Index: lams_central/conf/security/Owasp.CsrfGuard.properties
===================================================================
diff -u -rf86004309489cb81f283d1962b481b4bbb3facd6 -r8d372a4476d25a498b5af8c04e82576edc7b0976
--- lams_central/conf/security/Owasp.CsrfGuard.properties	(.../Owasp.CsrfGuard.properties)	(revision f86004309489cb81f283d1962b481b4bbb3facd6)
+++ lams_central/conf/security/Owasp.CsrfGuard.properties	(.../Owasp.CsrfGuard.properties)	(revision 8d372a4476d25a498b5af8c04e82576edc7b0976)
@@ -142,6 +142,7 @@
 org.owasp.csrfguard.protected.dokuAuthoringSave=/lams/tool/ladoku11/authoring/update.do
 org.owasp.csrfguard.protected.dokuAuthoringDefineLater=/lams/tool/ladoku11/authoring/definelater.do
 org.owasp.csrfguard.protected.dokuMonitoringUpdateLearnerMark=/lams/tool/ladoku11/monitoring/updateLearnerMark.do
+org.owasp.csrfguard.protected.dokuMonitoringChangeLeader=/lams/tool/ladoku11/monitoring/changeLeaderForGroup.do
 
 org.owasp.csrfguard.protected.forumAuthoringSave=/lams/tool/lafrum11/authoring/update.do
 org.owasp.csrfguard.protected.forumAuthoringDefineLater=/lams/tool/lafrum11/authoring/definelater.do
Index: lams_tool_doku/conf/language/lams/ApplicationResources.properties
===================================================================
diff -u -r29997e1d587d3ced8db5f525058eafb4e9742b2d -r8d372a4476d25a498b5af8c04e82576edc7b0976
--- lams_tool_doku/conf/language/lams/ApplicationResources.properties	(.../ApplicationResources.properties)	(revision 29997e1d587d3ced8db5f525058eafb4e9742b2d)
+++ lams_tool_doku/conf/language/lams/ApplicationResources.properties	(.../ApplicationResources.properties)	(revision 8d372a4476d25a498b5af8c04e82576edc7b0976)
@@ -85,6 +85,9 @@
 label.monitoring.learner.marks.last.name = Last name
 label.monitoring.learner.marks.mark = Mark
 label.monitoring.learner.marks.mark.tip = (click to edit; max: 100)
+label.monitoring.change.leader = Change leader
+label.monitoring.leader.successfully.changed = Leader changed
+label.monitoring.leader.not.changed = Leader was not changed
 messsage.monitoring.learner.marks.no.data = No learner data found
 messsage.monitoring.learner.marks.update.fail = Error while updating a learner mark
 outcome.authoring.title = Learning outcomes
Index: lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/dokumaranApplicationContext.xml
===================================================================
diff -u -r2509a4b8ae30079b238c0af1c508466517584e3b -r8d372a4476d25a498b5af8c04e82576edc7b0976
--- lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/dokumaranApplicationContext.xml	(.../dokumaranApplicationContext.xml)	(revision 2509a4b8ae30079b238c0af1c508466517584e3b)
+++ lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/dokumaranApplicationContext.xml	(.../dokumaranApplicationContext.xml)	(revision 8d372a4476d25a498b5af8c04e82576edc7b0976)
@@ -95,6 +95,7 @@
             <props>
                 <prop key="addOneMinute">PROPAGATION_REQUIRED,-java.lang.Exception</prop> 
             	<prop key="audit*">PROPAGATION_REQUIRED</prop>    
+            	<prop key="change*">PROPAGATION_REQUIRED,-java.lang.Exception</prop>
             	<prop key="check*">PROPAGATION_REQUIRED,-java.lang.Exception</prop>
                 <prop key="copyToolContent">PROPAGATION_REQUIRED,-java.lang.Exception</prop> 
                 <prop key="create*">PROPAGATION_REQUIRED,-java.lang.Exception</prop>
Index: lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/dto/SessionDTO.java
===================================================================
diff -u -r368e60d0fd7df1a3e327670ef9d0f3487803110b -r8d372a4476d25a498b5af8c04e82576edc7b0976
--- lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/dto/SessionDTO.java	(.../SessionDTO.java)	(revision 368e60d0fd7df1a3e327670ef9d0f3487803110b)
+++ lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/dto/SessionDTO.java	(.../SessionDTO.java)	(revision 8d372a4476d25a498b5af8c04e82576edc7b0976)
@@ -32,6 +32,8 @@
     private String readOnlyPadId;
     private boolean sessionFaulty;
     private ItemRatingDTO itemRatingDto;
+    private int numberOfLearners;
+    private boolean sessionFinished;
 
