Manual File Locking

Table of Contents

Introduction
Example Use Case
Enable or Disable the UI Component
Configuration

Introduction

Manual file locking allows users, if enabled, to lock files in shared areas while working on them in order to prevent concurrent changes from other users (check-in/check-out).

The feature builds on the WebDAV Locks backend which has been introduced with Server 10.1 and is now available in the ownCloud Web Interface. All storages are supported as locking takes place on the WebDAV level. The locks will only be available via ownCloud, not when a user works directly on the storage. Using the context menu of files, every user who has access can lock them. Users can recognize locked files by the means of a new lock indicator. While a file is locked, other users can still access it but they can not make any changes. Locked files can manually be unlocked by the lock owner (the user who locked the file; exclusive locking) using the "Locks" tab in the file details view (right sidebar).

Example Use Case

In a shared folder, one user wants to signal to others that nobody should change a certain file. To do so, the user locks the file. While locked, a copy can be download and locally edited (check-out). When done editing, the user first removes the lock and then uploads the changes (check-in).

Enable or Disable the UI Component

The user-facing components in the web interface are disabled by default because this feature allows users to lock other users' files exclusively. Even the owner of the file can’t unlock them. Lock releasing can only be done by the locking user, a user who is a member of a lock breaking group (if defined), or until the lock expires.

By default, locks set by the user in the web interface will expire after 30 minutes. The maximum lock time by default is 24 hours.

The main user-facing component in the web interface looks like in the following screenshots. If Manual File Locking is disabled, the additional user-facing components are not present:

Manual Locking Disabled

Manual Locking Enabled

If manual locking is enabled, the following additional user-facing components are present:

Administrators can enable Manual File Locking for users either via the web interface or by executing an occ command:

Web interface: Go to Settings Admin General
Using the occ command

sudo -u www-data ./occ config:app:set files enable_lock_file_action --value yes

Configuration

To prevent files being locked infinitely, there is a mechanism that automatically expires locks after a certain time. The expiration time of locks can either be configured via the web interface or using occ commands. In addition, administrators can define groups whose members can break locks.

The default timeout for the locks is, if not specified (in seconds):

Maximum lifetime of a lock set via the web interface (or by not specifying a timeout value when calling the WebDAV Locks API).

The maximum timeout for the locks (in seconds):

Maximum lifetime of locks which is allowed to be set by calling the WebDAV Locks API.

Define lock breaker groups:

Users who are a member of these groups can break locks set by another user.

Web interface

Go to Settings Admin General
The image is the same as shown above when enabling or disabling Manual File Locking.

Using the occ command

Default locks timeout

sudo -u www-data ./occ config:app:set files lock_timeout_default --value 1800

Maximum locks timeout

sudo -u www-data ./occ config:app:set files lock_timeout_max --value 86400

Define lock breaker groups

The example below defines two lock breaker groups named unlockers and admin.
```
sudo -u www-data ./occ config:app:set core lock-breaker-groups --value '["unlockers","admin"]'
```