Dynamically switch jmx/sensor names based on dual read mode and source type

CHANGELOG.md

@@ -14,6 +14,9 @@ and what APIs have changed, if applicable.
 
 ## [Unreleased]
 
+## [29.44.0] - 2023-08-06
+- dynamically switch jmx/sensor names based on dual read mode and source type
+
 ## [29.43.11] - 2023-08-01
 - fix logging issues about observer host and dual read mode
 
@@ -5512,7 +5515,8 @@ patch operations can re-use these classes for generating patch messages.
 
 ## [0.14.1]
 
-[Unreleased]: https://github.com/linkedin/rest.li/compare/v29.43.11...master
+[Unreleased]: https://github.com/linkedin/rest.li/compare/v29.44.0...master
+[29.44.0]: https://github.com/linkedin/rest.li/compare/v29.43.11...v29.44.0
 [29.43.11]: https://github.com/linkedin/rest.li/compare/v29.43.10...v29.43.11
 [29.43.10]: https://github.com/linkedin/rest.li/compare/v29.43.9...v29.43.10
 [29.43.9]: https://github.com/linkedin/rest.li/compare/v29.43.8...v29.43.9

d2/src/main/java/com/linkedin/d2/balancer/LastSeenBalancerWithFacilitiesFactory.java

@@ -59,7 +59,8 @@ public LoadBalancerWithFacilities create(D2ClientConfig config)
   {
     LOG.info("Creating D2 LoadBalancer based on LastSeenLoadBalancerWithFacilities");
 
-    D2ClientJmxManager d2ClientJmxManager = new D2ClientJmxManager(config.d2JmxManagerPrefix, config.jmxManager);
+    D2ClientJmxManager d2ClientJmxManager = new D2ClientJmxManager(config.d2JmxManagerPrefix, config.jmxManager,
+        D2ClientJmxManager.DiscoverySourceType.ZK, config.dualReadStateManager);
 
     // init connection
     ZKConnectionBuilder zkConnectionBuilder = new ZKConnectionBuilder(config.zkHosts);

d2/src/main/java/com/linkedin/d2/balancer/ZKFSLoadBalancerWithFacilitiesFactory.java

@@ -73,7 +73,8 @@ private ZKFSLoadBalancer.TogglingLoadBalancerFactory createLoadBalancerFactory(D
       loadBalancerComponentFactory = config.componentFactory;
     }
 
-    D2ClientJmxManager d2ClientJmxManager = new D2ClientJmxManager(config.d2JmxManagerPrefix, config.jmxManager);
+    D2ClientJmxManager d2ClientJmxManager = new D2ClientJmxManager(config.d2JmxManagerPrefix, config.jmxManager,
+        D2ClientJmxManager.DiscoverySourceType.ZK, config.dualReadStateManager);
 
     return new ZKFSTogglingLoadBalancerFactoryImpl(loadBalancerComponentFactory,
                                                    config.lbWaitTimeout,

d2/src/main/java/com/linkedin/d2/balancer/dualread/DualReadStateManager.java

@@ -22,6 +22,7 @@
 import com.linkedin.d2.balancer.properties.UriProperties;
 import com.linkedin.util.clock.Clock;
 import com.linkedin.util.clock.SystemClock;
+import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 import java.util.concurrent.ScheduledExecutorService;
@@ -32,7 +33,6 @@
 /**
  * Checks and manages the global and per-service dual read state.
  * Provides monitoring of the dual read data.
- *
  * The dual read state is broken down into global and per-service state. Per-service dual read
  * mode has a higher priority. Only if per-service dual read mode is not defined, global
  * dual read mode will be used.
@@ -52,6 +52,10 @@ public class DualReadStateManager
   private final RateLimiter _rateLimiter;
   // Stores global dual read mode
   private volatile DualReadModeProvider.DualReadMode _dualReadMode = DualReadModeProvider.DualReadMode.OLD_LB_ONLY;
+  private final Set<DualReadModeWatcher> _globalDualReadModeWatchers;
+  private final ConcurrentMap<String, Set<DualReadModeWatcher>> _serviceDualReadModeWatchers;
+  private final ConcurrentMap<String, Set<DualReadModeWatcher>> _clusterDualReadModeWatchers;
+
   private final DualReadLoadBalancerJmx _dualReadLoadBalancerJmx;
 
