I realise there is some debate about using webpacker in Rails engines but I have a simple usecase and currently have a workaround. Would like to know of a better (the best?) solution.
In this rails engine I have webpacker setup in the "spec/dummy" directory and everything works well in dev:
https://github.com/RealEstateWebTools/property_web_scraper/tree/master/spec/dummy/config/webpack
When the engine is used by a rails app however it will not find the compiled webpack files so each time I have a release ready I compile the webpack files and manually copy them to the vendor directory:
https://github.com/RealEstateWebTools/property_web_scraper/tree/master/vendor/assets/javascripts
I then require that file here:
https://github.com/RealEstateWebTools/property_web_scraper/blob/master/app/assets/javascripts/property_web_scraper/spp_vuetify.js
In my layout I use the above file using the good old sprockets "javascript_include_tag": https://github.com/RealEstateWebTools/property_web_scraper/blob/master/app/views/layouts/property_web_scraper/spp_vuetify.html.erb
In the layout there is a check to see if I'm running the "spec/dummy" app in which case I will user webpacker as it would normally be used in dev.
There must be a better way than this.
Webpacker has been retired
https://github.com/rails/webpacker
Going forward, it's better to switch to jsbundling-rails with webpack.
(I would rather suggest esbuild as it's "10×-100× faster")
But let's do it with webpack:
rails new webpack-in-engine --javascript webpack --css tailwind --database postgresql
In app/javascript/application.js I do:
console.log("hello from application.js")
And it works.
Now with an engine:
rails plugin new admin --mountable
Then depends:
Separate JS
Add an entry to your webpack.config.js:
const path = require("path")
const webpack = require("webpack")
module.exports = {
mode: "production",
devtool: "source-map",
entry: {
application: "./app/javascript/application.js",
admin: "./admin/app/javascript/admin.js"
},
output: {
filename: "[name].js",
sourceMapFilename: "[name].js.map",
path: path.resolve(__dirname, "app/assets/builds"),
},
plugins: [
new webpack.optimize.LimitChunkCountPlugin({
maxChunks: 1
})
]
}
<%= javascript_include_tag "admin", "data-turbo-track": "reload", defer: true %>
Shared JS
<%= javascript_include_tag "application", "data-turbo-track": "reload", defer: true %>
And in your app/javascript/application.js:
import "./../../admin/app/javascript/admin"
See full repo https://github.com/dorianmariefr/webpack-in-engine
Aside: Also I would rather namespace in the main app than have engines. I think engines are for very specific use cases not namespacing.
Related
How to use tailwind in a rails engine? According to the documentation supplying a css argument to the Rails generator should work
Rails 7.0.2.2 engine generated using
rails plugin new tailtest --mountable --full -d postgresql --css tailwind
This generates the engine with Postgresql but does nothing with tailwind at all, and following manual installation instructions fail too.
Running, as per documentation, bundle add tailwindcss-rails adds tailwind to the gemfile rather than the engines tailtest.gemspec
So after adding the dependency to the gemspec
spec.add_dependency "tailwindcss-rails", "~> 2.0"
and running bundle install does install the engine however the rest of the manual installation fails
then adding the require to lib/engine.rb
require "tailwindcss-rails"
module Tailtest
class Engine < ::Rails::Engine
isolate_namespace Tailtest
end
end
then running the install process fails
rails tailwindcss:install
Resolving dependencies...
rails aborted!
Don't know how to build task 'tailwindcss:install' (See the list of available tasks with `rails --tasks`)
Did you mean? app:tailwindcss:install
Obviously the app:tailwindcss:install command fails too.
So I am probably missing an initializer of some sort in the engine.rb file but no idea on what it should be.
It is the same idea as How to set up importmap-rails in Rails 7 engine?. We don't need to use the install task. Even if you're able to run it, it's not helpful in the engine (see the end of the answer for explanation).
Also rails plugin new doesn't have a --css option. To see available options: rails plugin new -h.
