Ignoring book if missing.

utils.py

@@ -183,12 +183,13 @@ def get_links(index_url, paths):
 
 def get_document_data(book_file, book_url):
     document_list = []
-    with open(book_file, 'rb') as f:
-        pdf_reader = PdfReader(f)
-        for i in range(len(pdf_reader.pages)):
-            page_text = pdf_reader.pages[i].extract_text()
-            metadata = {"source": book_url}
-            document_list.append(Document(page_content=page_text, metadata=metadata))
+    if os.path.isfile(book_file):
+        with open(book_file, 'rb') as f:
+            pdf_reader = PdfReader(f)
+            for i in range(len(pdf_reader.pages)):
+                page_text = pdf_reader.pages[i].extract_text()
+                metadata = {"source": book_url}
+                document_list.append(Document(page_content=page_text, metadata=metadata))
 
     # print("document list" + str(len(document_list)))
     return document_list