Rails 4 Asset Pipeline: Asset missing fingerprint in asset_path from js - ruby-on-rails

I am deploying a Rails 4.0 application which includes HTML partial templates as assets for our front-end javascript framework. Although these templates are part of the asset pipeline and are properly precompiled, when I call asset_path from embedded ruby in our js files, it returns the path to our templates without the fingerprint.
I am quite certain that this is purely a Asset Pipeline question, but to give you a complete sense of our tech stack: We use Rails 4.0, Ruby 2.1, AngularJS for our front-end MVC framework, and AssetSync to synchronize our assets between Rails and our CDN.
An example of where this occurs (in a file included in app/assets/application.js.erb:
$routeProvider
.when('/', {
templateUrl: "<%= asset_path 'home.html' %>",
controller: "HomeController"
});
This works great locally, but as soon as config.assets.digest = true in production, the call to asset_path does not properly factor in the fingerprint. The templates are in the app/assets directory within a new subdirectory templates. So in the above example, the home.html asset is at app/assets/templates/home.html. Our javascript has itself been precompiled at that point, so I'm thinking that it might be an issue of which order the assets are precompiled in.
I've noticed a few issues on the Rails Github (1, 2, 3) and a couple of SO posts about fingerprints not being set properly (1, 2), but can't find anything about them not being included at all...
Any help or ideas that you can provide would be much appreciated.
Edit 4/15: forgot to include that the extensions on my application javascript file DOES include .erb (app/assets/application.js.erb). Thanks Alex for catching that. I've updated it above.
Also, following instructions in this article on Heroku, I confirmed that running puts helper.asset_path("home.html") from within a Rails console running in production prints a properly fingerprinted URL for that asset.

This appears to be an issue with the AssetSync gem. I removed it, reconfigured the app so that Rails serves the assets, and the fingerprinting works fine.
If anyone else finds this question and is running into the same issue, I would recommend against using AssetSync. According to Heroku:
Many developers make use of Amazon’s S3 service for serving static assets that
have been uploaded previously, either manually or by some form of build process.
Whilst this works, this is not recommended as S3 was designed as a file storage
service and not for optimal delivery of files under load. Therefore, serving
static assets from S3 is not recommended.
Amazon CloudFront is the preferred method of serving assets through a CDN, and is very easy to configure with a Rails app that serves its own static assets, accomplishing the same goals as AssetSync.

I'm pretty new to this stuff, but to get the asset_path to work, don't you need a .erb on the end of that file?
Check out the bottom of this article for more info:
https://devcenter.heroku.com/articles/rails-4-asset-pipeline
If it works in development, that may not help. There is a helpful section on debugging at the bottom of the article though.
Update
Here's another article that could help:
https://medium.com/self-directed-learning/9ba1f595102a
Flipping on this configuration in Heroku made some of my asset pipeline problems go away:
heroku labs:enable user-env-compile -a yourapp
Hope this helps!
Alex

Related

Rails 4 Heroku Assets not loading, though in heroku asset pipeline

I have a problem with certain assets on heroku. (local environment is working fine)
The assets are in the pipeline. If I execute in the heroku rails console:
helper.asset_path("typicons.woff")
helper.asset_path("backgrounds/1.jpg")
I get the following response:
/assets/typicons-c2430aad2b6a33948dc064cfaee8ad65ff9e3ca439834f3aaa84abec3d10dea8.woff
/assets/backgrounds/1-c2098ff7e7fbb89b2d18e9cd9089f712f2b837265d1d2e4182c36c23392760c6.jpg
So I assume that the assets are in the heroku asset pipeline. As well by opening the url directly with the digest in it, I receive the file.
However if I try to reference the files in css or javascript like this:
$('.top-content').backstretch("/assets/backgrounds/1.jpg");
The file does not load. As well opening /assets/backgrounds/1.jpg directly does not work. Referencing assets from .rb or .erb files works.
Please can someone tell me, what kind of config I have to change, so the URLs for assets work as well without the digest?
Thank you!
Assuming you are using a fairly standard asset pipeline setup, this passage from the Rails Guides should help:
If you add an erb extension to a JavaScript asset, making it something such as application.js.erb, you can then use the asset_path helper in your JavaScript code:
-- http://guides.rubyonrails.org/asset_pipeline.html (section 2.3.3)
In your example, add the erb extension to your JS file and then change the line to
$('.top-content').backstretch(<%= asset_path("backgrounds/1.jpg") %>);
The problem is that Rails 4 does not support non-digested assets at all.(For whatever reason)
Here is a more thorough explanation on the issue: Non Digested Asset Names in Rails 4
My personal workaround was to add a public asset folder to my app:
public/assets/static/
and upload the assets required there. Since it was only about fonts and background images, which do not change often, it does not seem to be a problem. In the link above there are several other solutions proposed.