Update engine's gemspec file:
# my_engine/my_engine.gemspec
spec.add_dependency "tailwindcss-rails"
Update engine.rb:
# my_engine/lib/my_engine/engine.rb
module MyEngine
class Engine < ::Rails::Engine
isolate_namespace MyEngine
# NOTE: add engine manifest to precompile assets in production, if you don't have this yet.
initializer "my-engine.assets" do |app|
app.config.assets.precompile += %w[my_engine_manifest]
end
end
end
Update assets manifest:
# my_engine/app/assets/config/my_engine_manifest.js
//= link_tree ../builds/ .css
Update engine's layout:
# my_engine/app/views/layouts/my_engine/application.html.erb
<!DOCTYPE html>
<html>
<head>
<%#
NOTE: make sure this name doesn't clash with anything in the main app.
think of it as `require` and `$LOAD_PATH`,
but instead it is `stylesheet_link_tag` and `manifest.js`.
%>
<%= stylesheet_link_tag "my_engine", "data-turbo-track": "reload" %>
</head>
<body> <%= yield %> </body>
</html>
bundle show command will give us the path where the gem is installed, so we can copy a few files:
$ bundle show tailwindcss-rails
/home/alex/.rbenv/versions/3.1.2/lib/ruby/gems/3.1.0/gems/tailwindcss-rails-2.0.8-x86_64-linux
Copy tailwind.config.js file from tailwindcss-rails:
$ cp $(bundle show tailwindcss-rails)/lib/install/tailwind.config.js config/tailwind.config.js
Copy application.tailwind.css file into any directory to fit your setup:
$ cp $(bundle show tailwindcss-rails)/lib/install/application.tailwind.css app/assets/stylesheets/application.tailwind.css
Because tailwindcss-rails uses standalone executable, we don't need node or rails to compile the stylesheets. We just need to get to the executable itself.
Executable is located here https://github.com/rails/tailwindcss-rails/tree/v2.0.8/exe/. Instead of running the build task https://github.com/rails/tailwindcss-rails/blob/v2.0.8/lib/tasks/build.rake we can just call the executable directly.
$ $(bundle show tailwindcss-rails)/exe/tailwindcss -i app/assets/stylesheets/application.tailwind.css -o app/assets/builds/my_engine.css -c config/tailwind.config.js --minify
Use -w option to start watch mode.
$ $(bundle show tailwindcss-rails)/exe/tailwindcss -i app/assets/stylesheets/application.tailwind.css -o app/assets/builds/my_engine.css -c config/tailwind.config.js --minify -w
The output file should match the name in stylesheet_link_tag "my_engine".
Now that you have a plain my_engine.css file, do with it what you want. Use it in the layout, require it from the main app application.css. The usual rails asset pipeline rules apply.
If you want to put all that into a task, use Engine.root to get the paths.
# my_engine/lib/tasks/my_engine.rake
task :tailwind_engine_watch do
require "tailwindcss-rails"
# NOTE: tailwindcss-rails is an engine
system "#{Tailwindcss::Engine.root.join("exe/tailwindcss")} \
-i #{MyEngine::Engine.root.join("app/assets/stylesheets/application.tailwind.css")} \
-o #{MyEngine::Engine.root.join("app/assets/builds/my_engine.css")} \
-c #{MyEngine::Engine.root.join("config/tailwind.config.js")} \
--minify -w"
end
From the engine directory:
$ bin/rails app:tailwind_engine_watch
+ /home/alex/.rbenv/versions/3.1.2/lib/ruby/gems/3.1.0/gems/tailwindcss-rails-2.0.8-x86_64-linux/exe/x86_64-linux/tailwindcss -i /home/alex/code/stackoverflow/my_engine/app/assets/stylesheets/application.tailwind.css -o /home/alex/code/stackoverflow/my_engine/app/assets/builds/my_engine.css -c /home/alex/code/stackoverflow/my_engine/config/tailwind.config.js --minify -w
Rebuilding...
Done in 549ms.
