gavo.base.events module

General event handling.

Basically, everything roughly classified as user interaction should go through this module. gavo.base, on import, creates an instance of EventDispatcher and installs it as base.ui. The rest of the library can then call methods of base.ui.

Clients can then register observers (probably derived from base.observer.Observer) that subscribe to events and can display or log them in some form appropriate to the client.

class gavo.base.events.DispatcherType(name: str, bases: Tuple[type, ...], dict: Dict)

Bases: type

A metaclass for dispatching of messages.

Basically, you define methods called notify<whatever> in your class. For each of them, a subscribe<whatever> method is added.

Then, when notify<whatever> is called, your defined method is called, and its result is then passed to all callbacks passed in through subscribe<whatever>.

class gavo.base.events.EventDispatcher

Bases: object

is the central event dispatcher.

Events are posted by using notify* methods. Various handlers can then attach to them.

eventTypes = ['ExceptionMutation', 'NewSource', 'SourceError', 'SourceFinished', 'Shipout', 'IncomingRow', 'IndexCreation', 'ScriptRunning', 'Error', 'Failure', 'Warning', 'Info', 'Debug', 'WebServerUp', 'DBTableModified', 'ProcessStarts', 'ProcessEnded', 'Progress']

logOldExc(newExc: Exception) → Exception

notifies of and ExceptionMutation and returns newExc.

This is just a convenience when mutating exceptions.

notifyDBTableModified(*args: Any, **kwargs: Any) → Any

notifyDebug(*args: Any, **kwargs: Any) → Any

notifyError(*args: Any, **kwargs: Any) → Any

notifyExceptionMutation(*args: Any, **kwargs: Any) → Any

notifyFailure(*args: Any, **kwargs: Any) → Any

notifyIncomingRow(*args: Any, **kwargs: Any) → Any

notifyIndexCreation(*args: Any, **kwargs: Any) → Any

notifyInfo(*args: Any, **kwargs: Any) → Any

notifyNewSource(*args: Any, **kwargs: Any) → Any

notifyProcessEnded(*args: Any, **kwargs: Any) → Any

notifyProcessStarts(*args: Any, **kwargs: Any) → Any

notifyProgress(*args: Any, **kwargs: Any) → Any

notifyScriptRunning(*args: Any, **kwargs: Any) → Any

notifyShipout(*args: Any, **kwargs: Any) → Any

notifySourceError(*args: Any, **kwargs: Any) → Any

notifySourceFinished(*args: Any, **kwargs: Any) → Any

notifyWarning(*args: Any, **kwargs: Any) → Any

notifyWebServerUp(*args: Any, **kwargs: Any) → Any

subscribe(evName: str, callback: Callable[[...], None]) → None

subscribeDBTableModified(callback: Callable[[...], None]) → None

subscribeDebug(callback: Callable[[...], None]) → None

subscribeError(callback: Callable[[...], None]) → None

subscribeExceptionMutation(callback: Callable[[...], None]) → None

subscribeFailure(callback: Callable[[...], None]) → None

subscribeIncomingRow(callback: Callable[[...], None]) → None

subscribeIndexCreation(callback: Callable[[...], None]) → None

subscribeInfo(callback: Callable[[...], None]) → None

subscribeNewSource(callback: Callable[[...], None]) → None

subscribeProcessEnded(callback: Callable[[...], None]) → None

subscribeProcessStarts(callback: Callable[[...], None]) → None

subscribeProgress(callback: Callable[[...], None]) → None

subscribeScriptRunning(callback: Callable[[...], None]) → None

subscribeShipout(callback: Callable[[...], None]) → None

subscribeSourceError(callback: Callable[[...], None]) → None

subscribeSourceFinished(callback: Callable[[...], None]) → None

subscribeWarning(callback: Callable[[...], None]) → None

subscribeWebServerUp(callback: Callable[[...], None]) → None

suspended(evName: str) → Iterator[None]

a context manager suspending notification for a specific event.

This is mainly for use by test code that wants to avoid spilling too much junk into the log.

One weak point here is that any subscriptions entered while notification is suspended are lost. So: Don’t suspend notifications for normal code.

unsubscribe(evName: str, callback: Callable[[...], None]) → None

removes a callback from evName’s callback list.

It is not an error to unsubscribe a callback that’s not subscribed.

unsubscribeDBTableModified(callback: Callable[[...], None]) → None

unsubscribeDebug(callback: Callable[[...], None]) → None

unsubscribeError(callback: Callable[[...], None]) → None

unsubscribeExceptionMutation(callback: Callable[[...], None]) → None

unsubscribeFailure(callback: Callable[[...], None]) → None

unsubscribeIncomingRow(callback: Callable[[...], None]) → None

unsubscribeIndexCreation(callback: Callable[[...], None]) → None

unsubscribeInfo(callback: Callable[[...], None]) → None

unsubscribeNewSource(callback: Callable[[...], None]) → None

unsubscribeProcessEnded(callback: Callable[[...], None]) → None

unsubscribeProcessStarts(callback: Callable[[...], None]) → None

unsubscribeProgress(callback: Callable[[...], None]) → None

unsubscribeScriptRunning(callback: Callable[[...], None]) → None

unsubscribeShipout(callback: Callable[[...], None]) → None

unsubscribeSourceError(callback: Callable[[...], None]) → None

unsubscribeSourceFinished(callback: Callable[[...], None]) → None

unsubscribeWarning(callback: Callable[[...], None]) → None

unsubscribeWebServerUp(callback: Callable[[...], None]) → None