Add a formatter to compactly print stack traces

composer.json

@@ -9,7 +9,7 @@
     ],
     "homepage": "https://github.com/zendframework/zend-log",
     "require": {
-        "php": "^5.6 || ^7.0",
+        "php": "^7.0",
         "psr/log": "^1.0",
         "zendframework/zend-servicemanager": "^2.7.5 || ^3.0.3",
         "zendframework/zend-stdlib": "^2.7 || ^3.0"

src/Formatter/NativeException.php

@@ -0,0 +1,164 @@
+<?php
+/**
+ * Zend Framework (http://framework.zend.com/)
+ *
+ * @link      http://github.com/zendframework/zend-log for the canonical source repository
+ * @copyright Copyright (c) 2005-2016 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license   http://framework.zend.com/license/new-bsd New BSD License
+ */
+
+namespace Zend\Log\Formatter;
+
+// @codingStandardsIgnoreStart
+/**
+ * Format an Exception in a similar way PHP does by default when an exception bubbles to the top
+ *
+ * This is a snippet of the native PHP format which it resembles
+ *
+ * [Wed Oct 11 15:45:18 2017] PHP Fatal error:  Uncaught RuntimeException: error message in /module/MyModule/src/Module.php:11
+ * Stack trace:
+ * #0 /vendor/zendframework/zend-modulemanager/src/Listener/ConfigListener.php(124): MyModule\Module->getConfig()
+ * #1 [internal function]: Zend\ModuleManager\Listener\ConfigListener->onLoadModule(Object(Zend\ModuleManager\ModuleEvent))
+ * #2 /vendor/zendframework/zend-eventmanager/src/EventManager.php(490): call_user_func(Array, Object(Zend\ModuleManager\ModuleEvent))
+ * #3 /vendor/zendframework/zend-eventmanager/src/EventManager.php(251): Zend\EventManager\EventManager->triggerListeners('loadModule', Object(Zend\ModuleManager\ModuleEvent))
+ * #4 /vendor/zendframework/zend-modulemanager/src/ModuleManager.php(181): Zend\EventManager\EventManager->triggerEvent(Object(Zend\ModuleManager\ModuleEvent))
+ */
+// @codingStandardsIgnoreEnd
+class NativeException implements FormatterInterface
+{
+    /**
+     * Format specifier for DateTime objects in event data
+     *
+     * @see http://php.net/manual/en/function.date.php
+     * @var string
+     */
+    protected $dateTimeFormat = self::DEFAULT_DATETIME_FORMAT;
+
+    /**
+     * Transform an event created from a PHP exception to a log entry in human-readable format
+     *
+     * @param mixed[] $event
+     * @return string
+     */
+    public function format($event): string
+    {
+        if ($event['timestamp'] instanceof \DateTimeInterface) {
+            $event['timestamp'] = $event['timestamp']->format($this->getDateTimeFormat());
+        }
+
+        $output = '[' . $event['timestamp'] . '] ' . $event['priorityName'] . ' ('
+            . $event['priority'] . ') ' . $event['message'] .' in '
+            . $event['extra']['file'] . ':' . $event['extra']['line']
+            . "\n";
+
+        if (! empty($event['extra']['trace'])) {
+            $output .= "Stack trace:\n";
+            foreach ($event['extra']['trace'] as $i => $traceLine) {
+                $output .= "#$i " . $this->formatTraceLine($traceLine) . "\n";
+            }
+        }
+
+        return trim($output);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function getDateTimeFormat(): string
+    {
+        return $this->dateTimeFormat;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function setDateTimeFormat($dateTimeFormat)
+    {
+        $this->dateTimeFormat = (string) $dateTimeFormat;
+        return $this;
+    }
+
+    /**
+     * Transform an element of the array Exception::getTrace
+     * to a string of a single line
+     *
+     * @param mixed[] $trace element of Exception::getTrace
+     * @return string of a single line
+     */
+    private function formatTraceLine(array $trace): string
+    {
+        $arguments = $this->formatArguments($trace['args']);
+        $output = '';
+
+        if (isset($trace['file'])) {
+            $output .= $trace['file'];
+
+            if (isset($trace['line'])) {
+                $output .= '(' . $trace['line'] . ')';
+            }
+
+            $output .= ': ';
+        }
+
+        $output .= $trace['class'] ?? '';
+        $output .= $trace['type'] ?? '';
+        $output .= $trace['function'] ?? '';
+
+        $arguments = $this->formatArguments($trace['args'] ?? []);
+        $output .= '(' . $arguments . ')';
+
+        return $output;
+    }
+
+    /**
+     * Convert function arguments of any type to a short readable string
+     *
+     * @param mixed[] $arguments
+     * @return string a summary of the list of arguments
+     */
+    private function formatArguments(array $arguments): string
+    {
+        return implode(', ', array_map([$this, 'formatArgument'], $arguments));
+    }
+
+    /**
+     * Summarize a variable
+     *
+     * @param mixed $argument anything at all
+     * @return string a summary of the argument
+     */
+    private function formatArgument($argument): string
+    {
+        if (is_int($argument) || is_float($argument)) {
+            return $argument;
+        }
+
+        if (is_string($argument)) {
+            if (strlen($argument) < 80) {
+                $truncated = $argument;
+            } else {
+                $truncated = substr($argument, 0, 30) . '...' . substr($argument, -30, 30);
+            }
+
+            return "'$truncated'";
+        }
+
+        if ($argument === false) {
+            return 'false';
+        }
+
+        if ($argument === true) {
+            return 'true';
+        }
+
+        if (is_array($argument)) {
+            return 'Array(' . count($argument) . ')';
+        }
+
+        if (is_object($argument)) {
+            return 'Object(' . get_class($argument) . ')';
+        }
+
+        return gettype($argument);
+    }
+}

