bcquality/microsoft/knowledge/events/name-events-by-publisher-position.md

bc-version	domain	keywords	technologies	countries	application-area
all	events	event-naming onbefore onafter conventions discoverability integration-event publisher	al	w1	all

Name events by publisher position

Description

An event name should tell a subscriber where in the publisher the event fires. The convention encodes the position: an event at the very start of a procedure or trigger is OnBefore<Name>; one at the very end is OnAfter<Name>; one in the middle names both the host routine and the local boundary, as On<Name>OnBefore<Context> or On<Name>OnAfter<Context>. Consistent, position-encoding names make events discoverable and predictable, and let developers and tooling reason about firing order without reading the publisher. Ad-hoc names such as MyCustomEvent or BeforePost hide where the event fires and break the conventions the ecosystem relies on.

Best Practice

Name by position: OnBeforePostSalesLine and OnAfterPostSalesLine at the routine boundaries, and OnPostSalesLineOnAfterCalcAmounts for an event raised partway through PostSalesLine after an amount calculation. The name alone then tells a subscriber both the host routine and the exact point it runs.

See sample: name-events-by-publisher-position.good.al.

Anti Pattern

Ad-hoc event names that omit the host routine or the before/after position (MyCustomSalesEvent, BeforePost, SalesLineEvent), leaving subscribers unable to tell when the event fires relative to the publisher's logic. Detection: publisher names that do not follow the OnBefore/OnAfter<Routine> or On<Routine>OnBefore/OnAfter<Context> patterns.

See sample: name-events-by-publisher-position.bad.al.