Indy/Lib/Source/IdGopherServer.pas

{
  $Project$
  $Workfile$
  $Revision$
  $DateUTC$
  $Id$

  This file is part of the Indy (Internet Direct) project, and is offered
  under the dual-licensing agreement described on the Indy website.
  (http://www.indyproject.org/)

  Copyright:
   (c) 1993-2005, Chad Z. Hower and the Indy Pit Crew. All rights reserved.
}
{
  $Log$
}
{
  Rev 1.7    12/2/2004 4:23:54 PM  JPMugaas
  Adjusted for changes in Core.

  Rev 1.6    2004.02.03 5:44:48 PM  czhower
  Name changes

  Rev 1.5    1/21/2004 3:26:46 PM  JPMugaas
  InitComponent

  Rev 1.4    2/24/2003 08:54:00 PM  JPMugaas

  Rev 1.3    1/17/2003 07:10:26 PM  JPMugaas
  Now compiles under new framework.

  Rev 1.2    1-1-2003 20:13:12  BGooijen
  Changed to support the new TIdContext class

  Rev 1.1    12/6/2002 04:35:10 PM  JPMugaas
  Now compiles with new code.

  Rev 1.0    11/13/2002 08:30:20 AM  JPMugaas
  Initial import from FTP VC.

  2000-Apr-29 Pete Mee
  - Converted to new Indy format.

  1999-Oct-03 Pete Mee
  - Gopher server is very basic... started & completed...
}

unit IdGopherServer;

interface

{$i IdCompilerDefines.inc}

uses
  Classes,
  IdAssignedNumbers,
  IdContext,
  IdCustomTCPServer,
  IdGlobal;

{
  Typical connection:
  - Client attaches with no data
  - Server accepts with no data
  - Client sends request with CR LF termate (CRLF only for root)
  - Server sends items available each with CRLF termating
  - Server sends .CRLF
  - Server close connection
}

type
  TRequestEvent = procedure(AContext: TIdContext; ARequest: String) of object;
  TPlusRequestEvent = procedure(AContext: TIdContext; ARequest: String; APlusData: String) of object;

  TIdGopherServer = class(TIdCustomTCPServer)
  private
    fAdminEmail : String;

    fOnRequest : TRequestEvent;
    fOnPlusRequest : TPlusRequestEvent;

    fTruncateUserFriendly : Boolean;
    fTruncateLength : Integer;
  protected
    function DoExecute(AContext: TIdContext): Boolean; override;
  public
    constructor Create(AOwner: TComponent); override;
    function ReturnGopherItem(ItemType : Char;
      UserFriendlyName, RealResourceName : String;
      HostServer : String; HostPort : TIdPort): String;
    procedure SendDirectoryEntry(AContext:TIdContext;
      ItemType : Char; UserFriendlyName, RealResourceName : String;
      HostServer : String; HostPort : TIdPort);
  published
    property AdminEmail : String read fAdminEmail write fAdminEmail;
    property OnRequest: TRequestEvent read fOnRequest write fOnRequest;
    property OnPlusRequest : TPlusRequestEvent read fOnPlusRequest
      write fOnPlusRequest;
    property TruncateUserFriendlyName : Boolean read fTruncateUserFriendly
      write fTruncateUserFriendly default True;
    property TruncateLength : Integer read fTruncateLength
      write fTruncateLength default 70;
    property DefaultPort default IdPORT_GOPHER;
  end;

implementation

uses
  IdGopherConsts, IdResourceStringsProtocols, SysUtils;

constructor TIdGopherServer.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  DefaultPort := IdPORT_GOPHER;
  fAdminEmail := '<[email protected]>';    {Do not Localize}
  fTruncateUserFriendly := True;
  fTruncateLength := 70;
end;

function TIdGopherServer.DoExecute(AContext: TIdContext): boolean;
var
  s : String;
  i : Integer;
begin
  Result := True;
  s := AContext.Connection.IOHandler.ReadLn;
  i := Pos(TAB, s);
  if i > 0 then begin
    // Is a Gopher+ request
    if Assigned(OnPlusRequest) then begin
      OnPlusRequest(AContext, Copy(s, 1, i - 1), Copy(s, i + 1, Length(s)));
    end else if Assigned(OnRequest) then begin
      OnRequest(AContext, s);
    end else begin
      AContext.Connection.IOHandler.Write(
        IdGopherPlusData_ErrorBeginSign
        + IdGopherPlusError_NotAvailable
        + RSGopherServerNoProgramCode + EOL
        + IdGopherPlusData_EndSign);
    end;
  end else if Assigned(OnRequest) then begin
    OnRequest(AContext, s);
  end else begin
    AContext.Connection.IOHandler.Write(RSGopherServerNoProgramCode + EOL + IdGopherPlusData_EndSign);
  end;
  AContext.Connection.Disconnect;
end;

function TIdGopherServer.ReturnGopherItem(ItemType : Char;
  UserFriendlyName, RealResourceName : String;
  HostServer : String; HostPort : TIdPort): String;
begin
  if fTruncateUserFriendly then begin
    if (Length(UserFriendlyName) > fTruncateLength) and (fTruncateLength <> 0) then begin
      UserFriendlyName := Copy(UserFriendlyName, 1, fTruncateLength);
    end;
  end;
  Result := ItemType + UserFriendlyName +
    TAB + RealResourceName + TAB + HostServer + TAB + IntToStr(HostPort);
end;

procedure TIdGopherServer.SendDirectoryEntry;
{
Format of server reply to directory (assume no spacing between - i.e.,
one line, with CR LF at the end)
 - Item Type
 - User Description (without tab characters)
 - Tab
 - Server-assigned string to this individual Item Type resource
 - Tab
 - Domain Name of host
 - Tab
 - Port # of host
}
begin
  AContext.Connection.IOHandler.WriteLn(
    ReturnGopherItem(ItemType, UserFriendlyName, RealResourceName, HostServer, HostPort)
  );
end;

end.