SOLR-17884: Don't depend on Apache HttpClient (#3792)

* ZkController.  Unfortunately using longer connection timeout (30 not 8) but at least now we re-use an internal client; get listeners for observability & security.
* SolrJ ConcurrentUpdateHttp2SolrClient (jetty).  Used an inner class of a deprecated client.
* solrj-streaming DatabaseMetaDataImpl

Author: dsmiley

solr/core/src/java/org/apache/solr/cloud/ZkController.java

@@ -62,7 +62,7 @@
 import org.apache.solr.client.solrj.cloud.SolrCloudManager;
 import org.apache.solr.client.solrj.impl.CloudHttp2SolrClient;
 import org.apache.solr.client.solrj.impl.CloudSolrClient;
-import org.apache.solr.client.solrj.impl.HttpSolrClient.Builder;
+import org.apache.solr.client.solrj.impl.Http2SolrClient;
 import org.apache.solr.client.solrj.impl.SolrClientCloudManager;
 import org.apache.solr.client.solrj.impl.SolrZkClientTimeout;
 import org.apache.solr.client.solrj.impl.ZkClientClusterStateProvider;
@@ -2306,12 +2306,13 @@ private ZkCoreNodeProps waitForLeaderToSeeDownState(
         }
 
         // short timeouts, we may be in a storm and this is just best effort, and maybe we should be
-        // the
-        // leader now
+        // the leader now
+        // TODO ideally want 8sec connection timeout but can't easily also share the client
+        // listeners
         try (SolrClient client =
-            new Builder(leaderBaseUrl)
-                .withConnectionTimeout(8000, TimeUnit.MILLISECONDS)
-                .withSocketTimeout(30000, TimeUnit.MILLISECONDS)
+            new Http2SolrClient.Builder(leaderBaseUrl)
+                .withHttpClient(getCoreContainer().getDefaultHttpSolrClient())
+                .withIdleTimeout(30000, TimeUnit.MILLISECONDS)
                 .build()) {
           WaitForState prepCmd = new WaitForState();
           prepCmd.setCoreName(leaderCoreName);

solr/solrj-streaming/src/java/org/apache/solr/client/solrj/io/sql/DatabaseMetaDataImpl.java

@@ -28,7 +28,7 @@
 import org.apache.solr.client.solrj.SolrQuery;
 import org.apache.solr.client.solrj.SolrServerException;
 import org.apache.solr.client.solrj.impl.CloudSolrClient;
-import org.apache.solr.client.solrj.impl.HttpSolrClient.Builder;
+import org.apache.solr.client.solrj.impl.Http2SolrClient;
 import org.apache.solr.client.solrj.response.QueryResponse;
 import org.apache.solr.common.cloud.ClusterState;
 import org.apache.solr.common.util.SimpleOrderedMap;
@@ -124,7 +124,7 @@ public String getDatabaseProductVersion() throws SQLException {
     for (String node : liveNodes) {
       try {
         String nodeURL = Utils.getBaseUrlForNodeName(node, urlScheme);
-        solrClient = new Builder(nodeURL).build();
+        solrClient = new Http2SolrClient.Builder(nodeURL).build();
 
         QueryResponse rsp = solrClient.query(sysQuery);
         return String.valueOf(

solr/solrj/src/java/org/apache/solr/client/solrj/impl/ConcurrentUpdateHttp2SolrClient.java

@@ -32,7 +32,6 @@
 import org.apache.solr.client.solrj.SolrClient;
 import org.apache.solr.client.solrj.SolrRequest;
 import org.apache.solr.client.solrj.SolrServerException;
-import org.apache.solr.client.solrj.impl.ConcurrentUpdateSolrClient.Update;
 import org.apache.solr.client.solrj.request.UpdateRequest;
 import org.apache.solr.client.solrj.util.ClientUtils;
 import org.apache.solr.common.SolrException;
@@ -177,6 +176,9 @@ protected ConcurrentUpdateHttp2SolrClient(Builder builder) {
     // processedCount is now managed by StallDetection
   }
 
+  /** Class representing an UpdateRequest and an optional collection. */
+  private record Update(UpdateRequest request, String collection) {}
+
   /** Opens a connection and sends everything... */
   class Runner implements Runnable {
 
@@ -237,16 +239,16 @@ void sendUpdateStream() throws Exception {
 
             InputStreamResponseListener responseListener = null;
             try (Http2SolrClient.OutStream out =
-                client.initOutStream(basePath, update.getRequest(), update.getCollection())) {
+                client.initOutStream(basePath, update.request(), update.collection())) {
               Update upd = update;
               while (upd != null) {
-                UpdateRequest req = upd.getRequest();
-                if (!out.belongToThisStream(req, upd.getCollection())) {
+                UpdateRequest req = upd.request();
+                if (!out.belongToThisStream(req, upd.collection())) {
                   // Request has different params or destination core/collection, return to queue
                   queue.add(upd);
                   break;
                 }
-                client.send(out, upd.getRequest(), upd.getCollection());
+                client.send(out, upd.request(), upd.collection());
                 out.flush();
 
                 notifyQueueAndRunnersIfEmptyQueue();