GatsbyJS & Superagent: WebpackError: require is not a function

Question

I'm trying to build my react app into static html pages with gatsbyjs. I just tried 'gatsby build', and it goes through everything fine until it wants to create the static pages, then I get:

error Building static HTML for pages failed

See our docs page on debugging HTML builds for help


  1 | if (global.GENTLY) require = GENTLY.hijack(require);   2 |
> 3 | var crypto = require('crypto');
    | ^   4 | var fs = require('fs');   5 | var util = require('util'),   6 |     path = require('path'),


  WebpackError: require is not a function

  - incoming_form.js:3 Object.map../file
    ~/formidable/lib/incoming_form.js:3:1

  - index.js:1 Object.<anonymous>
    ~/formidable/lib/index.js:1:1

  - index.js:8 Object.<anonymous>
    ~/superagent/lib/node/index.js:8:1

  - contact.js:3 Object.<anonymous>
    src/pages/contact.js:3:1

  - sync-requires.js:8 Object.exports.__esModule
    .cache/sync-requires.js:8:53

I am using npm 5.5.1.

Edit:

So I just commented out superagent in my contact.js file, and the build goes through fine. However, I don't understand why this should cause any problems:

contact.js:

import request from 'superagent'

export default class Contact extends React.Component {

  constructor(props) {
    super(props);
    this.state = { showThankYou: false};

    this.handleSubmit = this.handleSubmit.bind(this);
  }

handleSubmit(e) {
    e.preventDefault();

    request.post('http://www.mywebsite.com/email.php') 
    .send(new FormData(document.getElementById('myForm')))
    .end(function(err, res){
      if (err || !res.ok) {
        console.log('Oh no! error' + err);
      } else {
        console.log('yay got it');
      }
    });

    document.getElementById("myForm").reset();
    this.setState({showThankYou: true});
  }


render() {  
    return (
    <div className="row">

        <div className="form_wrapper">
          <div>
            <form id="myForm" onSubmit={this.handleSubmit}> 

              <label htmlFor="fname">First Name</label>
              <input type="text" id="fname" name="fname" />

              <label htmlFor="lname">Last Name</label>
              <input type="text" id="lname" name="lname" />

              <label htmlFor="email">E-mail Address</label>
              <input type="text" id="email" name="email" />

              <label htmlFor="message">Message</label>
              <textarea id="message" name="message" style={{height: "100px"}}></textarea>

              <input type="submit" value="Submit" />

            </form>
          </div>
        </div>    
    </div>);
}
}

Cattish

Answer 1

I ran into this same error (coming from Auth0 in my case). I was able to resolve it by modifying the webpack config.

Gatsby v1

In gatsby-node.js add:

exports.modifyWebpackConfig = ({ config, stage }) => {
  config.plugin("webpack-define", webpack.DefinePlugin, [{ "global.GENTLY": false }])

  return config;
};

Gatsby v2

In gatsby-node.js add:

exports.onCreateWebpackConfig = ({ stage, actions, plugins }) => {
  actions.setWebpackConfig({
    plugins: [
      plugins.define({
        'global.GENTLY': false
      })
    ]
  })
}

I ended up running into other problems because auth0-lock doesn't support server side rendering, but this solved the require is not a function error.

Unmoved

You also need to const webpack = require('webpack') to get webpack.DefinePlugin – Diathermy