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Upgrading Encore and your assets/ Setup


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Just two recipes left to update! Let's do webpack-encore-bundle next. This recipe changed quite a bit over the past year and a half, so depending on how old your version is, this might be easy.... or maybe not so easy. Hmm, let's say that it might be "interesting".

To see what we're working with, run:

git status

Ok: we have a number of modified and deleted files and some conflicts. Let's go through those first, starting with assets/app.js. As you can see, I enabled some custom Collapse functionality from bootstrap. I'm not sure why this conflicted, but it's an easy fix.

16 lines | assets/app.js
// ... lines 1 - 13
// activates collapse functionality
import { Collapse } from 'bootstrap';

Next is bootstrap.js. This might actually be a new file for you, depending on how old your recipe was. The job of this file is to initialize the Stimulus JavaScript library and load all of the files in the controllers/ directory as Stimulus controllers. In this case, I already had this file, but apparently the expression for how it finds the files changed slightly. The new version is probably better, so let's use that.

12 lines | assets/bootstrap.js
// ... lines 1 - 3
export const app = startStimulusApp(require.context(
// ... lines 5 - 6
// ... lines 9 - 12

Next up is controllers.json. I'm not sure why this is conflicting either... I have a feeling that I may have added these files manually in the past... and now the recipe upgrade is re-adding them. I want to keep my custom version.

12 lines | assets/controllers.json
"controllers": {
"@symfony/ux-chartjs": {
// ... lines 4 - 7
"entrypoints": []

Next up is styles/app.css. The same thing happened here. The recipe added this file... all the way at the bottom... with just a body background-color. I must have added this file manually... so conflict! Keep all of our custom stuff and... good!

138 lines | assets/styles/app.css
@import "~bootstrap";
body {
font-family: spartan;
color: #444;
// ... lines 7 - 138

Hello @hotwired/Stimulus v3

The last conflict is down here in package.json. This one is a bit more interesting. My project was already using Stimulus: I have stimulus down here and also Symfony's stimulus-bridge. The updated recipe now has @hotwired/stimulus, and instead of "@symfony/stimulus-bridge": "^2.0.0", it has "@symfony/stimulus-bridge": "^3.0.0".

So what's going on? First, Stimulus version 3 was released. Yay! But... the only real difference between version 2 and 3 is that they renamed the library from stimulus to @hotwired/stimulus. And in order to get version 3 to work, we also need version 3 of stimulus-bridge... instead of 2.

So let's take this as a golden opportunity to upgrade from Stimulus 2 to Stimulus 3. As a bonus, after upgrading, you'll get cool new debugging messages in your browser's console when working with Stimulus locally.

Anyways, keep @hotwired/stimulus... but move it up so it's in alphabetical order. Use version 3 of stimulus-bridge... and even though it doesn't really matter since this version constraint allows any version 1, I'll also use the new webpack-encore version... and then fix the conflict. Oh, and be sure to delete stimulus. We don't want version 2 of stimulus hanging around and confusing things.

24 lines | package.json
"devDependencies": {
"@hotwired/stimulus": "^3.0.0",
// ... line 4
"@symfony/stimulus-bridge": "^3.0.0",
// ... line 6
"@symfony/webpack-encore": "^1.7.0",
// ... lines 8 - 13
// ... lines 15 - 22

Fantastic! Because we just changed some files in package.json, find your terminal tab that's rocking Encore, hit "ctrl" + "C", and then run:

yarn install


npm install

Perfect! Now restart Encore:

yarn watch

And... it fails!? That's a long error message... but it eventually says:

assets/controllers/answer-vote_controller.js contains a reference to the file "stimulus".

The most important, but boring part of upgrading from Stimulus 2 to 3 is that you need to go into all of your controllers and change import { Controller } from 'stimulus' to import { Controller } from '@hotwired/stimulus'.

import { Controller } from '@hotwired/stimulus';
// ... lines 2 - 22

But it's that simple. I'm also going to delete hello_controller.js... this is just an example controller that the recipe gave us. In the last controller, change to @hotwired/stimulus.

15 lines | assets/controllers/user-api_controller.js
import { Controller } from '@hotwired/stimulus';
// ... lines 2 - 15

Awesome! Stop yarn watch again.. and re-run it:

yarn watch

Dang! We still get an error! This is coming from @symfony/ux-chartjs/dist/controller.js.

Upgrading UX Libraries

In my project, I've installed one of the Symfony UX packages, which are PHP packages that also give you some JavaScript. Apparently, the JavaScript for that package is still referencing stimulus instead of the new @hotwired/stimulus. What this tells me is that I probably need to upgrade that PHP package. So, in composer.json, down here on symfony/ux-chartjs, if you do some research, you'll find out that there's a new version 2 out that supports Stimulus 3.

111 lines | composer.json
// ... lines 2 - 5
"require": {
// ... lines 7 - 37
"symfony/ux-chartjs": "^2.0",
// ... lines 39 - 45
// ... lines 47 - 109

After changing that, find your main terminal tab and run:

composer up symfony/ux-chartjs

to upgrade that one package. And... nice! We've upgraded to version 2.1.0. Now it wants us to run:

npm install --force


yarn install --force

That re-initializes the JavaScript from the package. One thing I want to highlight for this particular package is that when we upgraded to version 2 in our composer.json file, Flex then updated our chart.js dependency from version 2.9 to 3.4. That's because the JavaScript in this new version is meant to work with chart.js 3 instead of chart.js 2. Flex made that change for us. We don't need to do anything here, but it's good to be aware of that.

At last! We should be ready to go. Run

yarn watch

and... got it! Successful build! Over in the main terminal tab, let's add everything... since we fixed all of the conflicts... and commit!

Upgrading Foundry's Recipe

Now, dear friends, we are on the last update. It's zenstruck/foundry. This is an easy one. Run:

git status

It is, once again, environment configuration going into a main file. So let's commit that.

when@dev: &dev
# See full configuration:
# Whether to auto-refresh proxies by default (
auto_refresh_proxies: true
when@test: *dev

And... we're done! All of our recipes are updated! And remember, part of the reason we did all of this is because some of those recipes replaced old deprecated code with new shiny code. Hopefully, when we refresh the page, our site will not only still work, but will have less deprecations. On my project, if I refresh a few times, it looks like I'm settling in at about 22. Progress!

We do need to squash those deprecations. But next, one other thing we need to do is... upgrade our code to PHP 8! This is another spot where Rector can help!