Fix KvmSshToAgentEnabled setting description and make it dynamic

Author: nvazquez

engine/components-api/src/main/java/com/cloud/resource/ResourceManager.java

@@ -57,8 +57,8 @@ public interface ResourceManager extends ResourceService, Configurable {
 
     ConfigKey<Boolean> KvmSshToAgentEnabled = new ConfigKey<>("Advanced", Boolean.class,
             "kvm.ssh.to.agent","true",
-            "Number of retries when preparing a host into Maintenance Mode is faulty before failing",
-            false);
+            "True if the management server will restart the agent service via SSH into the KVM hosts after or during maintenance operations",
+            true);
 
     ConfigKey<String> HOST_MAINTENANCE_LOCAL_STRATEGY = new ConfigKey<>(String.class,
     "host.maintenance.local.storage.strategy", "Advanced","Error",

server/src/main/java/com/cloud/resource/ResourceManagerImpl.java

@@ -3833,8 +3833,7 @@ protected void handleAgentIfNotConnected(HostVO host, boolean vmsMigrating) {
         if (!isAgentOnHost || vmsMigrating || host.getStatus() == Status.Up) {
             return;
         }
-        final boolean sshToAgent = Boolean.parseBoolean(_configDao.getValue(KvmSshToAgentEnabled.key()));
-        if (sshToAgent) {
+        if (KvmSshToAgentEnabled.value()) {
             Ternary<String, String, String> credentials = getHostCredentials(host);
             connectAndRestartAgentOnHost(host, credentials.first(), credentials.second(), credentials.third());
         } else {

server/src/test/java/com/cloud/resource/ResourceManagerImplTest.java

@@ -21,6 +21,7 @@
 import com.cloud.agent.api.GetVncPortAnswer;
 import com.cloud.agent.api.GetVncPortCommand;
 import com.cloud.capacity.dao.CapacityDao;
+import com.cloud.configuration.ConfigurationManagerImpl;
 import com.cloud.dc.ClusterVO;
 import com.cloud.dc.DataCenterVO;
 import com.cloud.dc.HostPodVO;
@@ -57,6 +58,7 @@
 import org.apache.cloudstack.api.command.admin.host.DeclareHostAsDegradedCmd;
 import org.apache.cloudstack.engine.subsystem.api.storage.DataStore;
 import org.apache.cloudstack.engine.subsystem.api.storage.PrimaryDataStoreInfo;
+import org.apache.cloudstack.framework.config.ConfigKey;
 import org.apache.cloudstack.framework.config.dao.ConfigurationDao;
 import org.apache.cloudstack.storage.datastore.db.PrimaryDataStoreDao;
 import org.apache.cloudstack.storage.datastore.db.StoragePoolVO;
@@ -75,6 +77,7 @@
 import org.mockito.Spy;
 import org.mockito.junit.MockitoJUnitRunner;
 
+import java.lang.reflect.Field;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -179,6 +182,12 @@ public class ResourceManagerImplTest {
     private MockedConstruction<GetVncPortCommand> getVncPortCommandMockedConstruction;
     private AutoCloseable closeable;
 
+    private void overrideDefaultConfigValue(final ConfigKey configKey, final String name, final Object o) throws IllegalAccessException, NoSuchFieldException {
+        Field f = ConfigKey.class.getDeclaredField(name);
+        f.setAccessible(true);
+        f.set(configKey, o);
+    }
+
     @Before
     public void setup() throws Exception {
         closeable = MockitoAnnotations.openMocks(this);
@@ -221,7 +230,7 @@ public void setup() throws Exception {
                 eq("service cloudstack-agent restart"))).
                 willReturn(new SSHCmdHelper.SSHCmdResult(0,"",""));
 
-        when(configurationDao.getValue(ResourceManager.KvmSshToAgentEnabled.key())).thenReturn("true");
+        overrideDefaultConfigValue(ResourceManager.KvmSshToAgentEnabled, "_defaultValue", "true");
 
         rootDisks = Arrays.asList(rootDisk1, rootDisk2);
         dataDisks = Collections.singletonList(dataDisk);
@@ -383,8 +392,9 @@ public void testConnectAndRestartAgentOnHost() {
     }
 
     @Test
-    public void testHandleAgentSSHEnabledNotConnectedAgent() {
+    public void testHandleAgentSSHEnabledNotConnectedAgent() throws NoSuchFieldException, IllegalAccessException {
         when(host.getStatus()).thenReturn(Status.Disconnected);
+        overrideDefaultConfigValue(ResourceManager.KvmSshToAgentEnabled, "_defaultValue", "true");
         resourceManager.handleAgentIfNotConnected(host, false);
         verify(resourceManager).getHostCredentials(eq(host));
         verify(resourceManager).connectAndRestartAgentOnHost(eq(host), eq(hostUsername), eq(hostPassword), eq(hostPrivateKey));
@@ -399,9 +409,9 @@ public void testHandleAgentSSHEnabledConnectedAgent() {
     }
 
     @Test(expected = CloudRuntimeException.class)
-    public void testHandleAgentSSHDisabledNotConnectedAgent() {
+    public void testHandleAgentSSHDisabledNotConnectedAgent() throws NoSuchFieldException, IllegalAccessException {
         when(host.getStatus()).thenReturn(Status.Disconnected);
-        when(configurationDao.getValue(ResourceManager.KvmSshToAgentEnabled.key())).thenReturn("false");
+        overrideDefaultConfigValue(ResourceManager.KvmSshToAgentEnabled, "_defaultValue", "false");
         resourceManager.handleAgentIfNotConnected(host, false);
     }