fix otlp grpc exporter bug when no scheme is passed in (open-telemetry#1806)

Author: alrex

CHANGELOG.md

@@ -7,11 +7,15 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased](https://github.com/open-telemetry/opentelemetry-python/compare/v1.1.0...HEAD)
 
 ### Added
-- Added example for running Django with auto instrumentation
+- Added example for running Django with auto instrumentation.
   ([#1803](https://github.com/open-telemetry/opentelemetry-python/pull/1803))
 
+### Changed
+- Fixed OTLP gRPC exporter silently failing if scheme is not specified in endpoint.
+  ([#1806](https://github.com/open-telemetry/opentelemetry-python/pull/1806))
+
 ### Removed
-- Moved `opentelemetry-instrumentation` to contrib repository
+- Moved `opentelemetry-instrumentation` to contrib repository.
   ([#1797](https://github.com/open-telemetry/opentelemetry-python/pull/1797))
 
 ## [1.1.0](https://github.com/open-telemetry/opentelemetry-python/releases/tag/v1.1.0) - 2021-04-20

exporter/opentelemetry-exporter-otlp-proto-grpc/src/opentelemetry/exporter/otlp/proto/grpc/exporter.py

@@ -207,7 +207,8 @@ def __init__(
             else:
                 insecure = True
 
-        endpoint = parsed_url.netloc
+        if parsed_url.netloc:
+            endpoint = parsed_url.netloc
 
         self._headers = headers or environ.get(OTEL_EXPORTER_OTLP_HEADERS)
         if isinstance(self._headers, str):

exporter/opentelemetry-exporter-otlp-proto-grpc/tests/test_otlp_trace_exporter.py

@@ -239,6 +239,7 @@ def test_otlp_headers_from_env(self, mock_ssl_channel, mock_secure):
     @patch("opentelemetry.exporter.otlp.proto.grpc.exporter.secure_channel")
     def test_otlp_exporter_endpoint(self, mock_secure, mock_insecure):
         """Just OTEL_EXPORTER_OTLP_COMPRESSION should work"""
+        expected_endpoint = "localhost:4317"
         endpoints = [
             (
                 "http://localhost:4317",
@@ -275,6 +276,13 @@ def test_otlp_exporter_endpoint(self, mock_secure, mock_insecure):
                     mock_method, endpoint, insecure
                 ),
             )
+            self.assertEqual(
+                expected_endpoint,
+                mock_method.call_args[0][0],
+                "expected {} got {} {}".format(
+                    expected_endpoint, mock_method.call_args[0][0], endpoint
+                ),
+            )
             mock_method.reset_mock()
 
     # pylint: disable=no-self-use