Update gettracer (#1854)

Author: eddyleelin

CHANGELOG.md

@@ -6,6 +6,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased](https://github.com/open-telemetry/opentelemetry-python/compare/v1.2.0-0.21b0...HEAD)
 
+### Changed
+- Updated get_tracer to return an empty string when passed an invalid name
+  ([#1854](https://github.com/open-telemetry/opentelemetry-python/pull/1854))
+
 ## [1.2.0, 0.21b0](https://github.com/open-telemetry/opentelemetry-python/releases/tag/v1.2.0-0.21b0) - 2021-05-11
 
 ### Added

opentelemetry-sdk/src/opentelemetry/sdk/trace/__init__.py

@@ -997,7 +997,7 @@ def get_tracer(
         instrumenting_library_version: str = "",
     ) -> "trace_api.Tracer":
         if not instrumenting_module_name:  # Reject empty strings too.
-            instrumenting_module_name = "ERROR:MISSING MODULE NAME"
+            instrumenting_module_name = ""
             logger.error("get_tracer called with missing module name.")
         return Tracer(
             self.sampler,

opentelemetry-sdk/tests/trace/test_trace.py

@@ -257,17 +257,25 @@ def test_invalid_instrumentation_info(self):
             tracer1 = tracer_provider.get_tracer("")
         with self.assertLogs(level=ERROR):
             tracer2 = tracer_provider.get_tracer(None)
-        self.assertEqual(
-            tracer1.instrumentation_info, tracer2.instrumentation_info
-        )
+
         self.assertIsInstance(
             tracer1.instrumentation_info, InstrumentationInfo
         )
         span1 = tracer1.start_span("foo")
         self.assertTrue(span1.is_recording())
         self.assertEqual(tracer1.instrumentation_info.version, "")
+        self.assertEqual(tracer1.instrumentation_info.name, "")
+
+        self.assertIsInstance(
+            tracer2.instrumentation_info, InstrumentationInfo
+        )
+        span2 = tracer2.start_span("bar")
+        self.assertTrue(span2.is_recording())
+        self.assertEqual(tracer2.instrumentation_info.version, "")
+        self.assertEqual(tracer2.instrumentation_info.name, "")
+
         self.assertEqual(
-            tracer1.instrumentation_info.name, "ERROR:MISSING MODULE NAME"
+            tracer1.instrumentation_info, tracer2.instrumentation_info
         )
 
     def test_span_processor_for_source(self):