Add REST tests for reset index settings and for listing defaults.

core/src/main/java/org/elasticsearch/rest/action/admin/indices/settings/RestGetSettingsAction.java

@@ -26,6 +26,7 @@ import org.elasticsearch.action.support.IndicesOptions;
 import org.elasticsearch.client.Client;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.inject.Inject;
+import org.elasticsearch.common.settings.IndexScopeSettings;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentBuilderString;
@@ -42,9 +43,12 @@ import static org.elasticsearch.rest.RestStatus.OK;
 
 public class RestGetSettingsAction extends BaseRestHandler {
 
+    private final IndexScopeSettings indexScopeSettings;
+
     @Inject
-    public RestGetSettingsAction(Settings settings, RestController controller, Client client) {
+    public RestGetSettingsAction(Settings settings, RestController controller, Client client, IndexScopeSettings indexScopeSettings) {
         super(settings, controller, client);
+        this.indexScopeSettings = indexScopeSettings;
         controller.registerHandler(GET, "/{index}/_settings/{name}", this);
         controller.registerHandler(GET, "/_settings/{name}", this);
         controller.registerHandler(GET, "/{index}/_setting/{name}", this);
@@ -53,6 +57,7 @@ public class RestGetSettingsAction extends BaseRestHandler {
     @Override
     public void handleRequest(final RestRequest request, final RestChannel channel, final Client client) {
         final String[] names = request.paramAsStringArrayOrEmptyIfAll("name");
+        final boolean renderDefaults = request.paramAsBoolean("defaults", false);
         GetSettingsRequest getSettingsRequest = new GetSettingsRequest()
                 .indices(Strings.splitStringByCommaToArray(request.param("index")))
                 .indicesOptions(IndicesOptions.fromRequest(request, IndicesOptions.strictExpandOpen()))
@@ -71,9 +76,14 @@ public class RestGetSettingsAction extends BaseRestHandler {
                         continue;
                     }
                     builder.startObject(cursor.key, XContentBuilder.FieldCaseConversion.NONE);
-                    builder.startObject(Fields.SETTINGS);
+                    builder.startObject("settings");
                     cursor.value.toXContent(builder, request);
                     builder.endObject();
+                    if (renderDefaults) {
+                        builder.startObject("defaults");
+                        indexScopeSettings.diff(cursor.value, settings).toXContent(builder, request);
+                        builder.endObject();
+                    }
                     builder.endObject();
                 }
                 builder.endObject();
@@ -81,8 +91,4 @@ public class RestGetSettingsAction extends BaseRestHandler {
             }
         });
     }
-
-    static class Fields {
-        static final XContentBuilderString SETTINGS = new XContentBuilderString("settings");
-    }
 }

rest-api-spec/src/main/resources/rest-api-spec/api/cluster.get_settings.json

@@ -18,6 +18,11 @@
         "timeout": {
           "type" : "time",
           "description" : "Explicit operation timeout"
+        },
+        "defaults": {
+          "type": "boolean",
+          "description": "Whether to return all default clusters setting.",
+          "default": false
         }
       }
     },

rest-api-spec/src/main/resources/rest-api-spec/api/indices.get_settings.json

@@ -42,6 +42,11 @@
           "type": "boolean",
           "description": "Whether to return version and creation date values in human-readable format.",
           "default": false
+        },
+        "defaults": {
+          "type": "boolean",
+          "description": "Whether to return all default setting for each of the indices.",
+          "default": false
         }
       }
     },

rest-api-spec/src/main/resources/rest-api-spec/test/indices.put_settings/11_reset.yaml

@@ -0,0 +1,39 @@
+setup:
+  - do:
+      indices.create:
+        index: test-index
+        body:
+          settings:
+            index:
+              refresh_interval: "10s"
+
+---
+"Test reset index settings":
+  - do:
+      indices.get_settings:
+        index: test-index
+        flat_settings: true
+
+  - match:
+      test-index.settings.index.refresh_interval: "10s"
+
+  - do:
+      indices.put_settings:
+        body:
+          refresh_interval: null
+
+  - do:
+      indices.get_settings:
+        flat_settings: false
+
+  - match:
+      - match: {index.settings: {}}
+
+  - do:
+      indices.get_settings:
+        flat_settings: true
+        defaults: true
+
+  - match:
+        test-index.settings.index.refresh_interval: "1s"
+