Add keycloak online/offline sessions records

README.md

@@ -200,6 +200,24 @@ This counter counts the number of response errors (responses where the http stat
 keycloak_response_errors{code="500",method="GET",} 1
 ```
 
+##### keycloak_online_sessions
+This gauge records the number of online sessions.
+
+```c
+# HELP keycloak_online_sessions Total online sessions
+# TYPE keycloak_online_sessions gauge
+keycloak_online_sessions{realm="test",client_id="application1",} 1.0
+```
+
+##### keycloak_offline_sessions
+This gauge records the number of offline sessions.
+
+```c
+# HELP keycloak_offline_sessions Total offline sessions
+# TYPE keycloak_offline_sessions gauge
+keycloak_offline_sessions{realm="test",client_id="application1",} 1.0
+```
+
 ## Grafana Dashboard
 
 You can use this dashboard or create yours https://grafana.com/dashboards/10441

src/main/java/org/jboss/aerogear/keycloak/metrics/MetricsEventListener.java

@@ -1,16 +1,26 @@
 package org.jboss.aerogear.keycloak.metrics;
 
+import java.util.Map;
+import java.util.HashMap;
 import org.jboss.logging.Logger;
 import org.keycloak.events.Event;
 import org.keycloak.events.EventListenerProvider;
 import org.keycloak.events.admin.AdminEvent;
+import org.keycloak.models.KeycloakSession;
+import org.keycloak.models.RealmModel;
 
 public class MetricsEventListener implements EventListenerProvider {
 
     public final static String ID = "metrics-listener";
 
     private final static Logger logger = Logger.getLogger(MetricsEventListener.class);
 
+    private KeycloakSession session;
+
+    public MetricsEventListener (KeycloakSession session) {
+        this.session = session;
+    }
+
     @Override
     public void onEvent(Event event) {
         logEventDetails(event);
@@ -31,13 +41,32 @@ public void onEvent(Event event) {
             default:
                 PrometheusExporter.instance().recordGenericEvent(event);
         }
+
+        setSessions(session.realms().getRealm(event.getRealmId()));
     }
 
     @Override
     public void onEvent(AdminEvent event, boolean includeRepresentation) {
         logAdminEventDetails(event);
 
         PrometheusExporter.instance().recordGenericAdminEvent(event);
+
+        setSessions(session.realms().getRealm(event.getRealmId()));
+    }
+
+    private void setSessions(RealmModel realm) {
+
+        Map<String,Long> onlineSessions = new HashMap<String,Long>();
+        session.sessions().getActiveClientSessionStats(realm,false).forEach((id, count) -> 
+            onlineSessions.put(realm.getClientById(id).getClientId(), count)
+        );
+
+        Map<String,Long> offlineSessions = new HashMap<String,Long>(); 
+        session.sessions().getActiveClientSessionStats(realm,true).forEach((id, count) -> 
+            offlineSessions.put(realm.getClientById(id).getClientId(), count)
+        );
+
+        PrometheusExporter.instance().recordSessions(realm.getId(), onlineSessions, offlineSessions);
     }
 
     private void logEventDetails(Event event) {

src/main/java/org/jboss/aerogear/keycloak/metrics/MetricsEventListenerFactory.java

@@ -10,7 +10,7 @@ public class MetricsEventListenerFactory implements EventListenerProviderFactory
 
     @Override
     public EventListenerProvider create(KeycloakSession session) {
-        return new MetricsEventListener();
+        return new MetricsEventListener(session);
     }
 
     @Override

src/main/java/org/jboss/aerogear/keycloak/metrics/PrometheusExporter.java

@@ -2,6 +2,7 @@
 
 import io.prometheus.client.CollectorRegistry;
 import io.prometheus.client.Counter;
+import io.prometheus.client.Gauge;
 import io.prometheus.client.Histogram;
 import io.prometheus.client.exporter.PushGateway;
 import io.prometheus.client.exporter.common.TextFormat;
@@ -37,6 +38,8 @@ public final class PrometheusExporter {
     final Counter totalRegistrationsErrors;
     final Counter responseErrors;
     final Histogram requestDuration;
+    final Gauge totalOnlineSessions;
+    final Gauge totalOfflineSessions;
     final PushGateway PUSH_GATEWAY;
 
     private PrometheusExporter() {
@@ -89,6 +92,17 @@ private PrometheusExporter() {
             .labelNames("method")
             .register();
 
+        totalOnlineSessions = Gauge.build()
+            .name("keycloak_online_sessions")
+            .help("Total online sessions")
+            .labelNames("realm", "client_id")
+            .register();
+        totalOfflineSessions = Gauge.build()
+            .name("keycloak_offline_sessions")
+            .help("Total offline sessions")
+            .labelNames("realm", "client_id")
+            .register();
+
         // Counters for all user events
         for (EventType type : EventType.values()) {
             if (type.equals(EventType.LOGIN) || type.equals(EventType.LOGIN_ERROR) || type.equals(EventType.REGISTER)) {
@@ -208,6 +222,23 @@ public void recordLoginError(final Event event) {
         pushAsync();
     }
 
+    /**
+     * Set sessions number
+     *
+     * @param event LoginError event
+     */
+    public void recordSessions(final String realmId, Map<String,Long> onlineSessions, Map<String,Long> offlineSessions) {
+
+        onlineSessions.forEach((clientId, count) -> {
+            totalOnlineSessions.labels(nullToEmpty(realmId), nullToEmpty(clientId)).set(count);
+        });
+
+        offlineSessions.forEach((clientId, count) -> {
+            totalOfflineSessions.labels(nullToEmpty(realmId), nullToEmpty(clientId)).set(count);
+        });
+        pushAsync();
+    }
+
     /**
      * Record the duration between one request and response
      *

src/test/java/org/jboss/aerogear/keycloak/metrics/PrometheusExporterTest.java

@@ -18,6 +18,7 @@
 import java.lang.reflect.Field;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.Map;
 
 import static org.hamcrest.CoreMatchers.containsString;
 import static org.hamcrest.CoreMatchers.is;
@@ -177,6 +178,19 @@ public void shouldCorrectlyRecordResponseErrors() throws IOException {
         assertGenericMetric("keycloak_response_errors", 1, tuple("code", "500"), tuple("method", "POST"));
     }
 
+    @Test
+    public void shouldCorrectlyRecordSessions() throws IOException {
+
+        Map<String,Long> map1 = Map.of("account", new Long(10), "admin-cli", new Long(0));
+        Map<String,Long> map2 = Map.of("account", new Long(0), "admin-cli", new Long(10));
+
+        PrometheusExporter.instance().recordSessions(DEFAULT_REALM, map1, map2);
+        assertGenericMetric("keycloak_online_sessions", 10, tuple("realm", DEFAULT_REALM), tuple("client_id", "account"));
+        assertGenericMetric("keycloak_online_sessions", 0, tuple("realm", DEFAULT_REALM), tuple("client_id", "admin-cli"));
+        assertGenericMetric("keycloak_offline_sessions", 0, tuple("realm", DEFAULT_REALM), tuple("client_id", "account"));
+        assertGenericMetric("keycloak_offline_sessions", 10, tuple("realm", DEFAULT_REALM), tuple("client_id", "admin-cli"));
+    }
+
     @Test
     public void shouldTolerateNullLabels() throws IOException {
         final Event nullEvent = new Event();