When deploying a Ruby 3.2.2, Rails 7.1.3 app to dokku I get this error very early in the build process:
!
! [!] There was an error parsing `Gemfile`: `windows` is not a valid platform. The available options are: [:ruby, :ruby_18, :ruby_19, :ruby_20, :ruby_21, :ruby_22, :ruby_23, :ruby_24, :ruby_25, :ruby_26, :mri, :mri_18, :mri_19, :mri_20, :mri_21, :mri_22, :mri_23, :mri_24, :mri_25, :mri_26, :rbx, :truffleruby, :jruby, :jruby_18, :jruby_19, :mswin, :mswin_18, :mswin_19, :mswin_20, :mswin_21, :mswin_22, :mswin_23, :mswin_24, :mswin_25, :mswin_26, :mswin64, :mswin64_19, :mswin64_20, :mswin64_21, :mswin64_22, :mswin64_23, :mswin64_24, :mswin64_25, :mswin64_26, :mingw, :mingw_18, :mingw_19, :mingw_20, :mingw_21, :mingw_22, :mingw_23, :mingw_24, :mingw_25, :mingw_26, :x64_mingw, :x64_mingw_20, :x64_mingw_21, :x64_mingw_22, :x64_mingw_23, :x64_mingw_24, :x64_mingw_25, :x64_mingw_26]. Bundler cannot continue.
!
! # from /tmp/build/Gemfile:39
! # -------------------------------------------
! # # Windows does not include zoneinfo files, so bundle the tzinfo-data gem
! > gem "tzinfo-data", platforms: %i[ windows jruby ]
! #
! # -------------------------------------------
when using dokku with heroku buildpacks you have a choice of a hand full of buildpacks. as of january 2024 the website lists the following runtime versions available:
In the question Ruby 3.2.2 was specified. This would lead to Ruby 3.2.3 and Rubygems 3.4.19 being chosen. Rubygems 3.4.19 comes with bundler 2.4.19Release Notes.
The Gemfile shown in the question contains :windows, which is not recognized by Bundler 2.4.19.
The solution is to revert to:
When you use these version in your development environment you will be able to deploy to dokku with current buildpacks.