I try to integrate instantclick to my rails 6 application. I added the instantclick.js file in my javascript/custom folder. Then, I import it in javascript/packs/application.js:
require("custom/instantclick")
I added to the end of the body tag of my layout the following line to initialize instantclick:
...
<script data-no-instant>InstantClick.init();</script>
</body>
</html>
Then, I get the following error in console:
(index):404 Uncaught ReferenceError: InstantClick is not defined
I'm new to using webpacker, maybe I did something wrong. However, the instantclick.js file is imported. Any idea what I'm doing wrong? Thanks.
Webpack works differently than Sprockets. One thing you're running into is that webpack does not expose anything to the global scope. That means calling functions from a script tag won't work as expected unless you instruct webpack to add those variables to the window object.
Your instantclick.js file is also not module-aware, i.e, it does not export anything, such as with module.exports = InstantClick.
With webpack though, you can configure it to do both. You'll need to both export and expose InstantClick:
yarn add expose-loader exports-loader
// config/webpack/environment.js
const { environment } = require('#rails/webpacker')
environment.loaders.append('InstantClick', {
test: /instantclick/,
use: [{
loader: 'expose-loader',
options: 'InstantClick'
},
{
loader: 'exports-loader',
options: 'InstantClick'
}]
})
module.exports = environment
There is more to learn and other ways you can do it of course. Here are some resources:
https://webpack.js.org/guides/shimming/
http://www.matthiassommer.it/programming/expose-global-variables-methods-modules-javascript/
https://rossta.net/blog/three-ways-webpack-surprises-rails-developers.html
Related
TL;DR
I'm importing a css file into a typescript module, but the import resolves to a string instead of an object. Can anyone tell me why I don't get an object??
Example
// preview.ts
import test from './src/assets/test.theme.css';
// also tried this:
// import * as test from './src/assets/test.theme.css';
console.log('typeof test: ', typeof test);
console.log(test);
Console output
Detailed explanation
Actually, I'm trying to set up a Storybook for my Angular12 component library.
In order to provide various themes, I want to use the #etchteam/storybook-addon-css-variables-theme plugin, which in its documentation refers to the inline loader syntax of Webpack.
import myTheme from '!!style-loader?injectType=lazyStyleTag!css-loader!./assets/my-theme.css';
When applying this to my code my browser console started to complain
Error: myTheme.use is not a function
During my research I recognized that the imported stylesheet is not an evaluated javascript object, but instead it is provided as a string containing the sourcecode generated by the style-loader.
I also recognized, that this issue is not specific to the style-loader, but also occurs for all other loaders, e.g. css-loader, raw-loader, etc.
This issue is also not related to inline loader syntax, as it also shows up with loaders being defined in a minimalistic webpack config.
Environment:
Angular 12
Webpack 5
Reproduction
I have set up a GIT repo reproducing the issue.
The readme file explains the repro and the issue.
I think you have mistake in your Webpack config. You have nested rules property, instead you should have use:
{
rules: [
{
test: /\.css$/i,
use: ["style-loader", "css-loader"],
},
],
}
https://webpack.js.org/loaders/css-loader/
I'm sorry, but I have to revert my last statement. My issue has NOT been resolved by #Akxe's comment.
Now my import statement (import * as test from '...') resolves to an object, but it's still not correct.
I have set up a GIT Repo to reproduce the issue. The readme.md file explains the repro and the issue.
It looks like Webpack is not executing/evaluating the return value of the loader.
Btw. this is not just the case with the css-loader. The result stays the same for raw-loader, sass-loader, style-loader, etc.
My final goal is to lazily load my theme files into a storybook.
I try to follow the documentation of the #etchteam/storybook-addon-css-variables-> theme.
Finally I got my issue solved!
Analysis
The main issue here is the webpack configuration generated by the #angular-devkit/build-angular package. I was able to analyze it by debugging a fresh angular12 application (you can check it out here).
By setting a break-point at /node_modules/#angular-devkit/build-angular/src/utils/webpack-browser-config.js, function: generateWebpackConfig(...), I could inspect the final webpackConfig object in the debugger.
The relevant rule looks like this:
The important part here is the rule setting the module type to asset/source, instructing webpack not to evaluate the loader's result.
Solution concept 1: inline loader
With the help of alexander-kait and his great hints at this issue,
I was able to find an inline-loader syntax that overrides webpack's module declaration:
import Test from 'test.css.webpack[javascript/auto]!=!!!style-loader?injectType=lazyStyleTag!css-loader!./test.css';
console.log(typeof Test); // output: object
console.log(Test); // output: Object { use: () => void, unuse: () => void }
Test.use(); // this should usually be called by a theme switcher...
