IGNITE-27429 Add client observableTs heartbeat propagation test (#7284)

Author: ptupitsyn

modules/runner/src/integrationTest/java/org/apache/ignite/internal/runner/app/client/ItThinClientObservationTsTest.java

@@ -17,8 +17,14 @@
 
 package org.apache.ignite.internal.runner.app.client;
 
+import static org.awaitility.Awaitility.await;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
+import java.time.Duration;
+import org.apache.ignite.client.IgniteClient;
+import org.apache.ignite.client.IgniteClient.Builder;
+import org.apache.ignite.internal.client.TcpIgniteClient;
+import org.apache.ignite.internal.hlc.HybridTimestampTracker;
 import org.apache.ignite.table.Table;
 import org.apache.ignite.table.Tuple;
 import org.apache.ignite.tx.Transaction;
@@ -65,4 +71,19 @@ public void test() {
         assertEquals("client value", directClientValue, directClientValue);
         assertEquals("client value", directSrvValue, directSrvValue);
     }
+
+    @Test
+    public void testObservableTsUpdatesOnHeartbeat() {
+        Builder clientBuilder = IgniteClient.builder()
+                .addresses(getClientAddresses().toArray(new String[0]))
+                .heartbeatInterval(100);
+
+        try (IgniteClient client = clientBuilder.build()) {
+            HybridTimestampTracker tsTracker = ((TcpIgniteClient) client).channel().observableTimestamp();
+
+            long initialTs = tsTracker.getLong();
+
+            await().atMost(Duration.ofSeconds(5)).until(() -> tsTracker.getLong() > initialTs);
+        }
+    }
 }