feat: configure trace level

src/main/java/com/vaadin/extension/Constants.java

@@ -0,0 +1,9 @@
+package com.vaadin.extension;
+
+/**
+ * Constants used by the Vaadin observability extension, for example for
+ * configuration options
+ */
+public class Constants {
+    public static final String CONFIG_TRACE_LEVEL = "otel.instrumentation.vaadin.trace-level";
+}

src/main/java/com/vaadin/extension/conf/Configuration.java

@@ -0,0 +1,34 @@
+package com.vaadin.extension.conf;
+
+import com.vaadin.extension.Constants;
+
+import io.opentelemetry.javaagent.bootstrap.internal.InstrumentationConfig;
+
+/**
+ * Provides the effective configuration for the Vaadin observability extension.
+ */
+public class Configuration {
+    public static final TraceLevel TRACE_LEVEL = determineTraceLevel();
+
+    private static TraceLevel determineTraceLevel() {
+        String traceLevelString = InstrumentationConfig.get().getString(
+                Constants.CONFIG_TRACE_LEVEL, TraceLevel.DEFAULT.name());
+        try {
+            return TraceLevel.valueOf(traceLevelString.toUpperCase());
+        } catch (IllegalArgumentException ignored) {
+            return TraceLevel.DEFAULT;
+        }
+    }
+
+    /**
+     * Checks whether a trace level is enabled. Can be used by instrumentations
+     * to check whether some detail should be added to a trace or not.
+     *
+     * @param traceLevel
+     *            the trace level to check
+     * @return true if the trace level is enabled, false if not
+     */
+    public static boolean isEnabled(TraceLevel traceLevel) {
+        return TRACE_LEVEL.includes(traceLevel);
+    }
+}

src/main/java/com/vaadin/extension/Configuration.java → src/main/java/com/vaadin/extension/conf/ConfigurationDefaults.java

@@ -1,4 +1,6 @@
-package com.vaadin.extension;
+package com.vaadin.extension.conf;
+
+import com.vaadin.extension.Constants;
 
 import com.google.auto.service.AutoService;
 import io.opentelemetry.javaagent.extension.config.ConfigPropertySource;
@@ -7,8 +9,9 @@
 import java.util.Map;
 
 /**
- * disable the automatic vaadin instrumentation Custom distributions can supply
- * their own default configuration by implementing {@link ConfigPropertySource}.
+ * Provides default values for global and extension-specific OpenTelemetry
+ * configuration. The defaults can be overwritten by a configuration mechanism
+ * with a higher priority.
  *
  * <p>
  * The configuration priority, from highest to lowest is:
@@ -22,7 +25,7 @@
  * </ul>
  */
 @AutoService(ConfigPropertySource.class)
-public class Configuration implements ConfigPropertySource {
+public class ConfigurationDefaults implements ConfigPropertySource {
 
     @Override
     public Map<String, String> getProperties() {
@@ -31,6 +34,8 @@ public Map<String, String> getProperties() {
         properties.put("otel.instrumentation.vaadin.enabled", "false");
         // Set the service name to vaadin by default.
         properties.put("otel.service.name", "vaadin");
+        // Configure default trace level
+        properties.put(Constants.CONFIG_TRACE_LEVEL, TraceLevel.DEFAULT.name());
         return properties;
     }
 }

src/main/java/com/vaadin/extension/conf/TraceLevel.java

@@ -0,0 +1,14 @@
+package com.vaadin.extension.conf;
+
+/**
+ * The detail level of traces. The global trace level can be configured in the
+ * {@link Configuration}, and individual instrumentations can check the trace
+ * level to determine whether to add something to a trace or not.
+ */
+public enum TraceLevel {
+    MINIMUM, DEFAULT, MAXIMUM,;
+
+    public boolean includes(TraceLevel level) {
+        return this.ordinal() >= level.ordinal();
+    }
+}

src/main/java/com/vaadin/extension/instrumentation/UidlRequestHandlerInstrumentation.java

@@ -5,7 +5,8 @@
 import static net.bytebuddy.matcher.ElementMatchers.named;
 
 import com.vaadin.extension.InstrumentationHelper;
-import com.vaadin.flow.server.communication.UidlRequestHandler;
+import com.vaadin.extension.conf.Configuration;
+import com.vaadin.extension.conf.TraceLevel;
 
 import io.opentelemetry.api.trace.Span;
 import io.opentelemetry.context.Context;
@@ -42,17 +43,15 @@ public void transform(TypeTransformer transformer) {
     public static class SynchronizedHandleRequestAdvice {
 
         @Advice.OnMethodEnter(suppress = Throwable.class)
-        public static void onEnter(
-                @Advice.This UidlRequestHandler uidlRequestHandler,
-                @Advice.Origin("#m") String methodName,
-                @Advice.Local("otelSpan") Span span,
+        public static void onEnter(@Advice.Local("otelSpan") Span span,
                 @Advice.Local("otelScope") Scope scope) {
-            String spanName = uidlRequestHandler.getClass().getSimpleName()
-                    + "." + methodName;
-            span = InstrumentationHelper.startSpan(spanName);
+            if (Configuration.isEnabled(TraceLevel.DEFAULT)) {
+                final String spanName = "Handle Client Request";
+                span = InstrumentationHelper.startSpan(spanName);
 