I'm not really sure about the url pattern here, as it seems to be an undocumented feature, but I assume that it's something like <query-pattern>.webpack[<module-type>]!=!<loaders><query>.
However, since this is an undocumented feature, I was rather reluctant to use it.
Solution concept 2: webpackConfig customization
Since I'm in a storybook context, I decided to customize the webpack configuration according to the storybook documentation.
My solution requires to set up a naming convention (e.g. *.theme.css).
// .storybook/main.js
module.exports = {
webpackFinal: async (config) => {
// exclude *.theme.css from the *.css ruleset
config.module.rules.find(rule => '.css'.match(rule.test)).exclude = [ /\.(?:theme\.css)$/i ];
// add a rule for *.theme.css
config.module.rules.push({
test: /\.(?:theme\.css)$/i,
use: [
{ loader: 'style-loader', options: { injectType: 'lazyStyleTag' } },
'css-loader',
],
});
},
};
With these rules in place, I can now simply do the following:
// preview.js
import LightTheme from './light.theme.css';
import DarkTheme from './dark.theme.css';
setupThemeSwitcher(LightTheme, DarkTheme);
Please note that the setupThemeSwitcher function is just pseudocode merely there for the example. In reality I'm using the #etchteam/storybook-addon-css-variables-theme addon...
I had a very similar issue with storybook and this extension, except l’m loading .scss files.
I simply adapted solution 2 to suit my .scss case and it works like a charm.
I couldn’t make solution 1 to work, but as stated, it sounds hacky whereas solution 2 is cleaner in my opinion.
Thanks a lot for sharing this solution, I was struggling for hours.
Good time of the day,
Recently I've been trying to implement dynamic module loading functionality for my project. However, I'm failing for past few hours. To give you an idea of what I'm trying to achieve, here is the structure of the project
plugins
developer
assets
scss
developer.scss
js
developer.js
themes
theme_name
webpack.mix.js
node_modules/
source
js
application.js
bootstrap.js
scss
application.scss
_variables.scss
So, in order to get the available plugins, I've made the following function
/**
* Get all plugins for specified developer
* which have 'assets' folder
* #param developerPath
* #param plugins
*/
function getDeveloperPlugins(developerPath, plugins) {
if (fs.existsSync(developerPath)) {
fs.readdirSync(developerPath).forEach(entry => {
let pluginPath = path.resolve(developerPath, entry),
assetsPath = path.resolve(pluginPath, 'assets');
if (fs.existsSync(assetsPath))
plugins[entry] = assetsPath;
});
}
}
This function loads all the available plugins for the specified developer, then goes inside and looks for the assets folder, if it exists, then it returns it and we can work with the provided directory later.
The next step is to generate the reference for every plugin (direct path to the developer_name.js file) which later should be 'mixed' into one plugins.bundle.js file.
In order to achieve this, the following piece of code 'emerged'
_.forEach(plugins, (directory, plugin) => {
let jsFolder = path.resolve(directory, 'js'),
scssFolder = path.resolve(directory, 'scss');
if (fs.existsSync(jsFolder)) {
webpackModules.push(jsFolder);
let possibleFile = path.resolve(jsFolder, plugin + '.js');
if (fs.existsSync(possibleFile))
pluginsBundle.js[plugin] = possibleFile;
}
if (fs.existsSync(scssFolder)) {
webpackModules.push(scssFolder);
let possibleFile = path.resolve(scssFolder, plugin + '.scss');
if (fs.existsSync(possibleFile))
pluginsBundle.scss[plugin] = possibleFile;
}
});
And the last step before I'm starting to edit the configuration of the Webpack is to get the folders for both scss and js files for all plugins and all developers:
let jsPluginsBundle = _.values(pluginsBundle.js),
scssPluginsBundle = _.values(pluginsBundle.scss);
And here is where the problems start to appear. I've tried many solutions offered either here on GitHub (in respective repositories), but I've failed so many times.
The only error I'm having now is this one:
ERROR in F:/Web/Projects/TestProject/plugins/developer/testplugin/assets/js/testplugin.js
Module build failed: ReferenceError: Unknown plugin "transform-object-rest-spread" specified in "base" at 0, attempted to resolve relative to "F:\\Web\\Projects\\TestProject\\plugins\\developer\\testplugin\\assets\\js"
Yes, i know that webpack.mix.js file should be in the root folder of the project, however, i'm just developing theme, which uses modules developed by other members of the team.
