HTTP Server (non-SSL) hangs on Linux - OnGet event never fires - Windows Work #165
Description
Hello,
I'm having trouble getting the TCrossWebSocketServer (from the Delphi-Cross-Socket library) to work on Linux. It works perfectly on Windows 11.
My goal is to run a non-SSL HTTP server (Create(2, False)).
The Environment
Delphi: Delphi 11
Linux: Alma Linux 8 (RHEL 8 clone)
DCS Library: Latest version from GitHub.
OpenSSL: System version is 1.1. (compat-openssl11 is installed).
The Problem
The server starts correctly and opens the port (I can see this in the OnServerListen log and netstat).
However, when I try to connect from a client (like wget http://127.0.0.1:8080), the client connects successfully but then hangs, "awaiting response" indefinitely.
Crucially, the server never fires the OnGet event. The log message inside LServer.Get('/', ...) is never printed.
What I've Tested
-
Windows 11: The exact same minimal test project (code below) works perfectly.
-
Oracle Linux 8 (VM): Fails (hangs).
-
Alma Linux 9 (WSL): Fails (hangs).
-
Firewall: The firewall (firewalld) is disabled on the Linux machine.
-
Indy Test: A separate TIdTCPServer (Indy) on port 9000 in the same application works perfectly on Linux. The problem seems specific to the DCS library.
-
Official Demo: I also tested the official WebSocketServer.dpr demo. It works on Windows (using wss://) but fails with the same hang on Linux.
Minimal Test Code (DCSTest.dpr)
This is the minimal console application I am using to test. It has no threads, no critical sections, and no other libraries.
program DCSTest;
{$APPTYPE CONSOLE}
uses
System.SysUtils,
Net.CrossSocket.Base,
Net.CrossHttpServer,
Net.CrossWebSocketServer,
Net.CrossWebSocketParser;
var
LServer: ICrossWebSocketServer;
begin
Writeln('[DCS TEST] Starting test server...');
try
LServer := TCrossWebSocketServer.Create(2, False); // Non-SSL
LServer.Port := 8080;
LServer.Start(
procedure(const AListen: ICrossListen; const ASuccess: Boolean)
begin
if ASuccess then
Writeln('[DCS TEST] SERVER STARTED on [', AListen.LocalAddr, ':', AListen.LocalPort, ']')
else
Writeln('[DCS TEST] ERROR: Server could not start.');
end);
LServer.Get('/',
procedure(const ARequest: ICrossHttpRequest; const AResponse: ICrossHttpResponse; var AHandled: Boolean)
begin
// --- THIS LOG NEVER APPEARS ON LINUX ---
Writeln('[DCS TEST] HTTP GET Request Received!');
AResponse.ContentType := 'text/html';
AResponse.Send('<html><body><h1>DCS Test OK</h1></body></html>');
AHandled := True;
end);
Writeln('[DCS TEST] Server is running. Press Enter to exit.');
Readln;
LServer.Stop;
LServer := nil;
except
on E: Exception do
Writeln('FATAL ERROR: ' + E.Message);
end;
Writeln('[DCS TEST] Exiting.');
end.
Log output on Linux:
[DCS TEST] Starting test server...
[DCS TEST] SERVER STARTED on [0.0.0.0:8080]
[DCS TEST] SERVER STARTED on [:::8080]
[DCS TEST] Server is running. Press Enter to exit.
(Hangs here.wgetconnects, but the "HTTP GET Request Received!" log never appears)