-            Context context = currentContext().with(span);
-            scope = context.makeCurrent();
+                Context context = currentContext().with(span);
+                scope = context.makeCurrent();
+            }
         }
 
         @Advice.OnMethodExit(onThrowable = Throwable.class, suppress = Throwable.class)

src/test/java/com/vaadin/extension/instrumentation/AbstractInstrumentationTest.java

@@ -3,6 +3,8 @@
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
 import com.vaadin.extension.ContextKeys;
+import com.vaadin.extension.conf.Configuration;
+import com.vaadin.extension.conf.TraceLevel;
 import com.vaadin.extension.instrumentation.util.MockVaadinService;
 import com.vaadin.extension.instrumentation.util.OpenTelemetryTestTools;
 import com.vaadin.flow.component.Component;
@@ -25,6 +27,7 @@
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.BeforeEach;
+import org.mockito.MockedStatic;
 import org.mockito.Mockito;
 
 import java.util.ArrayList;
@@ -35,6 +38,8 @@ public abstract class AbstractInstrumentationTest {
     private VaadinSession mockSession;
     private VaadinService mockService;
     private Scope sessionScope;
+    private MockedStatic<Configuration> ConfigurationMock;
+    private TraceLevel configuredTraceLevel;
 
     public UI getMockUI() {
         return mockUI;
@@ -87,11 +92,27 @@ public void openSessionContext() {
                 .with(ContextKeys.SESSION_ID, getMockSessionId()).makeCurrent();
     }
 
+    @BeforeEach
+    public void setupConfigurationMock() {
+        configuredTraceLevel = TraceLevel.DEFAULT;
+        ConfigurationMock = Mockito.mockStatic(Configuration.class);
+        ConfigurationMock.when(() -> Configuration.isEnabled(Mockito.any()))
+                .thenAnswer(invocation -> {
+                    TraceLevel level = invocation.getArgument(0);
+                    return configuredTraceLevel.includes(level);
+                });
+    }
+
     @AfterEach
     public void closeSessionContext() {
         sessionScope.close();
     }
 
+    @AfterEach
+    public void closeConfigurationMock() {
+        ConfigurationMock.close();
+    }
+
     protected RootContextScope withRootContext() {
         return new RootContextScope();
     }
@@ -100,6 +121,10 @@ protected Span getCapturedSpan(int index) {
         return OpenTelemetryTestTools.getSpanBuilderCapture().getSpan(index);
     }
 
+    protected int getCapturedSpanCount() {
+        return OpenTelemetryTestTools.getSpanBuilderCapture().getSpans().size();
+    }
+
     protected SpanData getExportedSpan(int index) {
         return OpenTelemetryTestTools.getSpanExporter().getSpan(index);
     }
@@ -120,6 +145,10 @@ protected void assertSpanHasException(SpanData span, Throwable throwable) {
                 .get(SemanticAttributes.EXCEPTION_MESSAGE));
     }
 
+    protected void configureTraceLevel(TraceLevel level) {
+        configuredTraceLevel = level;
+    }
+
     @Tag("test-view")
     protected static class TestView extends Component {
     }

src/test/java/com/vaadin/extension/instrumentation/UidlRequestHandlerInstrumentationTest.java

@@ -2,28 +2,42 @@
 
 import static org.junit.jupiter.api.Assertions.*;
 
-import com.vaadin.flow.server.communication.UidlRequestHandler;
+import com.vaadin.extension.conf.TraceLevel;
 
 import io.opentelemetry.sdk.trace.data.SpanData;
 import org.junit.jupiter.api.Test;
-import org.mockito.Mockito;
 
 class UidlRequestHandlerInstrumentationTest
         extends AbstractInstrumentationTest {
 
     @Test
     public void synchronizedHandleRequest_createsSpan() {
-        UidlRequestHandler uidlRequestHandler = Mockito
-                .mock(UidlRequestHandler.class);
-
         UidlRequestHandlerInstrumentation.SynchronizedHandleRequestAdvice
-                .onEnter(uidlRequestHandler, "synchronizedHandleRequest", null,
-                        null);
+                .onEnter(null, null);
         UidlRequestHandlerInstrumentation.SynchronizedHandleRequestAdvice
                 .onExit(null, getCapturedSpan(0), null);
 
         SpanData span = getExportedSpan(0);
-        assertEquals("UidlRequestHandler.synchronizedHandleRequest",
-                span.getName());
+        assertEquals("Handle Client Request", span.getName());
+    }
+
+    @Test
+    public void synchronizedHandleRequest_traceLevels() {
+        configureTraceLevel(TraceLevel.MINIMUM);
+        UidlRequestHandlerInstrumentation.SynchronizedHandleRequestAdvice
+                .onEnter(null, null);
+        assertEquals(0, getCapturedSpanCount());
+
+        configureTraceLevel(TraceLevel.DEFAULT);
+        resetSpans();
+        UidlRequestHandlerInstrumentation.SynchronizedHandleRequestAdvice
+                .onEnter(null, null);
+        assertEquals(1, getCapturedSpanCount());
+
+        configureTraceLevel(TraceLevel.MAXIMUM);
+        resetSpans();
+        UidlRequestHandlerInstrumentation.SynchronizedHandleRequestAdvice
+                .onEnter(null, null);
+        assertEquals(1, getCapturedSpanCount());
     }
 }