So, idea was to:
Start build process: npm run dev|prod
Load plugins for all needed developers automatically
Use methods and html tags provided by the plugin (it is a mix of PHP for API routing and Vue.js for Components, etc) as follows: <test-component></test-component>
Any help is really appreciated, i just cant get my head around that error. If you need extra information, i'm ready to help since i myself need help to solve this issue =)
Update: The latest Webpack config used by mix.webpackConfig() (still failing though)
let webpackConfiguration = {
module: {
rules: [{
test: /\.js$/,
exclude: /(node_modules|bower_components)/,
use: {
loader: require.resolve('babel-loader'),
options: {
presets: [
'babel-preset-env'
].map(require.resolve),
plugins: [
'babel-plugin-transform-object-rest-spread'
].map(require.resolve)
}
}
}]
},
resolve: {
modules: webpackModules
}
};
mix.webpackConfig(webpackConfiguration);
And this is the content of the webpackModules variable:
[
'F:\\Web\\Projects\\TestProject\\themes\\testtheme\\node_modules',
'F:\\Web\\Projects\\TestProject\\themes\\testtheme',
'F:\\Web\\Projects\\TestProject\\plugins\\developer\\testplugin\\assets\\js',
'F:\\Web\\Projects\\TestProject\\plugins\\developer\\testplugin\\assets\\scss'
]
Okay, after 7 hours I've decided to try the most obvious method to solve the problem, to create node_modules folder in the root of the project and install laravel-mix there, and it worked like a charm.
Looks like, if it cant find the module in the directory outside the root scope of the Webpack, it will go up the tree to find the node_modules folder.
Developers should allow us to set the root folder for Webpack to fetch all the modules i guess, but well, problem is solved anyways.
I've been using Webpack for my ES6 JS project and has been going well until I started to play with dynamic imports.
What I had that worked (router.js):
import { navigo } from "Navigo"; // router
import { clients } from "Controllers/clients.js";
const navigo = new Navigo();
navigo_router.on({
'/clients': () => {
clients.init();
}
});
But the more pages/routes I add, the more imports get stacked up in the head of the module. This is a relatively large app and I have a lot of pages/routes to add and therefore I need to load them dynamically to reduce the size of the initial page load.
So, following Webpack's documentation for dynamic imports, I tried the following which loads the controller module only when the relative route is called:
import { navigo } from "Navigo"; // router
const navigo = new Navigo();
navigo_router.on({
'/clients': () => {
import("Controllers/clients.js").then((clients) => {
clients.init();
});
}
});
But saving this in my editor resulted in a Babel transpiling error; SyntaxError: 'import' and 'export' may only appear at the top level, and clients.init() is not being called when tested in browser.
After a bit of reading, I discovered I needed a Babel plugin to transpile dynamic import() to require.ensure. So, I installed the plugin using the following command:
npm install babel-plugin-dynamic-import-webpack --save-dev
And declared the plugin in my babel.rc file
{ "plugins": ["dynamic-import-webpack"] }
After installing the plugin, the transpiling error disappeared and checking my transpiled code I found that the dynamic import()s has in fact been changed to require.ensure as expected. But now I get the following browser errors when testing:
Error: Loading chunk 0 failed.
Stack trace:
u#https://<mydomain.com>/js/app.bundle.js:1:871
SyntaxError: expected expression, got '<' 0.app.bundle.js:1
Error: Loading chunk 0 failed.
I didn't understand why it was referencing 0.app.bundle.js with the 0. prefix, so I checked my output/dist folder and I now have a new file in there called 0.app.bundle.js:
0.app.bundle.js 1,962bytes
app.bundle.js 110,656bytes
I imagine this new bundled file is the dynamically imported module, clients.js.
I only added dynamic importing to that one route and have left all the other routes as they were. So, during testing, I can view all routes except that one /clients route that now throws the above errors.
I'm totally lost at this point and hoped somebody could help push me over the finish line. What is this new file 0.app.bundle.js and how am I supposed to be using it/including it in my application?
I hope I've explained myself clearly enough and look forward to any responses.
I managed to fix my own problem in the end, so I will share what I discovered in an answer.
The reason the chunk file wasn't loading was because Webpack was looking in the wrong directory for it. I noticed in the Network tab of my developer console that the the chunk file/module was being called from my root directory / and not in /js directory where it belongs.
