I am developing Rails 5 application and use assets pipeline.
It work well in development mode, but if I try to run it in production mode, it can't load images & styles correctly.
I checked and found that it is because
config.assets.compile = false
in config/environments/production.rb
Unless I set it true, it doesn't work at all.
I know live compilation isn't good for production, what is solution?
There are two options related to serving assets within a Rails server:
Asset compilation
config.assets.compile = true
refers to asset compilation. That is, whether Rails should recompile the assets when it detects that a new version of the source assets is there. In development, you want to have it set to true, so that your styles get compiled when you edit the css files. With the next request, Rails will automatically recompile the assets. On production, you usually want to set it to false and handle asset compilation during deployment. For this, you have to run
RAILS_ENV=production bin/rails assets:precompile
Usually, if you deploy using Capistrano, it takes care of that.
Asset serving
The second option related to assets is
config.public_file_server.enabled
This describes whether it is Rails that should serve the compiled files from the public/assets directory. In development, you want that, so it's true by default. In production, you usually don't want to fire up your web server to serve the logo image or a css file, so you probably compile the assets and then host them separately (for example, on a CDN like cloudfront). If you still want them to be served in production, you can launch Rails with:
RAILS_SERVE_STATIC_FILES=true RAILS_ENV=production bin/rails server
Precompile your assets first.
Run RAILS_ENV=production rake assets:precompile to generate your stylesheets and js files in your public directory.
Related
I read the docs but can't seem to understand if you have to run rake assets:precompile locally each time you change scss file or any other assets? Isn't there an automatic way to do it? One of the things I have noticed is that I forget to run it sometimes and my heroku changes do not appear. There must be a way to set it up automatically in rails?
If I change
config.assets.compile = false
to true, will do that it? Is a disadvantage of doing that?
You don't have to precompile your assets for Heroku to serve them. Heroku will precompile your assets automatically if you have not already precompiled assets locally. Read this heroku doc regarding the asset pipeline in Rails 3 (even if you are already using Rails 4). Then read this doc regarding the asset pipeline in Rails 4 on heroku.
Pay particular attention to this part:
If a public/assets/manifest.yml is detected in your app, Heroku will
assume you are handling asset compilation yourself and will not
attempt to compile your assets. Rails 4 uses a file called
public/assets/manifest-.json instead. On both versions you
can generate this file by running $ rake assets:precompile locally and
checking the resultant files into Git.
rake assets:precompile must be run for production environment. Do not need to run the command for the development environment. The command is used to collect all files into one and so be lighter to serve in production. Under development the styles they are wanted in the assets folder. After running the command, the styles are placed in the public folder.
If you forget to run rake assets:precompile Heroku should do it automatically. One reason it may not be is if you have checked your public folder into git as then during slug compilation Heroku will assume you precompiled your assets and will not do it for you.
Setting config.assets.compile = true can slow down your application by a lot, which is why it is only used in development.
rake assets:precompile currently spits everything into my public/assets directory when I was under the impression (after setting up S3) that it would push up to Amazon. I am utilizing asset_sync as outlined here
Currently I have this in my application.rb:
class Application < Rails::Application
config.assets.enabled = true
config.assets.digest = true
end
Then in my development.rb I have:
config.action_controller.asset_host = "//#{ENV['FOG_DIRECTORY_DEV']}.s3.amazonaws.com"
config.action_mailer.asset_host = "http://#{ENV['FOG_DIRECTORY_DEV']}.s3.amazonaws.com"
config.assets.initialize_on_precompile = false
What am I doing wrong here?
You must appreciate that asset_sync is there to sync your assets (not replace them)
Asset Sync
The gem itself will let Rails publish your assets "locally" (to /public/assets), and then it will essentially push them all to your S3 bucket, replicating them.
As described by the gem's documentation:
Synchronises Assets between Rails and S3.
Asset Sync is built to run with the new Rails Asset Pipeline feature
introduced in Rails 3.1. After you run bundle exec rake
assets:precompile your assets will be synchronised to your S3 bucket,
optionally deleting unused files and only uploading the files it needs
to.
