User:Toshio/RubyPackagingDraft

This page is a draft only
It is still under construction and content may change. Do not rely on the information on this page.

Different guidelines for older Fedora and RHEL
In RHEL 4, 5, and 6 and Fedora before Fedora 16, a ruby version that does not have all the features needed to support these guidelines exists. If you're packaging for those distributions you should follow the old ruby guidelines instead.

There are three basic categories of ruby packages: ruby gems, non-gem ruby packages, and applications written in ruby. These guidelines contain sections common to all of these as well as sections which apply to each one individually. Be sure to read all the guidelines relevant to the type of ruby package you are building.

Ruby ABI

Each Ruby package must indicate the Ruby ABI version it depends on with a line like

Requires: ruby(abi) = 1.9.1

Naming Guidelines

• Packages that contain Ruby Gems must be called rubygem-%{gem_name}.

• The name of a ruby extension/library package must be of the form ruby-UPSTREAM. If the upstream name UPSTREAM contains ruby, that should be dropped from the name. For example, the SQLite database driver for ruby is called sqlite3-ruby. The corresponding Fedora package should be called ruby-sqlite3, and not ruby-sqlite3-ruby.

• Application packages that mainly provide user-level tools that happen to be written in Ruby must follow the general NamingGuidelines instead.

Macros

Interpreter independence
Related to the below text about interpreter independence. Move vendorlib/vendorarch to a non-MRI specific location

Non-gem ruby packages and ruby gem packages install to certain standard locations. The ruby-devel and rubygems-devel packages contain macros useful for the respective package types.

Macro	Expanded path	Usage
From ruby-devel; intended for non-gem packages
%{ruby_vendorarchdir}	/usr/lib{64}/ruby/vendor_ruby	Place for architecture specific (e.g. *.so) files.
%{ruby_vendorlibdir}	/usr/share/ruby/vendor_ruby	Place for architecture independent (e.g. *.rb) files.
%{ruby_sitearchdir}	/usr/local/lib{64}/ruby/site_ruby	Place for local architecture specific (e.g. *.so) files.
%{ruby_sitelibdir}	/usr/local/share/ruby/site_ruby	Place for local architecture independent (e.g. *.rb) files.
From rubygems-devel; intended for gem packages
%{gem_dir}	/usr/share/gems	Top directory for the Gem structure.
%{gem_instdir}	%{gem_dir}/gems/%{gem_name}-%{version}	Directory with the actual content of the Gem.
%{gem_libdir}	%{gem_instdir}/lib	The lib folder of the Gem.
%{gem_cache}	%{gem_dir}/cache/%{gem_name}-%{version}.gem	The cached Gem.
%{gem_spec}	%{gem_dir}/specifications/%{gem_name}-%{version}.gemspec	The Gem specification file.
%{gem_docdir}	%{gem_dir}/doc/%{gem_name}-%{version}	The rdoc documentation of the Gem.
%{gem_extdir}	%{_libdir}/gems/exts/%{gem_name}-%{version}	The directory for binary Gem extensions.

Dependencies

Due to having multiple types of libraries (gems and non-gems) there are two ways to specify dependencies.

Confirm change: rubygems to provide ruby()
Since rubygems now work with plain require the distinction between ruby() and rubygem() doesn't seem as necessary. I've reworked the requires and provides to tak this into account. Someone from ruby sig should confirm that this seems sensible.

Requires

If your package uses gem 'rubylibrary' or you're packaging a ruby gem that depends on the library in its .gemspec (See the section on building gems for more information) you Must use Requires: rubygem(rubylibrary) so the rpm will pull in the correct ruby library.

If your package just uses require 'rubylibrary' it's always fine to use Requires: ruby(rubylibrary). If you know that the ruby library is provided as a gem despite using require 'rubylibrary' you may use Requires: rubygem(rubylibrary) instead but this is not required as it forces packagers to know unnecessary details of how another ruby package has been created.

When packaging rubygems the gem itself carries some dependency information in the "gem specification". That specification may contain precise versions of dependent gems. If Fedora has packaged a different version of the gem you may have to adjust the .gemspec to work with the Fedora version of the package (see the section on building gems for more information).

Please ensure that the package works properly with the dependencies specified in the rpm spec file.

Provides

Non-gem ruby libraries Must indicate what they provide with Provides: ruby(RUBYLIBRARY) = VERSION. The string RUBYLIBRARY Must be the same as what is used in the require statement in a Ruby script that uses the library. The VERSION should be the upstream version of the library, as long as upstream follows a sane versioning scheme. For example, a Ruby script using the SQLite database driver will include it with require 'sqlite3'. The specfile for the corresponding Fedora package must contain a line Provides: ruby(sqlite3) = 1.1.0, assuming the package contains version 1.1.0 of the library.

