preposttrigger

Preposttrigger is a term used to describe a hook mechanism that allows code to run immediately before and after a designated operation or event within a software system. It combines pre-triggers (pre-hooks) and post-triggers (post-hooks) as related concepts that can be enabled separately or together to influence behavior around an operation.

In practice, a pretrigger runs before the operation completes; it can inspect, modify, or veto the input. A posttrigger runs after the operation finishes; it can log, update derived data, synchronize external systems, or trigger further workflows. Pre and post triggers may be implemented via native database triggers (BEFORE or AFTER), event listeners, middleware, or plugin architectures.

Common use cases include data validation and normalization, access control checks, audit logging, cache or materialized view maintenance, and integration with external services. They provide extension points for systems to enforce business rules, maintain consistency, or coordinate complex workflows without modifying core logic.

Design considerations for preposttriggers include execution order, error handling, and transactional boundaries. Pre-triggers may abort operations, so they should be deterministic and lightweight; post-triggers should be idempotent and resilient to failures. Caution is warranted to avoid side effects, recursion, or performance bottlenecks introduced by trigger chains.

Relation to other concepts: preposttrigger functionality is commonly described in contexts with ORMs and workflow engines and is closely related to middleware, hooks, or event listeners. See also triggers, hooks, and event-driven architectures.