As per Webpack's documentation, I added the following to my Webpack config file:
output: {
path: path.resolve(__dirname, 'dist/js'),
publicPath: "/js/", //<---------------- added this
filename: 'app.bundle.js'
},
From what I understand, path is for Webpack's static modules and publicPath is for dynamic modules.
This made the chunk load correctly but I also had further issues to deal with, as client.init() wasn't being called and yielded the following error:
TypeError: e.init is not a function
To fix this, I also had to change:
import("Controllers/clients.js").then((clients) => {
clients.init();
});
To:
import("Controllers/clients.js").then(({clients}) => {
clients.init();
});
Note the curly braces in the arrow function parameter.
I hope this helps somebody else.
For debugging, you need to do
import("Controllers/clients.js").then((clients) => {
console.log(clients);
});
maybe working
import("Controllers/clients.js").then((clients) => {
clients.default.init();
});
So, i have a script that creates a global object
(function() {
window.GlobalThing = {}
})();
This script will also fill this object attributes
if (!GlobalThing .Resource) { GlobalThing .Resource = require('./Resource'); }
Then, some other scripts that are not bundled with webpack need to use this GlobalThing. I`ve tryed to make it global using ProvidePlugin for example:
plugins: [
new webpack.ProvidePlugin({
$: "jquery",
jQuery: "jquery",
"window.jQuery": "jquery",
'GlobalThing': path.join(__dirname,"Path/GlobalThing.js")
})
],
I've tryed adding an Alias as well
resolve: {
alias: {
'GlobalThing': path.join(__dirname,"Path/GlobalThing.js")
}
}
I have tryed doing something like this in the end of my GlobalThing.js file as well:
(function(){
window.GlobalThing = GlobalThing;
})();
Then i had to import to run the script, so i got a random js file inside the webpack to test it:
import GlobalThing from "GlobalThing ";
Still, it seems some scripts cannot seethe GlobalThing. If i bundle everything up with webpack, it works, but i didnt want to as our app is very old and have some very old stuff. Is there a way i can expose GlobalThing to those older scripts ?
ProvidePlugin takes a module name (i.e. string) and internally uses require to load it. So that wont help you in loading your own script.
That said, following should work:
Keep the GlobalThing script out of webpack bundling
Make sure the script itself is copied to the output folder
Make sure the index.html (or whatever html page you are using) has the scripts in the order GlobalThingScript.js followed by webpack bundle.js
To give you more insight:
When webpack bundles the scripts other than GlobalThingScript.js, it doesnt even know there is something called GlobalThing. It just bundles the other files.
That would mean it is upto you to make sure the GlobalThingScript.js is also made it to the final output folder. Also, the html source should use <script> tags to include the GlobalThingScript.js before webpack bundle.js.
In case problem persists, please do edit the OP to include the html source.
Hope that helps.
One of my module is external plugin (WOW effect), which needs to be initialize in index.html to works properly by using:
<script>
new WOW().init();
</script>
If I use the plugin as a completely external file - it works. But when I compile it with webpack it gives me an error:
Uncaught ReferenceError: wow is not defined.
My config file looks like this:
module.exports = {
entry: './modules/_entry.js',
output: {
filename: 'bundle.js'
}
};
and _entry.js contains:
require("./wow.js");
What I am doing wrong?
There are two possibilities:
Externals The benefit of this one is that you can easly exchange your local script file for example for a CDN one. In this method, the source of the script is an external vendor file.
Have a folder with you vendor scripts, like WOW.
Link to it in your HTML file using <script src="vendors/WOW.js">.
You are free to make the initialization like you indicated above, inside another <script> tag.
Add externals configuration to your webpack config:
var config = {
entry: [...],
output: {...},
externals: {
Wow: 'WOW'
},
module: {...},
plugins: [...]
};
From now on, you have access to an artificial module Wow in all your application modules and you can import or require them (although in case of WOW, I don't think you would need it).
Expose-loader This way lets you move to the global scope modules that you would normally use as... well, modules :) In this method, the source of the script is a module (either yours own, or installed with npm).
Install the plugin: npm install expose-loader --save-dev
Add the expose loader configuration to your webpack config file:
var config = {
entry: [...],
output: {...},
module: {
loaders: [{
...
}, {
test: 'path/to/your/module/wow.min.js',
loader: "expose?WOW"
}]
},
plugins: [...]
};
This should make the WOW a global variable, usable inside <script> tags.