To check if SP user group is already present in current Site using JSOM

Question

How to check if a user group with a particular is already present in sharepoint using javascript or JSOM? and if not present then create one.. I am new to sharepoint and got info everywhere with C# code

Answer 1

Below is the complete code which meets your requirement.

1. Check if particular SP group Exist
2. If not, Create one

   <script language="javascript" type="text/javascript">
    function clickMe() {          
    var clientContext = new SP.ClientContext.get_current(); 
    siteGroups = clientContext.get_web().get_siteGroups();
    clientContext.load(siteGroups);
    clientContext.executeQueryAsync(onQuerySucceeded, onQueryFailed);
    }        
    function onQuerySucceeded() {
    var ifGroupExist = false;
    for (var i =0 ; i < siteGroups.get_count(); i++)
        {
           if("my_particular_group_name" == siteGroups.itemAt(i).get_title()){
                ifGroupExist = true;                    
           }
        }
    // create SP group if it does not exist
    if(!ifGroupExist) { createSPGroup();}
   }
    function onQueryFailed() {    
        alert('Request failed');
    }    

    function createSPGroup()
    {
        var web = context.get_web();      
        var groupCollection = web.get_siteGroups();  
        // Create Group information for Group  
        var newGRP = new SP.GroupCreationInformation();  
        newGRP.set_title("your_particular_Group");  
        newGRP.set_description("sample description");  

        var currentUser = web.get_currentUser();  
        context.load(currentUser);  

        context.load(web, 'Title', 'HasUniqueRoleAssignments');  
        context.executeQueryAsync(function() {  

        if (!web.get_hasUniqueRoleAssignments()) {  
            web.breakRoleInheritance(true, false);  
        }  

        //add group to site gorup collection  
        var newCreateGroup = groupCollection.add(newGRP);  
        //Role Definition   
        var rolDef = web.get_roleDefinitions().getByName("Edit");  
        var rolDefColl = SP.RoleDefinitionBindingCollection.newObject(context);  
        rolDefColl.add(rolDef);  

        // Get the RoleAssignmentCollection for the target web.  
        var roleAssignments = web.get_roleAssignments();  
        // assign the group to the new RoleDefinitionBindingCollection.  
        roleAssignments.add(newCreateGroup, rolDefColl);  
        //Set group properties  
        newCreateGroup.set_allowMembersEditMembership(true);  
        newCreateGroup.set_onlyAllowMembersViewMembership(false);  
        newCreateGroup.update();  
        context.load(newCreateGroup);            
        context.executeQueryAsync(success, fail);       
    }
   function success() {  
             alert("Successfully created group: your_particular_Group");  
   }        
    function fail() {  
        alert("Failed to create group");  
    }
        </script>