opentelemetry-instrumentation-httpx: make instrument_client a staticmethod again (#3003)

* opentelemetry-instrumentation-httpx: make instrument_client a staticmethod again

* ADd changelog

* Can be a classmethod

---------

Co-authored-by: Leighton Chen <[email protected]>

Author: xrmx

CHANGELOG.md

@@ -20,6 +20,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- `opentelemetry-instrumentation-httpx`: instrument_client is a static method again
+  ([#3003](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3003))
+
 ### Breaking changes
 
 - `opentelemetry-instrumentation-sqlalchemy` teach instruments version

instrumentation/opentelemetry-instrumentation-httpx/src/opentelemetry/instrumentation/httpx/__init__.py

@@ -938,8 +938,9 @@ async def _handle_async_request_wrapper(  # pylint: disable=too-many-locals
 
         return response
 
+    @classmethod
     def instrument_client(
-        self,
+        cls,
         client: typing.Union[httpx.Client, httpx.AsyncClient],
         tracer_provider: TracerProvider = None,
         request_hook: typing.Union[
@@ -996,7 +997,7 @@ def instrument_client(
                 client._transport,
                 "handle_request",
                 partial(
-                    self._handle_request_wrapper,
+                    cls._handle_request_wrapper,
                     tracer=tracer,
                     sem_conv_opt_in_mode=sem_conv_opt_in_mode,
                     request_hook=request_hook,
@@ -1008,7 +1009,7 @@ def instrument_client(
                     transport,
                     "handle_request",
                     partial(
-                        self._handle_request_wrapper,
+                        cls._handle_request_wrapper,
                         tracer=tracer,
                         sem_conv_opt_in_mode=sem_conv_opt_in_mode,
                         request_hook=request_hook,
@@ -1021,7 +1022,7 @@ def instrument_client(
                 client._transport,
                 "handle_async_request",
                 partial(
-                    self._handle_async_request_wrapper,
+                    cls._handle_async_request_wrapper,
                     tracer=tracer,
                     sem_conv_opt_in_mode=sem_conv_opt_in_mode,
                     async_request_hook=async_request_hook,
@@ -1033,7 +1034,7 @@ def instrument_client(
                     transport,
                     "handle_async_request",
                     partial(
-                        self._handle_async_request_wrapper,
+                        cls._handle_async_request_wrapper,
                         tracer=tracer,
                         sem_conv_opt_in_mode=sem_conv_opt_in_mode,
                         async_request_hook=async_request_hook,

instrumentation/opentelemetry-instrumentation-httpx/tests/test_httpx_integration.py

@@ -910,13 +910,20 @@ def test_suppress_instrumentation_new_client(self):
 
             self.assert_span(num_spans=0)
 
-        def test_instrument_client(self):
+        def test_instrument_client_called_on_the_instance(self):
             client = self.create_client()
             HTTPXClientInstrumentor().instrument_client(client)
             result = self.perform_request(self.URL, client=client)
             self.assertEqual(result.text, "Hello!")
             self.assert_span(num_spans=1)
 
+        def test_instrument_client_called_on_the_class(self):
+            client = self.create_client()
+            HTTPXClientInstrumentor.instrument_client(client)
+            result = self.perform_request(self.URL, client=client)
+            self.assertEqual(result.text, "Hello!")
+            self.assert_span(num_spans=1)
+
         def test_instrumentation_without_client(self):
             HTTPXClientInstrumentor().instrument()
             results = [