Add ability to set Environment class name

bin/worker

@@ -40,10 +40,36 @@ ob_start(function ($data) {
 
 Amp\Loop::run(function () {
     $channel = new Sync\ChannelledSocket(STDIN, STDOUT);
-    $environment = new Worker\BasicEnvironment;
-    $runner = new Worker\TaskRunner($channel, $environment);
 
     try {
+        $environment = (function (): Worker\Environment {
+            $options = getopt("e:");
+
+            if (!isset($options["e"])) {
+                throw new Error("No environment class name provided");
+            }
+
+            $className = $options["e"];
+
+            try {
+                $reflection = new ReflectionClass($className);
+            } catch (ReflectionException $e) {
+                throw new Error(sprintf("Invalid class name '%s'", $className));
+            }
+
+            if (!$reflection->isInstantiable()) {
+                throw new Error(sprintf("'%s' is not instatiable class", $className));
+            }
+
+            if (!$reflection->implementsInterface(Worker\Environment::class)) {
+                throw new Error(sprintf("The class '%s' does not implement '%s'", $className,Worker\Environment::class));
+            }
+
+            return $reflection->newInstance();
+        })();
+
+        $runner = new Worker\TaskRunner($channel, $environment);
+
         $result = new Sync\Internal\ExitSuccess(yield $runner->run());
     } catch (Sync\ChannelException $exception) {
         exit(1); // Parent context died, simply exit.

lib/Process/ChannelledProcess.php

@@ -25,20 +25,27 @@ class ChannelledProcess implements ProcessContext, Strand {
     private $channel;
 
     /**
-     * @param string  $path Path to PHP script.
+     * @param string|array $script Path to PHP script or array with first element as path and following elements options
+     *     to the PHP script (e.g.: ['bin/worker', '-eOptionValue', '-nOptionValue'].
      * @param string $cwd Working directory.
      * @param mixed[] $env Array of environment variables.
      */
-    public function __construct(string $path, string $cwd = "", array $env = []) {
+    public function __construct($script, string $cwd = "", array $env = []) {
         $options = [
             "html_errors" => "0",
             "display_errors" => "0",
             "log_errors" => "1",
         ];
 
+        if (\is_array($script)) {
+            $script = \implode(" ", \array_map("escapeshellarg", $script));
+        } else {
+            $script = \escapeshellarg($script);
+        }
+
         $options = (\PHP_SAPI === "phpdbg" ? " -b -qrr " : " ") . $this->formatOptions($options);
         $separator = \PHP_SAPI === "phpdbg" ? " -- " : " ";
-        $command = \escapeshellarg(\PHP_BINARY) . $options . $separator . \escapeshellarg($path);
+        $command = \escapeshellarg(\PHP_BINARY) . $options . $separator . $script;
 
         $processOptions = [];
 

lib/Worker/WorkerProcess.php

@@ -8,8 +8,18 @@ use Amp\Parallel\Process\ChannelledProcess;
  * A worker thread that executes task objects.
  */
 class WorkerProcess extends AbstractWorker {
-    public function __construct() {
+    /**
+     * @param string $envClassName Name of class implementing \Amp\Parallel\Worker\Environment to instigate.
+     *     Defaults to \Amp\Parallel\Worker\BasicEnvironment.
+     * @param mixed[] $env Array of environment variables to pass to the worker. Empty array inherits from the current
+     *     PHP process. See the $env parameter of \Amp\Process\Process::__construct().
+     */
+    public function __construct(string $envClassName = BasicEnvironment::class, array $env = []) {
         $dir = \dirname(__DIR__, 2) . '/bin';
-        parent::__construct(new ChannelledProcess($dir . '/worker', $dir));
+        $script = [
+            $dir . "/worker",
+            "-e" . $envClassName,
+        ];
+        parent::__construct(new ChannelledProcess($script, $dir, $env));
     }
 }

lib/Worker/WorkerThread.php

@@ -9,10 +9,34 @@ use Amp\Promise;
  * A worker thread that executes task objects.
  */
 class WorkerThread extends AbstractWorker {
-    public function __construct() {
-        parent::__construct(new Thread(function (): Promise {
-            $runner = new TaskRunner($this, new BasicEnvironment);
+    /**
+     * @param string $envClassName Name of class implementing \Amp\Parallel\Worker\Environment to instigate.
+     *     Defaults to \Amp\Parallel\Worker\BasicEnvironment.
+     */
+    public function __construct(string $envClassName = BasicEnvironment::class) {
+        parent::__construct(new Thread(function (string $className): Promise {
+            try {
+                $reflection = new \ReflectionClass($className);
+            } catch (\ReflectionException $e) {
+                throw new \Error(\sprintf("Invalid class name '%s'", $className));
+            }
+
+            if (!$reflection->isInstantiable()) {
+                throw new \Error(\sprintf("'%s' is not instatiable class", $className));
+            }
+
+            if (!$reflection->implementsInterface(Environment::class)) {
+                throw new \Error(\sprintf("The class '%s' does not implement '%s'", $className, Environment::class));
+            }
+
+            $environment = $reflection->newInstance();
+
+            if (!\defined("AMP_WORKER")) {
+                \define("AMP_WORKER", "amp-worker");
+            }
+
+            $runner = new TaskRunner($this, $environment);
             return $runner->run();
-        }));
+        }, $envClassName));
     }
 }