From 1123afae94f36027bcb7b2dc40b089653ed4d1c8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan=20H=C3=B8ydahl?= <janhoy@apache.org>
Date: Fri, 2 Aug 2019 13:01:20 +0200
Subject: [PATCH] SOLR-13672: Cloud -> Zk Status page now parses response from
 Zookeeper 3.5.5 correctly

---
 solr/CHANGES.txt                              |  2 +
 .../handler/admin/ZookeeperStatusHandler.java | 40 +++++++++++--------
 2 files changed, 25 insertions(+), 17 deletions(-)

diff --git a/solr/CHANGES.txt b/solr/CHANGES.txt
index 03279b7a3e8..b6dd4401db2 100644
--- a/solr/CHANGES.txt
+++ b/solr/CHANGES.txt
@@ -126,6 +126,8 @@ Bug Fixes
 * SOLR-13664: Fixed SolrTestCaseJ4.deleteCore() to properly reset the dataDir used by initCore()
   (hossman)
 
+* SOLR-13672: Cloud -> Zk Status page now parses response from Zookeeper 3.5.5 correctly (Jörn Franke, janhoy)
+
 Other Changes
 ----------------------
 
diff --git a/solr/core/src/java/org/apache/solr/handler/admin/ZookeeperStatusHandler.java b/solr/core/src/java/org/apache/solr/handler/admin/ZookeeperStatusHandler.java
index 7afd6bf6dc1..fc42f18f9ee 100644
--- a/solr/core/src/java/org/apache/solr/handler/admin/ZookeeperStatusHandler.java
+++ b/solr/core/src/java/org/apache/solr/handler/admin/ZookeeperStatusHandler.java
@@ -99,6 +99,9 @@ public final class ZookeeperStatusHandler extends RequestHandlerBase {
     for (String zk : zookeepers) {
       try {
         Map<String, Object> stat = monitorZookeeper(zk);
+        if (stat.containsKey("errors")) {
+          errors.addAll((List<String>)stat.get("errors"));
+        }
         details.add(stat);
         if ("true".equals(String.valueOf(stat.get("ok")))) {
           numOk++;
@@ -115,13 +118,12 @@ public final class ZookeeperStatusHandler extends RequestHandlerBase {
       } catch (SolrException se) {
         log.warn("Failed talking to zookeeper" + zk, se);
         errors.add(se.getMessage());
-        zkStatus.put("errors", errors);
         Map<String, Object> stat = new HashMap<>();
         stat.put("host", zk);
         stat.put("ok", false);
-        zkStatus.put("status", STATUS_YELLOW);
-        return zkStatus;
-      }       
+        status = STATUS_YELLOW;
+        details.add(stat);
+      }
     }
     zkStatus.put("details", details);
     if (followers+leaders > 0 && standalone > 0) {
@@ -180,36 +182,34 @@ public final class ZookeeperStatusHandler extends RequestHandlerBase {
 
   private Map<String, Object> monitorZookeeper(String zkHostPort) throws SolrException {
     Map<String, Object> obj = new HashMap<>();
+    List<String> errors = new ArrayList<>();
     obj.put("host", zkHostPort);
     List<String> lines = getZkRawResponse(zkHostPort, "ruok");
     boolean ok = "imok".equals(lines.get(0));
-    if (ok == false) {
-      log.warn("Check 4lw.commands.whitelist setting in zookeeper configuration file, ZK response {}", lines.get(0));
-      throw new SolrException(SolrException.ErrorCode.SERVER_ERROR, lines.get(0) + " Check 4lw.commands.whitelist setting in zookeeper configuration file.");
-    }
     obj.put("ok", ok);
     lines = getZkRawResponse(zkHostPort, "mntr");
-    String[] parts;
     for (String line : lines) {
-      parts = line.split("\t");
+      String[] parts = line.split("\t");
       if (parts.length >= 2) {
         obj.put(parts[0], parts[1]);
       } else {
-        log.warn("Check 4lw.commands.whitelist setting in zookeeper configuration file, ZK response {}", line);
-        throw new SolrException(SolrException.ErrorCode.SERVER_ERROR, line + " Check 4lw.commands.whitelist setting in zookeeper configuration file.");
+        String err = String.format("Unexpected line in 'mntr' response from Zookeeper %s: %s", zkHostPort, line);
+        log.warn(err);
+        errors.add(err);
       }
     }
     lines = getZkRawResponse(zkHostPort, "conf");
-
     for (String line : lines) {
-      parts = line.split("=");
+      String[] parts = line.split("=");
       if (parts.length >= 2) {
         obj.put(parts[0], parts[1]);
-      } else {
-        log.warn("Check 4lw.commands.whitelist setting in zookeeper configuration file, ZK response {}", line);
-        throw new SolrException(SolrException.ErrorCode.SERVER_ERROR, line + " Check 4lw.commands.whitelist setting in zookeeper configuration file.");
+      } else if (!line.startsWith("membership:")) {
+        String err = String.format("Unexpected line in 'conf' response from Zookeeper %s: %s", zkHostPort, line);
+        log.warn(err);
+        errors.add(err);
       }
     }
+    obj.put("errors", errors);
     return obj;
   }
   
@@ -238,6 +238,12 @@ public final class ZookeeperStatusHandler extends RequestHandlerBase {
       if (response == null || response.isEmpty()) {
         throw new SolrException(SolrException.ErrorCode.SERVER_ERROR, "Empty response from Zookeeper " + zkHostPort);
       }
+      if (response.size() == 1 && response.get(0).contains("not in the whitelist")) {
+        throw new SolrException(SolrException.ErrorCode.SERVER_ERROR, "Could not execute " + fourLetterWordCommand +
+            " towards ZK host " + zkHostPort + ". Add this line to the 'zoo.cfg' " +
+            "configuration file on each zookeeper node: '4lw.commands.whitelist=mntr,conf,ruok'. See also chapter " +
+            "'Setting Up an External ZooKeeper Ensemble' in the Solr Reference Guide.");
+      }
       return response;
     } catch (IOException e) {
       throw new SolrException(SolrException.ErrorCode.SERVER_ERROR, "Failed talking to Zookeeper " + zkHostPort, e);