fix(w3c trace context): correctly parse flags hex string to int

Signed-off-by: Bastian Krol <[email protected]>

Author: Bastian Krol

instana/w3c_trace_context/traceparent.py

@@ -36,12 +36,13 @@ def get_traceparent_fields(traceparent):
             version = traceparent_properties[0]
             trace_id = traceparent_properties[1]
             parent_id = traceparent_properties[2]
-            flags = int(traceparent_properties[3])
+            flags = int(traceparent_properties[3], 16)
             sampled_flag = (flags & SAMPLED_BITMASK) == SAMPLED_BITMASK
             return version, trace_id, parent_id, sampled_flag
-        except Exception:  # This method is intended to be called with a version 00 validated traceparent
+        except Exception as err:  # This method is intended to be called with a version 00 validated traceparent
             # This exception handling is added just for making sure we do not throw any unhandled exception
             # if somebody calls the method in the future without a validated traceparent
+            logger.debug("Parsing the traceparent failed: {}".format(err))
             return None, None, None, None
 
     def update_traceparent(self, traceparent, in_trace_id, in_span_id, level):

tests/w3c_trace_context/test_traceparent.py

@@ -13,6 +13,16 @@ def test_validate_valid(self):
         traceparent = "00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01"
         self.assertEqual(traceparent, self.tp.validate(traceparent))
 
+    def test_validate_newer_version(self):
+        # Although the incoming traceparent header sports a newer version number, we should still be able to parse the
+        # parts that we understand (and consider it valid).
+        traceparent = "ff-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01-12345-abcd"
+        self.assertEqual(traceparent, self.tp.validate(traceparent))
+
+    def test_validate_unknown_flags(self):
+        traceparent = "00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-ee"
+        self.assertEqual(traceparent, self.tp.validate(traceparent))
+
     def test_validate_invalid_traceparent(self):
         traceparent = "00-4bxxxxx3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01"
         self.assertIsNone(self.tp.validate(traceparent))
@@ -35,6 +45,22 @@ def test_get_traceparent_fields_unsampled(self):
         self.assertEqual(parent_id, "00f067aa0ba902b7")
         self.assertFalse(sampled_flag)
 
+    def test_get_traceparent_fields_newer_version(self):
+        # Although the incoming traceparent header sports a newer version number, we should still be able to parse the
+        # parts that we understand (and consider it valid).
+        traceparent = "ff-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01-12345-abcd"
+        version, trace_id, parent_id, sampled_flag = self.tp.get_traceparent_fields(traceparent)
+        self.assertEqual(trace_id, "4bf92f3577b34da6a3ce929d0e0e4736")
+        self.assertEqual(parent_id, "00f067aa0ba902b7")
+        self.assertTrue(sampled_flag)
+
+    def test_get_traceparent_fields_unknown_flags(self):
+        traceparent = "00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-ff"
+        version, trace_id, parent_id, sampled_flag = self.tp.get_traceparent_fields(traceparent)
+        self.assertEqual(trace_id, "4bf92f3577b34da6a3ce929d0e0e4736")
+        self.assertEqual(parent_id, "00f067aa0ba902b7")
+        self.assertTrue(sampled_flag)
+
     def test_get_traceparent_fields_None_input(self):
         traceparent = None
         version, trace_id, parent_id, sampled_flag = self.tp.get_traceparent_fields(traceparent)