Synapse TCP Client issue ? maybe some help
lazarus / 38-Networking and Web Programming

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fpc2pas · 2021-05-24 16:27

Hi guys, recently i have a look into this amazing source code
https://forum.lazarus.freepascal.org/index.php?topic=48677.0, actually
is amazing and well written. currently, I am working to do that client
as a console application rather than GUI. but there is some issues I
am facing while not receiving anything sent from the server. but I
successfully managed to send into server below is sample of code I am
using

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 type   {
TMyApplication }   TMyApplication = class(TCustomApplication) // cbIP:
TComboBox;  protected    procedure DoRun; override;     private   
FTCPClient: TTCPClient;    FSettings: TSettings;    FTCPBase:
TTCPBase;    FTCPBaseType: TBaseType;    Connection: TConnection;   
procedure AddLog(ALogMsg: String);    procedure
DoOnRecvMessage(Sender: TObject; AMsg: String; AParams: TStringArray;
AConnection: TConnection);    procedure DoOnConnect(Sender: TObject;
AConnection: TConnection);   public  procedure execute;    constructor
Create(ATCPClient: TTCPClient);    destructor Destroy; override;   
procedure WriteHelp; virtual;    procedure connect_tcp; virtual;   
procedure sending(ATCPBase: TTCPBase; ATCPBaseType: TBaseType;
ASettings: TSettings; AConnection: TConnection);   // public  //
 procedure RecvMessage(Sender: TObject;AMsg: String; AParams:
TStringArray; {%H-}AConnection: TConnection; AddLog: TAddLog);  end; {
TMyApplication } type   TAddLog = procedure(ALogMsg: String) of
Object;    Tfrclient = class   private   FTCPBase: TTCPBase;   
FTCPBaseType: TBaseType;    FSettings: TSettings;    FConnection:
TConnection;  public     procedure RecvMessage(Sender: TObject; AMsg:
String; AParams: TStringArray; {%H-}AConnection: TConnection;
{%H-}AddLog: TAddLog);  end; procedure TMyApplication.DoRun;var 
ErrorMsg: String;begin  // quick check parameters 
ErrorMsg:=CheckOptions('h', 'help');  if ErrorMsg<>'' then begin   
ShowException(Exception.Create(ErrorMsg));    Terminate;    Exit; 
end;   // parse parameters  if HasOption('h', 'help') then begin   
WriteHelp;    Terminate;    Exit;  end;   { add your program here }  
 connect_tcp;   terminate; end; constructor
TMyApplication.Create(ATCPClient: TTCPClient);begin // inherited
Create(TheOwner);  FTCPClient := ATCPClient; // FSettings :=
ASettings;  FTCPClient := TTCPClient.Create;  FTCPClient.OnRecvMessage
:= @DoOnRecvMessage;  FTCPClient.OnConnect:=@DoOnConnect;  StopOnExcep
tion:=True; end; destructor TMyApplication.Destroy;begin  inherited
Destroy;end; procedure Tfrclient.RecvMessage(Sender: TObject;AMsg:
String; AParams: TStringArray; {%H-}AConnection: TConnection;AddLog:
TAddLog);varrcv_msg : string;begin  writeln('what');   case AMsg of  
'TEXT':       begin          rcv_msg := AParams[0];         
writeln('waiting...');          readln(rcv_msg);       
end;end; end; procedure Tmyapplication.AddLog(ALogMsg: String);begin 
writeln('log added');end; procedure Tmyapplication.DoOnConnect(Sender:
TObject; AConnection:
TConnection);beginwriteln('connected');end; procedure
Tmyapplication.DoOnRecvMessage(Sender: TObject; AMsg: String; 
AParams: TStringArray; AConnection: TConnection);type  TAddLog =
procedure(ALogMsg: String) of Object;varAddLogCallback:
TAddLog;rcv_msg : string;FPCClient : Tfrclient;begin  FPCClient :=
Tfrclient.Create; FPCClient.RecvMessage(Sender, AMsg, AParams,
AConnection, AddLogCallBack);end;  procedure
Tmyapplication.sending(ATCPBase: TTCPBase; ATCPBaseType: TBaseType;
ASettings: TSettings; AConnection: TConnection);begin   // FTCPBase :=
TTCPBase.Create;   FTCPBase := ATCPBase;   FTCPBaseType :=
ATCPBaseType;   FSettings := ASettings;   Connection :=
AConnection;  trywriteln('sending a msg');FTCPBase.SendMessage('TEXT',
['8989898'], AConnection.FUniqueID);readln; except   
writeln('faild');end;end; procedure Tmyapplication.connect_tcp;var  //
 Connection: TConnection;    list : Tstringlist;    connection_status
: boolean;      MS: TMemoryStream;      bla:string;      chat :
Tmyapplication;begin FSettings :=Tsettings.Create; FTCPClient :=
TTCPClient.Create; if FTCPClient.Connected = false then  // begin 
 connection_status := false;     r_host := '127.0.0.1'; 
 FSettings.ActiveConnection.FIP := r_host; 
 FSettings.ActiveConnection.FPort := IntToStr(4433); 
FSettings.ActiveConnection.FUser := 'wtf'; 
 FSettings.ActiveConnection.FPass := '';   Connection :=
TConnection.Create; 
FSettings.CopyConnection(FSettings.activeConnection, Connection);   
r_host :=
connection.fip; FTCPClient.Connect(FSettings.ActiveConnection); while
FTCPClient.Connected do begin   writeln('ok'); end;  readln;  end;   
  
