4bnode/add-bonjour.js

4bnode is a CLI-powered backend development platform with a built-in visual dashboard to generate, manage, and test Node.js/Express APIs faster.

#!/usr/bin/env node

import fs from "fs";
import path from "path";
import { input } from "@inquirer/prompts";
import { getProjectRoot } from "./lib/project.js";
import { updateEnvFile } from "./lib/env.js";
import { readIndex, writeIndex } from "./lib/indexFile.js";
import {
  showHeader,
  showTaskDone,
  showError,
  showInfo,
  showFileAction,
  installDeps,
} from "./lib/ui.js";
import { buildDiscoveryModule, wireDiscoveryIntoIndex } from "./lib/codegen.js";

async function main() {
  showHeader("add-bonjour", "Advertise this app on the local network (Bonjour / mDNS)");

  showInfo(
    "Other devices on the same Wi-Fi/LAN can then reach this app by name " +
      "(http://<host>.local:<port>) — no hard-coded IPs. Works with Apple Bonjour, " +
      "Android/Windows/Linux mDNS, and the bonsoir Flutter plugin.",
  );

  const root = getProjectRoot();
  const envPath = path.join(root, ".env");
  const discoveryPath = path.join(root, "src", "discovery.js");

  const name = (
    await input({ message: "Service name (blank = app name + hostname):", default: "" })
  ).trim();
  const type = (
    await input({ message: "Service type (without the leading underscore):", default: "http" })
  ).trim() || "http";

  console.log();

  // 1. Write the discovery module from the single source of truth (codegen). It's
  //    deterministic, so re-running just refreshes the file in place.
  fs.mkdirSync(path.dirname(discoveryPath), { recursive: true });
  const existed = fs.existsSync(discoveryPath);
  fs.writeFileSync(discoveryPath, buildDiscoveryModule(), "utf8");
  showFileAction(existed ? "updated" : "created", "src/discovery.js");

  // 2. Wire it into index.js (idempotent — a no-op if already wired).
  try {
    const before = readIndex();
    const after = wireDiscoveryIntoIndex(before);
    if (after !== before) {
      writeIndex(after);
      showFileAction("updated", "index.js");
    } else {
      showInfo("index.js is already wired for discovery — leaving it as is.");
    }
  } catch (e) {
    showInfo(
      "Could not auto-wire index.js (" +
        e.message +
        "). Import { startAdvertising, destroyDiscovery } from './src/discovery.js' " +
        "and call startAdvertising({ port }) after your server starts listening.",
    );
  }

  // 3. Configuration in .env.
  updateEnvFile(envPath, "BONJOUR_ENABLED", "on");
  if (name) updateEnvFile(envPath, "BONJOUR_NAME", name);
  if (type && type !== "http") updateEnvFile(envPath, "BONJOUR_TYPE", type);
  showFileAction("updated", ".env");

  // 4. Dependency (records it in package.json even if the install is offline).
  await installDeps("bonjour-service");

  showTaskDone("Bonjour / mDNS discovery enabled", [
    name ? `Service name: ${name}` : "Service name: app name + hostname",
    `Service type: _${type}._tcp`,
    "Advertises once the server is listening; sends goodbye packets on clean shutdown",
    "Browse peers on the network from the /_dev dashboard → Discovery",
    "Disable anytime with BONJOUR_ENABLED=off in .env",
  ]);
}

main().catch((err) => {
  if (err.name === "ExitPromptError") process.exit(0);
  showError(err.message);
  process.exit(1);
});