sgcWebSocket Exception working with Arduino
lazarus / 38-Networking and Web Programming

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negagen · 2018-06-15 05:17

Hi guys, well the topic is this i'm trying to receive messages on
plain text from an arduino through websockets, i made the server with
sgcWebSockets, and i'm using the websockets client library that the
arduino IDE let you install, the problem is this trying only connect
to the websokect server i made i get this error:

Error Protocol: arduino
 not supported.

i tried to solve this using a subprotocol with the example code that
sgcWebSocket let you use:


unit ProtocoloArduino;

interface
{$I sgcVer.inc}

{$IFDEF SGC_PROTOCOLS}
uses
  sgcWebSocket_Protocol_Base_Server, Classes, sgcWebSocket_Classes;

type
  TsgcWSProtocol_Arduino = class(TsgcWSProtocol_Server_Base)

  { from TsgcWSComponent }
  protected
   procedure DoEventConnect(aConnection: TsgcWSConnection); override;
   procedure DoEventMessage(aConnection: TsgcWSConnection; const Text:
string); override;
   procedure DoEventDisconnect(aConnection: TsgcWSConnection; Code:
Integer); override;

  { from TsgcWSComponent }
  public
   constructor Create(aOwner: TComponent); override;
  end;
{$ENDIF}

implementation
{$IFDEF SGC_PROTOCOLS}

constructor TsgcWSProtocol_Arduino.Create(aOwner:TComponent);
begin
  inherited;
  // ... here add your protocol name
  FProtocol := 'arduino';
end;

procedure
TsgcWSProtocol_Arduino.DoEventConnect(aConnection:TsgcWSConnection);
begin
  inherited;
  // ... add your own code when a client connects to server
end;

procedure TsgcWSProtocol_Arduino.DoEventDisconnect(aConnection:
TsgcWSConnection; Code: Integer);
begin
  // ... add your own code when a client disconnects from server
  inherited;
end;

procedure TsgcWSProtocol_Arduino.DoEventMessage(aConnection:
TsgcWSConnection; const Text: string);
begin
  inherited;
  // ... process messages received from clients
  // ... you can answer to client using
  WriteData(aConnection.Guid, 'your message');
  // ... you can send a message to all clients using
  BroadCast('your message');
end;
{$ENDIF}
end.

but i didn't work registering this protocol either, looking in the
source code of sgcWebSocket the exception is throw here:

.....
{ RequestURL protocol }
  private
    function DoGetProtocol: string;
{ RequestURL protocol }

.....
function TsgcWSConnectionServer.DoGetProtocol: string;
var
  i: Integer;
  oSProtocols, oCProtocols: TsgcDelimitedStringList;
begin
  if FHandshake.Protocols <> '' then
  begin
    oSProtocols := TsgcDelimitedStringList.Create;
    oCProtocols := TsgcDelimitedStringList.Create;
    Try
      oSProtocols.DelimitedText := Protocol;

      oCProtocols.DelimitedText := FHandshake.Protocols;

      for i := 0 to oCProtocols.Count - 1 do
      begin
        if oSProtocols.IndexOf(oCProtocols) > -1 then
        begin
          Result := oCProtocols;
          break;
        end;
      end;

      if Result = '' then
        raise TsgcWSException.CreateFmt(S_PROTOCOL_UNSUPPORTED,
          [oCProtocols.Text]);

    Finally
      sgcFree(oCProtocols);
      sgcFree(oSProtocols);
    End;
  end;
end;

if somebody can help me i'll be grateful