SOLR-15011: /admin/logging now distributes setLevel to all nodes (#2230)

The admin UI will set nodes=all for this.

Co-authored-by: Nazerke Seidan <nseidan@salesforce.com>
Co-authored-by: David Smiley <dsmiley@apache.org>

solr/CHANGES.txt

@@ -72,6 +72,9 @@ Improvements
 * SOLR-14949: Docker: Ability to customize the FROM image when building.
   (Houston Putman)
 
+* SOLR-15011: /admin/logging handler will now propagate setLevel (log threshold) to all nodes
+when told to. The admin UI now tells it to. (Nazerke Seidan, David Smiley)
+
 Other Changes
 ----------------------
 * SOLR-14656: Autoscaling framework removed (Ishan Chattopadhyaya, noble, Ilan Ginzburg)

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

@@ -111,8 +111,8 @@ public class AdminHandlersProxy {
         log.warn("Timeout when fetching result from node {}", entry.getKey(), te);
       }
     }
-    if (log.isInfoEnabled()) {
-      log.info("Fetched response from {} nodes: {}", responses.keySet().size(), responses.keySet());
+    if (log.isDebugEnabled()) {
+      log.debug("Fetched response from {} nodes: {}", responses.keySet().size(), responses.keySet());
     }
     return true;
   } 

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

@@ -49,13 +49,15 @@ public class LoggingHandler extends RequestHandlerBase implements SolrCoreAware
 
   @SuppressWarnings({"rawtypes"})
   private LogWatcher watcher;
+  private final CoreContainer cc;
   
   public LoggingHandler(CoreContainer cc) {
+    this.cc = cc;
     this.watcher = cc.getLogging();
   }
   
   public LoggingHandler() {
-    
+    this.cc = null;
   }
   
   @Override
@@ -151,6 +153,9 @@ public class LoggingHandler extends RequestHandlerBase implements SolrCoreAware
       rsp.add("loggers", info);
     }
     rsp.setHttpCaching(false);
+    if (cc != null && AdminHandlersProxy.maybeProxyToNodes(req, rsp, cc)) {
+      return; // Request was proxied to other node
+    }
   }
 
   // ////////////////////// SolrInfoMBeans methods //////////////////////

solr/core/src/test/org/apache/solr/handler/admin/AdminHandlersProxyTest.java

@@ -18,6 +18,7 @@
 package org.apache.solr.handler.admin;
 
 import java.io.IOException;
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Set;
 import java.util.concurrent.TimeUnit;
@@ -27,12 +28,17 @@ import org.apache.lucene.util.IOUtils;
 import org.apache.solr.client.solrj.SolrRequest;
 import org.apache.solr.client.solrj.SolrServerException;
 import org.apache.solr.client.solrj.impl.CloudSolrClient;
+import org.apache.solr.client.solrj.request.CollectionAdminRequest;
 import org.apache.solr.client.solrj.request.GenericSolrRequest;
+import org.apache.solr.client.solrj.response.QueryResponse;
 import org.apache.solr.client.solrj.response.SimpleSolrResponse;
 import org.apache.solr.cloud.SolrCloudTestCase;
 import org.apache.solr.common.SolrException;
+import org.apache.solr.common.params.CommonParams;
 import org.apache.solr.common.params.MapSolrParams;
+import org.apache.solr.common.params.ModifiableSolrParams;
 import org.apache.solr.common.util.NamedList;
+import org.apache.solr.common.util.SimpleOrderedMap;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.BeforeClass;
@@ -91,6 +97,32 @@ public class AdminHandlersProxyTest extends SolrCloudTestCase {
     assertNotNull(((NamedList)nl.get(nl.getName(1))).get("metrics"));
   }
 
+  @Test
+  public void proxyLoggingHandlerAllNodes() throws IOException, SolrServerException {
+    CollectionAdminRequest.createCollection("collection", "conf", 2, 2).process(solrClient);
+    ModifiableSolrParams mparams = new ModifiableSolrParams();
+
+    mparams.set(CommonParams.QT, "/admin/logging");
+    mparams.set("nodes", "all");
+    mparams.set("set", "com.codahale.metrics.jmx.JmxReporter:WARN");
+    solrClient.query("collection", mparams, SolrRequest.METHOD.GET);
+
+    Set<String> nodes = solrClient.getClusterStateProvider().getLiveNodes();
+    nodes.forEach(node -> {
+      mparams.clear();
+      mparams.set(CommonParams.QT, "/admin/logging");
+      mparams.set("nodes", node);
+      QueryResponse rsp = null;
+      try {
+        rsp = solrClient.query("collection", mparams, SolrRequest.METHOD.GET);
+      } catch (Exception e) {
+        fail("Exception while proxying request to node " + node);
+      }
+      NamedList<Object> nl = rsp.getResponse();
+      assertEquals("WARN", ((SimpleOrderedMap) ((ArrayList)nl.get("loggers")).get(5)).get("level"));
+    });
+  }
+
   @Test(expected = SolrException.class)
   public void proxySystemInfoHandlerNonExistingNode() throws IOException, SolrServerException {
     MapSolrParams params = new MapSolrParams(Collections.singletonMap("nodes", "example.com:1234_solr"));

solr/solr-ref-guide/src/configuring-logging.adoc

@@ -38,6 +38,7 @@ When you select **Level**, you see the following menu:
 image::images/logging/level_menu.png[image,width=1159,height=577]
 
 Directories are shown with their current logging levels. The Log Level Menu floats over these. To set a log level for a particular directory, select it and click the appropriate log level button.
+The log level change will be distributed to all nodes in the cluster.
 
 Log levels settings are as follows:
 

solr/webapp/web/js/angular/services.js

@@ -61,7 +61,7 @@ solrAdminServices.factory('System',
     return $resource('admin/info/logging', {'wt':'json', '_':Date.now()}, {
       "events": {params: {since:'0'}},
       "levels": {},
-      "setLevel": {}
+      "setLevel": {params: {nodes:'all'}}
       });
   }])
 .factory('Zookeeper',