SOLR-10278: added more tests and a SolrJ based client state provider

solr/solrj/src/java/org/apache/solr/client/solrj/impl/CloudSolrClient.java

@@ -60,6 +60,7 @@ import org.apache.solr.common.SolrException.ErrorCode;
 import org.apache.solr.common.SolrInputDocument;
 import org.apache.solr.common.ToleratedUpdateError;
 import org.apache.solr.common.cloud.ClusterState;
+import org.apache.solr.common.cloud.ClusterState.CollectionRef;
 import org.apache.solr.common.cloud.CollectionStatePredicate;
 import org.apache.solr.common.cloud.CollectionStateWatcher;
 import org.apache.solr.common.cloud.DocCollection;
@@ -1445,7 +1446,7 @@ public class CloudSolrClient extends SolrClient {
           && !cacheEntry.shoulRetry()) return col;
     }
 
-    ClusterState.CollectionRef ref = getCollectionRef(collection);
+    CollectionRef ref = getCollectionRef(collection);
     if (ref == null) {
       //no such collection exists
       return null;
@@ -1480,7 +1481,7 @@ public class CloudSolrClient extends SolrClient {
     }
   }
 
-  ClusterState.CollectionRef getCollectionRef(String collection) {
+  CollectionRef getCollectionRef(String collection) {
     return stateProvider.getState(collection);
   }
 
@@ -1729,9 +1730,9 @@ public class CloudSolrClient extends SolrClient {
     }
   }
 
-  interface ClusterStateProvider extends Closeable {
+  public interface ClusterStateProvider extends Closeable {
 
-    ClusterState.CollectionRef getState(String collection);
+    CollectionRef getState(String collection);
 
     Set<String> liveNodes();
 
@@ -1741,6 +1742,8 @@ public class CloudSolrClient extends SolrClient {
 
     Map<String, Object> getClusterProperties();
 
+    Map<String,CollectionRef> getCollections();
+
     void connect();
   }
 }

solr/solrj/src/java/org/apache/solr/client/solrj/impl/ZkClientClusterStateProvider.java

@@ -27,6 +27,8 @@ import java.util.Set;
 import org.apache.solr.common.SolrException;
 import org.apache.solr.common.cloud.Aliases;
 import org.apache.solr.common.cloud.ClusterState;
+import org.apache.solr.common.cloud.ClusterState.CollectionRef;
+import org.apache.solr.common.cloud.DocCollection;
 import org.apache.solr.common.cloud.ZkStateReader;
 import org.apache.solr.common.cloud.ZooKeeperException;
 import org.apache.zookeeper.KeeperException;
@@ -52,7 +54,7 @@ public class ZkClientClusterStateProvider implements CloudSolrClient.ClusterStat
   }
 
   @Override
-  public ClusterState.CollectionRef getState(String collection) {
+  public CollectionRef getState(String collection) {
     return zkStateReader.getClusterState().getCollectionRef(collection);
   }
 
@@ -181,6 +183,11 @@ public class ZkClientClusterStateProvider implements CloudSolrClient.ClusterStat
     return zkHostString;
   }
 
+  @Override
+  public Map<String, CollectionRef> getCollections() {
+    return zkStateReader.getClusterState().getCollectionStates();
+  }
+
   @Override
   public String toString() {
     return zkHost;

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

@@ -25,6 +25,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
+import java.util.function.BiConsumer;
 
 import org.apache.solr.common.SolrException;
 import org.apache.solr.common.SolrException.ErrorCode;
@@ -165,6 +166,10 @@ public class DocCollection extends ZkNodeProps implements Iterable<Slice> {
     return slices.get(sliceName);
   }
 
