What is xhr2?
The xhr2 npm package is a server-side implementation of the XMLHttpRequest API, which is commonly used in web browsers for making HTTP requests. This package allows Node.js applications to make HTTP requests using the familiar XMLHttpRequest interface.
What are xhr2's main functionalities?
Basic GET Request
This feature allows you to make a basic GET request to a specified URL. The code sample demonstrates how to open a connection, send the request, and handle the response.
const XMLHttpRequest = require('xhr2');
const xhr = new XMLHttpRequest();
xhr.open('GET', 'https://jsonplaceholder.typicode.com/posts/1', true);
xhr.onload = function () {
if (xhr.status >= 200 && xhr.status < 300) {
console.log(xhr.responseText);
} else {
console.error('Request failed with status:', xhr.status);
}
};
xhr.send();
POST Request with Data
This feature allows you to make a POST request with data. The code sample demonstrates how to set the request method to POST, set the appropriate headers, and send JSON data in the request body.
const XMLHttpRequest = require('xhr2');
const xhr = new XMLHttpRequest();
xhr.open('POST', 'https://jsonplaceholder.typicode.com/posts', true);
xhr.setRequestHeader('Content-Type', 'application/json;charset=UTF-8');
xhr.onload = function () {
if (xhr.status >= 200 && xhr.status < 300) {
console.log(xhr.responseText);
} else {
console.error('Request failed with status:', xhr.status);
}
};
xhr.send(JSON.stringify({ title: 'foo', body: 'bar', userId: 1 }));
Handling Errors
This feature allows you to handle errors that may occur during the request. The code sample demonstrates how to handle both HTTP status errors and network errors.
const XMLHttpRequest = require('xhr2');
const xhr = new XMLHttpRequest();
xhr.open('GET', 'https://jsonplaceholder.typicode.com/invalid-url', true);
xhr.onload = function () {
if (xhr.status >= 200 && xhr.status < 300) {
console.log(xhr.responseText);
} else {
console.error('Request failed with status:', xhr.status);
}
};
xhr.onerror = function () {
console.error('Network error occurred');
};
xhr.send();
Other packages similar to xhr2
axios
Axios is a promise-based HTTP client for the browser and Node.js. It provides a more modern and flexible API compared to xhr2, including support for promises and async/await, which makes it easier to handle asynchronous operations.
node-fetch
Node-fetch is a lightweight module that brings the Fetch API to Node.js. It is similar to xhr2 in that it allows you to make HTTP requests, but it uses the modern Fetch API, which is more widely used in modern web development.
request
Request is a simplified HTTP client for Node.js. It provides a more user-friendly API compared to xhr2 and supports features like cookies, redirects, and multipart form data. However, it has been deprecated in favor of more modern alternatives like axios and node-fetch.
XMLHttpRequest Emulation for node.js
This is an npm package that implements the
W3C XMLHttpRequest specification on top
of the node.js APIs.
Supported Platforms
This library is tested against the following platforms.
Keep in mind that the versions above are not hard requirements.
Installation and Usage
The preferred installation method is to add the library to the dependencies
section in your package.json
.
{
"dependencies": {
"xhr2": "*"
}
}
Alternatively, npm
can be used to install the library directly.
npm install xhr2
Once the library is installed, require
-ing it returns the XMLHttpRequest
constructor.
var XMLHttpRequest = require('xhr2');
MDN (the Mozilla Developer Network) has a
great intro to XMLHttpRequest.
Versioning
The library aims to implement the
W3C XMLHttpRequest specification, so
the library's API will always be a (hopefully growing) subset of the API in the
specification.
Copyright and License
The library is Copyright (c) 2013 Victor Costan, and distributed under the MIT
License.