     """Loads a directory with PDF files with pypdf and chunks at character level.
 

tests/integration_tests/document_loaders/test_pdf.py

@@ -1,12 +1,14 @@
 from pathlib import Path
 
 from langchain.document_loaders import (
+    MathpixPDFLoader,
     PDFMinerLoader,
     PDFMinerPDFasHTMLLoader,
     PyMuPDFLoader,
+    PyPDFium2Loader,
+    PyPDFLoader,
     UnstructuredPDFLoader,
 )
-from langchain.document_loaders.pdf import MathpixPDFLoader
 
 
 def test_unstructured_pdf_loader() -> None:
@@ -48,6 +50,36 @@ def test_pdfminer_pdf_as_html_loader() -> None:
     assert len(docs) == 1
 
 
+def test_pypdf_loader() -> None:
+    """Test PyPDFLoader."""
+    file_path = Path(__file__).parent.parent / "examples/hello.pdf"
+    loader = PyPDFLoader(str(file_path))
+    docs = loader.load()
+
+    assert len(docs) == 1
+
+    file_path = Path(__file__).parent.parent / "examples/layout-parser-paper.pdf"
+    loader = PyPDFLoader(str(file_path))
+
+    docs = loader.load()
+    assert len(docs) == 16
+
+
+def test_pypdfium2_loader() -> None:
+    """Test PyPDFium2Loader."""
+    file_path = Path(__file__).parent.parent / "examples/hello.pdf"
+    loader = PyPDFium2Loader(str(file_path))
+    docs = loader.load()
+
+    assert len(docs) == 1
+
+    file_path = Path(__file__).parent.parent / "examples/layout-parser-paper.pdf"
+    loader = PyPDFium2Loader(str(file_path))
+
+    docs = loader.load()
+    assert len(docs) == 16
+
+
 def test_pymupdf_loader() -> None:
     """Test PyMuPDF loader."""
     file_path = Path(__file__).parent.parent / "examples/hello.pdf"