PHP使用sed或preg_replace从日志中删除特殊字符

Question

I'm using this AJAX Logfile Tailer & Viewer: http://commavee.com/2007/04/13/ajax-logfile-tailer-viewer/ It works well but on the page where the log is being displayed it isn't filtering any special characters so it looks messy. I'm trying to modify the logtail.php file to clean out the special characters but can't quite get it working.

Here is the original logtail.php file:

<?
// logtail.php
$cmd = "tail -50 /home/user/logfile.log";
exec("$cmd 2>&1", $output);
foreach($output as $outputline) {
 echo ("$outputline\n");
}
?>

Here is my modified logtail.php file in which I am attempting to clean out the special characters from:

<?php
ini_set('display_errors', 1);
ini_set('error_reporting', E_ALL);

$cmd = "tail -50 /home/user/logfile.log";
exec("$cmd 2>&1", $output);

foreach($output as $outputline) {
 exec('sed -r '.escapeshellarg("s/\x1B\[([0-9]{1,2}(;[0-9]{1,2})?)?[m|K]//g").' $output');
 echo ("$outputline\n");


}
?>

Update: I think this should take the original output, clean out the special characters, and then output the cleaned up text, but it doesn't work as I still see junk like this:

[0;35;1m[something] text here[m

The [something] part is fine but the [0;35;1m ... [m needs to go.

Answer 1

You outputting the source line instead of resulting.

Your code could be like that:

foreach($output as $outputline) {
 exec("echo \"$output\" | sed -r ".escapeshellarg("s/\x1B\[([0-9]{1,2}(;[0-9]{1,2})?)?[m|K]//g"), $output);
 echo ("$outputline\n");
}

But this will be not efficient.

Better is to use preg_replace function like that:

<?php
// logtail.php
$cmd = "tail -50 /home/user/logfile.log";
exec("$cmd 2>&1", $output);

$str = implode('\n', $output);
$result = preg_replace('/\x1B\[([0-9]{1,2}(;[0-9]{1,2})?)?[m|K]/', '', $str);

echo ("$result\n");
?>