+  public void forEachReplica(BiConsumer<String, Replica> consumer) {
+    slices.forEach((shard, slice) -> slice.getReplicasMap().forEach((s, replica) -> consumer.accept(shard, replica)));
+  }
+
   /**
    * Gets the list of all slices for this collection.
    */

solr/solrj/src/java/org/apache/solr/common/util/Utils.java

@@ -68,9 +68,10 @@ public class Utils {
   }
 
   private static Object makeDeepCopy(Object v, int maxDepth, boolean mutable) {
-    if (v instanceof MapWriter) v = ((MapWriter) v).toMap(new LinkedHashMap<>());
+    if (v instanceof MapWriter && maxDepth > 1) v = ((MapWriter) v).toMap(new LinkedHashMap<>());
-    else if (v instanceof IteratorWriter) v = ((IteratorWriter) v).toList(new ArrayList<>());
+    else if (v instanceof IteratorWriter && maxDepth > 1) v = ((IteratorWriter) v).toList(new ArrayList<>());
-    else if (v instanceof Map) v = getDeepCopy((Map) v, maxDepth - 1, mutable);
+
+    if (v instanceof Map) v = getDeepCopy((Map) v, maxDepth - 1, mutable);
     else if (v instanceof Collection) v = getDeepCopy((Collection) v, maxDepth - 1, mutable);
     return v;
   }

solr/solrj/src/java/org/apache/solr/recipe/AddReplicaSuggester.java

@@ -20,21 +20,16 @@ package org.apache.solr.recipe;
 import java.util.Map;
 
 import org.apache.solr.common.util.Utils;
-import org.apache.solr.recipe.Policy.BaseSuggester;
+import org.apache.solr.recipe.Policy.Suggester;
-import org.apache.solr.recipe.Policy.Session;
 
 import static org.apache.solr.common.cloud.ZkStateReader.COLLECTION_PROP;
 import static org.apache.solr.common.cloud.ZkStateReader.SHARD_ID_PROP;
 import static org.apache.solr.common.params.CollectionParams.CollectionAction.ADDREPLICA;
 import static org.apache.solr.common.params.CoreAdminParams.NODE;
 
-class AddReplicaSuggester extends BaseSuggester {
+class AddReplicaSuggester extends Suggester {
 
-  AddReplicaSuggester(String coll, String shard, Session session) {
+  Map init() {
-    super(coll, shard, session);
-  }
-
-  Map get() {
     Map operation = tryEachNode(true);
     if (operation == null) operation = tryEachNode(false);
     return operation;
@@ -46,11 +41,12 @@ class AddReplicaSuggester extends BaseSuggester {
       Row row = matrix.get(i);
       row = row.addReplica(coll, shard);
       row.violations.clear();
-      for (Clause clause : session.getRuleSorter().clauses) {
+      for (Clause clause : session.getPolicy().clauses) {
         if (strict || clause.strict) clause.test(row);
       }
-      if (row.violations.isEmpty()) {
+      if (row.violations.isEmpty()) {// there are no rule violations
-        return Utils.makeMap("operation", ADDREPLICA,
+        matrix.set(i, matrix.get(i).addReplica(coll, shard));
+        return Utils.makeMap("operation", ADDREPLICA.toLower(),
             COLLECTION_PROP, coll,
             SHARD_ID_PROP, shard,
             NODE, row.node);

solr/solrj/src/java/org/apache/solr/recipe/Clause.java

@@ -27,7 +27,7 @@ import java.util.concurrent.atomic.AtomicReference;
 
 import org.apache.solr.common.MapWriter;
 import org.apache.solr.common.util.Utils;
-import org.apache.solr.recipe.Policy.ReplicaStat;
+import org.apache.solr.recipe.Policy.ReplicaInfo;
 
 import static java.util.Collections.singletonMap;
 import static org.apache.solr.common.params.CoreAdminParams.COLLECTION;
@@ -125,10 +125,10 @@ public class Clause implements MapWriter {
   TestStatus test(Row row) {
     AtomicReference<TestStatus> result = new AtomicReference<>(NOT_APPLICABLE);
 
-    for (Map.Entry<String, Map<String, List<ReplicaStat>>> colls : row.replicaInfo.entrySet()) {
+    for (Map.Entry<String, Map<String, List<ReplicaInfo>>> colls : row.replicaInfo.entrySet()) {
       if (!collection.isPass(colls.getKey()) || result.get() == FAIL) break;
       int count = 0;
-      for (Map.Entry<String, List<ReplicaStat>> shards : colls.getValue().entrySet()) {
+      for (Map.Entry<String, List<ReplicaInfo>> shards : colls.getValue().entrySet()) {
         if (!shard.isPass(shards.getKey()) || result.get() == FAIL) break;
         count += shards.getValue().size();
         if (shard.val.equals(EACH)) testReplicaCount(row, result, count);

