Ruby Gem package guidelines

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Template:Package Guidelines

Writing PKGBUILDs for software written in Ruby.

Package naming

For libraries, use ruby-$gemname. For applications, use the program name. In either case, the name should be entirely lowercase.

Always use ruby- prefix even if $gemname already starts with word ruby. It is needed to avoid future name clashes in case if a gem with shorter name appear. It also makes names more easily parseble by tools (think about PKGBUILD generators/version or dependency checkers, etc...). Examples: ruby-ruby-protocol-buffersAUR.

Versioned packages

If you need to add a versioned package then use ruby-$gemname-$version, e.g. ruby-builder-3.2.1. So rubygem dependency builder=3.2.1 will turn into ruby-builder-3.2.1 Arch package.

In case if you need to resolve "approximately greater" dependency ~> then package should use version without the last part, e.g. rubygem dependency builder~>3.2.1 will turn into ruby-builder-3.2. An exception for this rule is when "approximately greater" dependency matches the latest version of the gem - in this case avoid introducing a new versioned package and use just ruby-$gemname instead (the HEAD version).

Another problem with versioned packages is that it can conflict with other versions, e.g. because the packages install the same files in /usr/bin. One solution for this problem is that versioned packages should not install such files - only HEAD version package can do this.

Examples

For examples, please see ruby-rethinkdbAUR ruby-json_pureAUR ruby-hpricotAUR.

Notes

Add --verbose to gem arguments to receive additional information in case of troubles.

Note: Usage of --no-user-install gem argument is mandatory since latest Ruby versions (See FS#28681 for details).

Gotchas

Package contains reference to $pkgdir

Sometimes when you build the package you can see following warning WARNING: Package contains reference to $pkgdir. Some packed files contain absolute path of directory where you built the package. To find these files run cd pkg && grep -R "$(pwd)" . Most likely the reason will be hardcoded path in .../ext/Makefile.

Note: folder ext contains native extension code usually written in C. During the package installation rubygems generates a Makefile using mkmf library. Then make is called, it compiles a shared library and copies one to lib gem directory.

After gem install is over the Makefile is not needed anymore. In fact none of the files in ext is needed and it can be completely removed by adding rm -rf "$pkgdir/$_gemdir/gems/$_gemname-$pkgver/ext" to package() function.

Example PKGBUILD

An example PKGBUILD can be found at /usr/share/pacman/PKGBUILD-rubygem.proto, which is in the abs package.

Automation

The gem installation can be automated completely with the tool pacgemAUR which creates a temporary PKGBUILD, calls makepkg and namcap. The resulting package is then installed with sudo pacman.

There is also gem2archAUR tools which aid in automating the process of creating a ruby gem PKGBUILD. Make sure to manually check the PKGBUILD after generation.