add metadata to pdf extraction (#2278)

backend/danswer/connectors/file/connector.py

@@ -23,7 +23,7 @@
 from danswer.file_processing.extract_file_text import get_file_ext
 from danswer.file_processing.extract_file_text import is_text_file_extension
 from danswer.file_processing.extract_file_text import load_files_from_zip
-from danswer.file_processing.extract_file_text import pdf_to_text
+from danswer.file_processing.extract_file_text import read_pdf_file
 from danswer.file_processing.extract_file_text import read_text_file
 from danswer.file_store.file_store import get_default_file_store
 from danswer.utils.logger import setup_logger
@@ -75,7 +75,7 @@ def _process_file(
 
     # Using the PDF reader function directly to pass in password cleanly
     elif extension == ".pdf":
-        file_content_raw = pdf_to_text(file=file, pdf_pass=pdf_pass)
+        file_content_raw, file_metadata = read_pdf_file(file=file, pdf_pass=pdf_pass)
 
     else:
         file_content_raw = extract_file_text(

backend/danswer/connectors/google_drive/connector.py

@@ -41,8 +41,8 @@
 from danswer.connectors.models import Document
 from danswer.connectors.models import Section
 from danswer.file_processing.extract_file_text import docx_to_text
-from danswer.file_processing.extract_file_text import pdf_to_text
 from danswer.file_processing.extract_file_text import pptx_to_text
+from danswer.file_processing.extract_file_text import read_pdf_file
 from danswer.utils.batching import batch_generator
 from danswer.utils.logger import setup_logger
 
@@ -334,7 +334,8 @@ def extract_text(file: dict[str, str], service: discovery.Resource) -> str:
         return docx_to_text(file=io.BytesIO(response))
     elif mime_type == GDriveMimeType.PDF.value:
         response = service.files().get_media(fileId=file["id"]).execute()
-        return pdf_to_text(file=io.BytesIO(response))
+        text, _ = read_pdf_file(file=io.BytesIO(response))
+        return text
     elif mime_type == GDriveMimeType.POWERPOINT.value:
         response = service.files().get_media(fileId=file["id"]).execute()
         return pptx_to_text(file=io.BytesIO(response))

backend/danswer/connectors/web/connector.py

@@ -27,7 +27,7 @@
 from danswer.connectors.interfaces import LoadConnector
 from danswer.connectors.models import Document
 from danswer.connectors.models import Section
-from danswer.file_processing.extract_file_text import pdf_to_text
+from danswer.file_processing.extract_file_text import read_pdf_file
 from danswer.file_processing.html_utils import web_html_cleanup
 from danswer.utils.logger import setup_logger
 from danswer.utils.sitemap import list_pages_for_site
@@ -284,15 +284,17 @@ def load_from_state(self) -> GenerateDocumentsOutput:
                 if current_url.split(".")[-1] == "pdf":
                     # PDF files are not checked for links
                     response = requests.get(current_url)
-                    page_text = pdf_to_text(file=io.BytesIO(response.content))
+                    page_text, metadata = read_pdf_file(
+                        file=io.BytesIO(response.content)
+                    )
 
                     doc_batch.append(
                         Document(
                             id=current_url,
                             sections=[Section(link=current_url, text=page_text)],
                             source=DocumentSource.WEB,
                             semantic_identifier=current_url.split("/")[-1],
-                            metadata={},
+                            metadata=metadata,
                         )
                     )
                     continue

backend/danswer/file_processing/extract_file_text.py

@@ -177,7 +177,11 @@ def read_text_file(
     return file_content_raw, metadata
 
 
-def pdf_to_text(file: IO[Any], pdf_pass: str | None = None) -> str:
+def read_pdf_file(
+    file: IO[Any],
+    pdf_pass: str | None = None,
+) -> str:
+    metadata = {}
     try:
         pdf_reader = PdfReader(file)
 
@@ -197,8 +201,16 @@ def pdf_to_text(file: IO[Any], pdf_pass: str | None = None) -> str:
                 # can be discoverable by title.
                 return ""
 
-        return TEXT_SECTION_SEPARATOR.join(
-            page.extract_text() for page in pdf_reader.pages
+        # Extract metadata from the PDF, removing leading '/' from keys if present
+        # This standardizes the metadata keys for consistency
+        metadata = {
+            k[1:] if k.startswith("/") else k: v for k, v in pdf_reader.metadata.items()
+        }
+        return (
+            TEXT_SECTION_SEPARATOR.join(
+                page.extract_text() for page in pdf_reader.pages
+            ),
+            metadata,
         )
     except PdfStreamError:
         logger.exception("PDF file is not a valid PDF")
@@ -207,7 +219,7 @@ def pdf_to_text(file: IO[Any], pdf_pass: str | None = None) -> str:
 
     # File is still discoverable by title
     # but the contents are not included as they cannot be parsed
-    return ""
+    return "", metadata
 
 
 def docx_to_text(file: IO[Any]) -> str:
@@ -273,7 +285,7 @@ def extract_file_text(
     break_on_unprocessable: bool = True,
 ) -> str:
     extension_to_function: dict[str, Callable[[IO[Any]], str]] = {
-        ".pdf": pdf_to_text,
+        ".pdf": read_pdf_file,
         ".docx": docx_to_text,
         ".pptx": pptx_to_text,
         ".xlsx": xlsx_to_text,