Gem packages must have two provides:

Provides: ruby(RUBYLIBRARY) = VERSION
Provides: rubygem(%{gem_name}) = %{version}

This allows people who are packaging something that requires the gem to use either form of the dependency to get the proper package. Since their package may only have a require 'rubylibrary' in the code, there's no reason for them to have to figure out whether we've packaged it as a gem or a non-gem library. The rubygem(%{gem_name}) form of the dependency allows packages which depend on having the gem metadata to specify that the Fedora package must be packaging a gem form of the library, not a non-gem form of the library.

Libraries

These guidelines only apply to Ruby packages whose main purpose is providing a Ruby library; packages that mainly provide user-level tools that happen to be written in Ruby must follow the ruby applications guidelines instead.

Move text about interpreter independence to here
In Fedora we strive to make rubylibraries run on all versions of the interpreter (ruby, jruby, etc) that we ship. We may carry patches so that the libraries run on all versions of the interpreter and we install them to interpreter neutral locations.

RubyGems

RubyGems are Ruby's own packaging format. Gems contain a lot of the same metadata that RPM's need, making fairly smooth interoperation between RPM and Gems possible. This guideline ensures that Gems are packaged as RPM's in a way that ensures (1) that such RPM's fit cleanly with the rest of the distribution and (2) make it possible for the end user to satisfy dependencies of a Gem by installing the appropriate RPM-packaged Gem.

See above
About moving the next bit of text to the overall libraries portion.

In Fedora we strive to make rubygems run on all versions of the interpreter (ruby, jruby, etc) that we ship. We may carry patches so that gems run on all versions of the interpreter and we install them to interpreter neutral locations.

Both RPM's and Gems use similar terminology --- there are specfiles, package names, dependencies etc. for both. To keep confusion to a minimum, terms relating to Gem concepts will be explicitly refereed to with the word 'Gem' prefixed, eg 'Gem specification' (.gemspec). An unqualified 'package' in the following always means an RPM.

• Spec files must contain a definition of %{gem_name}, which is the name from the Gem's specification.
• The Source of the package must be the full URL to the released Gem archive; the version of the package must be the Gem's version.
• The package must BuildRequires: rubygems-devel to pull in the macros needed to build.

Building gems

Since gems aren't a standard archive format that rpm knows about and they encapsulate both an archive format and information to build the ruby library building an rpm from a gem looks a little different from other rpms.

A sample spec for building gems would look like this:

%prep
%setup -q -T -n  %{gem_name}-%{version}
gem unpack %{SOURCE0}
pushd %{gem_name}-%{version}

gem spec %{SOURCE0} -l --ruby > %{gem_name}.gemspec
# Modify the gemspec if necessary with a patch or sed
# Also apply patches to code if necessary
%patch0 -p1

popd

%build
mkdir -p ./%{gem_dir}
mkdir -p ./%{_bindir}

# Create the gem as gem install only works on a gem file
gem build %{gem_name}.gemspec
export CONFIGURE_ARGS="--with-cflags='%{optflags}'"
# gem install compiles any C extensions and installs into a directory
gem install -V \
        --local \
        --install-dir ./%{gem_dir} \
        --bindir .%{_bindir} \
        --force \
        --rdoc
        ../%{gem_name}-%{version}/%{gem_name}-%{version}.gem

%install
mkdir -p %{buildroot}%{gem_dir}
cp -a .%{gem_dir}/* %{buildroot}%{gem_dir}/

# If there were programs installed:
mkdir -p %{buildroot}%{_bindir}
cp -a .%{_bindir}/* %{buildroot}%{_bindir}

# If there are C extensions, mv them to the extdir.
# $REQUIRE_PATHS is taken from the first value of the require_paths field in
# the gemspec file.  It will typically be either "lib" or "ext".  For instance:
#  s.require_paths = ["lib"] 
mkdir -p %{buildroot}%{gem_extdir}/$REQUIRE_PATHS
mv %{buildroot}%{gem_instdir}/$REQUIRE_PATHS/shared_object.so %{buildroot}%{gem_extdir}/$REQUIRE_PATHS/

%prep

In the %prep section we first use %setup -n %{gem_name}-%{version} to tell rpm what the directory the gem will unpack into. We use the -T flag to tell %setup not to try unpacking the source on its own. Then we explicitly use gem unpack to extract the source from the gem and switch into the directory. This is equivalent to the steps that %setup would take if gem was a recognized archive format.

We then run gem spec to output the metadata from the gem into a file. This .gemspec file will be used to rebuild the gem later. If we need to modify the .gemspec (for instance, if the version of dependencies is wrong for Fedora or the .gemspec is using old, no longer supported fields) we would do it here. Patches to the code itself can also be done here.

%build

Next we build the gem. The first step is to create directories in which to temporarily install the built sources. We do this because the gem install command both builds and installs the code in one step so we need to have a temporary directory to place the built sources before installing them in %install. Because gem install only operates on gem archives, we next recreate the gem with gem build. The gem file that is created can then be used by gem install to build and install the code into the temporary directory we created earlier.