Make your own install task if you have a lot of engines to set up:
desc "Install tailwindcss into our engine"
task :tailwind_engine_install do
require "tailwindcss-rails"
# NOTE: use default app template, which will fail to modify layout, manifest,
# and the last command that compiles the initial `tailwind.css`.
# It will also add `bin/dev` and `Procfile.dev` which we don't need.
# Basically, it's useless in the engine as it is.
template = Tailwindcss::Engine.root.join("lib/install/tailwindcss.rb")
# TODO: better to copy the template from
# https://github.com/rails/tailwindcss-rails/blob/v2.0.8/lib/install/tailwindcss.rb
# and customize it
# template = MyEngine::Engine.root("lib/install/tailwindcss.rb")
require "rails/generators"
require "rails/generators/rails/app/app_generator"
# NOTE: because the app template uses `Rails.root` it will run the install
# on our engine's dummy app. Just override `Rails.root` with our engine
# root to run install in the engine directory.
Rails.configuration.root = MyEngine::Engine.root
generator = Rails::Generators::AppGenerator.new [Rails.root], {}, { destination_root: Rails.root }
generator.apply template
end
Install task reference:
https://github.com/rails/rails/blob/v7.0.2.4/railties/lib/rails/tasks/framework.rake#L8
https://github.com/rails/tailwindcss-rails/blob/v2.0.8/lib/tasks/install.rake
Watch task reference:
https://github.com/rails/tailwindcss-rails/blob/v2.0.8/lib/tasks/build.rake#L10
Update How to merge two tailwinds.
Above setup assumes the engine is its own separate thing, like admin backend, it has its own routes, templates, and styles. If an engine functionality is meant to be mixed with the main app, like a view_component collection, then tailwind styles will override each other. In this case isolating engine styles with a prefix could work:
https://tailwindcss.com/docs/configuration#prefix
The reason that tailwind styles don't mix is because most of the selectors have the same specificity and the order is very important.
So here is an example. Main app with an engine, both using tailwind, both compile styles separately, tailwind configs are only watching one file from the engine and one from the main app, only using #tailwind utilities; directive:
Engine template, that we want to use in the main app, should work fine:
<!-- blep/app/views/blep/_partial.html.erb -->
<div class="bg-red-500 sm:bg-blue-500"> red never-blue </div>
But when rendered in the main app it never turns blue. Here is the demonstration set up:
<!-- app/views/home/index.html.erb -->
<%= stylesheet_link_tag "blep", "data-turbo-track": "reload" %>
<%= stylesheet_link_tag "tailwind", "data-turbo-track": "reload" %>
<!-- output generated css in the same order as above link tags -->
<% require "open-uri" %>
<b>Engine css</b>
<pre><%= URI.open(asset_url("blep")).read %></pre>
<b>Main app css</b>
<pre><%= URI.open(asset_url("tailwind")).read %></pre>
<div class="bg-red-500"> red </div> <!-- this generates another bg-red-500 -->
<br>
<%= render "blep/partial" %>
And it looks like this:
/* Engine css */
.bg-red-500 {
--tw-bg-opacity: 1;
background-color: rgb(239 68 68 / var(--tw-bg-opacity))
}
#media (min-width: 640px) {
.sm\:bg-blue-500 {
--tw-bg-opacity: 1;
background-color: rgb(59 130 246 / var(--tw-bg-opacity))
}
}
/* Main app css */
.bg-red-500 {
--tw-bg-opacity: 1;
background-color: rgb(239 68 68 / var(--tw-bg-opacity))
}
<div class="bg-red-500"> red </div>
<br>
<div class="bg-red-500 sm:bg-blue-500"> red never-blue </div>
^ you can hit run and click "full page". Main app bg-red-500 selector is last so it overrides engines sm:bg-blue-500 selector, media queries don't add to specificity score. It's the same reason you can't override, say, mt-1 with m-2, margin top comes later in the stylesheet. This is why #layer directives are important.
