无法使用PHP创建zip文件

Question

I've created the following code to create a zip file. I'm pulling a list of files from the database depending on the $job_number (which I'm getting from the global $_GET array) and then trying to add them to the zip file.

That part is working fine. It's pulling the list of files from the database, as I can see by echoing or dumping with print_r the results.

The only problem is that the .zip file isn't being created at all. I can't see where I've gone wrong.

$sth = $conn->prepare('SELECT `dp_filename` FROM damage_pics WHERE dp_job_number = :job_number');
$sth->bindParam(':job_number', $job_number);
$sth->setFetchMode(PDO::FETCH_ASSOC);
$sth->execute();

$zip = new ZipArchive();
$zip->open('example5.zip', ZipArchive::CREATE);
$result = $sth->fetchAll();


echo '<pre>';
print_r($result);

foreach ($result as $file)
{
    // just echoing for testing purposes to see if file name is created correctly.
    $image = $file['dp_filename'];
    echo $image . "<br />";
    $zip->addFile("uploads/{$image}");
}

$zip->close();

Answer 1

Sounds like your PHP script is being run with insufficient permissions to write to the destination directory. I did some experimenting, and in such a situation the $zip->open() call would silently fail with no indication of what went wrong.

You could put the following code at the top to determine if this is indeed the problem:

$fp = fopen('example5.zip', 'w');
if ($fp === FALSE) { die("Cannot open example5.zip for writing"); }
fclose($fp);

To fix the issue, I would suggest using an absolute path and filename (such as /tmp/example5.zip) and then make sure that the destination directory is writable by the user that's executing the script (likely whatever user is running the HTTP server software, such as www-data or httpd, depending on the OS and distribution).