Better monitoring with Spring boot Actuator

An overview of the features Spring boot actuator has to offer.

Transcript

1. Better monitoring with Spring boot Actuator
2. What is Spring boot Actuator? • Spring boot library • Adds production-ready features • Provides useful endpoints • Both over HTTP and JMX
3. Which endpoints are there? • Auditevents • Beans • Caches • Conditions • Configprops • Env • Flyway • Health • Heapdump • Httptrace • Info • Integrationgraph • Jolokia • Logfile • Loggers • Liquibase • Metrics • Mappings • Prometheus • Scheduledtasks • Sessions • Shutdown • Threaddump
4. How do I get started?
5. Add a dependency... <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </dependency>
6. … and configure what you need management: endpoints: web: exposure: include: env, info, health, metrics
7. And… what now?
8. Visit /actuator { "_links": { "self": { "href": "http://192.168.0.220:8080/actuator", "templated": false }, "health": { "href": "http://192.168.0.220:8080/actuator/health", "templated": false } }
9. Exploring the conditions endpoint
10. What does it do? • Which autoconfigurations are in use • Why are they (not) applied? • What can I do to make it work?
11. Visit /actuator/conditions { "positiveMatches": {/* ... */}, "negativeMatches": { "RabbitHealthContributorAutoConfiguration": { "notMatched": [ { "condition": "OnClassCondition", "message": "@ConditionalOnClass did not find required class 'org.springframework.amqp.rabbit.core.RabbitTemplate'" } ]
12. Exploring the env endpoint
13. What does it do? • Which application properties are loaded? • Where do these properties come from?
14. Visit /actuator/env { "activeProfiles": [ "dev" ], "propertySources": [ { "name": "applicationConfig: [classpath:/application-dev.yml]", "properties": { "server.port": { "value": 8080, "origin": "class path resource [application-dev.yml]:2:9"
15. Exploring the health endpoint
16. What does it do? • Is the database available? • Is there enough disk space? • Is Eureka available? • Is Solr available? • Useful for monitoring software • ...
17. Visit /actuator/health { "status": "UP" }
18. Showing detailed health info management: endpoint: health: show-details: always
19. Showing detailed health info { "status": "UP", "components": { "db": { "status": "UP", "details": { "database": "DB2 UDB for AS/400", "validationQuery": "SELECT 1 FROM SYSIBM.SYSDUMMY1", "result": 1 } }
20. Creating a custom health indicator @Component @RequiredArgsConstructor public class GitHubAPIHealthIndicator implements HealthIndicator { private final RestTemplate restTemplate; @Override public Health health() { // TODO: implement } }
21. Creating a custom health indicator try { var result = restTemplate.getForEntity("https://api.github.com/", ObjectNode.class); if (result.getStatusCode().is2xxSuccessful() && result.getBody() != null) { return Health.up().build(); } else { return Health.down().withDetail("status", result.getStatusCode()).build(); } } catch (RestClientException ex) { return Health.down().withException(ex).build(); }
22. Creating a custom health indicator { "status": "UP", "components": { "gitHubAPI": { "status": "UP" } } }
23. Useful for monitoring
24. Useful for Eureka
25. Exploring the heapdump endpoint
26. What does it do? • Returns *.HPROF file • Can be imported in JVisualVM, … • Find memory leaks and other peformance issues
27. Open the *.HPROF file
28. Exploring the info endpoint
29. What does it do? • Returns additional information • By default empty • Useful in combination with Maven resource filtering
30. Configuring info info: contributors: Dimitri Mestdagh project-version: @project-version@ build-timestamp: @maven.build.timestamp@
31. Visit /actuator/info { "contributors": "Dimitri Mestdagh", "project-version": "0.0.1-SNAPSHOT", "build-timestamp": "2020-06-27 11:52:30" }
32. Exploring the loggers endpoint
33. What does it do? • What logging levels are in use? • Change runtime logging levels • Useful for debugging
34. Visit /actuator/loggers { "loggers": { "ROOT": { "configuredLevel": "INFO", "effectiveLevel": "INFO" }, "be.g00glen00b": { "configuredLevel": null, "effectiveLevel": "INFO" } } }
35. Changing the runtime logger levels curl \ --header "Content-Type: application/json" \ --request POST \ --data '{"configuredLevel": "DEBUG"}' \ http://localhost:8080/actuator/loggers/be.g00glen00b
36. Exploring the metrics endpoint
37. What does it do? • Application metrics • Uses micrometer • Counters • Gauges • Distribution summaries • Percentiles • Timers
38. Visit /actuator/metrics { "names": [ "cache.evictions", "http.server.requests", "jvm.threads.states", "hystrix.execution", "spring.batch.chunk.write", "spring.batch.item.process", "hystrix.latency.total", "jvm.memory.used" ] }
39. Visit /actuator/metrics/{metric} { "name": "jvm.memory.used", "description": "The amount of used memory", "baseUnit": "bytes", "measurements": [{ "statistic": "VALUE", "value": 196616376 }], "availableTags": [{ "tag": "area", "values": ["heap", "nonheap"] }]
40. Visit /actuator/metrics/{metric}?tag=area:heap { "name": "jvm.memory.used", "description": "The amount of used memory", "baseUnit": "bytes", "measurements": [{ "statistic": "VALUE", "value": 196616376 }], "availableTags": [] }
41. Creating custom counter metrics @Bean public Counter invoicesCounter(MeterRegistry registry) { return Counter .builder("invoices.created") .description("Amount of invoices created") .register(registry); }
42. Creating custom counter metrics @PostMapping public CreatedInvoiceDTO create(@RequestBody InvoiceParametersDTO parameters) { counter.increment(); // Add this return facade.create(parameters); }
43. Creating custom gauge metrics @Bean public Gauge countOrdersGauge(MeterRegistry registry, OrderRepository repository) { return Gauge .builder("order.count", repository::count) .description("Amount of registered orders”) .register(registry); }
44. Cool stuff… but why?
45. Cool stuff… but why? • Production-readiness • Better monitoring • Better logging • Better debugging = More happy people
46. Resources • https://docs.spring.io/spring-boot/docs/current/reference/html/p roduction-ready-features.html • https://dimitr.im/mastering-spring-boot-actuator Shameless self-promotion
47. Thank you for listening!