Add executeAsync to ProcessExecutor and allow Loop class to wait on it in addition to HttpDownloader

src/Composer/Factory.php

@@ -336,7 +336,7 @@ class Factory
 
         $httpDownloader = self::createHttpDownloader($io, $config);
         $process = new ProcessExecutor($io);
-        $loop = new Loop($httpDownloader);
+        $loop = new Loop($httpDownloader, $process);
         $composer->setLoop($loop);
 
         // initialize event dispatcher

src/Composer/Util/HttpDownloader.php

@@ -44,6 +44,7 @@ class HttpDownloader
     private $rfs;
     private $idGen = 0;
     private $disabled;
+    private $allowAsync = false;
 
     /**
      * @param IOInterface $io         The IO instance
@@ -139,6 +140,10 @@ class HttpDownloader
             'origin' => Url::getOrigin($this->config, $request['url']),
         );
 
+        if (!$sync && !$this->allowAsync) {
+            throw new \LogicException('You must use the HttpDownloader instance which is part of a Composer\Loop instance to be able to run async http requests');
+        }
+
         // capture username/password from URL if there is one
         if (preg_match('{^https?://([^:/]+):([^@/]+)@([^/]+)}i', $request['url'], $match)) {
             $this->io->setAuthentication($job['origin'], rawurldecode($match[1]), rawurldecode($match[2]));
@@ -189,7 +194,6 @@ class HttpDownloader
 
             // TODO 3.0 this should be done directly on $this when PHP 5.3 is dropped
             $downloader->markJobDone();
-            $downloader->scheduleNextJob();
 
             return $response;
         }, function ($e) use (&$job, $downloader) {
@@ -197,7 +201,6 @@ class HttpDownloader
             $job['exception'] = $e;
 
             $downloader->markJobDone();
-            $downloader->scheduleNextJob();
 
             throw $e;
         });
@@ -251,13 +254,7 @@ class HttpDownloader
     public function markJobDone()
     {
         $this->runningJobs--;
-    }
 
-    /**
-     * @private
-     */
-    public function scheduleNextJob()
-    {
         foreach ($this->jobs as $job) {
             if ($job['status'] === self::STATUS_QUEUED) {
                 $this->startJob($job['id']);
@@ -268,34 +265,50 @@ class HttpDownloader
         }
     }
 
-    public function wait($index = null, $progress = false)
+    public function wait($index = null)
     {
         while (true) {
+            if (!$this->hasActiveJob($index)) {
+                return;
+            }
+
+            usleep(1000);
+        }
+    }
+
+    /**
+     * @internal
+     */
+    public function enableAsync()
+    {
+        $this->allowAsync = true;
+    }
+
+    /**
+     * @internal
+     */
+    public function hasActiveJob($index = null)
+    {
         if ($this->curl) {
             $this->curl->tick();
         }
 
         if (null !== $index) {
             if ($this->jobs[$index]['status'] === self::STATUS_COMPLETED || $this->jobs[$index]['status'] === self::STATUS_FAILED) {
-                    return;
+                return false;
             }
-            } else {
+            return true;
-                $done = true;
+        }
+
         foreach ($this->jobs as $job) {
             if (!in_array($job['status'], array(self::STATUS_COMPLETED, self::STATUS_FAILED), true)) {
-                        $done = false;
+                return true;
-                        break;
             } elseif (!$job['sync']) {
                 unset($this->jobs[$job['id']]);
             }
         }
-                if ($done) {
-                    return;
-                }
-            }
 
-            usleep(1000);
+        return false;
-        }
     }
 
     private function getResponse($index)

src/Composer/Util/Loop.php

@@ -21,10 +21,19 @@ use React\Promise\Promise;
 class Loop
 {
     private $httpDownloader;
+    private $processExecutor;
+    private $currentPromises;
 
-    public function __construct(HttpDownloader $httpDownloader)
+    public function __construct(HttpDownloader $httpDownloader = null, ProcessExecutor $processExecutor = null)
     {
         $this->httpDownloader = $httpDownloader;
+        if ($this->httpDownloader) {
+            $this->httpDownloader->enableAsync();
+        }
+        $this->processExecutor = $processExecutor;
+        if ($this->processExecutor) {
+            $this->processExecutor->enableAsync();
+        }
     }
 
     public function wait(array $promises)
@@ -39,8 +48,30 @@ class Loop
             }
         );
 
