Use environment variable NO_MBT_OTEL_CONFIG to skip configuring providers with the MBT

Author: Sam Eagen

instrumentation/buildtool/+matlab/+buildtool/+plugins/OpenTelemetryPlugin.m

@@ -132,6 +132,12 @@ function runTask(plugin, pluginData)
 
 % Use the same configuration as PADV
 function extcontextscope = configureOTel()
+
+% Skip configuration if NO_MBT_OTEL_CONFIG set
+if (getenv("NO_MBT_OTEL_CONFIG"))
+    return;
+end
+
 % populate resource attributes
 otelservicename = "buildtool";
 otelresource = dictionary("service.name", otelservicename);
@@ -174,6 +180,11 @@ function runTask(plugin, pluginData)
 % Use the same cleanup as PADV
 function cleanupOTel(span)
 
+% Skip cleanup if NO_MBT_OTEL_CONFIG set
+if (getenv("NO_MBT_OTEL_CONFIG"))
+    return;
+end
+
 timeout = 5;
 
 % end the input span before cleaning up

test/tbuildtoolplugin.m

@@ -522,6 +522,29 @@ function runningSeveralTasksProducesCorrectMetrics(testCase)
             testCase.verifyEqual(metrics(5).name, 'buildtool.tasks.successful');
             testCase.verifyEqual(metrics(5).sum.dataPoints.asDouble, 3);
         end
+
+        function buildToolDoesNotConfigureOTelWhenEnvVariableSet(testCase)
+            testCase.assumeFalse(isMATLABReleaseOlderThan("R2026a"));
+
+            % Restore environment variable
+            testCase.addTeardown(@()setenv("NO_MBT_OTEL_CONFIG", ""));
+
+            % Set environment variable
+            setenv("NO_MBT_OTEL_CONFIG", "1");
+
+            % Create plan with 1 successful task
+            plan = buildplan();
+            plan("task") = matlab.buildtool.Task();
+
+            % Run build
+            testCase.BuildRunner.run(plan, "task");
+
+            % Get results
+            results = readJsonResults(testCase);
+
+            % Verify results are empty since we never set up any providers
+            testCase.verifyEmpty(results);
+        end
     end
 end