Recv Over Sockets in Python

I finally figured it out. How do you get an arbitrary length of data no matter what in python over sockets?

The problem is this. Suppose you have a connected socket between two machines A and B.

Suppose A does socketA.sendall(<some long string>). Now how does B recv all the data.

If B does socketB.recv(1024) its going to possibly get the first packet that was sent. B does not know how long it has to wait or how much data there is. The simplest solution is for A to attach the length of the data as in socketA.sendall(str(len(<data>)) + <data>)

A better way, ladies and gentlemen (Yes, this seemingly obvious bit of code finally struck after 4 years of programming in python) and it is applicable across any language

def getDataFromSocket(sck):
    data = “”
    sck.settimeout(None)
    data = sck.recv(1024)
    sck.settimeout(2)

    while 1:
        line = “”
        try:
            line = sck.recv(1024)
        except socket.timeout:
            break

        if line == “”:
            break

        data += line
    return data

 

Yes. You may all thank me now.