settings: new option to disable event fetch from server side

admin/static/views/settings.html

@@ -150,6 +150,13 @@
       </label>
     </div>
 
+    <div class="form-check">
+      <label class="custom-control custom-checkbox">
+	<input class="custom-control-input" type="checkbox" ng-model="config.eventKindness">
+	<span class="custom-control-label">Réduire la relève d'évènements côté navigateur</span>
+      </label>
+    </div>
+
   </fieldset>
 </div>
 </form>

frontend/static/js/challenge.js

@@ -162,8 +162,16 @@ angular.module("FICApp", ["ngRoute", "ngSanitize"])
 		response.data.end = new Date(response.data.end);
 		response.data.generation = new Date(response.data.generation);
 		response.data.activateTime = new Date(response.data.activateTime);
-		if (response.data.activateTime <= new Date(Date.now() + (time.cu - time.he)))
+		if (response.data.activateTime <= new Date(Date.now() + (time.cu - time.he))) {
 		    $rootScope.settings = response.data;
+		    if (response.data.eventKindness && refreshEventsInterval) {
+			$interval.cancel(refreshEventsInterval);
+			refreshEventsInterval = null;
+		    }
+		    else if (!response.data.eventKindness && !refreshEventsInterval) {
+			refreshEvents();
+		    }
+		}
 		else
 		    $rootScope.settings.activateTime = response.data.activateTime;
 	    });

settings/settings.go

@@ -61,6 +61,8 @@ type FICSettings struct {
 	UnlockedChallengeDepth	int       `json:"unlockedChallengeDepth"`
 	// SubmissionUniqueness don't count multiple times identical tries.
 	SubmissionUniqueness    bool      `json:"submissionUniqueness"`
+	// EventKindness will ask browsers to delay notification interval.
+	EventKindness           bool      `json:"eventKindness"`
 }
 
 // ExistsSettings checks if the settings file can by found at the given path.