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

apollo-link-context

v1.0.20

Published

An easy way to set and cache context changes for Apollo Link

Downloads

1,341,878

Readme


title: apollo-link-context description: Easily set a context on your operation, which is used by other links further down the chain.

The setContext function takes a function that returns either an object or a promise that returns an object to set the new context of a request.

It receives two arguments: the GraphQL request being executed, and the previous context. This link makes it easy to perform async look up of things like authentication tokens and more!

import { setContext } from "apollo-link-context";

const setAuthorizationLink = setContext((request, previousContext) => ({
  headers: {authorization: "1234"}
}));

const asyncAuthLink = setContext(
  request =>
    new Promise((success, fail) => {
      // do some async lookup here
      setTimeout(() => {
        success({ token: "async found token" });
      }, 10);
    })
);

Caching lookups

Typically async actions can be expensive and may not need to be called for every request, especially when a lot of request are happening at once. You can setup your own caching and invalidation outside of the link to make it faster but still flexible!

Take for example a user auth token being found, cached, then removed on a 401 response:

import { setContext } from "apollo-link-context";
import { onError } from "apollo-link-error";

// cached storage for the user token
let token;
const withToken = setContext(() => {
  // if you have a cached value, return it immediately
  if (token) return { token };

  return AsyncTokenLookup().then(userToken => {
    token = userToken;
    return { token };
  });
});

const resetToken = onError(({ networkError }) => {
  if (networkError && networkError.name ==='ServerError' && networkError.statusCode === 401) {
    // remove cached token on 401 from the server
    token = null;
  }
});

const authFlowLink = withToken.concat(resetToken);