cls-bluebird

What is cls-bluebird?

The cls-bluebird npm package is a utility that integrates continuation-local storage (CLS) with the Bluebird promise library. This allows you to maintain context across asynchronous operations, which is particularly useful for things like request tracing, logging, and managing user sessions.

What are cls-bluebird's main functionalities?

Integrate CLS with Bluebird

This feature allows you to integrate CLS with Bluebird promises. The code sample demonstrates how to create a namespace, integrate it with Bluebird, and maintain context across asynchronous operations.

const cls = require('cls-hooked');
const ns = cls.createNamespace('myNamespace');
const Promise = require('bluebird');
require('cls-bluebird')(ns, Promise);

ns.run(() => {
  ns.set('key', 'value');
  Promise.resolve().then(() => {
    console.log(ns.get('key')); // Outputs: 'value'
  });
});

Maintain context in nested promises

This feature ensures that the context is maintained even in nested promises. The code sample shows how the context set in the outer promise is accessible in the inner promise.

const cls = require('cls-hooked');
const ns = cls.createNamespace('myNamespace');
const Promise = require('bluebird');
require('cls-bluebird')(ns, Promise);

ns.run(() => {
  ns.set('key', 'value');
  Promise.resolve().then(() => {
    return Promise.resolve().then(() => {
      console.log(ns.get('key')); // Outputs: 'value'
    });
  });
});

Other packages similar to cls-bluebird

cls-hooked

cls-hooked is a continuation-local storage library that works with async/await and other modern JavaScript features. Unlike cls-bluebird, it does not specifically integrate with Bluebird but can be used with any promise library.

async_hooks

async_hooks is a core Node.js module that provides an API to track asynchronous resources. It is more low-level compared to cls-bluebird and requires more manual setup but offers greater flexibility and is not limited to any specific promise library.

README

continuation-local-storage support for bluebird promises

Quick and dirty port from https://github.com/othiym23/cls-q

For documentation, check the above link. It works in the same way and uses the same tests.

Only difference is the call signature. You can provide a specific Bluebird constructor to be shimmed, rather than the default.

API: clsBluebird( ns [, Promise] )

var cls = require('continuation-local-storage');
var ns = cls.createNamespace('NODESPACE');

var Promise = require('bluebird');
var clsBluebird = require('clsBluebird');
clsBluebird(ns, Promise);

Changelog

1.1.0

• Remove peer dependencies
• Update shimmer dependency