dav_ext_lock
The 'dav_ext_lock' directive enables WebDAV locking capabilities within the specified context in NGINX.
Description
The 'dav_ext_lock' directive is part of the NGINX WebDAV extension module that allows users to enable locking functionality on resources accessed through WebDAV. By using this directive, administrators can specify a shared memory zone for storing locks, thereby providing support for exclusive write locks as defined in the WebDAV specification. This allows multiple clients to collaborate on document editing without the risk of data corruption, as only one client can lock a resource at a time.
This directive must be used in conjunction with the 'dav_ext_lock_zone' directive, which defines the shared zone (name and size) that will be utilized for the locking mechanism. The shared zone holds lock entries and manages their lifetimes. The locking functionality is crucial for scenarios where resource integrity must be maintained during concurrent access. Therefore, it’s important to also define which HTTP methods can perform locking operations by utilizing the 'dav_ext_methods' directive, specifying LOCK and UNLOCK as prerequisites for proper functionality.
In scenarios where multiple locks are held, performance may degrade due to O(n) operations required for checking locks, making it critical to manage the number of concurrently held locks effectively to avoid potential performance bottlenecks.
Config Example
http {
dav_ext_lock_zone zone=my_locks:10m;
server {
location /files {
dav_ext_lock zone=my_locks;
dav_ext_methods LOCK UNLOCK;
}
}
}Ensure that the shared lock zone is properly defined with 'dav_ext_lock_zone' before using 'dav_ext_lock'.
Be cautious with lock timeout settings to avoid excessive locks held in memory, which can affect performance.
Make sure that relevant HTTP methods are enabled using 'dav_ext_methods' for full locking functionality.