     public Long getSessionId() {
 	return sessionId;
@@ -80,4 +82,20 @@
     public void setItemRatingDto(ItemRatingDTO ratingDto) {
 	this.itemRatingDto = ratingDto;
     }
+
+    public int getNumberOfLearners() {
+        return numberOfLearners;
+    }
+
+    public void setNumberOfLearners(int numberOfLearners) {
+        this.numberOfLearners = numberOfLearners;
+    }
+
+    public boolean isSessionFinished() {
+        return sessionFinished;
+    }
+
+    public void setSessionFinished(boolean sesssionFinished) {
+        this.sessionFinished = sesssionFinished;
+    }
 }
\ No newline at end of file
Index: lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/service/DokumaranService.java
===================================================================
diff -u -r7eab6b4371036949ed61a387bc7706473895f567 -r8d372a4476d25a498b5af8c04e82576edc7b0976
--- lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/service/DokumaranService.java	(.../DokumaranService.java)	(revision 7eab6b4371036949ed61a387bc7706473895f567)
+++ lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/service/DokumaranService.java	(.../DokumaranService.java)	(revision 8d372a4476d25a498b5af8c04e82576edc7b0976)
@@ -24,6 +24,7 @@
 package org.lamsfoundation.lams.tool.dokumaran.service;
 
 import java.io.IOException;
+import java.security.InvalidParameterException;
 import java.util.ArrayList;
 import java.util.Date;
 import java.util.LinkedList;
@@ -267,6 +268,39 @@
     }
 
     @Override
+    public void changeLeaderForGroup(long toolSessionId, long leaderUserId) {
+	DokumaranSession session = getDokumaranSessionBySessionId(toolSessionId);
+	if (DokumaranConstants.COMPLETED == session.getStatus()) {
+	    throw new InvalidParameterException("Attempting to assing a new leader with user ID " + leaderUserId
+		    + " to a finished session wtih ID " + toolSessionId);
+	}
+
+	DokumaranUser existingLeader = session.getGroupLeader();
+	if (existingLeader == null || existingLeader.getUserId().equals(leaderUserId)) {
+	    return;
+	}
+	Dokumaran dokumaran = session.getDokumaran();
+	DokumaranUser newLeader = getUserByIDAndContent(leaderUserId, dokumaran.getContentId());
+	if (newLeader == null) {
+	    return;
+	}
+	if (!newLeader.getSession().getSessionId().equals(toolSessionId)) {
+	    throw new InvalidParameterException("User with ID " + leaderUserId + " belongs to session with ID "
+		    + newLeader.getSession().getSessionId() + " and not to session with ID " + toolSessionId);
+	}
+
+	session.setGroupLeader(newLeader);
+	dokumaranSessionDao.update(session);
+
+	Set<Integer> userIds = getUsersBySession(toolSessionId).stream()
+		.collect(Collectors.mapping(dokumaranUser -> dokumaranUser.getUserId().intValue(), Collectors.toSet()));
+
+	ObjectNode jsonCommand = JsonNodeFactory.instance.objectNode();
+	jsonCommand.put("hookTrigger", "doku-leader-change-refresh-" + toolSessionId);
+	learnerService.createCommandForLearners(dokumaran.getContentId(), userIds, jsonCommand.toString());
+    }
+
+    @Override
     public void launchTimeLimit(Long toolContentId) throws IOException {
 	Dokumaran dokumaran = getDokumaranByContentId(toolContentId);
 	dokumaran.setTimeLimitLaunchedDate(new Date());
@@ -447,6 +481,8 @@
 	    SessionDTO group = new SessionDTO();
 	    group.setSessionId(session.getSessionId());
 	    group.setSessionName(session.getSessionName());
+	    group.setNumberOfLearners(getUsersBySession(session.getSessionId()).size());
+	    group.setSessionFinished(DokumaranConstants.COMPLETED == session.getStatus());
 	    group.setPadId(session.getPadId());
 	    group.setReadOnlyPadId(session.getEtherpadReadOnlyId());
 
