Exclusively

Exclusively is a simple class that provides methods for executing async functions exclusively.

Features

Calls fetch() or other async functions exclusively.

Installation

npm install exclusively

Usage

fetch resources sequentially

import Exclusively from "exclusively";

const request = new Request("https://example.com/");

/* JavaScript fetch() function */

                 // Network waterfall (example)
fetch(request);  // |----|
fetch(request);  // |-------|
fetch(request);  // |--|


/* Exclusively fetch() method */
const context = new Exclusively();

                         // Network waterfall (example)
context.fetch(request);  // |---|
context.fetch(request);  //     |-----|
context.fetch(request);  //           |----|

call async functions sequentially

import Exclusively from "exclusively";

const wait3s = async () => new Promise(resolve => setTimeout(() => {
    console.log("3s");
    resolve();
}, 3000));

/* print "3s" three times every three seconds. */
const context = new Exclusively();

                       // execution time
context.exec(wait3s);  // |---|
context.exec(wait3s);  //     |---|
context.exec(wait3s);  //         |---|

share "Exclusively" instance among multiple script files

sample1.js

import Exclusively from "exclusively";

const context = Exclusively.getContext("sample");  // get context named "sample" (if it does not exist, it will be created)

context.fetch("https://example.com/");

sample2.js

import Exclusively from "exclusively";

const context = Exclusively.getContext("sample");  // same object as "const context" in sample1.js

context.fetch("https://example.com/");

multiple contexts

import Exclusively from "exclusively";

const request = new Request("https://example.com/");

const context1 = new Exclusively();
const context2 = new Exclusively();

                          // Network waterfall (example)
context1.fetch(request);  // |---|
context2.fetch(request);  // |----|
context1.fetch(request);  //     |----|
context2.fetch(request);  //      |--|
context1.fetch(request);  //          |----|
context2.fetch(request);  //         |----|

globalThis.fetch

Exclusively.prototype.fetch() calls globalThis.fetch() internally. The Fetch API has been available by default since Node.js 18, but for earlier versions, globalThis.fetch() must be defined in some way. One of the ways is to install node-fetch.

npm install node-fetch

Then, import fetch() and set it as a member of globalThis.

import fetch from "node-fetch";
import Exclusively from "exclusively";

globalThis.fetch = fetch;