Add ability to discard events based on class/error names

CHANGELOG.md

@@ -8,6 +8,9 @@ Changelog
 * Out of memory errors will now be reported by increasing the memory limit by 5 MiB. Use the new `memoryLimitIncrease` configuration option to change the amount of memory, or set it to `null` to disable the increase entirely.
   [#621](https://github.com/bugsnag/bugsnag-php/pull/621)
 
+* Add a "discard classes" configuration option that allows events to be discarded based on the exception class name or PHP error name
+  [#622](https://github.com/bugsnag/bugsnag-php/pull/622)
+
 ## 3.25.0 (2020-11-25)
 
 ### Enhancements

src/Client.php

@@ -12,6 +12,7 @@
 use Bugsnag\Internal\GuzzleCompat;
 use Bugsnag\Middleware\BreadcrumbData;
 use Bugsnag\Middleware\CallbackBridge;
+use Bugsnag\Middleware\DiscardClasses;
 use Bugsnag\Middleware\NotificationSkipper;
 use Bugsnag\Middleware\SessionData;
 use Bugsnag\Request\BasicResolver;
@@ -137,6 +138,7 @@ public function __construct(
         $this->sessionTracker = new SessionTracker($config, $this->http);
 
         $this->registerMiddleware(new NotificationSkipper($config));
+        $this->registerMiddleware(new DiscardClasses($config));
         $this->registerMiddleware(new BreadcrumbData($this->recorder));
         $this->registerMiddleware(new SessionData($this));
 
@@ -959,4 +961,30 @@ public function getMemoryLimitIncrease()
     {
         return $this->config->getMemoryLimitIncrease();
     }
+
+    /**
+     * Set the array of classes that should not be sent to Bugsnag.
+     *
+     * @param array $discardClasses
+     *
+     * @return $this
+     */
+    public function setDiscardClasses(array $discardClasses)
+    {
+        $this->config->setDiscardClasses($discardClasses);
+
+        return $this;
+    }
+
+    /**
+     * Get the array of classes that should not be sent to Bugsnag.
+     *
+     * This can contain both fully qualified class names and regular expressions.
+     *
+     * @var array
+     */
+    public function getDiscardClasses()
+    {
+        return $this->config->getDiscardClasses();
+    }
 }

src/Configuration.php

@@ -161,6 +161,15 @@ class Configuration
      */
     protected $memoryLimitIncrease = 5242880;
 
+    /**
+     * An array of classes that should not be sent to Bugsnag.
+     *
+     * This can contain both fully qualified class names and regular expressions.
+     *
+     * @var array
+     */
+    protected $discardClasses = [];
+
     /**
      * Create a new config instance.
      *
@@ -801,4 +810,30 @@ public function getMemoryLimitIncrease()
     {
         return $this->memoryLimitIncrease;
     }
+
+    /**
+     * Set the array of classes that should not be sent to Bugsnag.
+     *
+     * @param array $discardClasses
+     *
+     * @return $this
+     */
+    public function setDiscardClasses(array $discardClasses)
+    {
+        $this->discardClasses = $discardClasses;
+
+        return $this;
+    }
+
+    /**
+     * Get the array of classes that should not be sent to Bugsnag.
+     *
+     * This can contain both fully qualified class names and regular expressions.
+     *
+     * @var array
+     */
+    public function getDiscardClasses()
+    {
+        return $this->discardClasses;
+    }
 }

src/Middleware/DiscardClasses.php

@@ -0,0 +1,50 @@
+<?php
+
+namespace Bugsnag\Middleware;
+
+use Bugsnag\Configuration;
+use Bugsnag\Report;
+
+class DiscardClasses
+{
+    /**
+     * @var \Bugsnag\Configuration
+     */
+    protected $config;
+
+    /**
+     * @param \Bugsnag\Configuration $config
+     */
+    public function __construct(Configuration $config)
+    {
+        $this->config = $config;
+    }
+
+    /**
+     * @param \Bugsnag\Report $report
+     * @param callable        $next
+     *
+     * @return void
+     */
+    public function __invoke(Report $report, callable $next)
+    {
+        $errors = $report->getErrors();
+
+        foreach ($this->config->getDiscardClasses() as $discardClass) {
+            foreach ($errors as $error) {
+                if ($error['errorClass'] === $discardClass
+                    || @preg_match($discardClass, $error['errorClass']) === 1
+                ) {
+                    syslog(LOG_INFO, sprintf(
+                        'Discarding event because error class "%s" matched discardClasses configuration',
+                        $error['errorClass']
+                    ));
+
+                    return;
+                }
+            }
+        }
+
+        $next($report);
+    }
+}

src/Report.php

@@ -644,6 +644,39 @@ public function setSessionData(array $session)
         $this->session = $session;
     }
 
