Struct zookeeper_async::recipes::cache::PathChildrenCache

pub struct PathChildrenCache { /* fields omitted */ }

A Path Cache is used to watch a znode.

A utility that attempts to keep all data from all children of a ZK path locally cached. This will watch the ZK path; whenever a child is added, updated or removed, the Path Cache will change its state to contain the current set of children, the children's data and the children's state. You can register a listener that will get notified when changes occur.

Note

It is not possible to stay transactionally in sync. Users of this class must be prepared for false-positives and false-negatives. Additionally, always use the version number when updating data to avoid overwriting another process's change.

Implementations

impl PathChildrenCache

pub async fn new<'_>(
    zk: Arc<ZooKeeper>,
    path: &'_ str
) -> ZkResult<PathChildrenCache>

Create a new cache instance watching path. If path does not exist, it will be created (see ZooKeeperExt::ensure_path).

Note

After creating the instance, you must call start.

pub async fn get_current_data<'_>(&'_ self) -> Data

Return the current data. There are no guarantees of accuracy. This is merely the most recent view of the data.

pub async fn clear<'_>(&'_ self)

pub fn start(&mut self) -> ZkResult<()>

Start the cache. The cache is not started automatically. You must call this method.

pub fn add_listener<Listener: Fn(PathChildrenCacheEvent) + Send + 'static>(
    &self,
    subscriber: Listener
) -> Subscription

pub fn remove_listener(&self, sub: Subscription)