Update certificates.py

Author: venkatamutyala

glueops/certificates.py

@@ -1,15 +1,24 @@
 from cryptography import x509
 from cryptography.hazmat.backends import default_backend
+from cryptography.exceptions import UnsupportedAlgorithm, InvalidSignature
 
 
 def extract_serial_number_from_cert_string(cert_string):
-    certificate = x509.load_pem_x509_certificate(cert_string.encode(), default_backend())
-    decimal_serial = certificate.serial_number
-    # Convert to hexadecimal
-    hex_serial = format(decimal_serial, 'X')
-    # Ensure an even number of digits for correct byte representation
-    if len(hex_serial) % 2 != 0:
-        hex_serial = '0' + hex_serial
-    # Insert colons between every 2 characters
-    colon_separated_serial = ":".join(hex_serial[i:i+2] for i in range(0, len(hex_serial), 2))
-    return colon_separated_serial
+    try:
+        certificate = x509.load_pem_x509_certificate(cert_string.encode(), default_backend())
+        decimal_serial = certificate.serial_number
+        
+        # Convert to hexadecimal
+        hex_serial = format(decimal_serial, 'X')
+        
+        # Ensure an even number of digits for correct byte representation
+        if len(hex_serial) % 2 != 0:
+            hex_serial = '0' + hex_serial
+        
+        # Insert colons between every 2 characters
+        colon_separated_serial = ":".join(hex_serial[i:i+2] for i in range(0, len(hex_serial), 2))
+        return colon_separated_serial
+
+    except (ValueError, UnsupportedAlgorithm, InvalidSignature) as e:
+        # You can specify more exceptions as needed based on the specific errors you're encountering.
+        raise ValueError("Provided certificate string is not parsable: " + str(e))