+    /**
+     * Get a list of all errors in a fixed format of:
+     * - 'errorClass'
+     * - 'errorMessage'
+     * - 'type' (always 'php').
+     *
+     * @return array
+     */
+    public function getErrors()
+    {
+        $errors = [$this->toError()];
+        $previous = $this->previous;
+
+        while ($previous) {
+            $errors[] = $previous->toError();
+            $previous = $previous->previous;
+        }
+
+        return $errors;
+    }
+
+    /**
+     * @return array
+     */
+    private function toError()
+    {
+        return [
+            'errorClass' => $this->name,
+            'errorMessage' => $this->message,
+            'type' => 'php',
+        ];
+    }
+
     /**
      * Get the array representation.
      *

tests/ClientTest.php

@@ -10,6 +10,7 @@
 use Exception;
 use GuzzleHttp\Client as Guzzle;
 use GuzzleHttp\Psr7\Uri;
+use LogicException;
 use PHPUnit\Framework\MockObject\MockObject;
 
 /**
@@ -461,6 +462,37 @@ function (Report $report) use (&$pipelineCompleted) {
         $this->assertTrue($pipelineCompleted);
     }
 
+    public function testItAddsDiscardClassesMiddlewareByDefault()
+    {
+        $syslog = $this->getFunctionMock('Bugsnag\Middleware', 'syslog');
+        $syslog->expects($this->once())->with(
+            LOG_INFO,
+            'Discarding event because error class "Exception" matched discardClasses configuration'
+        );
+
+        $client = Client::make('foo');
+        $client->setDiscardClasses([Exception::class]);
+
+        $report = Report::fromPHPThrowable(
+            $client->getConfig(),
+            new Exception('oh no')
+        );
+
+        $pipeline = $client->getPipeline();
+        $pipelineCompleted = false;
+
+        $pipeline->execute(
+            $report,
+            function () use (&$pipelineCompleted) {
+                $pipelineCompleted = true;
+
+                throw new LogicException('This should never be reached!');
+            }
+        );
+
+        $this->assertFalse($pipelineCompleted);
+    }
+
     public function testBreadcrumbsWorks()
     {
         $this->client = new Client($this->config = new Configuration('example-api-key'), null, $this->guzzle);
@@ -1146,6 +1178,25 @@ public function testMemoryLimitIncreaseCanBeSetToNull()
         $this->assertNull($this->client->getMemoryLimitIncrease());
     }
 
+    public function testDiscardClassesDefault()
+    {
+        $this->assertSame([], $this->client->getDiscardClasses());
+    }
+
+    public function testDiscardClassesCanBeSet()
+    {
+        $discardClasses = [
+            \RuntimeException::class,
+            \LogicException::class,
+            \TypeError::class,
+            '/^(Under|Over)flowException$/',
+        ];
+
+        $this->client->setDiscardClasses($discardClasses);
+
+        $this->assertSame($discardClasses, $this->client->getDiscardClasses());
+    }
+
     private function getGuzzleOption($guzzle, $name)
     {
         if (GuzzleCompat::isUsingGuzzle5()) {

tests/ConfigurationTest.php

@@ -325,4 +325,23 @@ public function testMemoryLimitIncreaseCanBeSetToNull()
 
         $this->assertNull($this->config->getMemoryLimitIncrease());
     }
+
+    public function testDiscardClassesDefault()
+    {
+        $this->assertSame([], $this->config->getDiscardClasses());
+    }
+
+    public function testDiscardClassesCanBeSet()
+    {
+        $discardClasses = [
+            \RuntimeException::class,
+            \LogicException::class,
+            \TypeError::class,
+            '/^(Under|Over)flowException$/',
+        ];
+
+        $this->config->setDiscardClasses($discardClasses);
+
+        $this->assertSame($discardClasses, $this->config->getDiscardClasses());
+    }
 }

tests/Fakes/SomeException.php

@@ -0,0 +1,9 @@
+<?php
+
+namespace Bugsnag\Tests\Fakes;
+
+use Exception;
+
+final class SomeException extends Exception
+{
+}