lnet TCP server - OnCanSend
lazarus / 38-Networking and Web Programming

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DelphiDinosaur · 2023-04-24 09:19

I have created a class that wraps the lnet TLTCPComponent to provide a
set of functions to simplify Tx/Rx to/from clients.

The "standard" Send function for my server works OK
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i procedure
TDemo.Send(const AValue array of byte)var  n: integer;begin 
MySocket.IterReset;  while MySocket.IterNext do  begin      n :=
MySocket.Send(AValue[0], Length(AValue), MySocket.Iterator); 
end;end;As expected this sends the byte arrays to each connected
client. So far so good.
The problem I have is when one (or more) of the clients can't accept
data at the rate I'm sending it (up to 200kByte per sec, generated in
2kByte chunks). I can't change the clients so need to cope with this
problem at the server end.

I'm aware that I need to more towards using the OnCanSend event but
I've been unable to find a decent example that works with the server
end of the connection.
I believe I can do some thing like the following:Code: Pascal
 [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i TxBuffer:
Array of byte;P: integer;procedure TDemo.Send(const AValue array of
byte);var  n: integer;begin  MySocket.IterReset;  while
MySocket.IterNext do  begin    SetLength(TxBuffer, Length(AValue));  
Move(AValue[0], TxBuffer[0], Length(AValue));    P := 0;    n :=
DoOnCanSend(MySocket.Iterator);  end;end;Where TxBuffer is usedCode:
Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i procedure
TDemo.DoOnCanSend(aSocket: TLSocket);var  n: integer;begin  repeat
 begin    if (Length(TxBuffer) > 0) and (P < Length(TxBuffer) then  
 begin      n := MySocket.Send(TxBuffer[P], Length(TxBuffer) - P,
aSocket);      inc(P, n);    end  end  until (n = 0) or (P >=
Length(TxBuffer));end;  Where I'm struggling is to manage the sending
the data to all the connected clients. Do I need to create an instance
of TxBuffer for each client?

Suggestions to good server examples welcome!

Dephi Dino.