The only way around this is to watch the engine directory when running tailwind in the main app, so that styles are compiled together and in the correct order. Which means you don't really need tailwind in the engine:
module.exports = {
content: [
"./app/**/*",
"/just/type/the/path/to/engine/views",
"/or/see/updated/task/below",
],
}
Other ways I tried, like running 6 tailwind commands for each layer for main app and engine, so that I can put them in order, better but was still out of order a bit and duplicated. Or doing an #import and somehow letting postcss-import know where to look for engine styles (I don't know, I just symlinked it into node_modules to test), but this still required tailwind to watch engine files.
I did some more digging, tailwind cli has a --content option, which will override content from tailwind.config.js. We can use it to setup a new task:
namespace :tailwindcss do
desc "Build your Tailwind CSS + Engine"
task :watch do |_, args|
# NOTE: there have been some updates, there is a whole Commands class now
# lets copy paste and modify. (debug = no --minify)
command = Tailwindcss::Commands.watch_command(debug: true, poll: false)
# --content /path/to/app/**/*,/path/to/engine/**/*
command << "--content"
command << [
Rails.root.join("app/views/home/*"),
Blep::Engine.root.join("app/views/**/*.erb")
].join(",")
p command
system(*command)
end
# same for build, just call `compile_command`
# task :build do |_, args|
# command = Tailwindcss::Commands.compile_command(debug: false)
# ...
end
https://github.com/rails/tailwindcss-rails/blob/v2.0.21/lib/tasks/build.rake#L11
That answer by Alex is really good, i wish i had it when starting out. (But i didn't even have the question to google)
Just want to add two things:
1- a small simplification. I just made a script to run tailwind in the engine
#!/usr/bin/env sh
# Since tailwind does not install into the engine, this will
# watch and recompile during development
# tailwindcss executable must exist (by bundling tailwindcss-rails eg)
tailwindcss -i app/assets/stylesheets/my_engine.tailwind.css \
-o app/assets/stylesheets/my_engine/my_engine.css \
-c config/tailwind.config.js \
-w
2- For usage in an app, that obviously also uses tailwind, i was struggling, since the two generated css's were biting each other and i could not get both styles to work in one page. Always one or the other (app or engine) was not styled right. Until i got the app's tailwind to pick up the engines classes.
Like so:
Add to the app's tailwind.config.js: before the module
const execSync = require('child_process').execSync;
const output = execSync('bundle show my_engine', { encoding: 'utf-8' });
And then inside the content as last line
output.trim() + '/app/**/*.{erb,haml,html,rb}'
Then just include the apps generated tailwind css in the layout, like the installer will. Don't include the engines stylesheet in the layout, or add it to the asset
I am working with rails 5.1.7. and trying to migrate from the asset pipeline to webpacker, I have already run rake assets:precompile
I am getting this message:
Webpacker can't find logo.png in /***/public/packs/manifest.json. Possible causes:
1. You want to set webpacker.yml value of compile to true for your environment
unless you are using the `webpack -w` or the webpack-dev-server.
2. webpack has not yet re-run to reflect updates.
3. You have misconfigured Webpacker's config/webpacker.yml file.
4. Your webpack configuration is not creating a manifest.
Your manifest contains:
{
"application.js": "/packs/js/application-a5be4c0a9f54fffa5cb7.js",
"application.js.map": "/packs/js/application-a5be4c0a9f54fffa5cb7.js.map",
"entrypoints": {
"application": {
"js": [
"/packs/js/application-a5be4c0a9f54fffa5cb7.js"
],
"js.map": [
"/packs/js/application-a5be4c0a9f54fffa5cb7.js.map"
]
}
}
}
That's after setting my images in app/javascript/images in which I verified logo.png is there.
The line prompting this issue is:
<%= link_to asset_pack_path('logo.png', alt: 'logo', width: 150), locale_root_path, class: 'logo'%>
If I just simply remove that line it will lead me to the path of another different image that is also in that folder (app/javascript/image).
