fix: wait for extracted binary to close before spawning (Windows EBUSY) [TE-27044]

.github/workflows/binary-spawn-check.yml

@@ -0,0 +1,23 @@
+name: Binary extract and spawn check
+on:
+  push:
+  pull_request:
+
+jobs:
+  spawn:
+    runs-on: ${{ matrix.os }}
+    timeout-minutes: 20
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [windows-latest, ubuntu-latest, macos-latest]
+        node: [18, 22]
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node }}
+      - run: npm install --omit=dev --no-audit --no-fund
+      - run: node scripts/check-binary-spawn.js 15
+      - name: Spawn check with slow binary close (simulated AV scan-on-close)
+        run: node -r ./scripts/slow-close.js scripts/check-binary-spawn.js 5

lib/cfg/node-tunnel-config-v3-latest.json

@@ -63,20 +63,20 @@
                {
                    "httpPath": "https://downloads.lambdatest.com/tunnel/v3/freebsd/32bit/LT_Freebsd.zip",
                    "binaryName": "LT_Freebsd.zip",
-                   "hash": "3525242664a3a24aa9e49969d137dadb"
+                   "hash": "0747869934c7838e1e812d508c242d50"
                },
                "64bit":
                {
                    "httpPath": "https://downloads.lambdatest.com/tunnel/v3/freebsd/64bit/LT_Freebsd.zip",
                    "binaryName": "LT_Freebsd.zip",
-                   "hash": "e5fec50196cd1fa02306bdd74acccea3"
+                   "hash": "5a64de0bf4e821da8ddf26c830fc322a"
                }
            }
        }
    },
    "AuthUrl": "https://accounts.lambdatest.com/api/user/token/auth",
    "logEnable": true,
-   "latest": "4.0.12",
+   "latest": "4.0.14",
    "supportedVersions":
    [
        "1.0.0",
@@ -125,6 +125,8 @@
        "4.0.9",
        "4.0.10",
        "4.0.11",
-       "4.0.12"
+       "4.0.12",
+       "4.0.13",
+       "4.0.14"
    ]
 }

lib/tunnel_binary.js

@@ -140,7 +140,20 @@ function TunnelBinary(httpTunnelConfig, options) {
               console.log(`Extracting binary`);
               var zip = new StreamZip.async({ file: binaryPath });
               zip
-                .extract(null, path.resolve(destParentDir))
+                .stream(destBinaryName)
+                .then(function(entryStream) {
+                  // Resolve on 'close', not 'finish': spawning before the fd closes fails with EBUSY on Windows.
+                  return new Promise(function(resolve, reject) {
+                    var out = fs.createWriteStream(destBinaryPath);
+                    entryStream.on('error', function(e) {
+                      out.destroy();
+                      reject(e);
+                    });
+                    out.on('error', reject);
+                    out.on('close', resolve);
+                    entryStream.pipe(out);
+                  });
+                })
                 .then(function() {
                   return zip.close();
                 })

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@lambdatest/node-tunnel",
-  "version": "4.0.13",
+  "version": "4.0.14",
   "description": "Nodejs bindings for LambdaTest Tunnel",
   "main": "index.js",
   "files": [

scripts/check-binary-spawn.js

@@ -0,0 +1,46 @@
+// Downloads and extracts the tunnel binary into a fresh dir, then spawns it immediately (as Tunnel.start does), N times.
+var fs = require('fs'),
+  os = require('os'),
+  path = require('path'),
+  childProcess = require('child_process'),
+  TunnelBinary = require('../lib/tunnel_binary'),
+  cfg = require('../lib/cfg/node-tunnel-config-v3-latest.json');
+
+var runs = Number(process.argv[2]) || 10;
+var failures = 0;
+
+function once(i, done) {
+  var tb = new TunnelBinary({ jsonResponse: cfg, logger: { log: function() {} } }, {});
+  var dir = fs.mkdtempSync(path.join(os.tmpdir(), 'lt-'));
+  var timer = setTimeout(function() {
+    done(new Error('timed out waiting for download/extract'));
+  }, 120000);
+  tb.download_({}, dir, 1, function(binaryPath) {
+    clearTimeout(timer);
+    var proc;
+    try {
+      proc = childProcess.spawn(binaryPath, ['--help'], { stdio: 'ignore' });
+    } catch (e) {
+      return done(e);
+    }
+    proc.on('error', done);
+    proc.on('spawn', function() {
+      proc.kill();
+      done();
+    });
+  });
+}
+
+function next(i) {
+  if (i > runs) {
+    console.log('RESULT ' + (runs - failures) + '/' + runs + ' spawned ok');
+    process.exit(failures ? 1 : 0);
+  }
+  once(i, function(err) {
+    if (err) failures++;
+    console.log('run ' + i + ': ' + (err ? 'FAIL ' + (err.code || err.message) : 'ok'));
+    next(i + 1);
+  });
+}
+
+next(1);

scripts/slow-close.js

@@ -0,0 +1,25 @@
+// Preload that delays closing the extracted LT binary by 800ms, mimicking real-time AV scan-on-close on Windows.
+var fs = require('fs');
+var binaryFds = {};
+var origOpen = fs.open;
+var origClose = fs.close;
+
+fs.open = function(file) {
+  var args = Array.prototype.slice.call(arguments);
+  var cb = args[args.length - 1];
+  args[args.length - 1] = function(err, fd) {
+    if (!err && /[\\/]LT(\.exe)?$/.test(String(file))) binaryFds[fd] = true;
+    cb(err, fd);
+  };
+  return origOpen.apply(fs, args);
+};
+
+fs.close = function(fd, cb) {
+  if (binaryFds[fd]) {
+    delete binaryFds[fd];
+    return setTimeout(function() {
+      origClose.call(fs, fd, cb);
+    }, 800);
+  }
+  return origClose.apply(fs, arguments);
+};