BAEL-5867: Micrometer Observability API with Spring Boot 3 (#13180)

* BAEL-5867: Create project and create first usage main method * BAEL-5867: Use Observation API in Boot * BAEL-5867: Refactoring and testing * BAEL-5867: Add tracing * BAEL-5867: Remove notes and add project as a module to the aggregator * BAEL-5867: Fix pmd rules violation
2022-12-28 21:47:49 +01:00
parent ab892ba982
commit 40249f907c
16 changed files with 481 additions and 0 deletions
@@ -0,0 +1,13 @@
+package com.baeldung.samples;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class GreetingApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(GreetingApplication.class, args);
+    }
+
+}
@@ -0,0 +1,66 @@
+package com.baeldung.samples;
+
+import io.micrometer.core.instrument.Measurement;
+import io.micrometer.core.instrument.Statistic;
+import io.micrometer.core.instrument.observation.DefaultMeterObservationHandler;
+import io.micrometer.core.instrument.simple.SimpleMeterRegistry;
+import io.micrometer.observation.Observation;
+import io.micrometer.observation.ObservationRegistry;
+import io.micrometer.observation.ObservationTextPublisher;
+
+import java.util.Optional;
+import java.util.stream.StreamSupport;
+
+public class SimpleObservationApplication {
+
+    // we can run this as a simple command line application
+    public static void main(String[] args) {
+        // create registry
+        final var observationRegistry = ObservationRegistry.create();
+        // create meter registry and observation handler
+        final var meterRegistry = new SimpleMeterRegistry();
+        final var meterObservationHandler = new DefaultMeterObservationHandler(meterRegistry);
+        // create simple logging observation handler
+        final var loggingObservationHandler = new ObservationTextPublisher(System.out::println);
+        // register observation handlers
+        observationRegistry
+          .observationConfig()
+          .observationHandler(meterObservationHandler)
+          .observationHandler(loggingObservationHandler);
+        // make an observation
+        Observation.Context context = new Observation.Context();
+        String observationName = "obs1";
+        Observation observation = Observation
+          .createNotStarted(observationName, () -> context, observationRegistry)
+          .lowCardinalityKeyValue("gender", "male")
+          .highCardinalityKeyValue("age", "41");
+
+        for (int i = 0; i < 10; i++) {
+            observation.observe(SimpleObservationApplication::doSomeAction);
+        }
+
+        meterRegistry.getMeters().forEach(m -> {
+            System.out.println(m.getId() + "\n============");
+            m.measure().forEach(ms -> System.out.println(ms.getValue() + " [" + ms.getStatistic() + "]"));
+            System.out.println("----------------------------");
+        });
+        Optional<Double> maximumDuration = meterRegistry.getMeters().stream()
+          .filter(m -> "obs1".equals(m.getId().getName()))
+          .flatMap(m -> StreamSupport.stream(m.measure().spliterator(), false))
+          .filter(ms -> ms.getStatistic() == Statistic.MAX)
+          .findFirst()
+          .map(Measurement::getValue);
+
+        System.out.println(maximumDuration);
+    }
+
+    private static void doSomeAction() {
+        try {
+            Thread.sleep(Math.round(Math.random() * 1000));
+            System.out.println("Hello World!");
+        } catch (InterruptedException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+}
@@ -0,0 +1,26 @@
+package com.baeldung.samples.boundary;
+
+import com.baeldung.samples.domain.GreetingService;
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.ResponseBody;
+
+@Controller
+@RequestMapping("/greet")
+public class GreetingController {
+
+    private final GreetingService service;
+
+    public GreetingController(GreetingService service) {
+        this.service = service;
+    }
+
+    @GetMapping(produces = MediaType.TEXT_PLAIN_VALUE)
+    @ResponseBody
+    public String sayHello() {
+        return this.service.sayHello();
+    }
+
+}
@@ -0,0 +1,22 @@
+package com.baeldung.samples.boundary;
+
+import io.micrometer.observation.ObservationRegistry;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.web.filter.ServerHttpObservationFilter;
+
+@Configuration
+public class ObservationFilterConfiguration {
+
+    // if an ObservationRegistry is already configured
+    @ConditionalOnBean(ObservationRegistry.class)
+    // if we do not use Actuator
+    @ConditionalOnMissingBean(ServerHttpObservationFilter.class)
+    @Bean
