nextcloud/server · error · Sabre\DAV\Exception

Fail to read part's content.

Error message

Fail to read part's content.

What it means

readPartContent() calls stream_get_line($this->stream, $length) with the part's declared Content-Length; a false return means the underlying read itself failed (distinct from a clean short read, which is caught by the EOF check instead). Thrown as a generic Exception; inside parseNextPart() BulkUploadPlugin catches it, logs it, and answers HTTP 400 with the JSON of files written so far.

Source

Thrown at apps/dav/lib/BulkUpload/MultipartRequestParser.php:218

		return $headers;
	}

	/**
	 * Return the content of a part of the multipart body.
	 *
	 * @throws Exception
	 * @throws BadRequest
	 */
	private function readPartContent(int $length): string {
		if ($length === 0) {
			$content = '';
		} else {
			$content = stream_get_line($this->stream, $length);
		}

		if ($content === false) {
			throw new Exception("Fail to read part's content.");
		}

		if ($length !== 0 && feof($this->stream)) {
			throw new Exception('Unexpected EOF while reading stream.');
		}

		// Read '\r\n'.
		stream_get_contents($this->stream, 2);

		return $content;
	}

	/**
	 * Compute the MD5 or checksum hash of the next x bytes.
	 * TODO: Drop $md5 argument when the latest desktop client that uses it is no longer supported.
	 */
	private function validateHash(int $length, string $fileMd5Header, string $checksumHeader): void {
		if ($checksumHeader !== '') {

View on GitHub (pinned to ecdeb153ff)

Solutions

1. Check nextcloud.log for paired PHP I/O warnings at the same timestamp to identify the stream failure
2. Retry the bulk upload with fewer/smaller files to see whether the failure is size- or load-dependent
3. Fix whatever invalidated the stream resource (premature body close, temp file eviction, memory limit killing the wrapper)

$body = $request->getBody();
if (!is_resource($body) || !is_readable($body)) {
    throw new \RuntimeException('Request body stream is not readable');
}

try {
    [$headers, $content] = $parser->parseNextPart();
} catch (\Exception $e) {
    $this->logger->error($e->getMessage());
    $response->setStatus(400);
    $response->setBody(json_encode($writtenFiles, JSON_THROW_ON_ERROR));
    return false;
}

When it happens

Trigger: A hard read error on the request body stream at the part-content position: invalidated/closed resource, socket error, or stream wrapper failure while slurping the part bytes.

Common situations: Connection torn down mid-body with an RST; temp-file-backed body evicted or deleted under disk pressure; wrapper errors under memory limits.

Related errors

• An error occurred while checking content
• 500
• Boundary not found where it should be.
• An error occurred while reading headers of a part
• 400

AI-assisted analysis of nextcloud/server@ecdeb153ff (2026-08-17). Data as JSON: /api/errors/7d7052d9c6f88853. Report an issue: GitHub.