botocore: Fix uninstrument to also unpatch header injection on Endpoint

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased](https://github.com/open-telemetry/opentelemetry-python/compare/v1.5.0-0.24b0...HEAD)
 
+### Changed
+- `opentelemetry-instrumentation-botocore` Unpatch botocore Endpoint.prepare_request on uninstrument
+  ([#664](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/664))
+
 ## [1.5.0-0.24b0](https://github.com/open-telemetry/opentelemetry-python/releases/tag/v1.5.0-0.24b0) - 2021-08-26
 
 ### Added

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

@@ -51,6 +51,7 @@
 from typing import Collection
 
 from botocore.client import BaseClient
+from botocore.endpoint import Endpoint
 from botocore.exceptions import ClientError
 from wrapt import wrap_function_wrapper
 
@@ -114,6 +115,7 @@ def _instrument(self, **kwargs):
 
     def _uninstrument(self, **kwargs):
         unwrap(BaseClient, "_make_api_call")
+        unwrap(Endpoint, "prepare_request")
 
     @staticmethod
     def _is_lambda_invoke(service_name, operation_name, api_params):

instrumentation/opentelemetry-instrumentation-botocore/tests/test_botocore_instrumentation.py

@@ -61,6 +61,7 @@ def lambda_handler(event, context):
     return pfunc
 
 
+# pylint:disable=too-many-public-methods
 class TestBotocoreInstrumentor(TestBase):
     """Botocore integration testsuite"""
 
@@ -322,6 +323,31 @@ def test_unpatch(self):
         spans = self.memory_exporter.get_finished_spans()
         assert not spans, spans
 
+    @mock_ec2
+    def test_uninstrument_does_not_inject_headers(self):
+        headers = {}
+        previous_propagator = get_global_textmap()
+        try:
+            set_global_textmap(MockTextMapPropagator())
+
+            def intercept_headers(**kwargs):
+                headers.update(kwargs["request"].headers)
+
+            ec2 = self.session.create_client("ec2", region_name="us-west-2")
+
+            BotocoreInstrumentor().uninstrument()
+
+            ec2.meta.events.register_first(
+                "before-send.ec2.DescribeInstances", intercept_headers
+            )
+            with self.tracer_provider.get_tracer("test").start_span("parent"):
+                ec2.describe_instances()
+
+            self.assertNotIn(MockTextMapPropagator.TRACE_ID_KEY, headers)
+            self.assertNotIn(MockTextMapPropagator.SPAN_ID_KEY, headers)
+        finally:
+            set_global_textmap(previous_propagator)
+
     @mock_sqs
     def test_double_patch(self):
         sqs = self.session.create_client("sqs", region_name="us-east-1")