Fix for byte type attributes crashing spans

opentelemetry-sdk/CHANGELOG.md

@@ -6,6 +6,8 @@
   ([#751](https://github.com/open-telemetry/opentelemetry-python/pull/751))
 - Rename Measure to ValueRecorder in metrics
   ([#761](https://github.com/open-telemetry/opentelemetry-python/pull/761))
+- bugfix: byte type attributes are decoded before adding to attributes dict
+  ([#775](https://github.com/open-telemetry/opentelemetry-python/pull/775))
 
 ## 0.8b0
 

opentelemetry-sdk/src/opentelemetry/sdk/trace/__init__.py

@@ -424,6 +424,12 @@ def set_attribute(self, key: str, value: types.AttributeValue) -> None:
             # Freeze mutable sequences defensively
             if isinstance(value, MutableSequence):
                 value = tuple(value)
+            if isinstance(value, bytes):
+                try:
+                    value = value.decode()
+                except ValueError:
+                    logger.warning("Byte attribute could not be decoded.")
+                    return
             with self._lock:
                 self.attributes[key] = value
 

opentelemetry-sdk/tests/trace/test_trace.py

@@ -487,6 +487,15 @@ def test_invalid_attribute_values(self):
 
             self.assertEqual(len(root.attributes), 0)
 
+    def test_byte_type_attribute_value(self):
+        with self.tracer.start_as_current_span("root") as root:
+            with self.assertLogs(level=WARNING):
+                root.set_attribute("invalid-byte-type-attribute", b"\xd8\xe1\xb7\xeb\xa8\xe5 \xd2\xb7\xe1")
+                self.assertFalse("invalid-byte-type-attribute" in root.attributes)
+
+            root.set_attribute("valid-byte-type-attribute", b"valid byte")
+            self.assertTrue(isinstance(root.attributes["valid-byte-type-attribute"], str))
+
     def test_check_attribute_helper(self):
         # pylint: disable=protected-access
         self.assertFalse(trace._is_valid_attribute_value([1, 2, 3.4, "ss", 4]))