Merge pull request #55 from neighborhoods/leverage-aggressive-error-h…

…andler-for-more-better-forking

Leverage ErrorException to add fork failure context.

src/Process/Forked.php

@@ -15,10 +15,14 @@ abstract class Forked extends ProcessAbstract implements ProcessInterface
     public function start(): ProcessInterface
     {
         $this->_create(self::PROP_HAS_FORKED, true);
-        $processId = $this->_getProcessStrategy()->fork();
-        if ($processId === self::FORK_FAILURE_CODE) {
-            throw (new Exception())->setCode(Exception::CODE_FORK_FAILED);
-        } elseif ($processId > 0) {
+        try {
+            $processId = $this->_getProcessStrategy()->fork();
+        } /** @noinspection PhpRedundantCatchClauseInspection */
+        catch (\ErrorException $errorException) {
+            throw (new Exception())->setCode(Exception::CODE_FORK_FAILED)->setPrevious($errorException);
+        }
+
+        if ($processId > 0) {
             // This is executed in the parent process.
             $this->_setProcessId($processId);
         } else {

src/Process/Pool/Strategy.yml

@@ -16,8 +16,6 @@ services:
     shared: false
     class: Neighborhoods\Kojo\Process\Pool\Strategy\Server
     calls:
-      - [setAlarmProcessTypeCode, ['root']]
-      - [setFillProcessTypeCode, ['root']]
       - [setLogger, ['@process.pool.logger']]
       - [setMaximumLoadAverage, ['%process.pool.strategy-server.maximum_load_average%']]
   process.pool.strategy-server:

src/Process/Pool/Strategy/Server.php

@@ -49,6 +49,7 @@ public function initializePool(): StrategyInterface
                 $this->_getProcessPool()->addChildProcess($process);
             } catch (Exception $forkedException) {
                 $this->_getLogger()->critical($forkedException->getMessage(), [(string)$forkedException]);
+                $this->_getProcessPool()->getProcess()->exit();
             }
         }
         if ($this->_hasFillProcessTypeCode() && $this->_getProcessPool()->canEnvironmentSustainAdditionProcesses()) {

src/Process/Strategy/ProcessControl.php

@@ -11,4 +11,4 @@ public function fork(): int
     {
         return pcntl_fork();
     }
-}
+}

src/ProcessAbstract.php

@@ -98,6 +98,7 @@ public function exit(): void
     {
         $this->unregisterShutdownMethod();
         $this->_getProcessPool()->terminateChildProcesses();
+        $this->_getLogger()->debug("Exiting.");
         exit($this->_exitCode);
     }
 

src/Runtime/ExceptionInterface.php

@@ -10,4 +10,8 @@ public function setCode(string $code): ExceptionInterface;
     public function addMessage(string $additionalMessage): ExceptionInterface;
 
     public function jsonSerialize();
+
+    public function setPrevious(\Throwable $previous): ExceptionInterface;
+
+    public function addPossibleMessage(string $code, string $message): ExceptionInterface;
 }