Filesystem watcher refactoring

Don't use child process for resource watcher.

Author: seregazhuk

CHANGELOG.md

@@ -1,3 +1,6 @@
+## 0.6.0 (2020-05-11)
+* Fix: don't use child process for resource watching
+
 ## 0.5.2 (2019-12-07)
 * Fix: use predefined const for PHP binary [#59](https://github.com/seregazhuk/php-watcher/pull/59)
 * Fix: increase dependency options [#58](https://github.com/seregazhuk/php-watcher/pull/58) by @mmoreram 

src/Filesystem/ChangesListener.php

@@ -10,41 +10,26 @@
 
 final class ChangesListener extends EventEmitter
 {
-    private const WATCHER_SCRIPT = '/watcher.php';
+    private const INTERVAL = 0.15;
 
     private $loop;
 
-    private $watchList;
-
-    public function __construct(LoopInterface $loop, WatchList $watchList)
+    public function __construct(LoopInterface $loop)
     {
         $this->loop = $loop;
-        $this->watchList = $watchList;
-    }
-
-    public function start(): void
-    {
-        $watcherProcess = new Process($this->scriptToRun());
-        $watcherProcess->start($this->loop);
-
-        $this->handleOutput($watcherProcess);
     }
 
-    private function handleOutput(Process $process): void
+    public function start(WatchList $watchList): void
     {
-        if ($process->stdout === null) {
-            throw new RuntimeException('Cannot open STDOUT for filesystem watcher');
-        }
-
-        $process->stdout->on('data', function (string $data) {
-            if ((bool)$data) {
-                $this->emit('change');
+        $watcher = ResourceWatcherBuilder::create($watchList);
+
+        $this->loop->addPeriodicTimer(
+            self::INTERVAL,
+            function () use ($watcher) {
+                if ($watcher->findChanges()->hasChanges()) {
+                    $this->emit('change');
+                }
             }
-        });
-    }
-
-    private function scriptToRun(): string
-    {
-        return sprintf('exec php %s "%s"', __DIR__ . self::WATCHER_SCRIPT, addslashes($this->watchList->toJson()));
+        );
     }
 }

src/Filesystem/ResourceWatcherFactory.php renamed to src/Filesystem/ResourceWatcherBuilder.php

@@ -8,7 +8,7 @@
 use Yosymfony\ResourceWatcher\ResourceCacheMemory;
 use Yosymfony\ResourceWatcher\ResourceWatcher;
 
-final class ResourceWatcherFactory
+final class ResourceWatcherBuilder
 {
     public static function create(WatchList $watchList): ResourceWatcher
     {

src/Filesystem/watcher.php

@@ -1,8 +1,10 @@
-<?php declare(strict_types=1);
+<?php
+declare(strict_types=1);
 
 namespace seregazhuk\PhpWatcher;
 
 use React\EventLoop\LoopInterface;
+use seregazhuk\PhpWatcher\Config\WatchList;
 use seregazhuk\PhpWatcher\Filesystem\ChangesListener;
 
 final class Watcher
@@ -17,15 +19,22 @@ public function __construct(LoopInterface $loop, ChangesListener $filesystemList
         $this->filesystemListener = $filesystemListener;
     }
 
-    public function startWatching(ProcessRunner $processRunner, int $signal, float $delayToRestart): void
-    {
+    public function startWatching(
+        ProcessRunner $processRunner,
+        WatchList $watchList,
+        int $signal,
+        float $delayToRestart
+    ): void {
         $processRunner->start();
 
-        $this->filesystemListener->start();
-        $this->filesystemListener->on('change', static function () use ($processRunner, $signal, $delayToRestart) {
-            $processRunner->stop($signal);
-            $processRunner->restart($delayToRestart);
-        });
+        $this->filesystemListener->start($watchList);
+        $this->filesystemListener->on(
+            'change',
+            static function () use ($processRunner, $signal, $delayToRestart) {
+                $processRunner->stop($signal);
+                $processRunner->restart($delayToRestart);
+            }
+        );
 
         $this->loop->run();
     }

src/Watcher.php

@@ -1,4 +1,5 @@
-<?php declare(strict_types=1);
+<?php
+declare(strict_types=1);
 
 namespace seregazhuk\PhpWatcher;
 
