certificate checking fix, and packaging changes.

fixes: #24

debian/changelog

+ligo-gracedb (2.7.2-1) unstable; urgency=low
+  * Bugfix for certificate check failure with tuple'd credentials
+
+ -- Alexander E. Pace <alexander.pace@ligo.org> Mon, 16 Nov 2020 21:03:38 +0000
+
 ligo-gracedb (2.7.1-1) unstable; urgency=low
   * Improved exception handling for HTTPErrors
   * Fix and deprecation warning for gracedb_legacy CLI tool

ligo-gracedb.spec

 %define name              ligo-gracedb
-%define version           2.7.1
-%define unmangled_version 2.7.1
+%define version           2.7.2
+%define unmangled_version 2.7.2
 %define release           1
 
 Summary:   Gravity Wave Candidate Event Database

ligo/gracedb/cert.py

@@ -39,7 +39,22 @@ far_future = datetime.timedelta(days=365)
 def load_certificate(cert):
     """ Loads in a path to a x509 certificate and returns a
         x509.cryptography object """
-    with open(cert, 'rb') as cert_obj:
+
+    # Check certificate type. First check if cert is a tuple, then
+    # take the first entry, which is assumed to be the cert.
+    # If it's a string, then take that. Otherwise fail.
+
+    if isinstance(cert, tuple):
+        cert_file = cert[0]
+    elif isinstance(cert, str):
+        cert_file = cert
+    else:
+        raise RuntimeError('Unknown certificate format. Certificate must '
+                           'be a tuple of format ("/path/to/cert",'
+                           '"/path/to/key") or a string or the path to the '
+                           'combined certificate/key')
+
+    with open(cert_file, 'rb') as cert_obj:
         cert_obj = cert_obj.read()
 
     # Try loading with PEM, then try loading with DER, then give up.
@@ -50,7 +65,7 @@ def load_certificate(cert):
         )
     except ValueError:
         try:
-            return x509.load_pem_x509_certificate(
+            return x509.load_der_x509_certificate(
                 cert_obj, default_backend()
             )
         except ValueError:

ligo/gracedb/version.py

-__version__ = '2.7.1'
+__version__ = '2.7.2'