solr/solrj/src/java/org/apache/solr/recipe/MoveReplicaSuggester.java

@@ -21,8 +21,7 @@ import java.util.Map;
 
 import org.apache.solr.common.util.Pair;
 import org.apache.solr.common.util.Utils;
-import org.apache.solr.recipe.Policy.BaseSuggester;
+import org.apache.solr.recipe.Policy.Suggester;
-import org.apache.solr.recipe.Policy.Session;
 
 import static org.apache.solr.common.cloud.ZkStateReader.COLLECTION_PROP;
 import static org.apache.solr.common.cloud.ZkStateReader.SHARD_ID_PROP;
@@ -30,13 +29,9 @@ import static org.apache.solr.common.params.CollectionParams.CollectionAction.MO
 import static org.apache.solr.common.params.CoreAdminParams.NODE;
 import static org.apache.solr.common.params.CoreAdminParams.REPLICA;
 
-public class MoveReplicaSuggester  extends BaseSuggester{
+public class MoveReplicaSuggester extends Suggester {
-
+  @Override
-  MoveReplicaSuggester(String coll, String shard, Session session) {
+  Map init() {
-    super(coll, shard, session);
-  }
-
-  Map get() {
     Map operation = tryEachNode(true);
     if (operation == null) operation = tryEachNode(false);
     return operation;
@@ -46,24 +41,27 @@ public class MoveReplicaSuggester  extends BaseSuggester{
     //iterate through elements and identify the least loaded
     for (int i = 0; i < matrix.size(); i++) {
       Row fromRow = matrix.get(i);
-      Pair<Row, Policy.ReplicaStat> pair = fromRow.removeReplica(coll, shard);
+      Pair<Row, Policy.ReplicaInfo> pair = fromRow.removeReplica(coll, shard);
       fromRow = pair.first();
       if(fromRow == null){
         //no such replica available
         continue;
       }
 
-      for (Clause clause : session.getRuleSorter().clauses) {
+      for (Clause clause : session.getPolicy().clauses) {
         if (strict || clause.strict) clause.test(fromRow);
       }
       if (fromRow.violations.isEmpty()) {
         for (int j = matrix.size() - 1; j > i; i--) {
           Row targetRow = matrix.get(i);
           targetRow = targetRow.addReplica(coll, shard);
-          for (Clause clause : session.getRuleSorter().clauses) {
+          targetRow.violations.clear();
+          for (Clause clause : session.getPolicy().clauses) {
             if (strict || clause.strict) clause.test(targetRow);
           }
           if (targetRow.violations.isEmpty()) {
+            matrix.set(i, matrix.get(i).removeReplica(coll, shard).first());
+            matrix.set(j, matrix.get(j).addReplica(coll, shard));
                 return Utils.makeMap("operation", MOVEREPLICA.toLower(),
                     COLLECTION_PROP, coll,
                     SHARD_ID_PROP, shard,

solr/solrj/src/java/org/apache/solr/recipe/Policy.java

@@ -28,6 +28,7 @@ import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.function.Supplier;
 import java.util.stream.Collectors;
 
 import org.apache.solr.common.MapWriter;
@@ -68,25 +69,35 @@ public class Policy {
 
   public class Session implements MapWriter {
     final List<String> nodes;
-    final NodeValueProvider snitch;
+    final ClusterDataProvider snitch;
     final List<Row> matrix;
     Set<String> collections = new HashSet<>();
 
-    Session(List<String> nodes, NodeValueProvider snitch) {
+    Session(List<String> nodes, ClusterDataProvider snitch, List<Row> matrix) {
       this.nodes = nodes;
       this.snitch = snitch;
+      this.matrix = matrix;
+    }
+
+    Session(ClusterDataProvider snitch) {
+      this.nodes = new ArrayList<>(snitch.getNodes());
+      this.snitch = snitch;
       matrix = new ArrayList<>(nodes.size());
       for (String node : nodes) matrix.add(new Row(node, params, snitch));
       for (Row row : matrix) row.replicaInfo.forEach((s, e) -> collections.add(s));
     }
 
+    Session copy() {
+      return new Session(nodes, snitch, getMatrixCopy());
+    }
+
     List<Row> getMatrixCopy() {
       return matrix.stream()
           .map(Row::copy)
           .collect(Collectors.toList());
     }
 
