modify kafka context getter helper methods to work on dict and list

Author: mrajashree

instrumentation/opentelemetry-instrumentation-confluent-kafka/src/opentelemetry/instrumentation/confluent_kafka/utils.py

@@ -41,16 +41,26 @@ class KafkaContextGetter(textmap.Getter):
     def get(self, carrier: textmap.CarrierT, key: str) -> Optional[List[str]]:
         if carrier is None:
             return None
-        for item_key, value in carrier:
+
+        carrier_items = carrier
+        if isinstance(carrier, dict):
+            carrier_items = carrier.items()
+
+        for item_key, value in carrier_items:
             if item_key == key:
                 if value is not None:
                     return [value.decode()]
+
         return None
 
     def keys(self, carrier: textmap.CarrierT) -> List[str]:
         if carrier is None:
             return []
-        return [key for (key, value) in carrier]
+
+        carrier_items = carrier
+        if isinstance(carrier, dict):
+            carrier_items = carrier.items()
+        return [key for (key, value) in carrier_items]
 
 
 class KafkaContextSetter(textmap.Setter):

instrumentation/opentelemetry-instrumentation-confluent-kafka/tests/test_instrumentation.py

@@ -25,6 +25,7 @@
 )
 from opentelemetry.instrumentation.confluent_kafka.utils import (
     KafkaContextSetter,
+    KafkaContextGetter,
 )
 
 
@@ -89,3 +90,17 @@ def test_context_setter(self) -> None:
         carrier_list = [("key1", "val1")]
         context_setter.set(carrier_list, "key2", "val2")
         self.assertTrue(("key2", "val2".encode()) in carrier_list)
+
+    def test_context_getter(self) -> None:
+        context_setter = KafkaContextSetter()
+        context_getter = KafkaContextGetter()
+
+        carrier_dict = {}
+        context_setter.set(carrier_dict, "key1", "val1")
+        self.assertEqual(context_getter.get(carrier_dict, "key1"), ["val1"])
+        self.assertEqual(["key1"], context_getter.keys(carrier_dict))
+
+        carrier_list = []
+        context_setter.set(carrier_list, "key1", "val1")
+        self.assertEqual(context_getter.get(carrier_list, "key1"), ["val1"])
+        self.assertEqual(["key1"], context_getter.keys(carrier_list))