git.m6w6.name Git - mdref/mdref/blob - mdref/ExceptionHandler.php

   1 <?php
   2
   3 namespace mdref;
   4
   5 use http\Env;
   6 use function debug_print_backtrace;
   7 use function error_get_last;
   8 use function headers_sent;
   9 use function implode;
  10 use function ob_end_clean;
  11 use function ob_get_clean;
  12 use function ob_get_level;
  13 use function ob_start;
  14 use function register_shutdown_function;
  15 use function set_error_handler;
  16 use function set_exception_handler;
  17 use function sprintf;
  18 use const E_COMPILE_ERROR;
  19 use const E_CORE_ERROR;
  20 use const E_ERROR;
  21 use const E_PARSE;
  22 use const E_USER_ERROR;
  23
  24 /**
  25  * Exception and error handler
  26  */
  27 class ExceptionHandler
  28 {
  29         /**
  30          * @var \http\Env\Response
  31          */
  32         private $response;
  33
  34         /**
  35          * Set up error/exception/shutdown handler
  36          * @param Env\Response $r
  37          */
  38         public function __construct(Env\Response $r) {
  39                 $this->response = $r;
  40                 set_exception_handler($this);
  41                 set_error_handler($this);
  42                 register_shutdown_function($this);
  43         }
  44
  45         /**
  46          * Clean output buffers
  47          */
  48         private static function cleanBuffers() : void {
  49                 while (ob_get_level()) {
  50                         if (!@ob_end_clean()) {
  51                                 break;
  52                         }
  53                 }
  54         }
  55
  56         /**
  57          * The exception/error/shutdown handler callback
  58          *
  59          * @param \Throwable|string $e
  60          * @param ?string $msg
  61          * @throws \Exception
  62          */
  63         public function __invoke($e = null, ?string $msg = null) : void {
  64                 if ($e instanceof \Throwable) {
  65                         try {
  66                                 self::cleanBuffers();
  67                                 echo static::htmlException($e);
  68                         } catch (\Exception $ignore) {
  69                                 headers_sent() or Env::setResponseCode(500);
  70                                 die("FATAL ERROR:\n$e\n$ignore");
  71                         }
  72                 } elseif (isset($e, $msg)) {
  73                         throw new \Exception($msg, $e);
  74                 } elseif (($error = error_get_last())) {
  75                         switch ($error["type"]) {
  76                         case E_PARSE:
  77                         case E_ERROR:
  78                         case E_USER_ERROR:
  79                         case E_CORE_ERROR:
  80                         case E_COMPILE_ERROR:
  81                                 self::cleanBuffers();
  82                                 $message = sprintf("%s in %s at line %d",
  83                                         $error["message"], $error["file"], $error["line"]);
  84                                 echo static::htmlError("Application Error", $message, 500, "");
  85                                 break;
  86                         }
  87                 }
  88         }
  89
  90         /**
  91          * Format an exception as HTML and send appropriate exception info as HTTP headers
  92          * @param \Throwable $e
  93          * @param array $title_tag
  94          * @param array $message_tag
  95          * @param array $trace_tag
  96          * @return string
  97          */
  98         public static function htmlException(\Throwable $e, array $title_tag = ["h1"], array $message_tag = ["p"],
  99                         array $trace_tag = ["pre", "style='font-size:smaller;overflow-x:scroll'"]) : string {
 100                 if ($e instanceof Exception) {
 101                         $code = $e->getCode() ?: 500;
 102                 } else {
 103                         $code = 500;
 104                 }
 105
 106                 for ($html = ""; $e; $e = $e->getPrevious()) {
 107                         $html .= static::htmlError(Env::getResponseStatusForCode($code),
 108                                 $e->getMessage(), $code, $e->getTraceAsString(),
 109                                 $title_tag, $message_tag, $trace_tag);
 110                 }
 111                 return $html;
 112         }
 113
 114         /**
 115          * Format an error as HTML
 116          * @param string $title
 117          * @param string $message
 118          * @param int $code
 119          * @param string $trace
 120          * @param array $title_tag
 121          * @param array $message_tag
 122          * @param array $trace_tag
 123          * @return string
 124          */
 125         public static function htmlError($title, $message, $code, $trace = null, array $title_tag = ["h1"],
 126                         array $message_tag = ["p"], array $trace_tag = ["pre", "style='font-size:smaller;overflow-x:scroll'"]) : string {
 127                 Env::setResponseCode($code);
 128
 129                 $html = sprintf("<%s>%s</%s>\n<%s>%s</%s>\n",
 130                                 implode(" ", $title_tag), $title, $title_tag[0],
 131                                 implode(" ", $message_tag), $message, $message_tag[0]);
 132                 if ($trace_tag) {
 133                         if (!isset($trace)) {
 134                                 ob_start();
 135                                 debug_print_backtrace();
 136                                 $trace = ob_get_clean();
 137                         }
 138                         if (!empty($trace)) {
 139                                 $html .= sprintf("<%s>%s</%s>\n",
 140                                                 implode(" ", $trace_tag), $trace, $trace_tag[0]);
 141                         }
 142                 }
 143
 144                 return $html;
 145         }
 146 }