I have this extract to configure the image path in my app/javascript/packs/application.js file is:
const images = require.context('../images', true)
const imagePath = (name) => images(name, true)
Webpack needs to be configured to compile your images:
In your app/javascript directory, create an images folder, and place the logo.png inside.
image_tag has been changed to image_pack_tag now that your images are being compiled with webpack. However, by default you would have to pass in the entire image path each time, beginning with media/, followed by the path from your webpack source path, which is defined in you webpacker.yml config file. For example:
<%= image_pack_tag 'media/images/logo.png', alt: 'logo', width: 150%>
To solve this, you can use require.context:
In your webpage entry point, by default this is located in app/javascript/packs/application.js, you should add the following line:
const images = require.context("../images", true);
To access the logo image in your view, you can now use:
<%= image_pack_tag 'logo.png', alt: 'logo', width: 150%>
First you need to tell webpack that you want to use this image file, so (for example) in your app/javascript/packs/application.js file put:
require.context('../images', true)
Then confirm that the images are indeed compiled into the manifest.
then to put this image into the link, try (I'm not totally sure webpacker can deal with this) image_pack_tag('media/images/logo.png')
Give it a try and let us know what happens.
I'm running Rails v5 with Webpacker v2. Everything's been smooth so far, but I've hit one hiccup: how to expose Rails helpers to my TypeScript.
I know Webpacker ships with rails-erb-loader, so I was expecting that I'd be able to add .erb to a TypeScript file, and then import that file elsewhere:
// app/javascript/utils/rails.ts.erb
export const env = "<%= Rails.env %>"
export function isEnv(envName: string) {
return env == envName
}
// app/javascript/packs/application.ts
import { env } from "../utils/rails"
But Webpack can't find the "rails" file even if I modify the typescript loader to include ERB files:
module.exports = {
test: /.ts(\.erb)?$/,
loader: 'ts-loader'
}
All I see is:
error TS2307: Cannot find module '../utils/rails'.
What's the best way to go about exposing Rails helpers and variables to my JavaScript?
Rails env comes from your environment variable. This means you configure it by setting (in bash for example) the variable in this way:
export RAILS_ENV=production
As a consequence, you don't need to deal with Rails at all.
// app/javascript/utils/rails.ts.erb
export const env = process.env.RAILS_ENV || "development"
export function isEnv(envName: string) {
return env == envName
}
This comes with a great advantage: you don't have to load the whole rails app just to compile your javascript. Rails can become really slow on first load if your app grows.
Since you won't have access to process.env on the frontend (browser), you also need a way to make it exist. In webpack, this is done through the DefinePlugin:
Update your webpack configuration to use the plugin (in plugins section): new webpack.DefinePlugin({ "process.env": { RAILS_ENV: process.env.RAILS_ENV } }) and you will get a process.env.RAILS_ENV available in the client
Rails Env can be accessed through:
process.env.RAILS_ENV
I am trying to compile my Rails app assets using RAILS_ENV=production bundle exec rake assets:precompile, but this doesn't compile my AngularJS assets, so my console report this:
ActionController::RoutingError (No route matches [GET] "/assets/app/views/products/index.html"):
My AngularJS assets are under "/assets/app/", so I tried to compile the angular folders by adding following into my production.rb but still not working.
config.assets.precompile += %w(app/* bootstrap/* datatable/* ....
I can find the compiled index file under this path:
public/assets/app/views/products/index-2429bd0f8fc0762dcc075e51f0306c5b.html
Any idea?
