Python selector

import selectors

import  socket

 

sel  =  selectors.DefaultSelector()

 

def  accept(sock, mask):

     conn, addr  =  sock.accept()   # Should be ready

     print ( 'accepted' , conn,  'from' , addr)

     conn.setblocking( False )

     sel.register(conn, selectors.EVENT_READ, read)

 

def  read(conn, mask):

     data  =  conn.recv( 1000 )   # Should be ready

     if  data:

         print ( 'echoing' ,  repr (data),  'to' , conn)

         conn.send(data)   # Hope it won't block

     else :

         print ( 'closing' , conn)

         sel.unregister(conn)

         conn.close()

 

sock  =  socket.socket()

sock.bind(( 'localhost' ,  10000 ))

sock.listen( 100 )

sock.setblocking( False )

sel.register(sock, selectors.EVENT_READ, accept)

 

while  True :

     events  =  sel.select()

     for  key, mask  in  events:

         callback  =  key.data

         callback(key.fileobj, mask)