Add setting to configure the default context size

The new setting `context:defaultSize` allows for customization of the
initial number of rows displayed when viewing an entry's context.

docs/management/advanced-options.asciidoc

@@ -74,3 +74,4 @@ Markdown.
 `notifications:lifetime:error`:: Specifies the duration in milliseconds for error notification displays. The default value is 300000. Set this field to `Infinity` to disable error notifications.
 `notifications:lifetime:warning`:: Specifies the duration in milliseconds for warning notification displays. The default value is 10000. Set this field to `Infinity` to disable warning notifications.
 `notifications:lifetime:info`:: Specifies the duration in milliseconds for information notification displays. The default value is 5000. Set this field to `Infinity` to disable information notifications.
+`context:defaultSize`:: Specifies the initial number of surrounding entries to display in the context view. The default value is 5.

src/core_plugins/kibana/public/context/index.js

@@ -24,8 +24,8 @@ uiRoutes
 });
 
 
-function ContextAppRouteController($routeParams, $scope, AppState, indexPattern) {
-  this.state = new AppState(createDefaultAppState());
+function ContextAppRouteController($routeParams, $scope, AppState, config, indexPattern) {
+  this.state = new AppState(createDefaultAppState(config));
   $scope.$watchGroup([
     'contextAppRoute.state.columns',
     'contextAppRoute.state.size',
@@ -34,9 +34,9 @@ function ContextAppRouteController($routeParams, $scope, AppState, indexPattern)
   this.indexPattern = indexPattern;
 }
 
-function createDefaultAppState() {
+function createDefaultAppState(config) {
   return {
     columns: ['_source'],
-    size: 5,
+    size: parseInt(config.get('context:defaultSize'), 10),
   };
 }

src/ui/settings/defaults.js

@@ -301,6 +301,10 @@ export default function defaultSettingsProvider() {
       description: 'The URL can sometimes grow to be too large for some browsers to ' +
         'handle. To counter-act this we are testing if storing parts of the URL in ' +
         'sessions storage could help. Please let us know how it goes!'
-    }
+    },
+    'context:defaultSize': {
+      value: 5,
+      description: 'The number of surrounding entries to show in the context view',
+    },
   };
 };