How to export metrics to Prometheus via PushGateway using Spring Boot 2.0 - spring-boot

Question

I upgraded Spring Boot version from 1.5.x to 2.0.1, but struggled with an issue of new Metrics.
To use micrometer In Spring boot 2.0+, I must remove the <dependency/> of micrometer-spring-legacy. Unfortunately, all of the config of management.metrics.export.prometheus.pushgateway disappeared. So how can I export metrics to pushgateway using spring boot 2.0?
Many thanks!

Answer 1

Unfortunately the Prometheus Pushgateway auto-configuration hasn't made it into Spring-Boot 2. Unsure if a PR which incorporates the micromter-spring-legacy setup would be accepted.
In the meantime you could try to setup your own #Configuration class which includes everything starting here.
Here's a quickly stitched together solution:
#Configuration
#EnableConfigurationProperties(PushgatewayProperties.class)
public class PushgatewayConfiguration {
#ConfigurationProperties(prefix = "management.metrics.export.prometheus.pushgateway")
public static class PushgatewayProperties {
/**
* Enable publishing via a Prometheus Pushgateway.
*/
private Boolean enabled = false;
/**
* Required host:port or ip:port of the Pushgateway.
*/
private String baseUrl = "localhost:9091";
/**
* Required identifier for this application instance.
*/
private String job;
/**
* Frequency with which to push metrics to Pushgateway.
*/
private Duration pushRate = Duration.ofMinutes(1);
/**
* Push metrics right before shut-down. Mostly useful for batch jobs.
*/
private boolean pushOnShutdown = true;
/**
* Delete metrics from Pushgateway when application is shut-down
*/
private boolean deleteOnShutdown = true;
/**
* Used to group metrics in pushgateway. A common example is setting
*/
private Map<String, String> groupingKeys = new HashMap<>();
public Boolean getEnabled() {
return enabled;
}
public void setEnabled(Boolean enabled) {
this.enabled = enabled;
}
public String getBaseUrl() {
return baseUrl;
}
public void setBaseUrl(String baseUrl) {
this.baseUrl = baseUrl;
}
public String getJob() {
return job;
}
public void setJob(String job) {
this.job = job;
}
public Duration getPushRate() {
return pushRate;
}
public void setPushRate(Duration pushRate) {
this.pushRate = pushRate;
}
public boolean isPushOnShutdown() {
return pushOnShutdown;
}
public void setPushOnShutdown(boolean pushOnShutdown) {
this.pushOnShutdown = pushOnShutdown;
}
public boolean isDeleteOnShutdown() {
return deleteOnShutdown;
}
public void setDeleteOnShutdown(boolean deleteOnShutdown) {
this.deleteOnShutdown = deleteOnShutdown;
}
public Map<String, String> getGroupingKeys() {
return groupingKeys;
}
public void setGroupingKeys(Map<String, String> groupingKeys) {
this.groupingKeys = groupingKeys;
}
}
static class PrometheusPushGatewayEnabledCondition extends AllNestedConditions {
public PrometheusPushGatewayEnabledCondition() {
super(ConfigurationPhase.PARSE_CONFIGURATION);
}
#ConditionalOnProperty(value = "management.metrics.export.prometheus.enabled", matchIfMissing = true)
static class PrometheusMeterRegistryEnabled {
//
}
#ConditionalOnProperty("management.metrics.export.prometheus.pushgateway.enabled")
static class PushGatewayEnabled {
//
}
}
/**
* Configuration for
* <a href="https://github.com/prometheus/pushgateway">Prometheus
* Pushgateway</a>.
*
* #author David J. M. Karlsen
*/
#Configuration
#ConditionalOnClass(PushGateway.class)
#Conditional(PrometheusPushGatewayEnabledCondition.class)
#Incubating(since = "1.0.0")
public class PrometheusPushGatewayConfiguration {
private final Logger logger = LoggerFactory.getLogger(PrometheusPushGatewayConfiguration.class);
private final CollectorRegistry collectorRegistry;
private final PushgatewayProperties pushgatewayProperties;
private final PushGateway pushGateway;
private final Environment environment;
private final ScheduledExecutorService executorService;
PrometheusPushGatewayConfiguration(CollectorRegistry collectorRegistry,
PushgatewayProperties pushgatewayProperties, Environment environment) {
this.collectorRegistry = collectorRegistry;
this.pushgatewayProperties = pushgatewayProperties;
this.pushGateway = new PushGateway(pushgatewayProperties.getBaseUrl());
this.environment = environment;
this.executorService = Executors.newSingleThreadScheduledExecutor((r) -> {
final Thread thread = new Thread(r);
thread.setDaemon(true);
thread.setName("micrometer-pushgateway");
return thread;
});
executorService.scheduleAtFixedRate(this::push, 0, pushgatewayProperties.getPushRate().toMillis(),
TimeUnit.MILLISECONDS);
}
void push() {
try {
pushGateway.pushAdd(collectorRegistry, job(), pushgatewayProperties.getGroupingKeys());
} catch (UnknownHostException e) {
logger.error("Unable to locate host '" + pushgatewayProperties.getBaseUrl()
+ "'. No longer attempting metrics publication to this host");
executorService.shutdown();
} catch (Throwable t) {
logger.error("Unable to push metrics to Prometheus Pushgateway", t);
}
}
#PreDestroy
void shutdown() {
executorService.shutdown();
if (pushgatewayProperties.isPushOnShutdown()) {
push();
}
if (pushgatewayProperties.isDeleteOnShutdown()) {
try {
pushGateway.delete(job(), pushgatewayProperties.getGroupingKeys());
} catch (Throwable t) {
logger.error("Unable to delete metrics from Prometheus Pushgateway", t);
}
}
}
private String job() {
String job = pushgatewayProperties.getJob();
if (job == null) {
job = environment.getProperty("spring.application.name");
}
if (job == null) {
// There's a history of Prometheus spring integration defaulting the job name to
// "spring" from when
// Prometheus integration didn't exist in Spring itself.
job = "spring";
}
return job;
}
}
}