title: how do you emit to specific user in a specific room
body: <p>Hey guys please i need help emiting data to a specific user in a specific room using socket.io, am using redis to store the id's of the admin who created the group, but how do i get the userid from redis and emit to them in their room</p>
  <p><strong>my code</strong></p>
  <pre><code>const users = {} 
  const admins = {}
  
  
  io.on('connection',socket =&gt;{
  
  socket.on('create-class',(address,userID)=&gt;{
    client.hmset(`${userID}`, `id`, `${userID}`); 
  })
  
  
  socket.on('join-class',(classId,palsid)=&gt;{
    
        socket.join(classId)
        client.hgetall(`${palsid}`, function(err, object) {
          if(err)throw err
            
            if(object !==null){
              admins[socket.id] = object.id 
            }
           
             socket.to(classId).broadcast.emit('user-connected',palsid)
         
      });                    
       
        
  
        //on disconnection
        socket.on('disconnect',()=&gt;{
            socket.to(classId).broadcast.emit('user-disconnect',palsid)
        })
  
     
    })
  </code></pre>