Python Server/Client Application Development

Hey All!
I am writing a basic proof of concept server/client application for a project I am working on.
My goal is this:
1) End user launches client.
2) Client connects to server.
3) User selects one or more files to send to server.
4) Server saves a copy of each file.
5) Server terminates connection.
5) Server processes each file.
6) Upon completion of the processing server sets a "processing completed flag."
7) Client periodically checks with server for "processing completed flag."
8) Client securely reconnects
9) Client downloads processed files.
I have no background in programming servers/clients so this will be a learning experience for me and the workflow described above may change as I learn more about how this all works. Currently my hope is to first implement a system that will stay connected while the files are processed and once I have a better understanding as to how that works I can add more complexity to the system.
I will be writing this in Python 3.3 and the server will be hosted on a server which will (for now) be running Arch.
This thread will act as a sort of development journal but feel free to comment or post suggestions. I will for sure have questions as I go along too!

brettski wrote:Turns out the best way (so far as I can tell) is to go integer -> string -> byte and then byte -> string -> integer..
Do you mean regular, non-byte strings? That cannot possibly be the best way to do it. It would be like using Russian as an intermediary language for translating Spanish to French.
Maybe the following will set you on the right path:
http://stackoverflow.com/questions/6187 … -in-python
http://stackoverflow.com/questions/4445 … int-python
Looking further, this is probably the right way to do it:
some_int = 57
bytes = struct.pack('i', bytes)
sock.send(bytes)
See http://docs.python.org/3/library/struct.html for details.
As for threaded servers, you may find some useful examples here.

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Edited by: 844427 on Jan 12, 2012 12:15 AM
Edited by: 844427 on Jan 12, 2012 12:16 AM

Hi EJP,
Thanks for the suggestion ,
Here is sample code :
public class Lobby implements LobbyModelsChangeListener{
    Stage stage;
    ListView<String> listView;
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     public Lobby(Stage primaryStage) {
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java.lang.IllegalStateException: Not on FX application thread; currentThread = Thread-5
         at line         ol.addAll(ar);
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Vijay

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Purpose of Multiple Clients in Development Server

can anybody tell me the advantages and
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DEV SAP system may have multiple clients..
Main pupose : Changes can be client dependent or client independent
Client-independent effects some clients.
Client-dependent effects all clients.
Let me say one example : Dev system has two clients
100 - Here we can write the code
200 - Testing will be here ( customizing will done here)
http://help.sap.com/saphelp_nw04/helpdata/en/8d/933d3c3a926614e10000000a11402f/frameset.htm
http://www.sap-img.com/general/what-is-sap--landscape.htm
http://help.sap.com/saphelp_nw2004s/helpdata/en/96/8a99386185c064e10000009b38f8cf/content.htm
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