-        $this->httpDownloader->wait();
+        $this->currentPromises = $promises;
 
+        while (true) {
+            $hasActiveJob = false;
+
+            if ($this->httpDownloader) {
+                if ($this->httpDownloader->hasActiveJob()) {
+                    $hasActiveJob = true;
+                }
+            }
+            if ($this->processExecutor) {
+                if ($this->processExecutor->hasActiveJob()) {
+                    $hasActiveJob = true;
+                }
+            }
+
+            if (!$hasActiveJob) {
+                break;
+            }
+
+            usleep(5000);
+        }
+
+        $this->currentPromises = null;
         if ($uncaught) {
             throw $uncaught;
         }

src/Composer/Util/ProcessExecutor.php

@@ -16,18 +16,32 @@ use Composer\IO\IOInterface;
 use Symfony\Component\Process\Process;
 use Symfony\Component\Process\ProcessUtils;
 use Symfony\Component\Process\Exception\RuntimeException;
+use React\Promise\Promise;
 
 /**
  * @author Robert Schönthal <seroscho@googlemail.com>
+ * @author Jordi Boggiano <j.boggiano@seld.be>
  */
 class ProcessExecutor
 {
+    const STATUS_QUEUED = 1;
+    const STATUS_STARTED = 2;
+    const STATUS_COMPLETED = 3;
+    const STATUS_FAILED = 4;
+    const STATUS_ABORTED = 5;
+
     protected static $timeout = 300;
 
     protected $captureOutput;
     protected $errorOutput;
     protected $io;
 
+    private $jobs = array();
+    private $runningJobs = 0;
+    private $maxJobs = 10;
+    private $idGen = 0;
+    private $allowAsync = false;
+
     public function __construct(IOInterface $io = null)
     {
         $this->io = $io;
@@ -112,6 +126,196 @@ class ProcessExecutor
         return $process->getExitCode();
     }
 
