add error rendering as JSON

src/ErrorHandler.php

@@ -108,4 +108,124 @@ protected function setExceptionTrace(\Exception $exception, array $trace): void
         $traceReflection->setAccessible(true);
         $traceReflection->setValue($exception, $trace);
     }
+
+    public function shouldRenderErrorAsJson(): bool
+    {
+        return !empty($_SERVER['HTTP_ACCEPT']) && strcasecmp($_SERVER['HTTP_ACCEPT'], 'application/json') === 0;
+    }
+
+    /**
+     * Renders current error information as JSON output.
+     * This method will display information from current {@see getError()} value.
+     *
+     * > Note: this method does NOT terminate the script.
+     */
+    public function renderErrorAsJson(): void
+    {
+        $error = $this->getError();
+        if (empty($error)) {
+            return;
+        }
+
+        unset($error['trace']);
+
+        $responseData = [
+            'error' => $this->getHttpHeader($error['code']),
+            'code' => $error['code'],
+        ];
+
+        $jsonFlags = 0;
+        if (YII_DEBUG) {
+            $jsonFlags = JSON_PRETTY_PRINT;
+
+            $error['traces'] = $this->filterErrorTrace($error['traces']);
+
+            $responseData = array_merge($responseData, $error);
+        }
+
+        header('Content-Type: application/json; charset=utf-8');
+
+        echo json_encode($responseData, $jsonFlags);
+    }
+
+    /**
+     * @param array $trace raw exception stack trace.
+     * @return array simplified stack trace.
+     */
+    private function filterErrorTrace(array $trace): array
+    {
+        /** @var ErrorTraceFilter $traceFilter */
+        $traceFilter = Yii::createComponent([
+            'class' => ErrorTraceFilter::class,
+        ]);
+
+        return $traceFilter->filter($trace);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    protected function renderException(): void
+    {
+        $exception = $this->getException();
+
+        if ($this->errorAction !== null) {
+            Yii::app()->runController($this->errorAction);
+
+            return;
+        }
+
+        if ($exception instanceof \CHttpException || !YII_DEBUG) {
+            $this->renderError();
+
+            return;
+        }
+
+        if ($this->shouldRenderErrorAsJson()) {
+            $this->renderErrorAsJson();
+
+            return;
+        }
+
+        if ($this->isAjaxRequest()) {
+            Yii::app()->displayException($exception);
+
+            return;
+        }
+
+        $this->render('exception', $this->getError());
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    protected function renderError(): void
+    {
+        if ($this->errorAction !== null) {
+            Yii::app()->runController($this->errorAction);
+
+            return;
+        }
+
+        if ($this->shouldRenderErrorAsJson()) {
+            $this->renderErrorAsJson();
+
+            return;
+        }
+
+        $data = $this->getError();
+        if ($this->isAjaxRequest()) {
+            Yii::app()->displayError($data['code'], $data['message'], $data['file'], $data['line']);
+
+            return;
+        }
+
+        if (YII_DEBUG) {
+            $this->render('exception', $data);
+
+            return;
+        }
+
+        $this->render('error',$data);
+    }
 }

src/ErrorTraceFilter.php

@@ -0,0 +1,97 @@
+<?php
+
+namespace yii1tech\error\handler;
+
+use CComponent;
+
+/**
+ * @author Paul Klimov <[email protected]>
+ * @since 1.0
+ */
+class ErrorTraceFilter extends CComponent
+{
+    /**
+     * @var int maximum number of trace source code lines to be displayed. Defaults to 10.
+     */
+    public $maxTraceSourceLines = 10;
+
+    public function filter(array $trace): array
+    {
+        $trace = array_slice($trace, 0, $this->maxTraceSourceLines);
+
+        $result = [];
+        foreach ($trace as $entry) {
+            if (array_key_exists('args', $entry)) {
+                $entry['args'] = $this->simplifyArguments($entry['args']);
+            }
+
+            $result[] = $entry;
+        }
+
+        return $result;
+    }
+
+    /**
+     * Converts arguments array to their simplified representation.
+     *
+     * @param array $args arguments array to be converted.
+     * @return string string representation of the arguments array.
+     */
+    private function simplifyArguments(array $args) : string
+    {
+        $count = 0;
+
+        $isAssoc = $args !== array_values($args);
+
+        foreach ($args as $key => $value) {
+            $count++;
+
+            if ($count >= 5) {
+                if ($count > 5) {
+                    unset($args[$key]);
+                } else {
+                    $args[$key] = '...';
+                }
+
+                continue;
+            }
+
+            $args[$key] = $this->simplifyArgument($value);
+
+            if (is_string($key)) {
+                $args[$key] = "'" . $key . "' => " . $args[$key];
+            } elseif ($isAssoc) {
+                $args[$key] = $key.' => '.$args[$key];
+            }
+        }
+
+        return implode(', ', $args);
+    }
+
+    /**
+     * @param mixed $value
+     * @return mixed
+     */
+    private function simplifyArgument($value)
+    {
+        if (is_object($value)) {
+            return get_class($value);
+        } elseif (is_bool($value)) {
+            return $value ? 'true' : 'false';
+        } elseif (is_string($value)) {
+            if (strlen($value) > 64) {
+                return "'" . substr($value, 0, 64) . "...'";
+            } else {
+                return "'" . $value . "'";
+            }
+        } elseif (is_array($value)) {
+            return '[' . $this->simplifyArguments($value) . ']';
+        } elseif ($value === null) {
+            return 'null';
+        } elseif (is_resource($value)) {
+            return 'resource';
+        }
+
+        return $value;
+    }
+}