@vizydrop/correlation-id/lib/correlator.js

Vizydrop correlation id helper based on async hooks

/*********************************************************************
* © Copyright IBM Corp. 2025
*********************************************************************/
const cls = require('cls-hooked');
const uuid = require('uuid');

function validateOptions(opts = {}) {
    if (opts.generateDefaultId && typeof opts.generateDefaultId !== 'function') {
        throw new Error('generateDefaultId must be a function');
    }

    if (opts.namespaceName && typeof opts.namespaceName !== 'string') {
        throw new Error('namespaceName must be a string');
    }
}

module.exports = function correlator(opts = {}) {
    validateOptions(opts);

    const store = cls.createNamespace(opts.namespaceName || 'correlation-id-namespace');

    function generateDefaultId() {
        return opts.generateDefaultId ? opts.generateDefaultId() : uuid.v4();
    }

    const CORRELATION_ID_KEY = 'correlation-id';

    function withId(id, fn) {
        store.run(() => {
            store.set(CORRELATION_ID_KEY, id || generateDefaultId());
            fn();
        });
    }

    function getId() {
        return store.get(CORRELATION_ID_KEY);
    }

    function withIdAndReturn(id, fn) {
        return store.runAndReturn(() => {
            store.set(CORRELATION_ID_KEY, id || generateDefaultId());
            return fn();
        });
    }

    return {
        withIdAndReturn,
        withId,
        getId,
        bindEmitter: store.bindEmitter.bind(store),
        bind: store.bind.bind(store),
        generateId: generateDefaultId,
    };
};