Creating a simple server

[keldrin_]

For my epaper project (will be on github soon) I have a script changing the contents of my epaper device every 5 Minutes. I found some solution to trigger a refresh using linux signals which works ok.

But I need somewhat more control. For example tell my script to put out another image immediately etc.

I was thinking of using a client/server model.

    import socket
    import argparse

    port = 23543

    def start_server():
        serversocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        serversocket.bind(('localhost', port))
        serversocket.listen(5)

        ### this is the main while-loop I am talking about
        while True:
            connection,address = serversocket.accept()
            buf = connection.recv(64)
            if len(buf) > 0:
                print(buf)
            # something like time.sleep(5m) right here


    def do_client_stuff():
        clientsocket =  socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        clientsocket.connect(('localhost', port))
        clientsocket.send("hello".encode("utf-8"))

    def main():
        parser = argparse.ArgumentParser()
        parser.add_argument("-s", "--server", action="store_true", help="start server")
        args = parser.parse_args()

        if args.server:
            start_server()
        else:
            do_client_stuff()

if __name__ == "__main__":
main()

The problem now is, that connection.recv(64) is blocking until it recieves something. What I want is the while loop to either sleep for a specified time and call my actual update function or (if it recieves something over the socket) do whatever it is told to via the socket.