SOLR-12387: fixing a test failure

solr/core/src/java/org/apache/solr/handler/admin/CollectionsHandler.java

@@ -206,9 +206,10 @@ public class CollectionsHandler extends RequestHandlerBase implements Permission
     return this.coreContainer;
   }
 
-  protected void copyFromClusterProp(Map<String, Object> props, String prop) {
+  protected void copyFromClusterProp(Map<String, Object> props, String prop) throws IOException {
     if (props.get(prop) != null) return;//if it's already specified , return
-    Object defVal = coreContainer.getZkController().getZkStateReader().getClusterProperty(ImmutableList.of(COLLECTION_DEF, prop), null);
+    Object defVal = new ClusterProperties(coreContainer.getZkController().getZkStateReader().getZkClient())
+        .getClusterProperty(ImmutableList.of(COLLECTION_DEF, prop), null);
     if (defVal != null) props.put(prop, String.valueOf(defVal));
   }
 

solr/solrj/src/java/org/apache/solr/common/cloud/ClusterProperties.java

@@ -21,6 +21,7 @@ import java.io.IOException;
 import java.lang.invoke.MethodHandles;
 import java.util.Collections;
 import java.util.LinkedHashMap;
+import java.util.List;
 import java.util.Map;
 
 import org.apache.solr.common.SolrException;
@@ -67,6 +68,23 @@ public class ClusterProperties {
     return value;
   }
 
+  /**
+   * Read the value of a cluster property, returning a default if it is not set
+   *
+   * @param key          the property name or the full path to the property as a list of parts.
+   * @param defaultValue the default value
+   * @param <T>          the type of the property
+   * @return the property value
+   * @throws IOException if there is an error reading the value from the cluster
+   */
+  @SuppressWarnings("unchecked")
+  public <T> T getClusterProperty(List<String> key, T defaultValue) throws IOException {
+    T value = (T) Utils.getObjectByPath(getClusterProperties(), false, key);
+    if (value == null)
+      return defaultValue;
+    return value;
+  }
+
   /**
    * Return the cluster properties
    * @throws IOException if there is an error reading properties from the cluster

solr/solrj/src/java/org/apache/solr/common/cloud/ZkStateReader.java

@@ -961,6 +961,12 @@ public class ZkStateReader implements Closeable {
     return value;
   }
 
+  /**Same as the above but allows a full json path as a list of parts
+   *
+   * @param keyPath path to the property example ["collectionDefauls", "numShards"]
+   * @param defaultValue a default value to use if no such property exists
+   * @return the cluster property, or a default if the property is not set
+   */
   public <T> T getClusterProperty(List<String> keyPath, T defaultValue) {
     T value = (T) Utils.getObjectByPath( clusterProperties, false, keyPath);
     if (value == null)