+    /**
+     * starts a process on the commandline in async mode
+     *
+     * @param  string $command the command to execute
+     * @param  mixed  $output  the output will be written into this var if passed by ref
+     *                         if a callable is passed it will be used as output handler
+     * @param  string $cwd     the working directory
+     * @return int    statuscode
+     */
+    public function executeAsync($command, $cwd = null)
+    {
+        if (!$this->allowAsync) {
+            throw new \LogicException('You must use the ProcessExecutor instance which is part of a Composer\Loop instance to be able to run async processes');
+        }
+
+        $job = array(
+            'id' => $this->idGen++,
+            'status' => self::STATUS_QUEUED,
+            'command' => $command,
+            'cwd' => $cwd,
+        );
+
+        $resolver = function ($resolve, $reject) use (&$job) {
+            $job['status'] = ProcessExecutor::STATUS_QUEUED;
+            $job['resolve'] = $resolve;
+            $job['reject'] = $reject;
+        };
+
+        $self = $this;
+        $io = $this->io;
+
+        $canceler = function () use (&$job) {
+            if ($job['status'] === self::STATUS_QUEUED) {
+                $job['status'] = self::STATUS_ABORTED;
+            }
+            if ($job['status'] !== self::STATUS_STARTED) {
+                return;
+            }
+            $job['status'] = self::STATUS_ABORTED;
+            try {
+                if (defined('SIGINT')) {
+                    $job['process']->signal(SIGINT);
+                }
+            } catch (\Exception $e) {
+                // signal can throw in various conditions, but we don't care if it fails
+            }
+            $job['process']->stop(1);
+        };
+
+        $promise = new Promise($resolver, $canceler);
+        $promise = $promise->then(function () use (&$job, $self) {
+            if ($job['process']->isSuccessful()) {
+                $job['status'] = ProcessExecutor::STATUS_COMPLETED;
+            } else {
+                $job['status'] = ProcessExecutor::STATUS_FAILED;
+            }
+
+            // TODO 3.0 this should be done directly on $this when PHP 5.3 is dropped
+            $self->markJobDone();
+
+            return $job['process'];
+        }, function () use (&$job, $self) {
+            $job['status'] = ProcessExecutor::STATUS_FAILED;
+
+            $self->markJobDone();
+
+            return \React\Promise\reject($job['process']);
+        });
+        $this->jobs[$job['id']] =& $job;
+
+        if ($this->runningJobs < $this->maxJobs) {
+            $this->startJob($job['id']);
+        }
+
+        return $promise;
+    }
+
+    private function startJob($id)
+    {
+        $job =& $this->jobs[$id];
+        if ($job['status'] !== self::STATUS_QUEUED) {
+            return;
+        }
+
+        // start job
+        $job['status'] = self::STATUS_STARTED;
+        $this->runningJobs++;
+
+        $command = $job['command'];
+        $cwd = $job['cwd'];
+
+        if ($this->io && $this->io->isDebug()) {
+            $safeCommand = preg_replace_callback('{://(?P<user>[^:/\s]+):(?P<password>[^@\s/]+)@}i', function ($m) {
+                if (preg_match('{^[a-f0-9]{12,}$}', $m['user'])) {
+                    return '://***:***@';
+                }
+
+                return '://'.$m['user'].':***@';
+            }, $command);
+            $safeCommand = preg_replace("{--password (.*[^\\\\]\') }", '--password \'***\' ', $safeCommand);
+            $this->io->writeError('Executing async command ('.($cwd ?: 'CWD').'): '.$safeCommand);
+        }
+
+        // make sure that null translate to the proper directory in case the dir is a symlink
+        // and we call a git command, because msysgit does not handle symlinks properly
+        if (null === $cwd && Platform::isWindows() && false !== strpos($command, 'git') && getcwd()) {
+            $cwd = realpath(getcwd());
+        }
+
+        // TODO in v3, commands should be passed in as arrays of cmd + args
+        if (method_exists('Symfony\Component\Process\Process', 'fromShellCommandline')) {
+            $process = Process::fromShellCommandline($command, $cwd, null, null, static::getTimeout());
+        } else {
+            $process = new Process($command, $cwd, null, null, static::getTimeout());
+        }
+
+        $job['process'] = $process;
+
+        $process->start();
+    }
+
+    public function wait($index = null)
+    {
+        while (true) {
+            if (!$this->hasActiveJob($index)) {
+                return;
+            }
+
+            usleep(1000);
+        }
+    }
+
+    /**
+     * @internal
+     */
+    public function enableAsync()
+    {
+        $this->allowAsync = true;
+    }
+
+    /**
+     * @internal
+     */
+    public function hasActiveJob($index = null)
+    {
+        // tick
+        foreach ($this->jobs as &$job) {
+            if ($job['status'] === self::STATUS_STARTED) {
+                if (!$job['process']->isRunning()) {
+                    call_user_func($job['resolve'], $job['process']);
+                }
+            }
+        }
+
+        if (null !== $index) {
+            if ($this->jobs[$index]['status'] === self::STATUS_COMPLETED || $this->jobs[$index]['status'] === self::STATUS_FAILED || $this->jobs[$index]['status'] === self::STATUS_ABORTED) {
+                return false;
+            }
+
+            return true;
+        }
+
+        foreach ($this->jobs as $job) {
+            if (!in_array($job['status'], array(self::STATUS_COMPLETED, self::STATUS_FAILED, self::STATUS_ABORTED), true)) {
+                return true;
+            } else {
+                unset($this->jobs[$job['id']]);
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * @private
+     */
+    public function markJobDone()
+    {
+        $this->runningJobs--;
+
+        foreach ($this->jobs as $job) {
+            if ($job['status'] === self::STATUS_QUEUED) {
+                $this->startJob($job['id']);
+                if ($this->runningJobs >= $this->maxJobs) {
+                    return;
+                }
+            }
+        }
+    }
+
     public function splitLines($output)
     {
         $output = trim($output);

tests/Composer/Test/Downloader/FileDownloaderTest.php

@@ -139,8 +139,8 @@ class FileDownloaderTest extends TestCase
             ->will($this->returnValue($path.'/vendor'));
 
         try {
-            $promise = $downloader->download($packageMock, $path);
             $loop = new Loop($this->httpDownloader);
+            $promise = $downloader->download($packageMock, $path);
             $loop->wait(array($promise));
 
