Per-method hooks

[bajtos]

A follow-up for #367.

As a LoopBack user, I want to execute my custom piece of code before/after a particular method is executed.

• the handler is async
• the handler can change input arguments and/or result (arguments passed to the callback)
• both static and prototype (instance) method can be overriden
• handlers are inherited by subclassed models

@raymondfeng suggested using a ctx object instead of a list of arguments in the handler

[ritch]

@bajtos - reopen if this shouldn't be closed.

[bajtos]

For anybody coming to this issue: we don't support per-method hooks, at least not at the level provided by Model class from loopback-datasource-juggler. There are other ways how to achieve this functionality, for example by using strong-remoting's before/after hooks, or by using a 3rd party library that can wrap model methods contributed by connectors into proxies allowing injections of custom code.