panel.io.watcher module#

Shared file watching for the autoreload development loop.

Components that render from the same file, e.g. every component compiled into a shared ESM bundle, would otherwise each start their own watcher task. This module hands out one watcher per path and notifies all its subscribers when the file changes.

class panel.io.watcher.PathWatcher(path: Path)[source]#

Bases: object

Watches a single path on behalf of any number of subscribers.

Subscribers are held weakly, so subscribing does not keep a component alive; each is notified by calling the method it subscribed with.

Attributes:

running

Methods

`subscribe`(obj, method)	Subscribes an object to changes of the watched path.
`unsubscribe`(obj[, method])	Unsubscribes an object, either from a single method or entirely.

subscribe(obj: Any, method: str) → None[source]#

Subscribes an object to changes of the watched path.

Parameters:

obj: Any: The object to notify, held weakly.
method: str: Name of the method to invoke on the object.

unsubscribe(obj: Any, method: str | None = None) → None[source]#: Unsubscribes an object, either from a single method or entirely.

panel.io.watcher.current_path_watchers() → dict[Path, PathWatcher][source]#: Returns the watchers that have been created so far.

panel.io.watcher.get_path_watcher(path: str | PathLike) → PathWatcher[source]#: Returns the process-wide watcher for the given path, creating it on first use.