How to use Webpack with Google Maps API?

serge1peshcoff picture serge1peshcoff · Nov 13, 2016 · Viewed 13.3k times · Source

I am using Webpack + html-webpack-plugin to build all my static files. The thing is, when I am using it with Google Maps API, it's not working.

I have this code:

var map;
function initMap() {
  map = new google.maps.Map(document.getElementById('map'), {
    center: {lat: -34.397, lng: 150.644},
    zoom: 6
  });
  // the other code, irrelevant
}

And a HTML file:

<!doctype html>
<html>
<head>
</head>
<body>
  <div id="map"></div>
  <script async="async" defer="defer"
      src="https://maps.googleapis.com/maps/api/js?key=<token here>&callback=initMap">
    </script>
   <script src="script.js"></script>
</body>
</html>

If I run just this file, everything works fine. But if I run this with, webpack it complaints about 'initMap is not a function'. I've looked inside the output, and it seems like initMap is declared not as global function, but as a function inside a module or something like that, so maybe that's the issue.

How should I use Google Maps API with webpack? I know that I can bundle some libs with my script, such as react, should I do the same? What should be the approach here?

UPD: Here is my webpack.config.js:

/* eslint-disable */
const path = require('path')
const fs = require('fs')
const webpack = require('webpack')
const HtmlWebpackPlugin = require('html-webpack-plugin')

const nodeModules = {}
fs.readdirSync('node_modules')
  .filter(function(x) {
    return ['.bin'].indexOf(x) === -1
  })
  .forEach(function(mod) {
    nodeModules[mod] = 'commonjs ' + mod
  })

const htmlMinifierObj = {
  collapseWhitespace: true,
  removeComments: true
}

module.exports = [
// the first object compiles backend, I didn't post it since it's unrelated
{
 name: 'clientside, output to ./public',
 entry: {
   script: [path.join(__dirname, 'clientside', 'script.js')]
 },
 output: {
   path: path.join(__dirname, 'public'),
   filename: '[name].js'
 },
 module: {
   loaders: [
     {
       test: /\.js$/,
       loader: 'babel',
       query: { presets:['es2015', 'stage-0'] }
     }
   ],
 },
 plugins: [
   //new webpack.optimize.UglifyJsPlugin({minimize: true}),
   new HtmlWebpackPlugin({
     template: 'clientside/index.html',
     inject: 'body',
     chunks: ['script'],
     minify: htmlMinifierObj
   })
 ],
}]

And the output HTML is (I've removed importing script.js from my source file, because it's added by webpack, and turned off the minimization, just for readability):

<!doctype html>
<html>
<head>
</head>
<body>
  <a href="/login/facebook">Login</a>
  <div id="map"></div>
  <script async defer
      src="https://maps.googleapis.com/maps/api/js?key=AIzaSyCGSgj5Ts10UdapzUnWlr34NS5cuoBj7Wg&callback=initMap">
    </script>
<script type="text/javascript" src="script.js"></script></body>
</html>

Answer

Danyel Cabello picture Danyel Cabello · Nov 13, 2016

In script.js

After your function declaration, add the function to the global scope, like this:

function initMap() {
    // Some stuff
}
window.initMap = initMap;