ILockAsync Interface

This interface provides the means for locking the hierarchy item, updating lock timeout and accessing the list of applied locks. To create WebDAV Class 2 compliant server you must implement this interface on your file and folder items.

When this interface is implemented on an item the server reports Class 2 compliance, returning DAV: 1, 2, 3 header in response to the OPTIONS request. Note that while most WebDAV clients never lock folder items, you must still add this interface on folders, as soon as WebDAV clients submit OPTIONS request against folder items when discovering server compliance.

When a WebDAV client requires to protect an item from concurrent updates, it locks the item (usually file), submitting lock request to server. The server generates the new lock-token, marks the item as locked and returns the new lock-token to the client. The WebDAV client application keeps the lock-token and when it requires to perform any updates, it supplies the lock-token with the request. When the server receives the update request, it verifies that the lock token belongs to the item that is being updated and performs modifications.

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