test/Formatter/NativeExceptionTest.php

@@ -0,0 +1,63 @@
+<?php
+/**
+ * Zend Framework (http://framework.zend.com/)
+ *
+ * @link      http://github.com/zendframework/zf2 for the canonical source repository
+ * @copyright Copyright (c) 2005-2015 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license   http://framework.zend.com/license/new-bsd New BSD License
+ */
+
+namespace ZendTest\Log\Formatter;
+
+use DateTime;
+use PHPUnit\Framework\TestCase;
+use Zend\Log\Formatter\NativeException;
+
+class NativeExceptionTest extends TestCase
+{
+    public function testFormat()
+    {
+        $date = new DateTime('2017-10-11T22:12:13+02:00');
+
+        $event = [
+            'timestamp'    => $date,
+            'message'      => 'testmessage',
+            'priority'     => 3,
+            'priorityName' => 'ERR',
+            'extra' => [
+                'file'  => 'test.php',
+                'line'  => 12,
+                'trace' => [
+                    [
+                        'file'     => 'test.php',
+                        'line'     => 12,
+                        'function' => 'topTestMethod',
+                        'class'    => 'Test',
+                        'type'     => '::',
+                        'args'     => [1]
+                    ],
+                    [
+                        'file'     => 'test.php',
+                        'line'     => 5,
+                        'function' => 'mainTestMethod',
+                        'class'    => 'Test',
+                        'type'     => '::',
+                        'args'     => [2]
+                    ]
+                ]
+            ]
+        ];
+
+        $expected = trim("
+[2017-10-11T22:12:13+02:00] ERR (3) testmessage in test.php:12
+Stack trace:
+#0 test.php(12): Test::topTestMethod(1)
+#1 test.php(5): Test::mainTestMethod(2)
+        ");
+
+        $formatter = new NativeException();
+        $output = $formatter->format($event);
+
+        $this->assertEquals($expected, $output);
+    }
+}