Datanode periodical for NodeService pings (#15003)

* Datanode periodical for NodeService pings

* node service markAsAlive update without additional query

* added unit test for NodePingPeriodical

* code cleanup

* simplified NodePingPeriodicalTest

data-node/src/test/java/org/graylog/datanode/periodicals/NodePingPeriodicalTest.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2020 Graylog, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the Server Side Public License, version 1,
+ * as published by MongoDB, Inc.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * Server Side Public License for more details.
+ *
+ * You should have received a copy of the Server Side Public License
+ * along with this program. If not, see
+ * <http://www.mongodb.com/licensing/server-side-public-license>.
+ */
+package org.graylog.datanode.periodicals;
+
+import org.graylog2.cluster.NodeNotFoundException;
+import org.graylog2.cluster.NodeService;
+import org.graylog2.plugin.system.SimpleNodeId;
+import org.junit.jupiter.api.Test;
+import org.mockito.Mockito;
+
+import java.net.URI;
+
+class NodePingPeriodicalTest {
+
+    @Test
+    void doRun() throws NodeNotFoundException {
+
+        final SimpleNodeId nodeID = new SimpleNodeId("5ca1ab1e-0000-4000-a000-000000000000");
+        final URI uri = URI.create("http://localhost:8999");
+        final NodeService nodeService = Mockito.mock(NodeService.class);
+
+        final NodePingPeriodical task = new NodePingPeriodical(
+                nodeService,
+                nodeID,
+                uri,
+                () -> true
+        );
+
+        task.doRun();
+
+        Mockito.verify(nodeService).markAsAlive(
+                Mockito.eq(nodeID),
+                Mockito.eq(true),
+                Mockito.eq(uri));
+    }
+
+
+    @Test
+    void doRunWithRegister() throws NodeNotFoundException {
+
+        final SimpleNodeId nodeID = new SimpleNodeId("5ca1ab1e-0000-4000-a000-000000000000");
+        final URI uri = URI.create("http://localhost:8999");
+
+        final NodeService nodeService = Mockito.mock(NodeService.class);
+
+        Mockito.doThrow(new NodeNotFoundException("Node not found")).when(nodeService).markAsAlive(nodeID, true, uri);
+
+        final NodePingPeriodical task = new NodePingPeriodical(
+                nodeService,
+                nodeID,
+                uri,
+                () -> true
+        );
+
+        task.doRun();
+
+        Mockito.verify(nodeService).registerServer(
+                Mockito.eq(nodeID.getNodeId()),
+                Mockito.eq(true),
+                Mockito.eq(uri),
+                Mockito.any()
+        );
+    }
+}