Zip directory or file

zip_dir.php

<?php
ini_set('max_execution_time', 600);
ini_set('memory_limit', '1024M');

// -------------------------------
$source = __DIR__ . '/images';
$dest = __DIR__ . '/images.zip';
// -------------------------------

printf("Start zip '%s' %s to '%s'\n%s", $source, is_dir($source) ? 'directory' : 'file', $dest, zipDirOrFile($source, $dest));

function zipDirOrFile($source, $dest)
{
    $zip = new ZipArchive();
    if (($result = $zip->open($dest, ZIPARCHIVE::CREATE)) === true) {
        $source = realpath($source);

        if (is_dir($source)) {
            $iterator = new RecursiveDirectoryIterator($source);
            $iterator->setFlags(FilesystemIterator::SKIP_DOTS);
            $files = new RecursiveIteratorIterator($iterator, RecursiveIteratorIterator::SELF_FIRST);

            foreach ($files as $file) {
                $file = realpath($file);
                if (is_dir($file)) {
                    $zip->addEmptyDir(str_replace($source . DIRECTORY_SEPARATOR, '', $file . DIRECTORY_SEPARATOR));
                } elseif (is_file($file)) {
                    $zip->addFile($file, str_replace($source . DIRECTORY_SEPARATOR, '', $file));
                }
            }

        } elseif (is_file($source)) {
            $zip->addFile($source, basename($source));
        }

        return $zip->close() ? 'Success' : 'Failure zip operation';
    }

    return 'Failed with error: ' . getZipErrorMessage($result);
}

function getZipErrorMessage($result)
{
    switch ($result) {
        case ZipArchive::ER_EXISTS:
            $ErrMsg = 'File already exists';
            break;
        case ZipArchive::ER_INCONS:
            $ErrMsg = 'Zip archive inconsistent';
            break;
        case ZipArchive::ER_MEMORY:
            $ErrMsg = 'Malloc failure';
            break;
        case ZipArchive::ER_NOENT:
            $ErrMsg = 'No such file';
            break;
        case ZipArchive::ER_NOZIP:
            $ErrMsg = 'Not a zip archive';
            break;
        case ZipArchive::ER_OPEN:
            $ErrMsg = 'Can\'t open file';
            break;
        case ZipArchive::ER_READ:
            $ErrMsg = 'Read error';
            break;
        case ZipArchive::ER_SEEK:
            $ErrMsg = 'Seek error';
            break;
        default:
            $ErrMsg = 'Unknown error';
            break;
    }

    return $ErrMsg;
}