@@ -25,13 +26,30 @@ protected function configure(): void
         $this->setName('watch')
             ->setDescription('Restart PHP application once the source code changes.')
             ->addArgument('script', InputArgument::REQUIRED, 'Script to run')
-            ->addOption('watch', '-w', InputOption::VALUE_IS_ARRAY + InputOption::VALUE_OPTIONAL, 'Paths to watch')
+            ->addOption(
+                'watch',
+                '-w',
+                InputOption::VALUE_IS_ARRAY + InputOption::VALUE_OPTIONAL,
+                'Paths to watch'
+            )
             ->addOption('ext', '-e', InputOption::VALUE_OPTIONAL, 'Extensions to watch', '')
-            ->addOption('ignore', '-i', InputOption::VALUE_IS_ARRAY + InputOption::VALUE_OPTIONAL, 'Paths to ignore', [])
+            ->addOption(
+                'ignore',
+                '-i',
+                InputOption::VALUE_IS_ARRAY + InputOption::VALUE_OPTIONAL,
+                'Paths to ignore',
+                []
+            )
             ->addOption('exec', null, InputOption::VALUE_OPTIONAL, 'PHP executable')
             ->addOption('delay', null, InputOption::VALUE_OPTIONAL, 'Delaying restart')
             ->addOption('signal', null, InputOption::VALUE_OPTIONAL, 'Signal to reload the app')
-            ->addOption('arguments', null, InputOption::VALUE_IS_ARRAY + InputOption::VALUE_OPTIONAL, 'Arguments for the script', [])
+            ->addOption(
+                'arguments',
+                null,
+                InputOption::VALUE_IS_ARRAY + InputOption::VALUE_OPTIONAL,
+                'Arguments for the script',
+                []
+            )
             ->addOption('config', null, InputOption::VALUE_OPTIONAL, 'Path to config file')
             ->addOption('no-spinner', null, InputOption::VALUE_NONE, 'Remove spinner from output');
     }
@@ -45,13 +63,18 @@ protected function execute(InputInterface $input, OutputInterface $output)
         $this->addTerminationListeners($loop, $spinner);
 
         $screen = new Screen(new SymfonyStyle($input, $output), $spinner);
-        $filesystem = new ChangesListener($loop, $config->watchList());
+        $filesystem = new ChangesListener($loop);
 
         $screen->showOptions($config->watchList());
         $processRunner = new ProcessRunner($loop, $screen, $config->command());
 
         $watcher = new Watcher($loop, $filesystem);
-        $watcher->startWatching($processRunner, $config->signalToReload(), $config->delay());
+        $watcher->startWatching(
+            $processRunner,
+            $config->watchList(),
+            $config->signalToReload(),
+            $config->delay()
+        );
 
         return 0;
     }

src/WatcherCommand.php

@@ -18,8 +18,8 @@ final class ChangesListenerTest extends TestCase
     public function it_emits_change_event_on_changes(): void
     {
         $loop = Factory::create();
-        $listener = new ChangesListener($loop, new WatchList([Filesystem::fixturesDir()]));
-        $listener->start();
+        $listener = new ChangesListener($loop);
+        $listener->start(new WatchList([Filesystem::fixturesDir()]));
 
         $loop->addTimer(1, [Filesystem::class, 'createHelloWorldPHPFile']);
         $eventWasEmitted = false;

tests/Feature/ChangesListenerTest.php

@@ -9,7 +9,7 @@ abstract class WatcherTestCase extends TestCase
 {
     use WithFilesystem;
 
-    private const WAIT_TIMEOUT_MS = 2500000;
+    private const WAIT_TIMEOUT_MS = 5000000;
 
     /**
      * @var Process

tests/Feature/Helper/WatcherTestCase.php

@@ -28,6 +28,7 @@ public function it_reloads_by_changes_in_a_watched_dir(): void
 
         Filesystem::changeFileContentsWith($fileToWatch, '<?php echo "Something changed"; ');
         $this->wait();
+
         $this->assertOutputContains('restarting due to changes...');
     }
 }