FiveM - resource hot reload

One repetitive task often disrupts you when you developing your FiveM resource: the resource reloading.

Indeed each time you make a change to your code, you need to run restart <resName> in the FiveM console inside the game. This process, while functional, is a time sink that adds up, especially when working on complex projects.

Wouldn't it be great if FiveM development could adopt a similar hot-reload mechanism of webapp? Let’s dive into the problem and explore how to create a hot-reload solution.

Conception

To run restart <resName> command, we can use the method ExecuteCommand provided by FiveM inside resource scripts. We also need an entry point to trigger this restart. In my side, I choose an http server (but other type of server can work).

My JS Hot-reload source code

I did it in JS because it's my main language but you can do it with Lua or C#.

TAKE CARE: Give the right permissio needed to run restart command //todo

const http = require("http");

// Set the port for the HTTP server
const PORT = 3000;

// Create the HTTP server
const server = http.createServer((req, res) => {
  console.log("url", req.url);

  if (req.method !== "POST" || !req.url?.startsWith("/restart?resource=")) {
    res.writeHead(400, { "Content-Type": "text/plain" });
    res.end("Invalid request");
    return;
  }

  const resource = new URLSearchParams(req.url.split("?")[1]).get("resource");

  console.log("Resource to restart:", resource);

  if (resource !== "hot-reload") {
    ExecuteCommand(`restart ${resource}`);
  }

  // Handle the response
  res.writeHead(200, { "Content-Type": "text/plain" });
  res.end("Resource restarted");
});

// Start the server
server.listen(PORT, "0.0.0.0", () => {
  console.log(`HTTP Server running on port ${PORT}`);
});

How to detect when trigger hot-reload

For people using Javascript or Typescript, I assume you have a bundler tool like explained in this article

You can easily create a custom plugin to do it

function pluginTriggerFivemResourceRestart() {
  return {
    name: "trigger-fivem-resource-restart", // Name of the plugin
    closeBundle() {
      const resourceName = "<resName>"

      // Restart the resource by make a POST request with JSON data
      fetch(`http://localhost:3000/restart?resource=${resourceName}`, {
        method: "POST",
      });
    },
  };
}

For lua resource, a simple "watcher" like glob-watcher to check changes for *.lua files and run fetch request on change is "sufficient"

To go further

If you are in PNPM workspace with multiple typescript resources dependent on each other, you will find a way to create an efficient watch mode to automize dependencies rebuild.