BookStackApp/BookStack · error · ZipImportException

File $fileName exceeds app upload limit.

Error message

File $fileName exceeds app upload limit.

What it means

ZipImportRunner::zipFileToUploadedFile() converts an embedded ZIP member into a simulated UploadedFile. Before extracting it calls ZipExportReader::fileWithinSizeLimit($fileName); if the member (image/attachment) exceeds the app.upload_limit it throws ZipImportException 'File $fileName exceeds app upload limit.' This aborts the import of that book/attachment/image.

Source

Thrown at app/Exports/ZipExports/ZipImportRunner.php:260

        return $image;
    }

    protected function exportTagsToInputArray(array $exportTags): array
    {
        $tags = [];

        /** @var ZipExportTag $tag */
        foreach ($exportTags as $tag) {
            $tags[] = ['name' => $tag->name, 'value' => $tag->value ?? ''];
        }

        return $tags;
    }

    protected function zipFileToUploadedFile(string $fileName, ZipExportReader $reader, bool $forceExtensionFromMime = false): UploadedFile
    {
        if (!$reader->fileWithinSizeLimit($fileName)) {
            throw new ZipImportException([
                "File $fileName exceeds app upload limit."
            ]);
        }

        $tempPath = tempnam(sys_get_temp_dir(), 'bszipextract');
        $fileStream = $reader->streamFile($fileName);
        $tempStream = fopen($tempPath, 'wb');
        stream_copy_to_stream($fileStream, $tempStream);
        fclose($tempStream);

        $this->tempFilesToCleanup[] = $tempPath;

        $intendedUploadName = $fileName;
        if ($forceExtensionFromMime) {
            $mime = $reader->sniffFileMime($fileName);
            $extension = explode('/', $mime)[1];
            if (!str_ends_with(strtolower($intendedUploadName), '.' . $extension)) {
                $intendedUploadName .= '.' . $extension;

View on GitHub (pinned to 18f8469a1c)

Solutions

1. Increase APP_UPLOAD_LIMIT (config/app.php 'upload_limit') on the importing instance and run php artisan config:clear.
2. Remove or shrink the offending file(s) from the source instance and re-export.
3. Identify the file from the message ($fileName) and check its size with `unzip -l export.zip`.
4. Import without the large attachment and add it manually afterward.

Example fix

// before (.env on target)
APP_UPLOAD_LIMIT=5
// after
APP_UPLOAD_LIMIT=100

$zip = new ZipArchive();
$zip->open($path);
$limit = max((int) config('app.upload_limit'), 1) * 1000000;
for ($i = 0; $i < $zip->numFiles; $i++) {
    $stat = $zip->statIndex($i);
    if ($stat['size'] > $limit) {
        throw new \RuntimeException("{$stat['name']} exceeds upload limit");
    }
}

try {
    $runner->run($import, $parent);
} catch (\BookStack\Exceptions\ZipImportException $e) {
    // message names the oversized file; raise limit or shrink it
}

When it happens

Trigger: ZIP export contains an image or attachment whose uncompressed size exceeds config('app.upload_limit') MB during importBook/importAttachment/importImage.

Common situations: Large media files exported from a source instance with a higher limit, imported into a target instance with a lower limit; default upload_limit on new installs; shared hosting constraints.

Understand the failure class

Background: "File too large" / "file size exceeds limit" errors: why libraries cap file sizes and how to fix them — this error's family across 46 libraries.

Related errors

• errors.import_zip_data_too_large
• errors.import_zip_cant_decode_data
• Could not identify content in ZIP file data.
• errors.import_validation_failed
• Must not have a parent set for a Book import.

AI-assisted analysis of BookStackApp/BookStack@18f8469a1c (2026-09-02). Data as JSON: /api/errors/a2b3f2dc00f79f0e. Report an issue: GitHub.