Functions to get info about Google Groups from the G Suite API in a Google spreadsheet

g_suite_groups.gs

function showMyGroups() {
  var current_sheet;
  var groups;
        
  current_sheet = SpreadsheetApp.getActiveSpreadsheet().getActiveSheet();
  groups = GroupsApp.getGroups();
  
  if (groups.length > 0) {
    current_sheet.clearContents();
    current_sheet.getRange(1, 1).setValue("You are a member of " + groups.length + " groups:");
    current_sheet.setColumnWidth(1, 240)
  
    for (var i = 0; i < groups.length; i++) {
      current_sheet.getRange(i+1, 2).setValue(groups[i].getEmail());
    }
  }
}

function listMembersOfGroup() {
  var current_sheet;
  var groupEmail;
  var members;
        
  current_sheet = SpreadsheetApp.getActiveSpreadsheet().getActiveSheet();
  
  groupEmail = Browser.inputBox("Mailinglist", "Which group do you want to know the members of?", Browser.Buttons.OK_CANCEL);
    
  try {
    members = GroupsApp.getGroupByEmail(groupEmail).getUsers();
    
    current_sheet.clearContents();
    current_sheet.getRange(1, 1).setValue("Members of " + groupEmail + ":");
    current_sheet.setColumnWidth(1, 240)
  
    for (var i = 0; i < members.length; i++) {
      current_sheet.getRange(i+1, 2).setValue(members[i].getEmail());
    }
  }
  
  catch(exception) {
    Browser.msgBox("Error", exception, Browser.Buttons.OK);
  }
}