fix: One more check

Author: tmathern

src/c2pa/c2pa.py

@@ -245,6 +245,17 @@ def __init__(self, alg=None, sign_cert=None, private_key=None, ta_url=None):
         else:
             alg = None
 
+        # Handle ta_url parameter - convert string to bytes if needed
+        if ta_url is not None:
+            if isinstance(ta_url, str):
+                # Convert string to bytes
+                ta_url = ta_url.encode('utf-8')
+            elif isinstance(ta_url, bytes):
+                # Already in bytes format
+                pass
+            else:
+                raise TypeError(f"ta_url must be string or bytes, got {type(ta_url)}")
+
         # Call parent constructor with processed values
         super().__init__(alg, sign_cert, private_key, ta_url)
 

tests/test_unit_tests.py

@@ -1409,7 +1409,7 @@ def test_sign_file_alg_as_enum(self):
             alg=SigningAlg.ES256,
             sign_cert=certs,
             private_key=key,
-            ta_url=b"http://timestamp.digicert.com"
+            ta_url="http://timestamp.digicert.com"
         )
 
         # Create a simple manifest