【feature】Commit Message: Optimized PyMuPDFScraper to handle invalid o…

…r defense-mechanism-protected URLs more efficiently, preventing long delays and system crashes.

gpt_researcher/scraper/pymupdf/pymupdf.py

@@ -1,21 +1,65 @@
+import os
+import requests
+import tempfile
+from urllib.parse import urlparse
 from langchain_community.document_loaders import PyMuPDFLoader
 
 
 class PyMuPDFScraper:
 
     def __init__(self, link, session=None):
+        """
+        Initialize the scraper with a link and an optional session.
+
+        Args:
+          link (str): The URL or local file path of the PDF document.
+          session (requests.Session, optional): An optional session for making HTTP requests.
+        """
         self.link = link
         self.session = session
 
+    def is_url(self) -> bool:
+        """
+        Check if the provided `link` is a valid URL.
+
+        Returns:
+          bool: True if the link is a valid URL, False otherwise.
+        """
+        try:
+            result = urlparse(self.link)
+            return all([result.scheme, result.netloc])  # Check for valid scheme and network location
+        except Exception:
+            return False
+
     def scrape(self) -> str:
         """
-        The `scrape` function uses PyMuPDFLoader to load a document from a given link and returns it as
-        a string.
-        
+        The `scrape` function uses PyMuPDFLoader to load a document from the provided link (either URL or local file)
+        and returns the document as a string.
+
         Returns:
-          The `scrape` method is returning a string representation of the `doc` object, which is loaded
-        using PyMuPDFLoader from the provided link.
+          str: A string representation of the loaded document.
         """
-        loader = PyMuPDFLoader(self.link)
-        doc = loader.load()
-        return str(doc)
+        try:
+            if self.is_url():
+                response = requests.get(self.link, timeout=5, stream=True)
+                response.raise_for_status()
+
+                with tempfile.NamedTemporaryFile(delete=False, suffix=".pdf") as temp_file:
+                    temp_filename = temp_file.name  # Get the temporary file name
+                    for chunk in response.iter_content(chunk_size=8192):
+                        temp_file.write(chunk)  # Write the downloaded content to the temporary file
+
+                loader = PyMuPDFLoader(temp_filename)
+                doc = loader.load()
+
+                os.remove(temp_filename)
+            else:
+                loader = PyMuPDFLoader(self.link)
+                doc = loader.load()
+
+            return str(doc)
+
+        except requests.exceptions.Timeout:
+            print(f"Download timed out. Please check the link : {self.link}")
+        except Exception as e:
+            print(f"Error loading PDF : {self.link} {e}")