what I want ?
* able to receive command sent from the server-side again it is better
to have a look into this sample
(https://forum.lazarus.freepascal.org/index.php?topic=48677.0) i am
working on

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engkin · 2021-05-24 17:15

Your app needs to call CheckSynchronize in a loop inside DoRun, along
these lines:
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     While
not Terminated do    begin      Sleep(1);      CheckSynchronize;   
end;

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engkin · 2021-05-24 18:06

Disregard my previous reply. I had thought you already converted the
code to a console app before I replied.

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rvk · 2021-05-24 21:22

writeln and readln in a thread?
Wouldn't that cause lots of trouble?

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fpc2pas · 2021-05-25 03:43

Quote from: engkin on May 24, 2021, 08:06:27 pmDisregard my previous
reply. I had thought you already converted the code to a console app
before I replied.

still not, I have problems on porting the socket events to work
probably in console app mode not GUI

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fpc2pas · 2021-05-25 03:45

Quote from: rvk on May 24, 2021, 11:22:41 pmwriteln and readln in a
thread?
Wouldn't that cause lots of trouble?

this is still testing, first i have to get a workable version that can
receive strings from server and interact on events like Dononconnect
or DoonRecv

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fpc2pas · 2021-05-25 04:35

@engkin thanks i think the following function
CheckSynchronize; helped me to have the first simple working version

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fpc2pas · 2021-05-30 08:48

Quote from: engkin on May 24, 2021, 07:15:37 pmYour app needs to call
CheckSynchronize in a loop inside DoRun, along these lines:
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     While
not Terminated do    begin      Sleep(1);      CheckSynchronize;   
end;
I am just having access violation while using CheckSynchronize, do you
have an idea why that's happening? especially when sending a message
from the server into client multiple times, it shows access violation

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engkin · 2021-05-30 12:46

If you post the code you already have, it would make it easier to
pinpoint the problem. Don't forget to mention your OS, FPC
version..etc

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fpc2pas · 2021-05-30 14:04

Quote from: engkin on May 30, 2021, 02:46:09 pmIf you post the code
you already have, it would make it easier to pinpoint the problem.
Don't forget to mention your OS, FPC version..etc

I figured out whats the problem, it is not about CheckSynchronize, it
is about the TstringArray problem on @Recvmessage event, so for
example from server-side if you send the following send message
command HELP

 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
 FTCPBase.SendMessage('TEXT', [edText.Text], FConnection.FUniqueID);
while your onRecmessage function is like this
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
Tfrclient.RecvMessage(Sender: TObject;AMsg: String; AParams:
Tstringarray; {%H-}AConnection: TConnection);begin    case Aparams[0]
of    'HELP':       begin         write_help;        end;            
                                                                     
          
you will get an access violation if you send it multiple time, while
if you send a msg like this format from server-side it works with no
violation
HELP,,

I think it is a bug, but still not figure out how to resolve it

using windows 10 
FPC 3.2.0