Settings: Remove environment from transport client

Transport clients run embedded within external applications, so
elasticsearch should not be doing anything with the filesystem, as there
is not elasticsearch home.

This change makes a number of cleanups to the internal API for loading
settings and creating an environment. The loadFromConfig option was
removed, since it was always true except for tests. We now always
attempt to load settings from config a file when an environment is
created. The prepare methods were also simplified so there is now
prepareSettingsAndEnvironment which nodes use, and prepareSettings which
the transport client uses. I also attempted to improve the tests, but
there is a still a lot of follow up work to do there.

closes elastic#13155

core/src/main/java/org/elasticsearch/bootstrap/Bootstrap.java

@@ -197,7 +197,7 @@ private static void setupLogging(Settings settings, Environment environment) {
 
     private static Tuple<Settings, Environment> initialSettings(boolean foreground) {
         Terminal terminal = foreground ? Terminal.DEFAULT : null;
-        return InternalSettingsPreparer.prepareSettings(EMPTY_SETTINGS, true, terminal);
+        return InternalSettingsPreparer.prepareSettingsAndEnvironment(EMPTY_SETTINGS, terminal);
     }
 
     private void start() {

core/src/main/java/org/elasticsearch/client/transport/TransportClient.java

@@ -85,7 +85,6 @@ public static class Builder {
 
         private Settings settings = Settings.EMPTY;
         private List<Class<? extends Plugin>> pluginClasses = new ArrayList<>();
-        private boolean loadConfigSettings = true;
 
         /**
          * The settings to configure the transport client with.
@@ -102,15 +101,6 @@ public Builder settings(Settings settings) {
             return this;
         }
 
-        /**
-         * Should the transport client load file based configuration automatically or not (and rely
-         * only on the provided settings), defaults to true.
-         */
-        public Builder loadConfigSettings(boolean loadConfigSettings) {
-            this.loadConfigSettings = loadConfigSettings;
-            return this;
-        }
-
         /**
          * Add the given plugin to the client when it is created.
          */
@@ -123,17 +113,16 @@ public Builder addPlugin(Class<? extends Plugin> pluginClass) {
          * Builds a new instance of the transport client.
          */
         public TransportClient build() {
-            Tuple<Settings, Environment> tuple = InternalSettingsPreparer.prepareSettings(settings, loadConfigSettings);
-            Settings settings = settingsBuilder()
+            Settings settings = InternalSettingsPreparer.prepareSettings(this.settings);
+            settings = settingsBuilder()
                     .put(NettyTransport.PING_SCHEDULE, "5s") // enable by default the transport schedule ping interval
-                    .put(tuple.v1())
+                    .put(settings)
                     .put("network.server", false)
                     .put("node.client", true)
                     .put(CLIENT_TYPE_SETTING, CLIENT_TYPE)
                     .build();
-            Environment environment = tuple.v2();
 
-            PluginsService pluginsService = new PluginsService(settings, tuple.v2(), pluginClasses);
+            PluginsService pluginsService = new PluginsService(settings, null, pluginClasses);
             this.settings = pluginsService.updatedSettings();
 
             Version version = Version.CURRENT;
@@ -149,7 +138,6 @@ public TransportClient build() {
                     modules.add(pluginModule);
                 }
                 modules.add(new PluginsModule(pluginsService));
-                modules.add(new EnvironmentModule(environment));
                 modules.add(new SettingsModule(this.settings));
                 modules.add(new NetworkModule());
                 modules.add(new ClusterNameModule(this.settings));

core/src/main/java/org/elasticsearch/common/cli/CliTool.java

@@ -104,7 +104,7 @@ protected CliTool(CliToolConfig config, Terminal terminal) {
         Preconditions.checkArgument(config.cmds().size() != 0, "At least one command must be configured");
         this.config = config;
         this.terminal = terminal;
-        Tuple<Settings, Environment> tuple = InternalSettingsPreparer.prepareSettings(EMPTY_SETTINGS, true, terminal);
+        Tuple<Settings, Environment> tuple = InternalSettingsPreparer.prepareSettingsAndEnvironment(EMPTY_SETTINGS, terminal);
         settings = tuple.v1();
         env = tuple.v2();
     }

core/src/main/java/org/elasticsearch/node/Node.java

@@ -133,7 +133,7 @@ public Node(Settings preparedSettings, boolean loadConfigSettings) {
     Node(Settings preparedSettings, boolean loadConfigSettings, Version version, Collection<Class<? extends Plugin>> classpathPlugins) {
         final Settings pSettings = settingsBuilder().put(preparedSettings)
                 .put(Client.CLIENT_TYPE_SETTING, CLIENT_TYPE).build();
-        Tuple<Settings, Environment> tuple = InternalSettingsPreparer.prepareSettings(pSettings, loadConfigSettings);
+        Tuple<Settings, Environment> tuple = InternalSettingsPreparer.prepareSettingsAndEnvironment(pSettings, null);
         tuple = new Tuple<>(TribeService.processSettings(tuple.v1()), tuple.v2());
 
         ESLogger logger = Loggers.getLogger(Node.class, tuple.v1().get("name"));
@@ -147,7 +147,7 @@ public Node(Settings preparedSettings, boolean loadConfigSettings) {
                     env.configFile(), Arrays.toString(env.dataFiles()), env.logsFile(), env.pluginsFile());
         }
 
-        this.pluginsService = new PluginsService(tuple.v1(), tuple.v2(), classpathPlugins);
+        this.pluginsService = new PluginsService(tuple.v1(), tuple.v2().pluginsFile(), classpathPlugins);
         this.settings = pluginsService.updatedSettings();
         // create the environment based on the finalized (processed) view of the settings
         this.environment = new Environment(this.settings());