Index: lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/service/IDokumaranService.java
===================================================================
diff -u -re0cdeed1959c06ed434e7a4abec0aa5722128c8b -r8d372a4476d25a498b5af8c04e82576edc7b0976
--- lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/service/IDokumaranService.java	(.../IDokumaranService.java)	(revision e0cdeed1959c06ed434e7a4abec0aa5722128c8b)
+++ lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/service/IDokumaranService.java	(.../IDokumaranService.java)	(revision 8d372a4476d25a498b5af8c04e82576edc7b0976)
@@ -239,4 +239,6 @@
     void startGalleryWalk(long toolContentId) throws IOException;
 
     void finishGalleryWalk(long toolContentId) throws IOException;
+
+    void changeLeaderForGroup(long toolSessionId, long leaderUserId);
 }
\ No newline at end of file
Index: lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/web/controller/MonitoringController.java
===================================================================
diff -u -r368e60d0fd7df1a3e327670ef9d0f3487803110b -r8d372a4476d25a498b5af8c04e82576edc7b0976
--- lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/web/controller/MonitoringController.java	(.../MonitoringController.java)	(revision 368e60d0fd7df1a3e327670ef9d0f3487803110b)
+++ lams_tool_doku/src/java/org/lamsfoundation/lams/tool/dokumaran/web/controller/MonitoringController.java	(.../MonitoringController.java)	(revision 8d372a4476d25a498b5af8c04e82576edc7b0976)
@@ -61,11 +61,13 @@
 import org.lamsfoundation.lams.web.util.SessionMap;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.http.HttpStatus;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.ResponseBody;
+import org.springframework.web.bind.annotation.ResponseStatus;
 
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.fasterxml.jackson.databind.node.JsonNodeFactory;
@@ -276,6 +278,14 @@
 
     }
 
+    @RequestMapping(path = "/changeLeaderForGroup", method = RequestMethod.POST)
+    @ResponseBody
+    @ResponseStatus(HttpStatus.OK)
+    public void changeLeaderForGroup(@RequestParam(name = AttributeNames.PARAM_TOOL_SESSION_ID) long toolSessionId,
+	    @RequestParam long leaderUserId) {
+	dokumaranService.changeLeaderForGroup(toolSessionId, leaderUserId);
+    }
+
     @RequestMapping("/startGalleryWalk")
     private void startGalleryWalk(HttpServletRequest request) throws IOException {
 	Long toolContentId = WebUtil.readLongParam(request, DokumaranConstants.ATTR_TOOL_CONTENT_ID, false);
Index: lams_tool_doku/web/pages/learning/learning.jsp
===================================================================
diff -u -r53041ab71ac581668c14bdf40f65be5ea5f26961 -r8d372a4476d25a498b5af8c04e82576edc7b0976
--- lams_tool_doku/web/pages/learning/learning.jsp	(.../learning.jsp)	(revision 53041ab71ac581668c14bdf40f65be5ea5f26961)
+++ lams_tool_doku/web/pages/learning/learning.jsp	(.../learning.jsp)	(revision 8d372a4476d25a498b5af8c04e82576edc7b0976)
@@ -74,6 +74,17 @@
 			}
 			
