One of the notable Spring Boot 2 features is the introduction of Micrometer (SLF4J for application metrics).

Spring Boot ships with a whole series of built-in metrics collecting JVM metrics  (memory usage, garbage collection, threads, and classes), CPU usage, Tomcat metrics as well as others.

// dependencies block
compile 'org.springframework.boot:spring-boot-starter-actuator'

# enable actuator, use * to enable all endpoints
management.endpoints.web.exposure.include=info,health,metrics

You can query the metrics using the actuator HTTP endpoint:

curl http://localhost:8080/actuator/metrics/jvm.memory.used

{
   "name":"jvm.memory.used",
   "description":"The amount of used memory",
   "baseUnit":"bytes",
   "measurements":[
      {
         "statistic":"VALUE",
         "value":1.009509256E9
      }
   ],
   "availableTags":[
      {
         "tag":"area",
         "values":[
            "heap",
            "nonheap"
         ]
      },
      {
         "tag":"id",
         "values":[
            "Compressed Class Space",
            "PS Survivor Space",
            "PS Old Gen",
            "Metaspace",
            "PS Eden Space",
            "Code Cache"
         ]
      }
   ]
}

Please note that you need to authenticate if Spring Security is present.

Install InfluxDB and Grafana using Docker Compose

A simple way to run InfluxDB and Grafana locally is Docker Compose.

grafana:
  image: grafana/grafana:6.2.2
  ports:
    - 3000:3000
  volumes:
    - /var/lib/grafana
  environment:
    GF_SECURITY_ADMIN_PASSWORD: admin
influxdb:
  image: influxdb:1.7.6
  ports:
    - 8086:8086
  volumes:
    - /var/lib/influxdb
  environment:
    INFLUXDB_HTTP_AUTH_ENABLED: "true"
    INFLUXDB_USER: user
    INFLUXDB_USER_PASSWORD: pass
    INFLUXDB_DB: boot
    INFLUXDB_ADMIN_USER: admin
    INFLUXDB_ADMIN_PASSWORD: secret

Start InfluxDB and Grafana with docker-compose up .

Grafana is now running on http://localhost:3000. The default user is admin/admin.

Send Spring Boot Metrics to InfluxDB

Micrometer can send metrics to a series of destination using just configuration. You’ll only need to add the specific dependency and a few configuration values.

// dependencies block
compile 'io.micrometer:micrometer-registry-influx'

management.metrics.export.influx.db=boot
management.metrics.export.influx.userName=user
management.metrics.export.influx.password=pass
management.metrics.export.influx.uri=http://localhost:8086
management.metrics.export.influx.step=15s
management.metrics.export.influx.autoCreateDb=false

Grafana Configuration

The missing pieces to get Grafana up and running are:

1. Log in and change the admin password.
2. Add the InfluxDB data source.
   (host: http://influxdb:8086, admin credentials as in docker-compose.yml)
3. Create a Dashboard.

Fully Working Example

All steps above are combined into a working example published on github.com/gysel/spring-boot-metrics-influxdb. The example includes and automatic provisioning of Grafana. You don’t need to add a data source of a dashboard. Everything is configured in startup.