Bind index versions dynamically

We want to support a single index version for reading and multiple
index versions for writing. Wrap these in an IndexCollection with
getSearchIndex and getWriteIndexes methods. Still bind a single
implementation at startup.

Change-Id: Ibc4dbbeba064cde68f2585126d7708db5a2b3410

gerrit-solr/src/main/java/com/google/gerrit/solr/SolrChangeIndex.java

@@ -34,6 +34,7 @@ import com.google.gerrit.server.index.ChangeIndex;
 import com.google.gerrit.server.index.FieldDef;
 import com.google.gerrit.server.index.FieldDef.FillArgs;
 import com.google.gerrit.server.index.FieldType;
+import com.google.gerrit.server.index.IndexCollection;
 import com.google.gerrit.server.index.IndexRewriteImpl;
 import com.google.gerrit.server.index.Schema;
 import com.google.gerrit.server.query.Predicate;
@@ -74,6 +75,7 @@ class SolrChangeIndex implements ChangeIndex, LifecycleListener {
 
   private final FillArgs fillArgs;
   private final SitePaths sitePaths;
+  private final IndexCollection indexes;
   private final CloudSolrServer openIndex;
   private final CloudSolrServer closedIndex;
   private final Schema<ChangeData> schema;
@@ -82,9 +84,11 @@ class SolrChangeIndex implements ChangeIndex, LifecycleListener {
       @GerritServerConfig Config cfg,
       FillArgs fillArgs,
       SitePaths sitePaths,
+      IndexCollection indexes,
       Schema<ChangeData> schema) throws IOException {
     this.fillArgs = fillArgs;
     this.sitePaths = sitePaths;
+    this.indexes = indexes;
     this.schema = schema;
 
     String url = cfg.getString("index", "solr", "url");
@@ -101,7 +105,8 @@ class SolrChangeIndex implements ChangeIndex, LifecycleListener {
 
   @Override
   public void start() {
-    // Do nothing.
+    indexes.setSearchIndex(this);
+    indexes.addWriteIndex(this);
   }
 
   @Override
@@ -110,6 +115,11 @@ class SolrChangeIndex implements ChangeIndex, LifecycleListener {
     closedIndex.shutdown();
   }
 
+  @Override
+  public Schema<ChangeData> getSchema() {
+    return schema;
+  }
+
   @Override
   public ListenableFuture<Void> insert(ChangeData cd) throws IOException {
     String id = cd.getId().toString();

gerrit-solr/src/main/java/com/google/gerrit/solr/SolrIndexModule.java

@@ -15,8 +15,19 @@
 package com.google.gerrit.solr;
 
 import com.google.gerrit.lifecycle.LifecycleModule;
+import com.google.gerrit.server.config.GerritServerConfig;
+import com.google.gerrit.server.config.SitePaths;
 import com.google.gerrit.server.index.ChangeIndex;
+import com.google.gerrit.server.index.ChangeSchemas;
+import com.google.gerrit.server.index.FieldDef.FillArgs;
+import com.google.gerrit.server.index.IndexCollection;
 import com.google.gerrit.server.index.IndexModule;
+import com.google.inject.Provides;
+import com.google.inject.Singleton;
+
+import org.eclipse.jgit.lib.Config;
+
+import java.io.IOException;
 
 public class SolrIndexModule extends LifecycleModule {
   private final boolean checkVersion;
@@ -40,4 +51,14 @@ public class SolrIndexModule extends LifecycleModule {
       listener().to(IndexVersionCheck.class);
     }
   }
+
+  @Provides
+  @Singleton
+  public SolrChangeIndex getChangeIndex(@GerritServerConfig Config cfg,
+      SitePaths sitePaths,
+      IndexCollection indexes,
+      FillArgs fillArgs) throws IOException {
+    return new SolrChangeIndex(cfg, fillArgs, sitePaths, indexes,
+        ChangeSchemas.getLatestRelease());
+  }
 }