Accept TraceContext from host (#554)

* Set correlation id in context

* Modified context being passed from host.

* Updated parameters

* Testing build. (This will be reverted).

* Unit test failure.

* code quality unit test failure.

* Code quality unit test.

* Indentation fix

* Updated DOTNET_VERSION and runtime version.

* Modified test and addressed code review comments

* Updated test

* Testing

* Modified test

* removed space

* New line at end of file

Author: yojagad

azure_functions_worker/bindings/__init__.py

@@ -1,3 +1,4 @@
+from .tracecontext import TraceContext
 from .context import Context
 from .meta import check_input_type_annotation
 from .meta import check_output_type_annotation
@@ -10,5 +11,5 @@
     'Out', 'Context',
     'is_trigger_binding',
     'check_input_type_annotation', 'check_output_type_annotation',
-    'from_incoming_proto', 'to_outgoing_proto',
+    'from_incoming_proto', 'to_outgoing_proto', 'TraceContext',
 )

azure_functions_worker/bindings/context.py

@@ -1,10 +1,14 @@
+from . import TraceContext
+
+
 class Context:
 
     def __init__(self, func_name: str, func_dir: str,
-                 invocation_id: str) -> None:
+                 invocation_id: str, trace_context: TraceContext) -> None:
         self.__func_name = func_name
         self.__func_dir = func_dir
         self.__invocation_id = invocation_id
+        self.__trace_context = trace_context
 
     @property
     def invocation_id(self) -> str:
@@ -17,3 +21,7 @@ def function_name(self) -> str:
     @property
     def function_directory(self) -> str:
         return self.__func_dir
+
+    @property
+    def trace_context(self) -> TraceContext:
+        return self.__trace_context

azure_functions_worker/bindings/tracecontext.py

@@ -0,0 +1,19 @@
+class TraceContext:
+
+    def __init__(self, trace_parent: str,
+                 trace_state: str, attributes: dict) -> None:
+        self.__trace_parent = trace_parent
+        self.__trace_state = trace_state
+        self.__attributes = attributes
+
+    @property
+    def Tracestate(self) -> str:
+        return self.__trace_state
+
+    @property
+    def Traceparent(self) -> str:
+        return self.__trace_parent
+
+    @property
+    def Attributes(self) -> str:
+        return self.__attributes

azure_functions_worker/dispatcher.py

@@ -269,7 +269,10 @@ async def _handle__invocation_request(self, req):
 
         invocation_id = invoc_request.invocation_id
         function_id = invoc_request.function_id
-
+        trace_context = bindings.TraceContext(
+            invoc_request.trace_context.trace_parent,
+            invoc_request.trace_context.trace_state,
+            invoc_request.trace_context.attributes)
         # Set the current `invocation_id` to the current task so
         # that our logging handler can find it.
         current_task = asyncio.Task.current_task(self._loop)
@@ -298,7 +301,7 @@ async def _handle__invocation_request(self, req):
 
             if fi.requires_context:
                 args['context'] = bindings.Context(
-                    fi.name, fi.directory, invocation_id)
+                    fi.name, fi.directory, invocation_id, trace_context)
 
             if fi.output_types:
                 for name in fi.output_types:

tests/unittests/http_functions/return_context/main.py

@@ -9,4 +9,6 @@ def main(req: azure.functions.HttpRequest, context: azure.functions.Context):
         'ctx_func_name': context.function_name,
         'ctx_func_dir': context.function_directory,
         'ctx_invocation_id': context.invocation_id,
+        'ctx_trace_context_Traceparent': context.trace_context.Traceparent,
+        'ctx_trace_context_Tracestate': context.trace_context.Tracestate,
     })

tests/unittests/test_http_functions.py

@@ -104,6 +104,8 @@ def test_return_context(self):
         self.assertEqual(data['ctx_func_name'], 'return_context')
         self.assertIn('return_context', data['ctx_func_dir'])
         self.assertIn('ctx_invocation_id', data)
+        self.assertIn('ctx_trace_context_Tracestate', data)
+        self.assertIn('ctx_trace_context_Traceparent', data)
 
     def test_remapped_context(self):
         r = self.webhost.request('GET', 'remapped_context')