System hooks
ⓘ
This page is about hooks that are called before or after a System call. You can also use store
hooks that are called whenever information in a table is modified, regardless of the source of
the change.
The namespace owner can register (opens in a new tab) hooks that are called before and/or after calls to a specific System.
System hook contracts
A system hook contract is a contract that implements the ISystemHook (opens in a new tab) interface.
This interface requires the implementation of two functions.
onBeforeCallSystem, which is called before the actual call.onAfterCallSystem, which is called afterward.supportsInterface, which is part of IEP-165 (opens in a new tab) used to specify which interfaces are supported by a contract.
To have the correct supportsInterface you can inherit from SystemHook (opens in a new tab).