Rails - why is /public/assets gitignored when I need this for static imaged-CodePudding

In my Rails (Rails 7) app, I have some small assets (a logo and a favicon), which I want to render in production as well as in development.

I put the assets in /app/assets/images.

Since setting # config.assets.compile = true is not recommended, i run RAILS_ENV=production bundle exec rake assets:precompile. It then builds a whole lot of files (it runs esbuild app/javascript/application.tsx since I have a typescript react app running in this rails app.) and puts them in /public/assets/. But this folder is .gitignored by default. Since the folder is approx 5.5 Mb I can see why. Now, heroku docs tell me to add /public/assets/ to git and then my assets should show, but why then is this directory gitignored by default?

Am I missing something? Should I just remove the dir from my .gitignore file?

Or could I just put the assets in the public folder directly? If so, how do I add an image referencing the public folder in an erb file?

CodePudding user response：

Thanks for the comments, I went with adding the assets to the public folder directly and this works fine. It would be nice though if Heroku would either support a way to generate the assets after deployment by default, or describe an option to do it like I did in their docs.

CodePudding user response：

The home for static assets is the /public folder. In a default Rails 7 app you will find some error pages (e.g. /public/404.html) and icons (e.g. /public/favicon.ico) already in that folder. Files in this folder will be available both directly, example.com/favicon.ico, and under the public path, example.com/public/favicon.ico. Serving public files can be disabled, see below.

To answer your sub-question, "how do I add an image referencing the public folder in an erb file?" you need to make sure you tell Rails it's an absolute path, not a relative one somewhere in the asset pipeline. This is done with a leading forward slash.

The following compares including a logo called logo.png when it's stored in app/assets/images vs /public

<%= image_tag "logo.png" %>
<!-- becomes <img src="/assets/logo-1f04fdc3ec379029cee88d56e008774df299be776f88e7a9fe5.png"> or similar -->


<%= image_tag "/logo.png" %>
<!-- note the leading slash. This becomes <img src="/logo.png"> -->

<img src="/logo.png">
<!-- or use plain HTML if you don't need/want to use the helper -->

You can also use sub-directories; /public/images/logo.png would be available at /images/logo.png (or image_tag "/images/logo.png").

The second paragraph of chapter 2 of The Asset Pipeline Rails Guide contians more information. It mentions that this functionality depends on whether config.public_file_server.enabled is set.

In Rails 7 that config defaults to ENV["RAILS_SERVE_STATIC_FILES"].present? in config/production.rb. If you're using Heroku you can check this variable with heroku config:get RAILS_SERVE_STATIC_FILES.

The guide also has more information on how to adjust all this behaviour to have these files served by your upstream web server (e.g. nginx) or from a CDN.