https://github.com/koajs/middleware-hook

low-level hooks for your middleware
https://github.com/koajs/middleware-hook

Last synced: about 1 month ago
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low-level hooks for your middleware

• Host: GitHub
• URL: https://github.com/koajs/middleware-hook
• Owner: koajs
• Created: 2015-10-15T05:23:49.000Z (almost 9 years ago)
• Default Branch: master
• Last Pushed: 2016-01-01T07:07:41.000Z (over 8 years ago)
• Last Synced: 2024-03-21T13:16:53.579Z (6 months ago)
• Language: JavaScript
• Homepage:
• Size: 4.88 KB
• Stars: 5
• Watchers: 9
• Forks: 2
• Open Issues: 1
• Metadata Files:
  • Readme: Readme.md
  • Changelog: History.md

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• awesome-koa - middleware-hook - low-level hooks for your middleware (Middleware)

README

        

# koa-middleware-hook

low-level hooks for your middleware. this is mostly an experiment,

but it lets you hook into the following spots:

  1. Downstream: Beginning of the middleware

  2. Downstream: Before yielding to the next middleware in the stack

  3. Upstream: Beginning on the way back up the stack

  4. Upstream: When the middleware finishs

useful for profiling your middleware, logging your middleware, timing your middleware, etc.

probably not suitable for production, though I haven't profiled it or anything.

## Install

```

npm install koa-middleware-hook

```

## Usage

##### `hook = Hook(function: marker, function: reduce)`

`marker` is a function called during each point in time where you'd return what you want to track. Here's an example:

```js

function marker () {

  return new Date()

}

```

`reduce` takes all 4 hooks and allows you to merge them together in some meaningful way. Something to keep in mind is that the innermost middleware will only execute 2 hooks:

```js

function reduce (middleware_name, downstream_start, downstream_end | upstream_end, upstream_start | null, upstream_end | null) {

  if (arguments.length === 3) {

    debug('%s: %sms', middleware_name, downstream_end - downstream_start)

  } else {

    debug('%s: %sms', middleware_name, (downstream_end - downstream_start) + (upstream_end - upstream_start))

  }

}

```

Here's how you use hook:

```

app.use(hook(bodyparser()))

```

## TODO

- solicit ideas for a better API

- some more usage examples

## License

MIT