responsive-loader with nuxt.js - vue.js

Question

I want to integrate responsive-loader into my Nuxt.js project which runs in SPA mode. (Optional I want to add Vuetify Progressive Image support also).
It will be a static hosting with Netlify.
Versions:
"nuxt": "^2.3.4"
"responsive-loader": "^1.2.0"
"sharp": "^0.21.1"
I found some solutions how to do it (https://stackoverflow.com/a/51982357/8804871) but this is not working for me.
When I run npm run build
I get an error message: "TypeError: Cannot set property 'exclude' of undefined"
My build section looks the following:
build: {
transpile: [/^vuetify/],
plugins: [
new VuetifyLoaderPlugin()
],
extractCSS: true,
/*
** Run ESLint on save
*/
extend(config, { isDev, isClient, isServer }) {
// Default block
if (isDev && isClient) {
config.module.rules.push({
enforce: 'pre',
test: /\.(js|vue)$/,
loader: 'eslint-loader',
exclude: /(node_modules)/
})
}
if (isServer) {
config.externals = [
nodeExternals({
whitelist: [/^vuetify/]
})
]
}
// Default block end
// here I tell webpack not to include jpgs and pngs
// as base64 as an inline image
config.module.rules.find(
rule => rule.loader === "url-loader"
).exclude = /\.(jpe?g|png)$/;
/*
** Configure responsive-loader
*/
config.module.rules.push({
test: /\.(jpe?g|png)$/i,
loader: "responsive-loader",
options: {
min: 350,
max: 2800,
steps: 7,
placeholder: false,
quality: 60,
adapter: require("responsive-loader/sharp")
}
});
}
}
The error is probably found in this section:
config.module.rules.find(
rule => rule.loader === "url-loader"
).exclude = /\.(jpe?g|png)$/;
Like said I get this error message: "TypeError: Cannot set property 'exclude' of undefined".
I run this project along with vuetify. I also would like to enable the Progressive image support together with responsive loader. Does anybody know how to setup both rules together?
https://github.com/vuetifyjs/vuetify-loader#progressive-images

Answer 1

The easiest way to integrate responsive-loader into a Nuxt.js project is to use this module: https://www.npmjs.com/package/nuxt-responsive-loader
Disclaimer: I created the module

Answer 2

The problem with your config that it relies on rule.loader property but rule can be defined in use or oneOf config sections as well.
Another one problem is that nuxt internal config has several rules with url-loader(for images, videos, fonts ...).
In your case the rule, you tried to find, has use section and url-loader is defined there, that's why your find function found nothing and threw this error:
{
"test": /\.(png|jpe?g|gif|svg|webp)$/,
"use": [{
"loader": "url-loader",
"options": {
"limit": 1000,
"name": "img/[hash:7].[ext]"
}
}]
}
About responsive-loader, you should remove extensions you want to process with responsive-loader from url-loader rule to avoid unexpected behavior and conflicts, here is extend function working example:
extend(config, ctx) {
let imgTest = '/\\.(png|jpe?g|gif|svg|webp)$/';
// find by reg ex string to not rely on rule structure
let urlRule = config.module.rules.find(r => r.test.toString() === imgTest);
// you can use also "oneOf" section and define both loaders there.
// removed images from url-loader test
urlRule.test = /\.(svg|webp)$/;
config.module.rules.push({
test: /\.(png|jpe?g|gif)$/,
loader: "responsive-loader",
options: {
// place generated images to the same place as url-loader
name: "img/[hash:7]-[width].[ext]",
min: 350,
max: 2800,
steps: 7,
placeholder: false,
quality: 60,
adapter: require("responsive-loader/sharp")
}
})
}
Yes, it looks dirty, but I think it's only way for now to change some loader.
What about vuetify - I think both loaders will conflict with each other and probably the solution is to use single loader that will work with your images.
Hope it helps.
Update for Nuxt >= 2.4.0:
They modified the rules array please update the following line:
let imgTest = '/\\.(png|jpe?g|gif|svg|webp)$/i';
Then the code should work normally again.