-    Policy getRuleSorter() {
+    Policy getPolicy() {
       return Policy.this;
 
     }
@@ -121,10 +132,10 @@ public class Policy {
           .collect(Collectors.toMap(r -> r.node, r -> r.violations));
     }
 
-    public Map suggest(CollectionAction action, String collection, String shard) {
+    public Suggester getSuggester(CollectionAction action, String collection, String shard) {
-      Suggester op = ops.get(action);
+      Suggester op = ops.get(action).get();
       if (op == null) throw new UnsupportedOperationException(action.toString() + "is not supported");
-      return op.suggest(collection, shard, this);
+      return op.init(collection, shard, this);
     }
 
     @Override
@@ -145,8 +156,8 @@ public class Policy {
   }
 
 
-  public Session createSession(List<String> nodes, NodeValueProvider snitch) {
+  public Session createSession(ClusterDataProvider snitch) {
-    return new Session(nodes, snitch);
+    return new Session(snitch);
   }
 
 
@@ -190,11 +201,11 @@ public class Policy {
   }
 
 
-  static class ReplicaStat implements MapWriter {
+  static class ReplicaInfo implements MapWriter {
     final String name;
     Map<String, Object> variables;
 
-    ReplicaStat(String name, Map<String, Object> vals) {
+    ReplicaInfo(String name, Map<String, Object> vals) {
       this.name = name;
       this.variables = vals;
     }
@@ -206,44 +217,51 @@ public class Policy {
   }
 
 
-  interface NodeValueProvider {
+  interface ClusterDataProvider {
-    Map<String, Object> getValues(String node, Collection<String> keys);
+    Map<String, Object> getNodeValues(String node, Collection<String> keys);
 
     /**
      * Get the details of each replica in a node. It attempts to fetch as much details about
-     * the replica as mentioned in the keys list
+     * the replica as mentioned in the keys list. It is not necessary to give al details
      * <p>
      * the format is {collection:shard :[{replicadetails}]}
      */
-    Map<String, Map<String, List<ReplicaStat>>> getReplicaCounts(String node, Collection<String> keys);
+    Map<String, Map<String, List<ReplicaInfo>>> getReplicaInfo(String node, Collection<String> keys);
+
+    Collection<String> getNodes();
   }
 
-  interface Suggester {
+  static abstract class Suggester {
-    Map<String, Object> suggest(String coll, String shard, Session session);
+    String coll;
-
+    String shard;
-  }
+    Policy.Session session;
-
-  static class BaseSuggester {
-    final String coll;
-    final String shard;
-    final Policy.Session session;
     List<Row> matrix;
 
-    BaseSuggester(String coll, String shard, Policy.Session session) {
+    Map operation;
+
+    Suggester init(String coll, String shard, Policy.Session session) {
       this.coll = coll;
       this.shard = shard;
-      this.session = session;
+      this.session = session.copy();
       matrix = session.getMatrixCopy();
+      this.operation = init();
+      return this;
     }
 
+    abstract Map init();
+
+
+    public Map getOperation() {
+      return operation;
+    }
 
   }
 
-  private static final Map<CollectionAction, Suggester> ops = new HashMap<>();
+  private static final Map<CollectionAction, Supplier<Suggester>> ops = new HashMap<>();
 
   static {
-    ops.put(CollectionAction.ADDREPLICA, (coll, shard, session) -> new AddReplicaSuggester(coll, shard, session).get());
+    ops.put(CollectionAction.ADDREPLICA, () -> new AddReplicaSuggester());
-    ops.put(CollectionAction.MOVEREPLICA, (coll, shard, session) -> new MoveReplicaSuggester(coll, shard, session).get());
+    ops.put(CollectionAction.MOVEREPLICA, () -> new MoveReplicaSuggester());
   }
 
 

solr/solrj/src/java/org/apache/solr/recipe/Row.java

@@ -23,12 +23,13 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Random;
 
 import org.apache.solr.common.IteratorWriter;
 import org.apache.solr.common.MapWriter;
 import org.apache.solr.common.util.Pair;
 import org.apache.solr.common.util.Utils;
-import org.apache.solr.recipe.Policy.ReplicaStat;
+import org.apache.solr.recipe.Policy.ReplicaInfo;
 
 import static org.apache.solr.common.params.CoreAdminParams.NODE;
 
