instrumentation/pymongo: Cast PyMongo commands as strings (#1132)

Replacement PR for #1015

Author: alrex

instrumentation/opentelemetry-instrumentation-pymongo/CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+- Cast PyMongo commands as strings
+  ([#1132](https://github.com/open-telemetry/opentelemetry-python/pull/1132))
+
 ## Version 0.13b0
 
 Released 2020-09-17

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

@@ -66,8 +66,8 @@ def started(self, event: monitoring.CommandStartedEvent):
         name = DATABASE_TYPE + "." + event.command_name
         statement = event.command_name
         if command:
-            name += "." + command
-            statement += " " + command
+            name += "." + str(command)
+            statement += " " + str(command)
 
         try:
             span = self._tracer.start_span(name, kind=SpanKind.CLIENT)

instrumentation/opentelemetry-instrumentation-pymongo/tests/test_pymongo.py

@@ -138,6 +138,23 @@ def test_multiple_commands(self):
             trace_api.status.StatusCanonicalCode.UNKNOWN,
         )
 
+    def test_int_command(self):
+        command_attrs = {
+            "command_name": 123,
+        }
+        mock_event = MockEvent(command_attrs)
+
+        command_tracer = CommandTracer(self.tracer)
+        command_tracer.started(event=mock_event)
+        command_tracer.succeeded(event=mock_event)
+
+        spans_list = self.memory_exporter.get_finished_spans()
+
+        self.assertEqual(len(spans_list), 1)
+        span = spans_list[0]
+
+        self.assertEqual(span.name, "mongodb.command_name.123")
+
 
 class MockCommand:
     def __init__(self, command_attrs):