UPDATE
Also tried config.serve_static_assets = false in production, but it cause more missing assets errors
Thanks
I've worked through this in my app by using constants to get the path structure right.
my angular app is journey (yours would obviously be different)
so I declare the angular app as a module
this.journey = angular.module('journey', [
'ngResource',
'ngRoute'
]);
Then I have a file called constants.js.erb where I declare my templates
journey.constant('INDEX_TEMPLATE', '<%= asset_path('journeys/journey_index.html')%>');
journey.constant('EDIT_JOURNEY_TEMPLATE', '<%= asset_path('journeys/journey_edit.html') %>');
Finally in my services I use the constants declared as the template url
journey.config([
'$routeProvider',
'$locationProvider',
'INDEX_TEMPLATE',
'EDIT_JOURNEY_TEMPLATE',
function ($routeProvider, $locationProvider, INDEX_TEMPLATE, EDIT_JOURNEY_TEMPLATE) {
$locationProvider.html5Mode(false);
return $routeProvider.when('/', {
templateUrl: INDEX_TEMPLATE,
controller: 'JourneyIndexController'
})
}
])
This way I don't have to worry about where the files are or how rails is organising the routing.
Hope this helps
I have a Rails 4 application with
<%= javascript_include_tag "modernizr", "data-turbolinks-track" => true %>
in the head. In development, the following HTML is rendered, and modernizr is loaded:
<script data-turbolinks-track="true" src="/assets/modernizr.js?body=1"></script>
In production, the followign HTML is rendered, and modernizr is not loaded (404 not found):
<script data-turbolinks-track="true" src="/javascripts/modernizr.js"></script>
In production, /assets/modernizr.js is found and browsable.
The Rails documentation says that the javascript_include_tag should generate
<script data-turbolinks-track="true" src="/assets/modernizr.js?body=1"></script>
In production, my stylesheet_link_tags are fine, linking to the /assets/ directory.
Why is the javascript_include_tag linking to /javascripts instead of /assets in production, and how can I fix it?
One of the usage statements for AssetUrlHelper indicates it will produce /javascripts/ urls
like what you are seeing:
# asset_path "application", type: :javascript # => /javascripts/application.js
(from asset_url_helper.rb line 117 - [1])
This code looks like it can only be reached if the precompiled asset is missing
so it would appear that your asset compilation is not working (my deployments usually
fail when that happens, so maybe yours isn't even firing).
The same asset_url_helper.rb calls the /javascripts/ part 'extname' and
uses the following map to know how to generate the name:
# Maps asset types to public directory.
ASSET_PUBLIC_DIRECTORIES = {
audio: '/audios',
font: '/fonts',
image: '/images',
javascript: '/javascripts',
stylesheet: '/stylesheets',
video: '/videos'
}
A new Rails 4 app has this in the config/environments/production.rb
# Do not fallback to assets pipeline if a precompiled asset is missed.
config.assets.compile = false
which seems to match the behavior you are seeing.
By default, Rails only precompiles application.js, application.css and any images it finds in the assets path. Therefore, in production mordernizr will not get precompiled and thus the javascript helpers will not be able to find the file.
In order to fix the issue, you can add modernizr to the precompile list by modifying the following config in production.rb
config.assets.precompile += ['modernizr.js']
For more information see the Rails Guides
Be sure to precompile your assets in production by running this command:
RAILS_ENV=production bundle exec rake assets:precompile
The Rails Guide on the asset pipeline can give you more details: http://guides.rubyonrails.org/asset_pipeline.html#precompiling-assets
I have a new application using Rails 4 deployed on Heroku with :
<%= javascript_include_tag "application", "data-turbolinks-track" => true %>
my javascript application.(fingerprint).js called from the src: assets/application.js
i think your problem come from something into your production.rb who define assets from another location.
So maybe you can add Moderniz.js to
config.assets.precompile = ['.js', '.css', '*.css.erb']
in config/production.rb
Or simply require modernizr script into your application.js
//= require mordernizr
and remove the modernizr script call into your layout.
<%= javascript_include_tag "modernizr", "data-turbolinks-track" => true %>
Can you check from where your application.js is served into your production environment ?
It may be because this file needs to be in /vendor/assets/javascript instead of /app/assets/javascript. The Vendor folder is for javascript libraries, and the App folder is for your code.
A better solution than adding a tag to your layout would be adding a script reference to your application.js and let the sass compiler compress and attach it to your main javascript file.
If you don't get a definitive answer, check out:
http://guides.rubyonrails.org/asset_pipeline.html#asset-organization