44-Spring-Boot-Actuator

Question 1

What is the default actuator endpoint? How to change it?

Answer 1

/actuator

management.endpoints.web.base-path=/admin

Question 2

How to get the list of supported metrics?

Answer 2

/actuator/metrics returns {names: […]}

Question 3

Configuration to expose metrics via HTTP?

Answer 3

management.endpoints.web.exposure.include=metrics

Question 4

URL to view details of a metric?

Answer 4

/actuator/metrics/metric-name

Question 5

List out 10 actuator endpoints

Answer 5

health
info
metrics
liquibase
flyway
auditevents
beans
caches
conditions
env
loggers
mappings
sessions
threaddump
shutdown

Question 6

What endpoints are enabled and exposed via HTTP?

Answer 6

HTTP: all enabled except shutdown, httptrace, and auditevents. Expose only heath and info

Question 7

How to enabled endpoints via JMX?

Answer 7

spring.jmx.enabled=true

Question 8

By default, what endpoints are disabled via HTTP?

Answer 8

shutdown, httptrace and auditevents

Question 9

What endpoints are enabled and exposed via JMX?

Answer 9

JMX: disabled by default, all enabled are exposed

Question 10

How to expose all endpoints via HTTP?

Answer 10

management.endpoints.web.exposure.include=*

Note: endpoints with s

Question 11

2 ways to secure endpoints via Spring Security?

Answer 11

With Spring security:
http.authorizeRequests()
    .mvcMatcher("/actuator/**").hasRole("ACTUATOR")
    .anyRequest().authenticated();
OR:
http.authorizeRequests()
    .requestMatchers(EndpointRequest.toAnyEndpoint()).hasRole("ACTUATOR)
    .anyRequest().authenticated();

Question 12

List out custom metric classes

Answer 12

Counter
Gauge
Timer
DistributionSummary

Question 13

How to register a metric?

Answer 13

Inject and use MeterRegistry

Question 14

What is the naming convention of hierarchical HTTP metrics?

Answer 14

http.method.$methodName.status.$statusName

Question 15

How to get the value of a tagged HTTP metric by status and method?

Answer 15

http?tag=method:get&tag=status:200

Question 16

Configuration to enable viewing details of health indicators?

Answer 16

management.endpoint.health.show-details=always

Note: endpoint without s

Question 17

List out 10 health indicators

Answer 17

db
diskSpace
jms
ldap
redis
ping
mail
influxdb, cassandra, couchbase, elasticsearch, mongo, neo4j, rabbit, solr

Question 18

How to create a group of health indicators?

Answer 18

management.endpoint.health.group.group-name.include=diskSpace,db
will returns: {status: “UP”, groups: [“group-name”]}
Note: endpoint without s

Question 19

Configuration to enable viewing details of a health indicator group?

Answer 19

management.endpoint.health.group.groupName.show-details=always
Note: endpoint without s

Question 20

Steps to build a custom health indicator?

Answer 20

1. Extend AbstractHealthIndicator.doHealthCheck() or implement HealthIndicator.health()
2. Mark class as a component

Question 21

Built-in health status values

Answer 21

DOWN
OUT_OF_SERVICE
UNKNOWN
UP

Question 22

How to override severity order?

Answer 22

management. endpoint.heath.status.order=FATAL, DOWN, OUT_OF_SERVICE, UNKNOWN, UP
(management. heath.status.order is deprecated)