+    public ServerHttpObservationFilter observationFilter(ObservationRegistry registry) {
+        return new ServerHttpObservationFilter(registry);
+    }
+
+}
@@ -0,0 +1,28 @@
+package com.baeldung.samples.config;
+
+import io.micrometer.observation.ObservationHandler;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.context.event.ContextRefreshedEvent;
+import org.springframework.context.event.EventListener;
+import org.springframework.stereotype.Component;
+
+@Component
+public class ObservationHandlerLogger {
+
+    private static final Logger log = LoggerFactory.getLogger(ObservationHandlerLogger.class);
+
+    private static String toString(ObservationHandler<?> handler) {
+        return handler.getClass().getName() + " [ " + handler + "]";
+    }
+
+    @EventListener(ContextRefreshedEvent.class)
+    public void logObservationHandlers(ContextRefreshedEvent evt) {
+        evt.getApplicationContext().getBeansOfType(ObservationHandler.class)
+          .values()
+          .stream()
+          .map(ObservationHandlerLogger::toString)
+          .forEach(log::info);
+    }
+
+}
@@ -0,0 +1,21 @@
+package com.baeldung.samples.config;
+
+import io.micrometer.observation.Observation;
+import io.micrometer.observation.ObservationHandler;
+import io.micrometer.observation.ObservationTextPublisher;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+public class ObservationTextPublisherConfiguration {
+
+    private static final Logger log = LoggerFactory.getLogger(ObservationTextPublisherConfiguration.class);
+
+    @Bean
+    public ObservationHandler<Observation.Context> observationTextPublisher() {
+        return new ObservationTextPublisher(log::info);
+    }
+
+}
@@ -0,0 +1,20 @@
+package com.baeldung.samples.config;
+
+import io.micrometer.observation.ObservationRegistry;
+import io.micrometer.observation.aop.ObservedAspect;
+import org.springframework.boot.autoconfigure.AutoConfiguration;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.context.annotation.Bean;
+
+@AutoConfiguration
+@ConditionalOnClass(ObservedAspect.class)
+public class ObservedAspectConfiguration {
+
+    @Bean
+    @ConditionalOnMissingBean
+    public ObservedAspect observedAspect(ObservationRegistry observationRegistry) {
+        return new ObservedAspect(observationRegistry);
+    }
+
+}
@@ -0,0 +1,59 @@
+package com.baeldung.samples.config;
+
+import io.micrometer.observation.Observation;
+import io.micrometer.observation.ObservationHandler;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Component;
+
+@Component
+public class SimpleLoggingHandler implements ObservationHandler<Observation.Context> {
+
+    private static final Logger log = LoggerFactory.getLogger(SimpleLoggingHandler.class);
+
+    private static String toString(Observation.Context context) {
+        return null == context ? "(no context)" : context.getName()
+          + " (" + context.getClass().getName() + "@" + System.identityHashCode(context) + ")";
+    }
+
+    private static String toString(Observation.Event event) {
+        return null == event ? "(no event)" : event.getName();
+    }
+
+    @Override
+    public boolean supportsContext(Observation.Context context) {
+        return true;
+    }
+
+    @Override
+    public void onStart(Observation.Context context) {
+        log.info("Starting context " + toString(context));
+    }
+
+    @Override
+    public void onError(Observation.Context context) {
+        log.info("Error for context " + toString(context));
+    }
+
+    @Override
+    public void onEvent(Observation.Event event, Observation.Context context) {
+        log.info("Event for context " + toString(context) + " [" + toString(event) + "]");
+    }
+
+    @Override
+    public void onScopeOpened(Observation.Context context) {
+        log.info("Scope opened for context " + toString(context));
+
+    }
+
+    @Override
+    public void onScopeClosed(Observation.Context context) {
+        log.info("Scope closed for context " + toString(context));
+    }
+
+    @Override
+    public void onStop(Observation.Context context) {
+        log.info("Stopping context " + toString(context));
+    }
+
+}
@@ -0,0 +1,14 @@
+package com.baeldung.samples.domain;
+
+import io.micrometer.observation.annotation.Observed;
+import org.springframework.stereotype.Service;
+
+@Observed(name = "greetingService")
+@Service
+public class GreetingService {
+
+    public String sayHello() {
+        return "Hello World!";
+    }
+
+}
@@ -0,0 +1,6 @@
+management:
+  endpoints:
+    web:
+      exposure:
+        include: '*'
+        #health,info,beans,metrics,startup