Mysqldump is created after headers are sent

Asked Jul 13 '21 at 20:47

Active Jul 13 '21 at 20:47

Viewed 25 times

The issue at hand is that a blank file is downloaded, but the mysqldump file is created in the back end. How do I make the script wait for the dump to be done, and then start the download?

<?php

$filename = 'sqldump_' . date('YmdHis') . '.sql.gz';
$cmd = 'mysqldump --host=localhost --user=blah --password=blah database | gzip -c > ' . $filename;
passthru($cmd);

header('Content-Description: File Transfer');
header('Content-Type: application/x-gzip-compressed');
header("Cache-Control: no-cache, must-revalidate");
header("Expires: 0");
header('Content-Disposition: attachment; filename="' . basename($filename) . '"');
header('Content-Length: ' . filesize($filename));
header('Pragma: public');
header('Content-Disposition: attachment; filename="' . $filename . '"');

exit(0);

asked Jul 13 '21 at 20:47

Alvin Bakker

1,456
21
40

You have to put all the `header()` lines before `passthru()` – Barmar Jul 13 '21 at 20:50
No, mysql is already done. but you need to pass the files content as well _before_ the exit statement. – hakre Jul 13 '21 at 20:51
1

Why use passthru if you're dumping to a file? – Matt Gibson Jul 13 '21 at 20:51
Instead of passthru, use `readfile($filename)` – Barmar Jul 13 '21 at 20:52
@MattGibson: It channels diagnostic messages. – hakre Jul 13 '21 at 20:57
@Barmar I did that also, with the same result – Alvin Bakker Jul 13 '21 at 21:22
Did you put it after all the `header()` lines? – Barmar Jul 13 '21 at 22:46
@Barmar Yes I tried that at first and when that didn't work I switched it – Alvin Bakker Jul 14 '21 at 01:10
I figured it out. Start with all `header()` lines, except `header('Content-Length: ' . filesize($filename));`. Place that line after the passthru and the download knows the file size and correctly downloads it – Alvin Bakker Jul 14 '21 at 18:04

Mysqldump is created after headers are sent

0 Answers0