From c95f5900acb0645a78ae94c1d8113e6ad4446fe5 Mon Sep 17 00:00:00 2001
From: Mark Robert Miller <markrmiller@apache.org>
Date: Sun, 24 Nov 2013 20:19:43 +0000
Subject: [PATCH] SOLR-4553: Bug in finding remote node when proxying update
 request in a cluster with more than one collection. Also, attempt to proxy
 requests more aggressively.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1545065 13f79535-47bb-0310-9956-ffa450edef68
---
 .../solr/servlet/SolrDispatchFilter.java      | 44 ++++++++++++++++---
 1 file changed, 37 insertions(+), 7 deletions(-)

diff --git a/solr/core/src/java/org/apache/solr/servlet/SolrDispatchFilter.java b/solr/core/src/java/org/apache/solr/servlet/SolrDispatchFilter.java
index 4c454ec5fa7..756ddb49855 100644
--- a/solr/core/src/java/org/apache/solr/servlet/SolrDispatchFilter.java
+++ b/solr/core/src/java/org/apache/solr/servlet/SolrDispatchFilter.java
@@ -574,13 +574,14 @@ public class SolrDispatchFilter implements Filter
     ClusterState clusterState = cores.getZkController().getClusterState();
     Collection<Slice> slices = clusterState.getActiveSlices(collectionName);
     boolean byCoreName = false;
+    
     if (slices == null) {
+      slices = new ArrayList<Slice>();
       // look by core name
       byCoreName = true;
-      Set<String> collections = clusterState.getCollections();
-      for (String collection : collections) {
-        slices = new ArrayList<Slice>();
-        slices.addAll(clusterState.getSlices(collection));
+      slices = getSlicesForCollections(clusterState, slices, true);
+      if (slices == null || slices.size() == 0) {
+        slices = getSlicesForCollections(clusterState, slices, false);
       }
     }
     
@@ -588,6 +589,21 @@ public class SolrDispatchFilter implements Filter
       return null;
     }
     
+    String coreUrl = getCoreUrl(cores, collectionName, origCorename, clusterState,
+        slices, byCoreName, true);
+    
+    if (coreUrl == null) {
+      coreUrl = getCoreUrl(cores, collectionName, origCorename, clusterState,
+          slices, byCoreName, false);
+    }
+    
+    return coreUrl;
+  }
+
+  private String getCoreUrl(CoreContainer cores, String collectionName,
+      String origCorename, ClusterState clusterState, Collection<Slice> slices,
+      boolean byCoreName, boolean activeReplicas) {
+    String coreUrl;
     Set<String> liveNodes = clusterState.getLiveNodes();
     Iterator<Slice> it = slices.iterator();
     while (it.hasNext()) {
@@ -595,8 +611,9 @@ public class SolrDispatchFilter implements Filter
       Map<String,Replica> sliceShards = slice.getReplicasMap();
       for (ZkNodeProps nodeProps : sliceShards.values()) {
         ZkCoreNodeProps coreNodeProps = new ZkCoreNodeProps(nodeProps);
-        if (liveNodes.contains(coreNodeProps.getNodeName())
-            && coreNodeProps.getState().equals(ZkStateReader.ACTIVE)) {
+        if (!activeReplicas || (liveNodes.contains(coreNodeProps.getNodeName())
+            && coreNodeProps.getState().equals(ZkStateReader.ACTIVE))) {
+
           if (byCoreName && !collectionName.equals(coreNodeProps.getCoreName())) {
             // if it's by core name, make sure they match
             continue;
@@ -605,7 +622,7 @@ public class SolrDispatchFilter implements Filter
             // don't count a local core
             continue;
           }
-          String coreUrl;
+
           if (origCorename != null) {
             coreUrl = coreNodeProps.getBaseUrl() + "/" + origCorename;
           } else {
@@ -621,6 +638,19 @@ public class SolrDispatchFilter implements Filter
     }
     return null;
   }
+
+  private Collection<Slice> getSlicesForCollections(ClusterState clusterState,
+      Collection<Slice> slices, boolean activeSlices) {
+    Set<String> collections = clusterState.getCollections();
+    for (String collection : collections) {
+      if (activeSlices) {
+        slices.addAll(clusterState.getActiveSlices(collection));
+      } else {
+        slices.addAll(clusterState.getSlices(collection));
+      }
+    }
+    return slices;
+  }
   
   private SolrCore getCoreByCollection(CoreContainer cores, String corename, String path) {
     String collection = corename;