AfterEffects Python Communication

acp.py

import os
import socket
import traceback


def send(cmd, port):

    host = '127.0.0.1'

    # we expect a result no matter if it errors, so we keep trying until we
    # get a reply. This is slow, but relyable.
    keep_trying = True
    result = ""
    while(keep_trying):
        conn = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        conn.connect((host, port))
        conn.send(cmd)
        try:
            result = conn.recv(4096)
            conn.close()
            if result:
                keep_trying = False
        except:
            pass

    # raise error
    if result.startswith("Error: "):
        msg = result.replace("Error: ", "")
        msg += "CMD: " + cmd
        raise ValueError(msg)

    # all replies comes in with a newline
    result = result.replace("\n", "")

    # more Pythonic return of nothing
    if result == "undefined":
        return None

    return result


def stop_server(port):
    send("keep_serving = false", port)


if __name__ == '__main__':
    port = int(os.environ["AFTEREFFECTS_PORT"])
    try:
        # Experiment with sending Javascipt commands here safely.
        print "After Effect version: {0}".format(
            send("return app.version", port)
        )
    except:
        print traceback.format_exc()
    finally:
        raw_input("Pause... Press any key to continue")
        stop_server(port)

apc.jsx

// settting port environment variable
var port = Math.floor((Math.random() * 1000) + 8000);
$.setenv("AFTEREFFECTS_PORT", port);

// start pyblish lite
var filename = ""
try{
    filename = app.project.file.fsName
}catch(err){}

// Remember forward slashes for the python script path
var cmd = "start \"\" python \"/path/to/acp.py\""
var batFile= new File("~/aftereffects.bat");
batFile.open("w");
batFile.write(cmd);
batFile.close();
batFile.execute();

// create a new socket
conn = new Socket();

var keep_serving = true;

while (keep_serving) {
    if (conn.listen(port))  // ... you'd probably want to make this configurable
    {
        // wait forever for a connection
        var incoming;
        do incoming = conn.poll();
        while (incoming == null);

        // grab the next non-null communication
        new_cmd = incoming.read();
        try {
            var F = new Function (new_cmd);
            var results = F();
            incoming.writeln(results);
        }
        catch (err) {
            incoming.writeln("Error: " + err.toString());
        }
    } // end if
} // -- end while