npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2024 – Pkg Stats / Ryan Hefner

express-als-context

v1.0.3

Published

Get and set request-scoped context anywhere

Downloads

1,472

Readme

Express AsyncLocalStorage Context

Get and set request-scoped context anywhere. It's using a now-stable AsyncLocalStorage. It's heavily inspired by express-http-context, but doesn't suffer from the same memory leak issue that it brought (which was due to cls-hooked issue)

Support

AsyncLocalStorage supports Node.js from 12.17.0 up.

How to use it

Install: npm install --save express-als-context

Use the middleware immediately before the first middleware that needs to have access to the context. You won't have access to the context in any middleware .used before this one.

var express = require('express');
var httpContext = require('express-als-context');

var app = express();
// Use any third party middleware that does not need access to the context here, e.g. 
// app.use(some3rdParty.middleware);
app.use(httpContext.middleware);
// all code from here on has access to the same context for each request

Set values based on the incoming request:

// Example authorization middleware
app.use((req, res, next) => {
  userService.getUser(req.get('Authorization'), (err, result) => {
    if (err) {
      next(err);
    } else {
      httpContext.set('user', result.user)
      next();
    }
  });
});

You can read the values in the code that doesn't have access to the express's req object:

var httpContext = require('express-als-context');

// Somewhere deep in the Todo Service
function createTodoItem(title, content, callback) {
  var user = httpContext.get('user');
  db.insert({ title, content, userId: user.id }, callback);
}