Added missing tests for parameter handling

micrometer-observation/src/test/java/io/micrometer/observation/aop/HighCardinality.java

@@ -0,0 +1,53 @@
+/**
+ * Copyright 2022 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.micrometer.observation.aop;
+
+import io.micrometer.common.annotation.NoOpValueResolver;
+import io.micrometer.common.annotation.ValueResolver;
+
+import java.lang.annotation.*;
+
+@Retention(RetentionPolicy.RUNTIME)
+@Inherited
+@Target(ElementType.PARAMETER)
+@interface HighCardinality {
+
+    /**
+     * The name of the key of the tag which should be created.
+     * @return the tag key
+     */
+    String value() default "";
+
+    /**
+     * The name of the key of the tag which should be created.
+     * @return the tag value
+     */
+    String key() default "";
+
+    /**
+     * Execute this expression to calculate the tag value. Will be analyzed if no value of
+     * the {@link HighCardinality#resolver()} was set.
+     * @return an expression
+     */
+    String expression() default "";
+
+    /**
+     * Use this bean to resolve the tag value. Has the highest precedence.
+     * @return {@link ValueResolver} bean
+     */
+    Class<? extends ValueResolver> resolver() default NoOpValueResolver.class;
+
+}

micrometer-observation/src/test/java/io/micrometer/observation/aop/HighCardinalityAnnotationHandler.java

@@ -0,0 +1,70 @@
+/*
+ * Copyright 2023 VMware, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.micrometer.observation.aop;
+
+import io.micrometer.common.KeyValue;
+import io.micrometer.common.annotation.AnnotationHandler;
+import io.micrometer.common.annotation.NoOpValueResolver;
+import io.micrometer.common.annotation.ValueExpressionResolver;
+import io.micrometer.common.annotation.ValueResolver;
+import io.micrometer.common.util.StringUtils;
+
+import io.micrometer.observation.Observation;
+
+import java.util.function.Function;
+
+/**
+ * Taken from Tracing for testing.
+ */
+class HighCardinalityAnnotationHandler extends AnnotationHandler<Observation> {
+
+    public HighCardinalityAnnotationHandler(
+            Function<Class<? extends ValueResolver>, ? extends ValueResolver> resolverProvider,
+            Function<Class<? extends ValueExpressionResolver>, ? extends ValueExpressionResolver> expressionResolverProvider) {
+        super((keyValue, observation) -> observation.highCardinalityKeyValue(keyValue), resolverProvider,
+                expressionResolverProvider, HighCardinality.class, (annotation, o) -> {
+                    if (!(annotation instanceof HighCardinality)) {
+                        return null;
+                    }
+                    HighCardinality highCardinality = (HighCardinality) annotation;
+                    return KeyValue.of(resolveTagKey(highCardinality),
+                            resolveTagValue(highCardinality, o, resolverProvider, expressionResolverProvider));
+                });
+    }
+
+    private static String resolveTagKey(HighCardinality annotation) {
+        return StringUtils.isNotBlank(annotation.value()) ? annotation.value() : annotation.key();
+    }
+
+    static String resolveTagValue(HighCardinality annotation, Object argument,
+            Function<Class<? extends ValueResolver>, ? extends ValueResolver> resolverProvider,
+            Function<Class<? extends ValueExpressionResolver>, ? extends ValueExpressionResolver> expressionResolverProvider) {
+        String value = null;
+        if (annotation.resolver() != NoOpValueResolver.class) {
+            ValueResolver ValueResolver = resolverProvider.apply(annotation.resolver());
+            value = ValueResolver.resolve(argument);
+        }
+        else if (StringUtils.isNotBlank(annotation.expression())) {
+            value = expressionResolverProvider.apply(ValueExpressionResolver.class)
+                .resolve(annotation.expression(), argument);
+        }
+        else if (argument != null) {
+            value = argument.toString();
+        }
+        return value == null ? "" : value;
+    }
+
+}

micrometer-observation/src/test/java/io/micrometer/observation/aop/ObservedAspectTests.java

@@ -23,11 +23,15 @@
 import io.micrometer.context.ContextSnapshotFactory;
 import io.micrometer.observation.Observation;
 import io.micrometer.observation.ObservationConvention;
+import io.micrometer.observation.ObservationRegistry;
 import io.micrometer.observation.ObservationTextPublisher;
 import io.micrometer.observation.annotation.Observed;
 import io.micrometer.observation.tck.TestObservationRegistry;
 import io.micrometer.observation.tck.TestObservationRegistryAssert;
+
 import org.aspectj.lang.ProceedingJoinPoint;
+import org.aspectj.lang.annotation.Around;
+import org.aspectj.lang.annotation.Aspect;
 import org.junit.jupiter.api.Test;
 import org.springframework.aop.aspectj.annotation.AspectJProxyFactory;
 
@@ -70,6 +74,27 @@ void annotatedCallShouldBeObserved() {
             .doesNotHaveError();
     }
 
+    @Test
+    void annotatedCallOnAnInterfaceObserved() {
+        registry.observationConfig().observationHandler(new ObservationTextPublisher());
+
+        AspectJProxyFactory pf = new AspectJProxyFactory(new TestBean());
+        pf.addAspect(new ObservedAspect(registry));
+        pf.addAspect(new AspectWithParameterHandler());
+
+        TestBeanInterface service = pf.getProxy();
+        service.testMethod("bar");
+
+        TestObservationRegistryAssert.assertThat(registry)
+            .doesNotHaveAnyRemainingCurrentObservation()
+            .hasSingleObservationThat()
+            .hasBeenStopped()
+            .hasNameEqualTo("test.method")
+            .hasContextualNameEqualTo("foo")
+            .hasHighCardinalityKeyValue("foo", "bar")
+            .doesNotHaveError();
+    }
+
     @Test
     void annotatedCallShouldBeObservedAndErrorRecorded() {
         registry.observationConfig().observationHandler(new ObservationTextPublisher());
@@ -363,6 +388,38 @@ CompletableFuture<String> async(FakeAsyncTask fakeAsyncTask) {
 
     }
 
+    interface TestBeanInterface {
+
+        @Observed(name = "test.method", contextualName = "foo")
+        default void testMethod(@HighCardinality(key = "foo") String foo) {
+
+        }
+
+    }
+
+    // Example of an implementation class
+    static class TestBean implements TestBeanInterface {
+
+    }
+
+    @Aspect
+    static class AspectWithParameterHandler {
+
+        private final HighCardinalityAnnotationHandler handler = new HighCardinalityAnnotationHandler(
+                aClass -> parameter -> "", aClass -> (expression, parameter) -> "");
+
+        private final ObservationRegistry observationRegistry = ObservationRegistry.create();
+
+        @Around("execution (@io.micrometer.observation.annotation.Observed * *.*(..))")
+        @Nullable
+        public Object observeMethod(ProceedingJoinPoint pjp) throws Throwable {
+            Observation observation = observationRegistry.getCurrentObservation();
+            handler.addAnnotatedParameters(observation, pjp);
+            return pjp.proceed();
+        }
+
+    }
+
     @Observed(name = "test.class", contextualName = "test.class#call",
             lowCardinalityKeyValues = { "abc", "123", "test", "42" })
     static class ObservedClassLevelAnnotatedService {