 			$('[data-toggle="tooltip"]').bootstrapTooltip();
+
+			<%-- Connect to command websocket only if it is learner UI --%>
+			<c:if test="${dokumaran.useSelectLeaderToolOuput and mode == 'learner'}">
+				// command websocket stuff for refreshing
+				// trigger is an unique ID of page and action that command websocket code in Page.tag recognises
+				commandWebsocketHookTrigger = 'doku-leader-change-refresh-${toolSessionID}';
+				// if the trigger is recognised, the following action occurs
+				commandWebsocketHook = function() {
+					location.reload();
+				};
+			</c:if>
 		});
 		
 		if (${!hasEditRight && mode != "teacher" && !finishedLock}) {
Index: lams_tool_doku/web/pages/monitoring/summary.jsp
===================================================================
diff -u -r8e8e7b3f0982e5e772b90202f01d43f1ee52962d -r8d372a4476d25a498b5af8c04e82576edc7b0976
--- lams_tool_doku/web/pages/monitoring/summary.jsp	(.../summary.jsp)	(revision 8e8e7b3f0982e5e772b90202f01d43f1ee52962d)
+++ lams_tool_doku/web/pages/monitoring/summary.jsp	(.../summary.jsp)	(revision 8d372a4476d25a498b5af8c04e82576edc7b0976)
@@ -412,6 +412,38 @@
 			}
 		});
 	}
+
+
+	function showChangeLeaderModal(toolSessionId) {
+		$('#change-leader-modals').empty()
+		.load('<lams:LAMSURL/>tool/lalead11/monitoring/displayChangeLeaderForGroupDialogFromActivity.do',{
+			toolSessionId : toolSessionId
+		});
+	}
+
+	function onChangeLeaderCallback(response, leaderUserId, toolSessionId){
+        if (response.isSuccessful) {
+            $.ajax({
+    			'url' : '<c:url value="/monitoring/changeLeaderForGroup.do"/>',
+    			'type': 'post',
+    			'cache' : 'false',
+    			'data': {
+    				'toolSessionID' : toolSessionId,
+    				'leaderUserId' : leaderUserId,
+    				'<csrf:tokenname/>' : '<csrf:tokenvalue/>'
+    			},
+    			success : function(){
+    				alert("<fmt:message key='label.monitoring.leader.successfully.changed'/>");
+    			},
+    			error : function(){
+    				alert("<fmt:message key='label.monitoring.leader.not.changed'/>");
+        		}
+            });
+        	
+		} else {
+			alert("<fmt:message key='label.monitoring.leader.not.changed'/>");
+		}
+	}
 </script>
 <script type="text/javascript" src="${lams}includes/javascript/rating.js"></script>
 <script type="text/javascript" src="${lams}includes/javascript/jquery.jRating.js"></script>
@@ -510,6 +542,12 @@
 					<fmt:message key="monitoring.label.group" />&nbsp;${groupSummary.sessionName}
 				</a>
 			</span>
+			<c:if test="${dokumaran.useSelectLeaderToolOuput and groupSummary.numberOfLearners > 0 and not groupSummary.sessionFinished}">
+				<button type="button" class="btn btn-default btn-xs pull-right"
+						onClick="javascript:showChangeLeaderModal(${groupSummary.sessionId})">
+					<fmt:message key='label.monitoring.change.leader'/>
+				</button>
+			</c:if>
         </div>
         
         <div id="collapse${groupSummary.sessionId}" class="panel-collapse collapse etherpad-collapse" 
@@ -580,3 +618,5 @@
 </c:if>
 
 <%@ include file="advanceoptions.jsp"%>
+
+<div id="change-leader-modals"></div>
\ No newline at end of file