@@ -36,16 +37,16 @@ import static org.apache.solr.common.params.CoreAdminParams.NODE;
 class Row implements MapWriter {
   public final String node;
   final Cell[] cells;
-  Map<String, Map<String, List<ReplicaStat>>> replicaInfo;
+  Map<String, Map<String, List<ReplicaInfo>>> replicaInfo;
   List<Clause> violations = new ArrayList<>();
   boolean anyValueMissing = false;
 
-  Row(String node, List<String> params, Policy.NodeValueProvider snitch) {
+  Row(String node, List<String> params, Policy.ClusterDataProvider snitch) {
-    replicaInfo = snitch.getReplicaCounts(node, params);
+    replicaInfo = snitch.getReplicaInfo(node, params);
     if (replicaInfo == null) replicaInfo = Collections.emptyMap();
     this.node = node;
     cells = new Cell[params.size()];
-    Map<String, Object> vals = snitch.getValues(node, params);
+    Map<String, Object> vals = snitch.getNodeValues(node, params);
     for (int i = 0; i < params.size(); i++) {
       String s = params.get(i);
       cells[i] = new Cell(i, s, vals.get(s));
@@ -54,7 +55,7 @@ class Row implements MapWriter {
     }
   }
 
-  Row(String node, Cell[] cells, boolean anyValueMissing, Map<String, Map<String, List<ReplicaStat>>> replicaInfo, List<Clause> violations) {
+  Row(String node, Cell[] cells, boolean anyValueMissing, Map<String, Map<String, List<ReplicaInfo>>> replicaInfo, List<Clause> violations) {
     this.node = node;
     this.cells = new Cell[cells.length];
     for (int i = 0; i < this.cells.length; i++) {
@@ -74,11 +75,11 @@ class Row implements MapWriter {
     });
   }
 
-  public Row copy() {
+  Row copy() {
-    return new Row(node, cells, anyValueMissing, Utils.getDeepCopy(replicaInfo, 2), new ArrayList<>(violations));
+    return new Row(node, cells, anyValueMissing, Utils.getDeepCopy(replicaInfo, 3), new ArrayList<>(violations));
   }
 
-  public Object getVal(String name) {
+  Object getVal(String name) {
     for (Cell cell : cells) if (cell.name.equals(name)) return cell.val;
     return null;
   }
@@ -90,20 +91,21 @@ class Row implements MapWriter {
 
   Row addReplica(String coll, String shard) {
     Row row = copy();
-    Map<String, List<ReplicaStat>> c = row.replicaInfo.get(coll);
+    Map<String, List<ReplicaInfo>> c = row.replicaInfo.get(coll);
     if (c == null) row.replicaInfo.put(coll, c = new HashMap<>());
-    List<ReplicaStat> s = c.get(shard);
+    List<ReplicaInfo> s = c.get(shard);
     if (s == null) c.put(shard, s = new ArrayList<>());
+    s.add(new ReplicaInfo(""+new Random().nextInt(10000)+10000 , new HashMap<>()));
     return row;
 
 
   }
 
-  Pair<Row, ReplicaStat> removeReplica(String coll, String shard) {
+  Pair<Row, ReplicaInfo> removeReplica(String coll, String shard) {
     Row row = copy();
-    Map<String, List<ReplicaStat>> c = row.replicaInfo.get(coll);
+    Map<String, List<ReplicaInfo>> c = row.replicaInfo.get(coll);
     if(c == null) return null;
-    List<ReplicaStat> s = c.get(shard);
+    List<ReplicaInfo> s = c.get(shard);
     if (s == null || s.isEmpty()) return null;
     return new Pair(row,s.remove(0));
 

