I have been working with React for the last two years. One of the questions many React beginners ask: "What's the React way to fetch data from the server" or "How should I make AJAX calls in React"? To answer your question, as many developers would tell you, React is just a view library and you are free to use whatever you are comfortable with. However, this doesn't help much - especially when the JavaScript landscape is changing so rapidly. So, in this article I will try to answer this basic question and list down 5 simple libraries for making AJAX calls in React.

jQuery $.ajax

This is a quick & dirty way to make AJAX calls. In the former, official React tutorial, they use jQuery to fetch data from the server. If you are just starting out and are playing around with React, this can save you a lot of time. Many of us are already familiar with jQuery. So, it won't take a lot of time to understand and use it in React. Here is how a simple API call is made, with jQuery:

loadCommentsFromServer: function() {
      $.ajax({
      url: this.props.url,
      dataType: 'json',
      cache: false,
      success: function(data) {
        this.setState({data: data}); // Notice this
      }.bind(this),
      error: function(xhr, status, err) {
        console.error(this.props.url, status, err.toString());
      }.bind(this)
    });
  }

P.S. Snippet is from React's former official tutorial.

It's the same old jQuery's $.ajax used inside a React component. Notice how this.setState() is called inside the success callback. This is how you update the state with data obtained from the API call.

However, jQuery is a big library with many functionalities - So, it doesn't make sense to use it just for making API calls (Unless you are already using it for a bunch of other tasks). So, what's the alternative? What should we use? The answer is fetch API.

Fetch API

Fetch is a new, simple and standardised API that aims to unify fetching across the web and replace XMLHttpRequest. It has a polyfill for older browsers and should be used in modern web apps. If you are making API calls in Node.js you should also check out node-fetch which brings fetch to Node.js.

Here is what the modified API call looks like :

loadCommentsFromServer: function() {
    fetch(this.props.url).then(function(response){
        // perform setState here
    });
}

In most modern React tutorials you will find fetch being used. To know more about fetch, check out the following links :

• Mozilla
• David Walsh Blog
• Google Developers
• WHATWG

Superagent

Superagent is a light weight AJAX API library created for better readability and flexibility. If due to some reason, you don't want to use fetch, you should definitely check this out. Here is a snippet to demonstrate its usage :

loadCommentsFromServer: function() {
    request.get(this.props.url).end(function(err,res){
        // perform setState here
    });
}

Superagent also has a Node.js module with the same API. If you are building isomorphic apps using Node.js and React, you can bundle superagent using something like webpack and make it available on the client side. As the APIs for client and server are the same, no code change is required in order to make it work in the browser.

Axios

Axios is a promise based HTTP client for Node.js and browser. Like fetch and superagent, it can work on both client and server. It has many other useful features which you can find on their GitHub page.

Here is how you make an API call using Axios :

loadCommentsFromServer: function() {
    axios.get(this.props.url).then(function(response){
      // perform setState here
    }).catch(function(error){
      //Some error occurred
    });
}

Request

This list will be incomplete without request library which was designed with simplicity in mind. With more that 12k GitHub stars, it's also one of the most popular Node.js modules. You can find more about request module on their GitHub page.

Sample usage :

loadCommentsFromServer: function() {
    request(this.props.url, function(err, response, body){
          // perform setState here
    });
}

My Take

As fetch is the new standardised API to interact with remote resources, I would suggest using it for all your AJAX needs (not only in React, but all types of JavaScript apps).