How do you import a javascript package from a cdn/script tag in React?

Go to the index.html file and import the script

<script src="https://cdn.dwolla.com/1/dwolla.js"></script>

Then, in the file where dwolla is being imported, set it to a variable

const dwolla = window.dwolla;

This question is getting older, but I found a nice way to approach this using the react-helmet library which I feel is more idiomatic to the way React works. I used it today to solve a problem similar to your Dwolla question:

import React from "react";import Helmet from "react-helmet";export class ExampleComponent extends React.Component {    constructor(props) {        super(props);        this.state = {            myExternalLib: null        };        this.handleScriptInject = this.handleScriptInject.bind(this);    }    handleScriptInject({ scriptTags }) {        if (scriptTags) {            const scriptTag = scriptTags[0];            scriptTag.onload = () => {                // I don't really like referencing window.                console.log(`myExternalLib loaded!`, window.myExternalLib);                this.setState({                    myExternalLib: window.myExternalLib                });            };        }    }    render() {        return (<div>            {/* Load the myExternalLib.js library. */}            <Helmet                script={[{ src: "https://someexternaldomain.com/myExternalLib.js" }]}                // Helmet doesn't support `onload` in script objects so we have to hack in our own                onChangeClientState={(newState, addedTags) => this.handleScriptInject(addedTags)}            />            <div>                {this.state.myExternalLib !== null                    ? "We can display any UI/whatever depending on myExternalLib without worrying about null references and race conditions."                    : "myExternalLib is loading..."}            </div>        </div>);    }}

The use of this.state means that React will automatically be watching the value of myExternalLib and update the DOM appropriately.

Credit: https://github.com/nfl/react-helmet/issues/146#issuecomment-271552211

You can't require or import modules from a URL.

ES6: import module from URL

What you can do is make an HTTP request to get the script content & execute it, as in the answer for how to require from URL in Node.js

But this would be a bad solution since your code compilation would depend on an external HTTP call.

A good solution would be to download the file into your codebase and import it from there. You could commit the file to git if the file doesn't change much & are allowed to do it. Otherwise, a build step could download the file.