   private final DualReadLoadBalancerMonitor.UriPropertiesDualReadMonitor _uriPropertiesDualReadMonitor;
@@ -74,6 +78,9 @@ public DualReadStateManager(DualReadModeProvider dualReadModeProvider, Scheduled
     _dualReadModeProvider = dualReadModeProvider;
     _executorService = executorService;
     _rateLimiter = RateLimiter.create((double) 1 / DUAL_READ_MODE_SWITCH_MIN_INTERVAL);
+    _globalDualReadModeWatchers = ConcurrentHashMap.newKeySet();
+    _serviceDualReadModeWatchers = new ConcurrentHashMap<>();
+    _clusterDualReadModeWatchers = new ConcurrentHashMap<>();
   }
 
   public void updateGlobal(DualReadModeProvider.DualReadMode mode)
@@ -82,6 +89,7 @@ public void updateGlobal(DualReadModeProvider.DualReadMode mode)
     _dualReadMode = mode;
     if (updated) {
       LOG.info("Global dual read mode updated: {}", mode);
+      notifyGlobalWatchers();
     }
   }
 
@@ -90,6 +98,7 @@ public void updateService(String service, DualReadModeProvider.DualReadMode mode
     DualReadModeProvider.DualReadMode oldMode = _serviceDualReadModes.put(service, mode);
     if (oldMode != mode) {
       LOG.info("Dual read mode for service {} updated: {}", service, mode);
+      notifyServiceWatchers(service);
     }
   }
 
@@ -98,6 +107,7 @@ public void updateCluster(String cluster, DualReadModeProvider.DualReadMode mode
     DualReadModeProvider.DualReadMode oldMode = _clusterDualReadModes.put(cluster, mode);
     if (oldMode != mode) {
       LOG.info("Dual read mode for cluster {} updated: {}", cluster, mode);
+      notifyClusterWatchers(cluster);
     }
   }
 
@@ -198,4 +208,70 @@ public DualReadModeProvider getDualReadModeProvider()
   {
     return _dualReadModeProvider;
   }
+
+  public void addGlobalWatcher(DualReadModeWatcher watcher)
+  {
+    _globalDualReadModeWatchers.add(watcher);
+  }
+
+  public void addServiceWatcher(String serviceName, DualReadModeWatcher watcher)
+  {
+    Set<DualReadModeWatcher> watchers = _serviceDualReadModeWatchers.computeIfAbsent(serviceName, k -> ConcurrentHashMap.newKeySet());
+    watchers.add(watcher);
+  }
+
+  public void addClusterWatcher(String clusterName, DualReadModeWatcher watcher)
+  {
+    Set<DualReadModeWatcher> watchers = _clusterDualReadModeWatchers.computeIfAbsent(clusterName, k -> ConcurrentHashMap.newKeySet());
+    watchers.add(watcher);
+  }
+
+  public void removeServiceWatcher(String serviceName, DualReadModeWatcher watcher)
+  {
+    Set<DualReadModeWatcher> watchers = _serviceDualReadModeWatchers.get(serviceName);
+    if (watchers != null)
+    {
+      watchers.remove(watcher);
+    }
+  }
+
+  public void removeClusterWatcher(String clusterName, DualReadModeWatcher watcher)
+  {
+    Set<DualReadModeWatcher> watchers = _clusterDualReadModeWatchers.get(clusterName);
+    if (watchers != null)
+    {
+      watchers.remove(watcher);
+    }
+  }
+
+  private void notifyGlobalWatchers()
+  {
+    notifyWatchers(_globalDualReadModeWatchers);
+  }
+
+  private void notifyServiceWatchers(String serviceName)
+  {
+    notifyWatchers(_serviceDualReadModeWatchers.get(serviceName));
+  }
+
+  private void notifyClusterWatchers(String clusterName)
+  {
+    notifyWatchers(_clusterDualReadModeWatchers.get(clusterName));
+  }
+
+  private void notifyWatchers(Set<DualReadModeWatcher> watchers)
+  {
+    if (watchers != null)
+    {
+      for (DualReadModeWatcher w : watchers)
+      {
+        w.onChanged();
+      }
+    }
+  }
+
+  public interface DualReadModeWatcher
+  {
+    void onChanged();
+  }
 }