Agent lb on svm (#3795)

* add host if needed

* allow for test with null-host

* full coverage of states

* EnumSet.contains instead of Arrays.binarySearch

Author: DaanHoogland

server/src/main/java/org/apache/cloudstack/agent/lb/IndirectAgentLBServiceImpl.java

@@ -20,6 +20,7 @@
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.Comparator;
+import java.util.EnumSet;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -88,6 +89,14 @@ public List<String> getManagementServerList(final Long hostId, final Long dcId,
             hostIdList = getOrderedHostIdList(dcId);
         }
 
+        // just in case we have a host in creating state make sure it is in the list:
+        if (null != hostId && ! hostIdList.contains(hostId)) {
+            if (LOG.isTraceEnabled()) {
+                LOG.trace("adding requested host to host list as it does not seem to be there; " + hostId);
+            }
+            hostIdList.add(hostId);
+        }
+
         final org.apache.cloudstack.agent.lb.IndirectAgentLBAlgorithm algorithm = getAgentMSLBAlgorithm();
         final List<String> msList = Arrays.asList(msServerAddresses.replace(" ", "").split(","));
         return algorithm.sort(msList, hostIdList, hostId);
@@ -136,17 +145,54 @@ private List<Host> getAllAgentBasedHosts() {
         }
         final List <Host> agentBasedHosts = new ArrayList<>();
         for (final Host host : allHosts) {
-            if (host == null || host.getResourceState() == ResourceState.Creating || host.getResourceState() == ResourceState.Error) {
-                continue;
+            conditionallyAddHost(agentBasedHosts, host);
+        }
+        return agentBasedHosts;
+    }
+
+    private void conditionallyAddHost(List<Host> agentBasedHosts, Host host) {
+        if (host == null) {
+            if (LOG.isTraceEnabled()) {
+                LOG.trace("trying to add no host to a list");
             }
-            if (host.getType() == Host.Type.Routing || host.getType() == Host.Type.ConsoleProxy || host.getType() == Host.Type.SecondaryStorage || host.getType() == Host.Type.SecondaryStorageVM) {
-                if (host.getHypervisorType() != null && host.getHypervisorType() != Hypervisor.HypervisorType.KVM && host.getHypervisorType() != Hypervisor.HypervisorType.LXC) {
-                    continue;
-                }
-                agentBasedHosts.add(host);
+            return;
+        }
+
+        EnumSet<ResourceState> allowedStates = EnumSet.of(
+                ResourceState.Enabled,
+                ResourceState.Maintenance,
+                ResourceState.Disabled,
+                ResourceState.ErrorInMaintenance,
+                ResourceState.PrepareForMaintenance);
+        // so the remaining EnumSet<ResourceState> disallowedStates = EnumSet.complementOf(allowedStates)
+        // would be {ResourceState.Creating, ResourceState.Error};
+        if (!allowedStates.contains(host.getResourceState())) {
+            if (LOG.isTraceEnabled()) {
+                LOG.trace(String.format("host is in '%s' state, not adding to the host list, (id = %s)", host.getResourceState(), host.getUuid()));
             }
+            return;
         }
-        return agentBasedHosts;
+
+        if (host.getType() != Host.Type.Routing
+                && host.getType() != Host.Type.ConsoleProxy
+                && host.getType() != Host.Type.SecondaryStorage
+                && host.getType() != Host.Type.SecondaryStorageVM) {
+            if (LOG.isTraceEnabled()) {
+                LOG.trace(String.format("host is of wrong type, not adding to the host list, (id = %s, type = %s)", host.getUuid(), host.getType()));
+            }
+            return;
+        }
+
+        if (host.getHypervisorType() != null
+                && ! (host.getHypervisorType() == Hypervisor.HypervisorType.KVM || host.getHypervisorType() == Hypervisor.HypervisorType.LXC)) {
+
+            if (LOG.isTraceEnabled()) {
+                LOG.trace(String.format("hypervisor is not the right type, not adding to the host list, (id = %s, hypervisortype = %s)", host.getUuid(), host.getHypervisorType()));
+            }
+            return;
+        }
+
+        agentBasedHosts.add(host);
     }
 
     private org.apache.cloudstack.agent.lb.IndirectAgentLBAlgorithm getAgentMSLBAlgorithm() {