Using ExtJS along with the Rails Assets Pipeline

For an application built on top of Rails (3.1.8) with ExtJS 4.1, we have the following files layout:
app/
assets/
javascript/
application.coffee
WID/
Lots of coffeescript files and folders.
public/
extjs/
ext-all-debug-w-comments.js and the whole ExtJS framework.
Our application heavily relies on the Ext loader (Ext.Require) to dynamically load files based on users rights / allowed modules. We would like to keep this functionality as much as possible, so only the required files are requested from the server. Bandwidth isn't really an issue, as the application is intranet-based (On a LAN).
In development environment, everything runs smooth. In production environment however, we are having problems. It looks like either the "rake assets:precompile" task is concatenating all files into an application.js file, and then when accessing our application the Ext loader complains that it can't find individual files (Because assets/WID/.../file.js isn't being served by the rails server).
So right now, i'm not sure what would be the best move to take... Is there anyone able to help us with a successful Rails + ExtJS production setup taking the best from the assets pipeline?
Thank you,
Pierre.
I think you should move your javascripts (and generally all the assets) from your public into vendor/assets/javascripts when you are in development environment. This way the asset-pipeline gets in charge.
EDIT: You may consider reverting your manifest file to application.js, not application.coffee. Generally it is a bad idea to rename these special files : application.css and application.js .In case you have some coffescript to add , just create a new file and place it in an asset directory.

Page caching trick on Heroku?

I am moving a rails app to Heroku.
Heroku doesn't seem to support page caching.
So I generated cached pages on my development machine and checked them in to Heroku.
For example, /about_us generates public/about_us.html.
But when I call /about_us, public/about_us.html doesn't seem to be called.
Should my trick work?
Thanks.
Sam
In Rails 3, you'll be using the assets pipeline, so your assets--about_us.html--will be precompiled and put into a folder, WITHIN your public folder. Usually, this file will not be located at 'public/about_us.html'.
With your assets now precompiled, they'll be statically available and appended with an id, that will uniquely identify this asset until it is changed. With the unique signature, caching will occur on both Heroku's (last I checked) as well as within browsers.
Basically, the asset pipeline is doing this already for you.

Rails 3 automatic asset deployment to Amazon CloudFront?

Is there a gem or method available in Rails 3.1 that can upload assets to amazon cloud front automatically and use those instead of serving locally hosted ones? I guess it's easy to upload compiled assets manually and then change the rails app config to use that asset host, but when an asset is modified, the uploads to cloud front would need to be done manually again. Any good ways out there for this?
Definitely check out asset_sync on github. Or our Heroku dev centre article on Using a CDN asset Host with Rails 3.1 on Heroku.
There is quite a big performance improvement in using asset_sync vs a CDN custom origin, letting your application lazily compile assets in production or serving them precompiled directly off your app servers. However I would say that. I wrote it.
With asset_sync and S3 you can precompile assets meaning all the assets are there ready to be served on the asset host / CDN immediately
You can only require the :assets bundle in application.rb on precompile, saving memory in production
Your app servers are NEVER hit for asset requests. You can spend expensive compute time on, you know. Computing.
Best practice HTTP cache headers are all set by default
You can enable automatic gzip compression with one extra config
If you use Cloudfronts “Custom origin” option you do not need to upload anything, Cloudfront will fetch the assets from your server when needed. For details of setting this up see:
http://blog.ertesvag.no/post/10720082458
Take a look at https://github.com/rumblelabs/asset_sync - we're using it just to S3 but I guess the CloudFront part is pretty easy once the assets are on S3.
It's ends up being a rake task that you just add to execute in your deployment process.
another option would be https://github.com/moocode/asset_id, the readme has an example to use it with cloudfront.
It should work with rails 3.1 but I have only used it on 3.0.x.
Ss John said all solutions would end up being a rake task + a bit of logic to change the asset path in rails.

Rails 3.1 Assets are being fingerprinted in production but rendered HTML is not

Everything works great in Development. And app deploys as normal with Capistrano. Assets (javascript & css) appear to be fully pre-compiled and each, along with images, are given a "fingerprint". Problem is when using image_tag("image-name.png") in my view the html it creates in production doesn't include the 'fingerprint'.
The rendered HTML we get in production:
<img alt="Image-name" src="/assets/image-name.png" />
instead of, what I would expect, should be:
<img alt="Image-name" src="/assets/image-name-b89cae2830c2901f844c353b3f3942fe.png" />
So which of Rails 3.1's myriad config options did we botch?
Edit
The troublesome images appear to be those included in a 3rd-party Colorbox image viewing tool we use. Rails 3.1 is fingerprinting its assets (border.png, etc.) but, clearly, the source code for this javascript library doesn't use helpers like image_tag. So in production it is still looking for images named /assets/colorbox/border.png. Currently images are in /vendor/assets/images and work fine in Development. Is there a way to prevent just these images from being "fingerprinted"?
Well, here's how I hacked the 3rd-party files to make things work:
The offending images were in files like vendor/assets/stylesheets/colorbox.css. I first changed the extension of the files to .scss then I changed each url(colorbox/image.png) to image_url("color box/image.png") and now everything is peachy. Assets are served normally in development and fingerprinted in production.
Still like to see the "proper" way to add 3rd-party (vendor) javascript libraries & css to a Rails 3.1 app. Rails team must have anticipate a drop-in solution that doesn't require editing?!? So, please, feel free to offer up other solutions.
Aside: where I previously had manually configured my Capistrano recipe with:
run "cd #{release_path}; RAILS_ENV=production bundle exec rake assets:precompile"
…and its accompanying after deploy:update_code …. I have now removed those lines and instead added load 'deploy/assets to my Capfile. I don't think this makes any difference in the above problem but I wanted to document it anyway as adding your own recipe for pipeline precompiling is no longer necessary in Capistrano 2.8 as it was in the 3.1rc days.

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