--
Fix
In regards to your problem, I'm sure that by default, development assets are served dynamically - meaning that if you want to run them as static (precompiled), you'll have to tweak some of the settings which define this:
#config/environments/development.rb
# Debug mode disables concatenation and preprocessing of assets.
# This option may cause significant delays in view rendering with a large
# number of complex assets.
config.assets.debug = false #true
This should enable you to use the precompiled assets locally (in development), which will in turn allow you to use S3
Production serves static assets by default, meaning the most applicable way to test asset_sync is literally by deploying to your production environment. However, you should be able to use the code above to get it to work in development, too
Precompiling assets on the production server is very slow. So I have decided to recompile them on the development machine and upload assets to the Amazon S3 by jammit. Everything's done but I have some negative problems:
I have to include public/assets directory to git control. Because if public/assets directory is empty on the production server fails
If I precompile assets on the development machine application.js includes in the HTML as compressed and that way I have duplicated js code. Changing js doesn't make any effect because precompiled application.js interrupts this code.
That way my development process includes following steps:
Remove precompiled assets if I'm going to change js or css
Do some changes
Precompile assets
Upload assets to S3 by jammit-s3
Do commit and push my changes including assets to the git server
Deploy by capistrano
My questions are:
Is it possible to configure development environment don't include compressed application.js if I have it in public/assets directory?
Is it possible to configure production environment to work with empty public/assets directory? Assets will only be on the S3 server.
For question one I don't know a permanent solution other than running:
bundle exec rake assets:clean
before you switch back to development mode. I'd be interested to see if you can just ignore the assets in development without turning the entire assets pipeline off.
In production.rb there is an option for your second question:
# Enable serving of images, stylesheets, and JavaScripts from an asset server
config.action_controller.asset_host = "http://assets.example.com"
It should then ignore your assets directory since it relies on the remote host.
Hope that helps.
I resolved this problem by including assets dir in gitignore and exclude only one file - public/assets/manifest.yml and production server works correctly now, i.e. config.action_controller.asset_host = "http://assets.example.com" works. It requires only manifest.yml file
Right now, every time I am changing something in the assets, I have to delete the assets folder from the public directory and then run rake assets:precompile to take effect.
Is this something right or wrong so I should put it in a capistrano task to do it automatically?
For some reason, it doesn't compile automatically the assets in production and it throws errors if I don't do the above (or it doesn't take effect the changes if there is the files already). Is there something I should put in the environments/production.rb?
Also I don't understand what the following code in the production.rb does:
# Don't fallback to assets pipeline if a precompiled asset is missed
config.assets.compile = true
I tried false and true but I didn't understand the difference.
I'm a bit confused as at how it should work the workflow in production, if what I am doing is right and about the settings for the assets in production.
Capistrano has built-in support for precompiling assets during deployment. Just add this line to your deploy.rb file:
load "deploy/assets"
I prefer not to concatenate JavaScript files in development mode, but serve them as individual files. So I configured:
development.rb:
config.assets.compress = false
config.assets.debug = true
config.assets.compile = true
In my /app/assets/javascript directory I have:
reviews.js
reviews/
foo.js
bar.js
reviews.js:
//= require jquery
//= require jquery_ujs
//= require_tree ./reviews
I include the JavaScript using <%= javascript_include_tag "reviews" %> in my layout. The generated page correctly references the three scripts individually and reviews.js is essentially empty. So far so good.
Now when I precompile my assets for production using rake assets:precompile the three JavaScript files are concatenated into reviews.js. This is all fine for production but now, in development mode, the concatenated reviews.js is served in addition to the two individual files.
Of course, this leads to all kinds of nasty bugs when developing because now, the content of foo.js and bar.js is served twice, one of them in a potentially older version in reviews.js.
How can I make sure Rails doesn't use the precompiled assets in development mode?
In config/environments/development.rb set:
config.assets.prefix = "/assets_dev"
so that in development mode Rails will look there (but it will not find anything, as you will not compile assets in development (this is indeed what you are trying to do -- not compile assets)).
When precompiling for production, use
RAILS_ENV=production rake assets:precompile
so it compiles into the default assets folder, public/assets.
It sounds like you are precompiling locally. Because the files exist in the expected location they are being served by your dev server, and the requests are not going to Sprockets.
The only way to stop this is delete the compiled files.
Normally you do not need to compile locally. It is expected that in almost all cases the precompile task will be run during deployment of the app. There is a Capistrano recipe for this on the asset pipeline guide page.
If you do need to have those files locally committed to your repo you could use a branch to avoid the problem. Reserve your master branch for production code, and make a second branch for dev. Only compile and commit assets on master. When you switch to dev, they will be gone. Merge dev into master as required.
Edit: Make sure you force your browser to update (control + F5) or you may find the old assets used from the browser cache!
in config/environments/development.rb set:
config.serve_static_assets = false
and no files from /public will be served
I tried this and it worked. rake assets:precompile RAILS_ENV=production
I observed that the new version of assets pipeline does this when you run rake assets:precompile does rake assets:precompile:all