php解析日志文件获取空输出没有错误

Question

我是php的新手。我试图解析日志文件并期待数组输出。但不幸的是输出是空的，没有错误/警告。

我试着按照这个例子，在这里：http://www.phpclasses.org/package/2596-PHP-Parse-Apache-log-files-in-the-common-log-format.html

以下是代码：

Apache的日志parser.php

<?php
class apache_log_parser
{

  var $bad_rows; // Number of bad rows
  var $fp; // File pointer

  function format_log_line($line)
  {
    preg_match("/^(\S+) (\S+) (\S+) \[([^:]+):(\d+:\d+:\d+) ([^\]]+)\] \"(\S+) (.*?) (\S+)\" (\S+) (\S+) (\".*?\") (\".*?\")$/", $line, $matches); // pattern to format the line
    return $matches;
  }

  function format_line($line)
  {
    $logs = $this->format_log_line($line); // format the line


    if (isset($logs[0])) // check that it formated OK
    {
      $formated_log = array(); // make an array to store the lin info in
      $formated_log['ip'] = $logs[1];
      $formated_log['identity'] = $logs[2];
      $formated_log['user'] = $logs[2];
      $formated_log['date'] = $logs[4];
      $formated_log['time'] = $logs[5];
      $formated_log['timezone'] = $logs[6];
      $formated_log['method'] = $logs[7];
      $formated_log['path'] = $logs[8];
      $formated_log['protocal'] = $logs[9];
      $formated_log['status'] = $logs[10];
      $formated_log['bytes'] = $logs[11];
      $formated_log['referer'] = $logs[12];
      $formated_log['agent'] = $logs[13];
      return $formated_log; // return the array of info
    }
    else
    {
      $this->bad_rows++; // if the row is not in the right format add it to the bad rows
      return false;
    }
  }

  function open_log_file($file_name)
  {
    $this->fp = fopen($file_name, 'r'); // open the file
    if (!$this->fp)
    {
      return false; // return false on fail
    }
    return true; // return true on sucsess
  }

  function close_log_file()
  {
    return fclose($this->fp); // close the file
  }

  // gets a line from the log file
  function get_line()
  {
    if (feof($this->fp))
    {
       return false;
    }
    $bits='';
    // I find for loops much much faster
    for (;!feof($this->fp) && $bits != "\n";)
    {
      $bits .= fread($this->fp, 1);
    }
    return rtrim($bits, "\n");
  }

}
?>

使用example.php

<?php
include 'apache-log-parser.php';

$apache_log_parser = new apache_log_parser(); // Create an apache log parser

if ($apache_log_parser->open_log_file('example.log')) // Make sure it opens the log file
{
  while ($line = $apache_log_parser->get_line()) { // while it can get a line
//print_r($line);
    $parsed_line = $apache_log_parser->format_line($line); // format the line
    //var_export($parsed_line);
   // print_r($parsed_line); // print out the array
  }
  $apache_log_parser->close_log_file(); // close the log file
}
else
{
  echo 'Sorry cannot open log file.';
}
?>

example.log

172.0.0.1 - - [21/Sep/2005:23:06:37 +0100] "GET / HTTP/1.1" 404 - "-" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8b3) Gecko/20050712 Firefox/1.0+"
172.0.0.1 - - [21/Sep/2005:23:06:38 +0100] "GET / HTTP/1.1" 200 1647 "http://www.example.com/" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8b3) Gecko/20050712 Firefox/1.0+"
172.0.0.1 - - [21/Sep/2005:23:06:38 +0100] "GET / HTTP/1.1" 404 - "-" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8b3) Gecko/20050712 Firefox/1.0+"
172.0.0.1 - - [21/Sep/2005:23:06:38 +0100] "GET / HTTP/1.1" 404 - "-" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8b3) Gecko/20050712 Firefox/1.0+"
172.0.0.1 - - [21/Sep/2005:23:06:39 +0100] "GET / HTTP/1.1" 404 - "-" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8b3) Gecko/20050712 Firefox/1.0+"
172.0.0.1 - - [21/Sep/2005:23:06:40 +0100] "GET / HTTP/1.1" 200 12372 "http://www.example.com/" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8b3) Gecko/20050712 Firefox/1.0+"
172.0.0.1 - - [21/Sep/2005:23:06:40 +0100] "GET / HTTP/1.1" 404 - "-" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8b3) Gecko/20050712 Firefox/1.0+"
172.0.0.1 - - [21/Sep/2005:23:06:41 +0100] "GET / HTTP/1.1" 404 - "-" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8b3) Gecko/20050712 Firefox/1.0+"
172.0.0.1 - - [21/Sep/2005:23:06:41 +0100] "GET / HTTP/1.1" 404 - "-" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8b3) Gecko/20050712 Firefox/1.0+"

如果有人对此进行调查并建议我做出哪些改变，我将很高兴。