solr/solrj/src/java/org/apache/solr/recipe/SolrClientClusterDataProvider.java

@@ -0,0 +1,71 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.solr.recipe;
+
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.solr.client.solrj.impl.CloudSolrClient.ClusterStateProvider;
+import org.apache.solr.common.cloud.ClusterState;
+import org.apache.solr.common.cloud.DocCollection;
+import org.apache.solr.recipe.Policy.ClusterDataProvider;
+import org.apache.solr.recipe.Policy.ReplicaInfo;
+
+public class SolrClientClusterDataProvider implements ClusterDataProvider {
+
+  private final ClusterStateProvider clusterStateProvider;
+  private final Map<String, Map<String, Map<String, List<ReplicaInfo>>>> data = new HashMap<>();
+
+  public SolrClientClusterDataProvider(ClusterStateProvider csp) {
+    this.clusterStateProvider = csp;
+    Map<String, ClusterState.CollectionRef> all = clusterStateProvider.getCollections();
+    all.forEach((collName, ref) -> {
+      DocCollection coll = ref.get();
+      if (coll == null) return;
+      coll.forEachReplica((shard, replica) -> {
+        Map<String, Map<String, List<ReplicaInfo>>> nodeData = data.get(replica.getNodeName());
+        if (nodeData == null) data.put(replica.getNodeName(), nodeData = new HashMap<>());
+        Map<String, List<ReplicaInfo>> collData = nodeData.get(collName);
+        if (collData == null) nodeData.put(collName, collData = new HashMap<>());
+        List<ReplicaInfo> replicas = collData.get(shard);
+        if (replicas == null) collData.put(shard, replicas = new ArrayList<>());
+        replicas.add(new ReplicaInfo(replica.getName(), new HashMap<>()));
+      });
+    });
+  }
+
+  @Override
+  public Map<String, Object> getNodeValues(String node, Collection<String> keys) {
+    //todo
+    return new HashMap<>();
+  }
+
+  @Override
+  public Map<String, Map<String, List<ReplicaInfo>>> getReplicaInfo(String node, Collection<String> keys) {
+    return data.get(node);//todo fill other details
+  }
+
+  @Override
+  public Collection<String> getNodes() {
+    return clusterStateProvider.liveNodes();
+  }
+}

solr/solrj/src/test/org/apache/solr/client/solrj/impl/CloudSolrClientCacheTest.java

@@ -34,6 +34,7 @@ import org.apache.http.NoHttpResponseException;
 import org.apache.solr.SolrTestCaseJ4;
 import org.apache.solr.client.solrj.request.UpdateRequest;
 import org.apache.solr.common.cloud.ClusterState;
+import org.apache.solr.common.cloud.ClusterState.CollectionRef;
 import org.apache.solr.common.cloud.DocCollection;
 import org.apache.solr.common.util.NamedList;
 import static org.mockito.Mockito.*;
@@ -118,10 +119,10 @@ public class CloudSolrClientCacheTest extends SolrTestCaseJ4 {
   }
 
   private CloudSolrClient.ClusterStateProvider getStateProvider(Set<String> livenodes,
-                                                                Map<String, ClusterState.CollectionRef> colls) {
+                                                                Map<String, CollectionRef> colls) {
     return new CloudSolrClient.ClusterStateProvider() {
       @Override
-      public ClusterState.CollectionRef getState(String collection) {
+      public CollectionRef getState(String collection) {
         return colls.get(collection);
       }
 
@@ -148,6 +149,11 @@ public class CloudSolrClientCacheTest extends SolrTestCaseJ4 {
       @Override
       public void connect() { }
 
+      @Override
+      public Map<String, CollectionRef> getCollections() {
+        return Collections.emptyMap();
+      }
+
       @Override
       public void close() throws IOException {
 

solr/solrj/src/test/org/apache/solr/recipe/TestPolicy.java

@@ -31,6 +31,8 @@ import org.apache.solr.SolrTestCaseJ4;
 import org.apache.solr.common.util.Utils;
 import org.apache.solr.common.util.ValidatingJsonMap;
 
+import static org.apache.solr.common.params.CollectionParams.CollectionAction.ADDREPLICA;
+
 public class TestPolicy extends SolrTestCaseJ4 {
 
