react.dev/tips/12-initial-ajax.md

---
id: initial-ajax
title: Load Initial Data via AJAX
layout: tips
permalink: tips/initial-ajax.html
prev: dom-event-listeners.html
next: false-in-jsx.html
---

Fetch data in `componentDidMount`. When the response arrives, store the data in state, triggering a render to update your UI.

When fetching data asynchronously, use `componentWillUnmount` to cancel any outstanding requests before the component is unmounted.

This example fetches the desired Github user's latest gist:

```js
var UserGist = React.createClass({
  getInitialState: function() {
    return {
      username: '',
      lastGistUrl: ''
    };
  },

  componentDidMount: function() {
    this.serverRequest = $.get(this.props.source, function (result) {
      var lastGist = result[0];
      this.setState({
        username: lastGist.owner.login,
        lastGistUrl: lastGist.html_url
      });
    }.bind(this));
  },

  componentWillUnmount: function() {
    this.serverRequest.abort();
  },

  render: function() {
    return (
      <div>
        {this.state.username}'s last gist is
        <a href={this.state.lastGistUrl}>here</a>.
      </div>
    );
  }
});

ReactDOM.render(
  <UserGist source="https://api.github.com/users/octocat/gists" />,
  mountNode
);
```