public string GetDocument(string serverIP, string documentName)
{
// retrieve requested document from the specified server
// manage the session with the SD Server
// opening or resuming as needed
// connect to and disconnect from the server w/in this method
// make sure we have valid parameters
// serverIP is the SD Server's IP address
// documentName is the name of a docoument on the SD Server
// both should not be empty
if (String.IsNullOrWhiteSpace(serverIP) || String.IsNullOrWhiteSpace(documentName))
{
throw new Exception("EMpty server IP or document name!");
}
// contact the PRS and lookup port for "SD Server"
PRSClient prs = new PRSClient(prsIP, prsPort, "SD Server");
ushort sdPort = prs.LookupPort();
// connect to SD server by ipAddr and port
// use OpenOrResumeSession() to ensure session is handled correctly
SDClient client = OpenOrResumeSession(serverIP, sdPort);
// send get message to server for requested document
string content = client.GetDocument(documentName);
// disconnect from server
client.Disconnect();
// return the content
return(content);
}
private SDClient OpenOrResumeSession(string ipAddr, ushort port)
{
// create and connect an SDClient instance to the given SD Server
// open or resume a session
// leave the SDClient connected and return it for communication to the server
// Create SDClient and connect to the server
// connect to the SD Server's IP address and port
SDClient client = new SDClient(ipAddr, port);
client.Connect();
// do we already have a session for this server?
if (sessions.ContainsKey(ipAddr))
{
// yes, session already open
// retrieve the sessionId and send resume message to server
ulong sessionId = sessions[ipAddr].sessionId;
// Resume the session on the server
client.ResumeSession(sessionId);
}
else
{
// no, session not open for this server
// open a new session and save the sessionId
client.OpenSession();
// save this open session in the sessions dictionary for later
sessions[ipAddr] = new SDSession(ipAddr, port, client.SessionID);
}
// keep the client open and return it
return(client);
}
private void Form1_Closing(object sender, EventArgs e)//Form closing
{
if (SDSessions.Count > 0)
{
foreach (KeyValuePair <string, SDClient> pair in SDSessions)
{
string serverIP = pair.Key;
SDClient client = pair.Value;
try
{
client.CloseSession();
}
catch (Exception ex)
{
MessageBox.Show("Failed to close session to server:" + serverIP + ", error: " + ex.Message);
}
}
}
}
public void Close()
{
// close each open session with the various servers
// for each session...
foreach (SDSession session in sessions.Values)
{
// connect to the SD Server's IP address and port
SDClient client = new SDClient(session.ipAddr, session.port);
client.Connect();
// send the close for this sessionId
client.SessionID = session.sessionId;
client.CloseSession();
// disconnect from server
client.Disconnect();
}
sessions.Clear();
}
private void SDGet(string serverIP, string directoryName)
{
contentTextBox.Clear();//Clear the text box
try
{
SDClient client = null;
if (SDSessions.ContainsKey(serverIP)) //Session is already started
{
client = SDSessions[serverIP]; //Get the session from the session dict
}
else//if we dont have a session we need to make a new session
{
client = new SDClient(PRS_ADDRESS, PRS_PORT, serverIP);
SDSessions[serverIP] = client;
}
string documentcontents = client.Get(directoryName); //Get command on the SDClient
contentTextBox.AppendText(documentcontents); //Put the text in the textbox
}
catch (Exception e)
{
MessageBox.Show(e.ToString());//Display error message
}
}
