2. About me
Application Developer
▹ PHP
▹ XSLT/XPath
▹ (some) Javascript
papaya CMS
▹ PHP based Content Management System
▹ uses XSLT for Templates
Thomas Weinert, papaya Software GmbH
3. Steps
Block Send
Check ▹ At Once
▹ Filename ▹ Piece By Piece
▹ File ▹ Limit
Tell
Optimize
▹ Date ▹ Traffic
▹ Size ▹ Performance
▹ Type ▹ Flash
▹ Name
Thomas Weinert, papaya Software GmbH
Problems
4. Block
Move outside document root
.htaccess
▹ Deny From All
Rewrite?
Thomas Weinert, papaya Software GmbH
5. Check Filename
dirname(), basename()
preg_match
strrpos() + substr()
against database
▹ Use hashed random strings for id
▹ Split at chars
▹ virtual directory structure
Thomas Weinert, papaya Software GmbH
6. Check File
file_exists()
▹ return true for directories
is_file()
is_readable()
Thomas Weinert, papaya Software GmbH
7. Check File Type
getimagesize() (no GD needed)
/usr/bin/file
ext/fileinfo (PHP 5.3)
Thomas Weinert, papaya Software GmbH
8. Tell Date
Last change
header('Last-modified: '.
gmdate('D, d M Y H:i:s', $fileDate.' GMT');
Valid until
header('Expires: '.
gmdate('D, d M Y H:i:s', $expireTime).' GMT');
Thomas Weinert, papaya Software GmbH
9. Tell Size
Size
▹ Show progress in browser
header('Content-length: '.$fileSize);
Thomas Weinert, papaya Software GmbH
10. Tell Type
File Mime Type
header('Content-type: '.$mimeType);
Rewrite Filenames
▹ IE check filename
Thomas Weinert, papaya Software GmbH
11. Force Download
IE and Opera
header('Content-type: application/octetstream');
Others
header('Content-type: application/octet-stream');
Thomas Weinert, papaya Software GmbH
12. Tell Filename
For files in browser or IE
header('Content-disposition: inline; filename=quot;'.
$data['file_name'].'quot;');
For downloads - except IE
header('Content-disposition: attachment; filename=quot;'.
$data['file_name'].'quot;');
Escape “ and in filename with
Thomas Weinert, papaya Software GmbH
13. Send – At Once
fpassthru()
readfile()
Pro:
▹ Easy
Contra:
▹ Less control
Thomas Weinert, papaya Software GmbH
14. Send - Piece By Piece
fread()
fseek()
echo, print()
flush()
Thomas Weinert, papaya Software GmbH
15. Send – Piece By Piece
<?php
if ($fh = fopen($localFileName, 'r')) {
while (!feof($fh) &&
connection_status() == 0) {
echo fread($fh, $bytesPerStep);
flush();
}
fclose($fh);
}
?>
Thomas Weinert, papaya Software GmbH
16. Send – Piece By Piece
<?php
if ($fh = fopen($localFileName, 'r')) {
//seek file to start position
if ($fileOffset > 0) {
fseek($fh, $fileOffset);
}
while (!feof($fh) &&
connection_status() == 0) {
echo fread($fh, $bytesPerStep);
flush();
}
fclose($fh);
}
?> Weinert, papaya Software GmbH
Thomas
18. Send – Bandwidth Limit
Track time and send bytes
Sleep some time if sent to fast
▹ usleep(), sleep()
Send first bytes without limit
Why?
▹ Video-Streaming
▹ User don't need all data
Thomas Weinert, papaya Software GmbH
19. if ($shapeRequest) {
$bytesSend += $bytesPerStep;
if ($bytesSend > $shapeLimitStart) {
$timeDiff = microtime(TRUE) - $timeStart;
$rate = ($bytesSend - $shapeLimitStart)
/ $timeDiff;
if ($rate > $shapeLimitRate) {
$sleepFunction($sleepTime);
}
}
}
Thomas Weinert, papaya Software GmbH
20. Optimize - Performance
Close Sessions
▹ session_write_close()
X-Sendfile
▹ header('X-Sendfile: '.$localFileName);
▹ Header for Lighttpd
▹ Apache Extension
Thomas Weinert, papaya Software GmbH
21. Optimize – Flash I
Byte offset tables in video file
▹ ffmpeg ... -g 500 ...
Special player sends GET parameter
▹ JW FLV Player
Server checks GET parameter
▹ PHP script
▹ Lighttpd module
Thomas Weinert, papaya Software GmbH
22. Optimize – Flash – Meta Data
Thomas Weinert, papaya Software GmbH
23. Optimize – Flash II
Check for GET parameters
▹ start, pos, position
Output magic bytes
▹ $flashHeader = 'FLV'.pack('CCNN', 1, 5, 9, 0);
▹ 01 (version) 05 (audio and video)
00 00 00 09 (header size)
00 00 00 00 (size of previous tag)
Seek file
Output file
Thomas Weinert, papaya Software GmbH
24. Problems
will disable flush() / cause buffering
▹ ob_start()
▹ session.use_trans_sid
▹ zlib.output_compression
▹ http:/www.php.net/flush (Comments)
Adobe Acrobat Reader in IE has buggy Range
headers support
Thomas Weinert, papaya Software GmbH
