AMBARI-16270. Blueprint processor should create ConfigGroup even with only one host registered. (stoader)

ambari-server/src/main/java/org/apache/ambari/server/topology/AmbariContext.java

@@ -76,6 +76,11 @@ import org.apache.ambari.server.utils.RetryHelper;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import javax.annotation.Nullable;
+import com.google.common.collect.Iterables;
+import com.google.common.collect.Sets;
+
+
 /**
  * Provides topology related information as well as access to the core Ambari functionality.
  */
@@ -615,9 +620,28 @@ public class AmbariContext {
       groupHosts = topology.getHostGroupInfo().
           get(groupName).getHostNames();
 
+      // remove hosts that are not assigned to the cluster yet
+      String clusterName = null;
+      try {
+        clusterName = getClusterName(topology.getClusterId());
+      } catch (AmbariException e) {
+        LOG.error("Cannot get cluster name for clusterId = " + topology.getClusterId(), e);
+        throw new RuntimeException(e);
+      }
+
+      final Map<String, Host> clusterHosts = getController().getClusters().getHostsForCluster(clusterName);
+      Iterable<String> filteredGroupHosts = Iterables.filter(groupHosts, new com.google.common.base.Predicate<String>() {
+        @Override
+        public boolean apply(@Nullable String groupHost) {
+          return clusterHosts.containsKey(groupHost);
+        }
+      });
+
+
+
       ConfigGroupRequest request = new ConfigGroupRequest(
-          null, getClusterName(topology.getClusterId()), absoluteGroupName, service, "Host Group Configuration",
-          new HashSet<String>(groupHosts), serviceConfigs);
+          null, clusterName, absoluteGroupName, service, "Host Group Configuration",
+        Sets.newHashSet(filteredGroupHosts), serviceConfigs);
 
       // get the config group provider and create config group resource
       ConfigGroupResourceProvider configGroupProvider = (ConfigGroupResourceProvider)

ambari-server/src/test/java/org/apache/ambari/server/topology/AmbariContextTest.java

@@ -72,6 +72,7 @@ import org.junit.Test;
 
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.ImmutableList;
 
 /**
  * AmbariContext unit tests
@@ -200,6 +201,9 @@ public class AmbariContextTest {
     expect(clusters.getHost(HOST1)).andReturn(host1).anyTimes();
     expect(clusters.getHost(HOST2)).andReturn(host2).anyTimes();
 
+    Map<String, Host> clusterHosts = ImmutableMap.of(HOST1, host1, HOST2, host2);
+    expect(clusters.getHostsForCluster(CLUSTER_NAME)).andReturn(clusterHosts).anyTimes();
+
     expect(cluster.getClusterId()).andReturn(CLUSTER_ID).anyTimes();
     expect(cluster.getClusterName()).andReturn(CLUSTER_NAME).anyTimes();
 
@@ -358,6 +362,54 @@ public class AmbariContextTest {
     assertEquals("val3", requestProps.get("prop3"));
   }
 
+  @Test
+  public void testRegisterHostWithConfigGroup_createNewConfigGroupWithPendingHosts() throws Exception {
+    // test specific expectations
+    expect(cluster.getConfigGroups()).andReturn(Collections.<Long, ConfigGroup>emptyMap()).once();
+    expect(clusterController.ensureResourceProvider(Resource.Type.ConfigGroup)).andReturn(configGroupResourceProvider).once();
+    //todo: for now not using return value so just returning null
+    expect(configGroupResourceProvider.createResources(capture(configGroupRequestCapture))).andReturn(null).once();
+    configHelper.moveDeprecatedGlobals(stackId, group1Configuration.getFullProperties(1), CLUSTER_NAME);
+
+    reset(group1Info);
+    expect(group1Info.getConfiguration()).andReturn(group1Configuration).anyTimes();
+    Collection<String> groupHosts = ImmutableList.of(HOST1, HOST2, "pending_host"); // pending_host is not registered with the cluster
+    expect(group1Info.getHostNames()).andReturn(groupHosts).anyTimes(); // there are 3 hosts for the host group
+    // replay all mocks
+    replayAll();
+
+    // test
+    context.registerHostWithConfigGroup(HOST1, topology, HOST_GROUP_1);
+
+    // assertions
+    Set<ConfigGroupRequest> configGroupRequests = configGroupRequestCapture.getValue();
+    assertEquals(1, configGroupRequests.size());
+    ConfigGroupRequest configGroupRequest = configGroupRequests.iterator().next();
+    assertEquals(CLUSTER_NAME, configGroupRequest.getClusterName());
+    assertEquals("testBP:group1", configGroupRequest.getGroupName());
+    assertEquals("service1", configGroupRequest.getTag());
+    assertEquals("Host Group Configuration", configGroupRequest.getDescription());
+    Collection<String> requestHosts = configGroupRequest.getHosts();
+
+    // we expect only HOST1 and HOST2 in the config group request as the third host "pending_host" hasn't registered yet with the cluster
+    assertEquals(2, requestHosts.size());
+    assertTrue(requestHosts.contains(HOST1));
+    assertTrue(requestHosts.contains(HOST2));
+
+    Map<String, Config> requestConfig = configGroupRequest.getConfigs();
+    assertEquals(1, requestConfig.size());
+    Config type1Config = requestConfig.get("type1");
+    //todo: other properties such as cluster name are not currently being explicitly set on config
+    assertEquals("type1", type1Config.getType());
+    assertEquals("group1", type1Config.getTag());
+    Map<String, String> requestProps = type1Config.getProperties();
+    assertEquals(3, requestProps.size());
+    // 1.2 is overridden value
+    assertEquals("val1.2", requestProps.get("prop1"));
+    assertEquals("val2", requestProps.get("prop2"));
+    assertEquals("val3", requestProps.get("prop3"));
+  }
+
   @Test
   public void testRegisterHostWithConfigGroup_registerWithExistingConfigGroup() throws Exception {
     // test specific expectations