   public void testOperands() {
@@ -47,10 +49,18 @@ public class TestPolicy extends SolrTestCaseJ4 {
     c = new Clause((Map<String, Object>) Utils.fromJSONString("{nodeRole:'!overseer'}"));
     assertTrue(c.tag.isPass("OVERSEER"));
     assertFalse(c.tag.isPass("overseer"));
-
-
   }
-  public void testRuleParsing() throws IOException {
+
+  public void testRow(){
+    Row row = new Row("nodex", new Cell[]{new Cell(0,"node", "nodex")}, false, new HashMap<>(), new ArrayList<>());
+    Row r1 = row.addReplica("c1", "s1");
+    Row r2 = r1.addReplica("c1", "s1");
+    assertEquals(1,r1.replicaInfo.get("c1").get("s1").size());
+    assertEquals(2,r2.replicaInfo.get("c1").get("s1").size());
+    assertTrue(r2.replicaInfo.get("c1").get("s1").get(0) instanceof Policy.ReplicaInfo);
+    assertTrue(r2.replicaInfo.get("c1").get("s1").get(1) instanceof Policy.ReplicaInfo);
+  }
+  public void testRules() throws IOException {
     String rules = "{" +
         "conditions:[{nodeRole:'!overseer', strict:false},{replica:'<1',node:node3}," +
         "{replica:'<2',node:'#ANY', shard:'#EACH'}]," +
@@ -115,17 +125,22 @@ public class TestPolicy extends SolrTestCaseJ4 {
 
     Policy policy = new Policy((Map<String, Object>) Utils.fromJSONString(rules));
     Policy.Session session;
-    Policy.NodeValueProvider snitch = new Policy.NodeValueProvider() {
+    Policy.ClusterDataProvider snitch = new Policy.ClusterDataProvider() {
       @Override
-      public Map<String,Object> getValues(String node, Collection<String> keys) {
+      public Map<String,Object> getNodeValues(String node, Collection<String> keys) {
         Map<String,Object> result = new LinkedHashMap<>();
         keys.stream().forEach(s -> result.put(s, nodeValues.get(node).get(s)));
         return result;
       }
 
       @Override
-      public Map<String, Map<String, List<Policy.ReplicaStat>>> getReplicaCounts(String node, Collection<String> keys) {
+      public Collection<String> getNodes() {
-        Map<String, Map<String, List<Policy.ReplicaStat>>> result = new LinkedHashMap<>();
+        return Arrays.asList("node1", "node2", "node3", "node4");
+      }
+
+      @Override
+      public Map<String, Map<String, List<Policy.ReplicaInfo>>> getReplicaInfo(String node, Collection<String> keys) {
+        Map<String, Map<String, List<Policy.ReplicaInfo>>> result = new LinkedHashMap<>();
 
         m.forEach((collName, o) -> {
           ValidatingJsonMap coll = (ValidatingJsonMap) o;
@@ -135,11 +150,11 @@ public class TestPolicy extends SolrTestCaseJ4 {
               ValidatingJsonMap r = (ValidatingJsonMap) o2;
               String node_name = (String) r.get("node_name");
               if (!node_name.equals(node)) return;
-              Map<String, List<Policy.ReplicaStat>> shardVsReplicaStats = result.get(collName);
+              Map<String, List<Policy.ReplicaInfo>> shardVsReplicaStats = result.get(collName);
               if (shardVsReplicaStats == null) result.put(collName, shardVsReplicaStats = new HashMap<>());
-              List<Policy.ReplicaStat> replicaStats = shardVsReplicaStats.get(shard);
+              List<Policy.ReplicaInfo> replicaInfos = shardVsReplicaStats.get(shard);
-              if (replicaStats == null) shardVsReplicaStats.put(shard, replicaStats = new ArrayList<>());
+              if (replicaInfos == null) shardVsReplicaStats.put(shard, replicaInfos = new ArrayList<>());
-              replicaStats.add(new Policy.ReplicaStat(replicaName, new HashMap<>()));
+              replicaInfos.add(new Policy.ReplicaInfo(replicaName, new HashMap<>()));
             });
           });
         });
@@ -150,7 +165,7 @@ public class TestPolicy extends SolrTestCaseJ4 {
 
     };
 
-    session = policy.createSession(Arrays.asList("node1", "node2", "node3", "node4"), snitch);
+    session = policy.createSession( snitch);
 
     session.applyRules();
     List<Row> l = session.getSorted();
@@ -177,6 +192,11 @@ public class TestPolicy extends SolrTestCaseJ4 {
     assertEquals(v.get(0).replica.val, 1);
     assertEquals(v.get(0).tag.val, "node3");
 
+    Policy.Suggester suggester = session.getSuggester(ADDREPLICA, "gettingstarted", "r1");
+    Map operation = suggester.getOperation();
+    assertEquals("node2", operation.get("node"));
+    System.out.println(Utils.toJSONString(operation));
+
 
 
   }