             $this->fail('Download was expected to throw');
@@ -225,8 +225,8 @@ class FileDownloaderTest extends TestCase
         touch($dlFile);
 
         try {
-            $promise = $downloader->download($packageMock, $path);
             $loop = new Loop($this->httpDownloader);
+            $promise = $downloader->download($packageMock, $path);
             $loop->wait(array($promise));
 
             $this->fail('Download was expected to throw');
@@ -296,8 +296,8 @@ class FileDownloaderTest extends TestCase
         mkdir(dirname($dlFile), 0777, true);
         touch($dlFile);
 
-        $promise = $downloader->download($newPackage, $path, $oldPackage);
         $loop = new Loop($this->httpDownloader);
+        $promise = $downloader->download($newPackage, $path, $oldPackage);
         $loop->wait(array($promise));
 
         $downloader->update($oldPackage, $newPackage, $path);

tests/Composer/Test/Downloader/XzDownloaderTest.php

@@ -70,8 +70,8 @@ class XzDownloaderTest extends TestCase
         $downloader = new XzDownloader($io, $config, $httpDownloader = new HttpDownloader($io, $this->getMockBuilder('Composer\Config')->getMock()), null, null, null);
 
         try {
-            $promise = $downloader->download($packageMock, $this->testDir.'/install-path');
             $loop = new Loop($httpDownloader);
+            $promise = $downloader->download($packageMock, $this->testDir.'/install-path');
             $loop->wait(array($promise));
             $downloader->install($packageMock, $this->testDir.'/install-path');
 

tests/Composer/Test/Downloader/ZipDownloaderTest.php

@@ -92,8 +92,8 @@ class ZipDownloaderTest extends TestCase
         $this->setPrivateProperty('hasSystemUnzip', false);
 
         try {
-            $promise = $downloader->download($this->package, $path = sys_get_temp_dir().'/composer-zip-test');
             $loop = new Loop($this->httpDownloader);
+            $promise = $downloader->download($this->package, $path = sys_get_temp_dir().'/composer-zip-test');
             $loop->wait(array($promise));
             $downloader->install($this->package, $path);
 

tests/Composer/Test/Repository/ComposerRepositoryTest.php

@@ -189,16 +189,19 @@ class ComposerRepositoryTest extends TestCase
             ->getMock();
 
         $httpDownloader->expects($this->at(0))
+            ->method('enableAsync');
+
+        $httpDownloader->expects($this->at(1))
             ->method('get')
             ->with($url = 'http://example.org/packages.json')
             ->willReturn(new \Composer\Util\Http\Response(array('url' => $url), 200, array(), json_encode(array('search' => '/search.json?q=%query%&type=%type%'))));
 
-        $httpDownloader->expects($this->at(1))
+        $httpDownloader->expects($this->at(2))
             ->method('get')
             ->with($url = 'http://example.org/search.json?q=foo&type=composer-plugin')
             ->willReturn(new \Composer\Util\Http\Response(array('url' => $url), 200, array(), json_encode($result)));
 
-        $httpDownloader->expects($this->at(2))
+        $httpDownloader->expects($this->at(3))
             ->method('get')
             ->with($url = 'http://example.org/search.json?q=foo&type=library')
             ->willReturn(new \Composer\Util\Http\Response(array('url' => $url), 200, array(), json_encode(array())));
@@ -291,6 +294,9 @@ class ComposerRepositoryTest extends TestCase
             ->getMock();
 
         $httpDownloader->expects($this->at(0))
+            ->method('enableAsync');
+
+        $httpDownloader->expects($this->at(1))
             ->method('get')
             ->with($url = 'http://example.org/packages.json')
             ->willReturn(new \Composer\Util\Http\Response(array('url' => $url), 200, array(), json_encode(array(