Can I force Heroku to compile the assets? - ruby-on-rails

I used to develop a project on my own and now I have got some others to help in the project. It's developed with Ruby on Rails and we have a staging server on Heroku. Beforehand the deployment workflow is to precompile the assets in local machine then push the code to heroku. It works well when I am on my own.
Now I am working with a Front-end engineer. The problem is we are working in different location so it is difficult to setup his computer the same as mine. As a result, he will not be able to precompile the code before pushing to heroku.
Of course I can do it for him but would be better if he can just submit the code to the staging server and let Heroku to precompile it. I think Heroku detect if the manifest file is available to determine if it needs to precompile. Is there a way to force Heroku to recompile the assets?
I have tried: heroku run rake assets:clean then heroku run rake assets:precompile but no luck...

Heroku's servers use a read-only file system. This is how they make it easy for you to spin up more dynos, among other things.
Compiling Rails assets means taking the source files and compiling a new file, i.e. writing a file to the file system. Since this can't happen on a read-only file system, you have to precompile first. Even if you did manage to compile assets on Heroku, by writing to the /tmp directory, at the end of the day when Heroku reboots dynos, your new files will be gone because they weren't checked into the repo as they would've been if you had precompiled them locally, committed them, and then pushed to Heroku.
Any workaround I can imagine would be more complicated than helping your front end dev setup Rails and bundle installing the gems needed to precompile before pushing.

Related

Correct procedure to change location of asset compilation with Heroku

I want to change from having Heroku pre-compile the assets to pre-compiling them on development and pushing them to Heroku. I understand the basic procedure is
RAILS_ENV=production bundle exec rake assets:precompile
git add .
git commit -m 'Add precompiled Assets'
git push production master
However, this wipes out any existing assets on heroku. For instance, images referenced in old emails are wiped out. Is there a way to do this and provide a continuity with legacy assets?
Based on some help from Heroku support and the comments from Schneems below, here is the non-answer I came to.
Unless you understand the intricacies of managing your assets with sprockets, precompile on heroku rather than locally.
Whether you precompile locally or heroku, use a CDN and set far future expire dates on your assets.
Use the latest version of sprockets (3.7.1 as the time of writing this post).
If you precompile locally, be aware that sprockets does keep the last three copies of the assets around, and keep in mind it is up to you to keep your assets consistent with the last release.
There are many edge cases, so there is no such thing as a simple answer that suits the stack overflow format.
So in summary, unless you are highly knowledgeable or courageous, do not precompile locally.
And finally, use a CDN.

SASS: After every change have to reboot my server

Using: rails4 app
Command: For Connecting and Rebooting in order to see the change.
rake assets:precompile
and
control + c
rails s
Is it normal!! Because, sometime I have to do a lot of change and I don't want to reboot the rails server 2000 times per hour.
It's development machine.
Suggestions would be appreciated.
I'm not sure why you're precompiling while still making changes to your SASS.
During development, if making frequent changes to SASS, I'll have cleaned my assets out and the server will pick up and compile these changes as I make them.
rake assets:precompile
is only used when I push to production
There is some guidance here: http://guides.rubyonrails.org/asset_pipeline.html#local-precompilation on why you might want to precompile locally, but I can't speak for your own projects.
I had a lot of headaches when trying to edit js files and refresh them while my assets were precompiled and they all went away went I ditched it in dev.
I solve it with this command
rake assets:clobber
Thanks anyway.

Amazon S3 for static assets with Rails

I followed the tutorial from asset_sync gem.
It looks ok, but I still don't understand something.
I'll have to run rake assets:precompile every time I want to update the assets, right? But if I wan't to run it only local, without sync? If I have to run it locally, why I have to put a lot of environment variables in heroku relating to S3?
It looks to me, looking at logs, that rails somehow get the sass files instead of compiled CSS files (and also throw some error because of that). How can I fix that?
github link

rake assets precompile failed

When I run bundle exec rake assets:precompile --trace, my precompilation fails but I cannot see any specific reason for it.
See this pastebin for my output: http://pastebin.com/zggZyPyM
Precompiling assets takes a lot of memory. ~=400mb in my case. It might be possible that OS is killing of the process due to excessive memory usage. You can check the syslog to verify if that is the case.
You can increase the memory of your server to avoid the situation. If that is not possible, I would suggest that you precompile assets on your local system, commit them to the repo and deploy to the server. That way you wouldn't have to compile assets on your server. However you might want to look into ways to delete the previously generated assets somehow and also automate the process.
, but issue was resolvedI tried installing node.js first. And then, ran the following command bundle exec rake assets:precompile. Only then I didn't notice the error.
Initially, I thought it was because of low memory too. Cleaned almost all running applications, but couldn't find a solution. Plus, I opened Ruby as administrator. Not sure if that helped too, but issue was resolved.
This issue can also be resolved by using a node.js JS runtime to precompile assets as it apparently has a lower memory footprint. For Ubunutu 14.04 I needed to run apt-get install nodejs, then replace the default js runtime in the Gemfile with gem 'node', run bundleand finally rerun the precompile. I would caution against precompiling in another location as you may forget to do this after a css or js change, leading to errors.

Rails 3.1 on heroku ckeditor

I have a big problem with the ckeditor "3.7.0.rc2" gem.
In development it works great with s3 a backend for uploading.
But on heroku it does not work.
The problem is that the ckeditor/vendor/skins/(kama) or (office2003) or (v2) /editor.css files contains an error that makes the sass compiler scream. The error like this "filter:;", since there is no value it does not work.
There is no point in change the files locally, because heroku downloads the gem as I deploy.
I have tried to package the gem locally and make my own git fork and install it for there. But, then the
RAILS_ENV=production bundle exec rake assets:precompile
command precompiles all files in the ckeditor folders and always ends in
rake aborted! Permission denied
When I precompile with the "3.7.0.rc2" gem installed, some ckeditor js files are precompiled but not all.
How can I get around this problem?
When you fork ckeditor gem and use the forked git path in Gemfile heroku will pull the sources of ckeditor from your forked git repo instead of the gem. This should fix the issue.
Other thing that you could try is precompile the assets in your development machine and push the assets to heroku. This will make sure that heroku will not precompile those assets. More info is available at http://devcenter.heroku.com/articles/rails31_heroku_cedar. This will run only on cedar stack
The solution was to fork the git repo, delete all unnecesarry and correct the errors. js files. Then the precompiling worked and now the app is running on heroku.
Here's a link to my fork https://github.com/andreaslyngstad/ckeditor
It worked in my project, but I have deleted js files that I did not use, so if you are using some of them, this is not for you.

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