Caching and headers

[eluser]Aquillyne[/eluser]
Here's the code changes to the Output class that enable caching of headers.

Wiki entry: Cache headers:

_write_cache function, around line 300 (surrounding code also shown)

Code:

// Implode all the headers into a newline-delimited string
// String is prepended with a pseudo-header giving the expiration time
$headers = "X-CI-Timestamp: " . (time() + ($this->cache_expiration * 60)) . "\n";
$headers .= implode("\n", $this->headers);

flock($fp, LOCK_EX);
fwrite($fp, $headers . "\n\n" . $output); // This line changed
flock($fp, LOCK_UN);
fclose($fp);
@chmod($cache_path, DIR_WRITE_MODE);

_display_cache function, around line 360 (surrounding code also shown)

Code:

// Seperate headers and cache
list($headers, $cache) = explode("\n\n", $cache, 2);
        
// Get each header as an array item
$headers = explode("\n", $headers);
foreach ($headers as $header)
{
    // Is this header the timestamp pseudo-header?
    if (FALSE === strpos($header, "X-CI-Timestamp: "))
    {
        $this->set_header($header); // No, it's not: set the header
    }
    else
    {
        // Has the file expired? If so we'll delete it.
        $timestamp = substr($header, strlen("X-CI-Timestamp: "));
        if (time() >= trim($timestamp))
        {        
            @unlink($filepath);
            log_message('debug', "Cache file has expired. File deleted");
            return FALSE;
        }
    }
}

// Display the cache
$this->_display($cache); // This line changed