Update app.py

app.py

@@ -6,13 +6,13 @@ import os
 import tempfile
 
 def compress_pdf(input_file, url, quality):
-    if input_file is None and url is None:
+    if input_file is None and (url is None or url.strip() == ""):
         return None, "Please provide either a file or a URL."
     
-    if input_file is not None and url is not None:
+    if input_file is not None and url and url.strip() != "":
         return None, "Please provide either a file or a URL, not both."
     
-    if url:
+    if url and url.strip() != "":
         try:
             response = requests.get(url)
             response.raise_for_status()