Control which plugins will be auto installed on auto init

Use the system property 'gerrit.install_plugins' to control which
of the packaged plugins will be installed during auto site init
in a servlet container.

When 'gerrit.install_plugins' property is not defined then all packaged
plugins will be installed. If it is present then it is parsed as a
comma separated list of plugin names to install. Defining an empty
string as the property value means that no plugin will be installed.

Change-Id: I52881c9677bc9cc1e51c46c2c2ce4558c79b9a3e

Documentation/config-auto-site-initialization.txt

@@ -4,9 +4,11 @@
 
 Gerrit supports automatic site initialization on server startup
 when Gerrit runs in a servlet container. Both creation of a new site
-and upgrade of an existing site are supported.  All packaged plugins
-will be installed when Gerrit is deployed in a servlet container and the
-location of the Gerrit distribution can be determined at runtime.
+and upgrade of an existing site are supported. By default, all packaged
+plugins will be installed when Gerrit is deployed in a servlet container
+and the location of the Gerrit distribution can be determined at
+runtime. It is also possible to install only a subset of packaged
+plugins or not install any plugin.
 
 This feature may be useful for such setups where Gerrit administrators
 don't have direct access to the database and the file system of the
@@ -50,6 +52,11 @@ creation). In order to auto initialize Gerrit with an embedded H2
 database use the `gerrit.site_path` to define the location of the review
 site and don't define a JNDI resource with a URL under that path.
 
+If the 'gerrit.install_plugins' property is not defined then all packaged
+plugins will be installed. If it is defined then it is parsed as a
+comma separated list of plugin names to install. If the value is an
+empty string then no plugin will be installed.
+
 === Example 1
 
 Prepare Tomcat so that a site is initialized at a given path using

gerrit-pgm/src/main/java/com/google/gerrit/pgm/BaseInit.java

@@ -54,6 +54,8 @@ import org.slf4j.LoggerFactory;
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Iterator;
 import java.util.List;
 
 import javax.sql.DataSource;
@@ -66,25 +68,29 @@ public class BaseInit extends SiteProgram {
   private final boolean standalone;
   private final boolean initDb;
   protected final PluginsDistribution pluginsDistribution;
+  private final List<String> pluginsToInstall;
 
-  protected BaseInit(PluginsDistribution pluginsDistribution) {
+  protected BaseInit(PluginsDistribution pluginsDistribution,
+      List<String> pluginsToInstall) {
     this.standalone = true;
     this.initDb = true;
     this.pluginsDistribution = pluginsDistribution;
+    this.pluginsToInstall = pluginsToInstall;
   }
 
   public BaseInit(File sitePath, boolean standalone, boolean initDb,
-      PluginsDistribution pluginsDistribution) {
-    this(sitePath, null, standalone, initDb, pluginsDistribution);
+      PluginsDistribution pluginsDistribution, List<String> pluginsToInstall) {
+    this(sitePath, null, standalone, initDb, pluginsDistribution, pluginsToInstall);
   }
 
   public BaseInit(File sitePath, final Provider<DataSource> dsProvider,
       boolean standalone, boolean initDb,
-      PluginsDistribution pluginsDistribution) {
+      PluginsDistribution pluginsDistribution, List<String> pluginsToInstall) {
     super(sitePath, dsProvider);
     this.standalone = standalone;
     this.initDb = initDb;
     this.pluginsDistribution = pluginsDistribution;
+    this.pluginsToInstall = pluginsToInstall;
   }
 
   @Override
@@ -136,7 +142,19 @@ public class BaseInit extends SiteProgram {
 
   protected List<String> getInstallPlugins() {
     try {
-      return pluginsDistribution.listPluginNames();
+      if (pluginsToInstall != null && pluginsToInstall.isEmpty()) {
+        return Collections.emptyList();
+      }
+      List<String> names = pluginsDistribution.listPluginNames();
+      if (pluginsToInstall != null) {
+        for (Iterator<String> i = names.iterator(); i.hasNext();) {
+          String n = i.next();
+          if (!pluginsToInstall.contains(n)) {
+            i.remove();
+          }
+        }
+      }
+      return names;
     } catch (FileNotFoundException e) {
       log.warn("Couldn't find distribution archive location."
           + " No plugin will be installed");

gerrit-pgm/src/main/java/com/google/gerrit/pgm/Init.java

@@ -60,11 +60,11 @@ public class Init extends BaseInit {
   Browser browser;
 
   public Init() {
-    super(new WarDistribution());
+    super(new WarDistribution(), null);
   }
 
   public Init(File sitePath) {
-    super(sitePath, true, true, new WarDistribution());
+    super(sitePath, true, true, new WarDistribution(), null);
     batchMode = true;
     noAutoStart = true;
   }

gerrit-war/src/main/java/com/google/gerrit/httpd/SiteInitializer.java

@@ -25,6 +25,7 @@ import java.sql.Connection;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.sql.Statement;
+import java.util.List;
 
 public final class SiteInitializer {
   private static final Logger LOG = LoggerFactory
@@ -33,12 +34,14 @@ public final class SiteInitializer {
   private final String sitePath;
   private final String initPath;
   private final PluginsDistribution pluginsDistribution;
+  private final List<String> pluginsToInstall;
 
   SiteInitializer(String sitePath, String initPath,
-      PluginsDistribution pluginsDistribution) {
+      PluginsDistribution pluginsDistribution, List<String> pluginsToInstall) {
     this.sitePath = sitePath;
     this.initPath = initPath;
     this.pluginsDistribution = pluginsDistribution;
+    this.pluginsToInstall = pluginsToInstall;
   }
 
   public void init() {
@@ -47,7 +50,7 @@ public final class SiteInitializer {
         File site = new File(sitePath);
         LOG.info(String.format("Initializing site at %s",
             site.getAbsolutePath()));
-        new BaseInit(site, false, true, pluginsDistribution).run();
+        new BaseInit(site, false, true, pluginsDistribution, pluginsToInstall).run();
         return;
       }
 
@@ -61,7 +64,7 @@ public final class SiteInitializer {
           LOG.info(String.format("Initializing site at %s",
               site.getAbsolutePath()));
           new BaseInit(site, new ReviewDbDataSourceProvider(), false, false,
-              pluginsDistribution).run();
+              pluginsDistribution, pluginsToInstall).run();
         }
       } finally {
         conn.close();

gerrit-war/src/main/java/com/google/gerrit/httpd/WebAppInitializer.java

@@ -17,6 +17,7 @@ package com.google.gerrit.httpd;
 import static com.google.inject.Scopes.SINGLETON;
 import static com.google.inject.Stage.PRODUCTION;
 
+import com.google.common.base.Splitter;
 import com.google.gerrit.common.ChangeHookRunner;
 import com.google.gerrit.httpd.auth.openid.OpenIdModule;
 import com.google.gerrit.httpd.plugins.HttpPluginModule;
@@ -122,8 +123,16 @@ public class WebAppInitializer extends GuiceServletContextListener
       }
 
       if (System.getProperty("gerrit.init") != null) {
+        List<String> pluginsToInstall;
+        String installPlugins = System.getProperty("gerrit.install_plugins");
+        if (installPlugins == null) {
+          pluginsToInstall = null;
+        } else {
+          pluginsToInstall = Splitter.on(",").trimResults().omitEmptyStrings()
+              .splitToList(installPlugins);
+        }
         new SiteInitializer(path, System.getProperty("gerrit.init_path"),
-            new UnzippedDistribution(servletContext)).init();
+            new UnzippedDistribution(servletContext), pluginsToInstall).init();
       }
 
       try {