Hookpoint NPM | npm.io

hookPoint

hooks system for custom plugins

Installation

npm install hookpoint

Hook types

Each hook triggers every added function in a loop.

SeriesHook. This hook simply calls every function added in a row.
LastOutHook. A bail hook allows exiting early. When any of the tapped function returns anything, the bail hook will stop executing the remaining ones.
Waterfall. A waterfall hook also calls each added function in a row. It passes a return value from each function to the next function.

All hooks allow exiting early. To exit early a method must be passed to the constructor for detecting this case.

Usage

All Hook constructors take one optional argument, which is a list of argument names as strings.

const hook = new SeriesHook<[string, number], boolean>();

The best practice is to expose all hooks of a class in a hooks property:

class HttpFile {
	constructor() {
		this.hooks = {
			parse: new SeriesHook<[String, ParseContext], ParseResult>(),
			replaceVariables: new WaterfallHook<[string, ReplaceVariableContext], string>()
		};
	}
}

Other people can now use these hooks:

const httpFile = new HttpFile();
httpFile.hooks.parse.addHook("javascript", (text, context) => addExecuteAction(text));

It's required to pass a id to identify the plugin/reason.

Interception

All Hooks offer an additional interception API:

httpFile.hooks.parse.addInterceptor({
	 beforeLoop: async function checkUserCancellation(
      hookContext: models.HookTriggerContext<[models.ProcessorContext], boolean>
    ) {
      const context = hookContext.args[0];
      if (context.progress?.isCanceled?.()) {
        log.trace('process canceled by user');
        return false;
      }
      return true;
    },
})