%install

Here we actually install into the %{buildroot}. We create the directories that we need and then copy what was installed into the temporary directories into the %{buildroot} hierarchy. Finally, if this ruby gem creates shared objects the shared objects are moved into the arch specific %{gem_extdir} path.

Packaging for Gem and non-Gem use

Packaging for non-Gem use is no longer needed
Originally, rubygem modules were not placed in ruby's library path, so we packaged rubygems for use with both gems and non-gems. The current rubygem module adds all gems to the ruby library path when it is require'd. So, packagers must not create non-Gem subpackages of rubygems for new packages. Since the majority of Ruby packages in Fedora are now packaged as installed gems, you may need to use require('rubygem') as early in the program as possible to ensure that these ruby components are properly found. Packages for ruby gems that currently create a non-gem subpackage should be adapted to stop shipping the non-gem subpackage (with a proper Obsoletes and Provides in the main rubygem package).

Tips for Packagers

Gems carry a lot of metadata; gem2rpm is a tool to generate an initial specfile and/or source RPM from a Gem. The generated specfile still needs some hand-editing, but conforms to 90% with this guideline.

Non-Gem Packages

I haven't gotten to reviewing what may need changing from here on

Non-Gem Ruby packages must require ruby-devel package at build time with a BuildRequires: ruby-devel, and may indicate the minimal ruby version they need for building.

Build Architecture and File Placement

The following only affects the files that the package installs into %{_libdir}/ruby/vendor_ruby (architecture specific) and %{_datadir}/ruby/vendor_ruby (architecture independent), i.e. Ruby library files. All other files in a Ruby package must adhere to the general Fedora Extras packaging conventions.

Site versus Vendor
Previously, %{ruby_sitelibdir} and %{ruby_sitearchdir} were used. However, as they are meant only for local installations, please use %{ruby_vendorlibdir} and %{ruby_vendorarchdir} instead.

Pure Ruby packages

Pure Ruby packages must be built as noarch packages.

The Ruby library files in a pure Ruby package must be placed into %{ruby_vendorlibdir} (or its proper subdirectory). The specfile must use this macro.

Ruby packages with binary content/shared libraries

For packages with binary content, e.g., database drivers or any other Ruby bindings to C libraries, the package must be architecture specific.

The binary files in a Ruby package with binary content must be placed into %{ruby_vendorarchdir} (or its proper subdirectory). The Ruby files in such a package should be placed into %{ruby_vendorlibdir}. The specfile must use these macros.

For packages which create C shared libraries using extconf.rb

export CONFIGURE_ARGS="--with-cflags='%{optflags}'"

should be used to pass CFLAGS to Makefile correctly. Also, to place the files into the correct folders during build, pass --vendor to extconf.rb like this:

extconf.rb --vendor

Applications

By applications we mean:

• programmes that provide user-level tools or
• web applications, typically built using Rails, Sinatra or similar frameworks.

The RPM packages must obey FHS rules, it means that they should be installed into %{_datadir}. Following macro can help you:

%global app_root %{_datadir}/%{name}

These packages typically have no "Provides" section, since no other libraries or applications depend on them.

A good example is the initial specfile of deltacloud-core package (shortened here):

%global app_root %{_datadir}/%{name}

Summary: Deltacloud REST API
Name: deltacloud-core
Version: 0.3.0
Release: 3%{?dist}
Group: Development/Languages
License: ASL 2.0 and MIT
URL: http://incubator.apache.org/deltacloud
Source0: http://gems.rubyforge.org/gems/%{name}-%{version}.gem
Requires: rubygem(haml)
#...
Requires(post):   chkconfig
#...
BuildRequires: rubygem(haml)
#...
BuildArch: noarch

%description
The Deltacloud API is built as a service-based REST API.
You do not directly link a Deltacloud library into your program to use it.
Instead, a client speaks the Deltacloud API over HTTP to a server
which implements the REST interface.

%package doc
Summary: Documentation for %{name}
Group: Documentation
Requires:%{name} = %{version}-%{release}

%description doc
Documentation for %{name}

%prep
%setup -q -c -T 
gem unpack -V --target=%{_builddir} %{SOURCE0}

%build

%install
mkdir -p %{buildroot}%{app_root}
mkdir -p %{buildroot}%{_initddir}
mkdir -p %{buildroot}%{_bindir}
cp -r %{_builddir}/%{name}-%{version}/* %{buildroot}%{app_root}
mv %{buildroot}%{app_root}/support/fedora/%{name} %{buildroot}%{_initddir}
find %{buildroot}%{app_root}/lib -type f | xargs chmod -x
chmod 0755 %{buildroot}%{_initddir}/%{name}
chmod 0755 %{buildroot}%{app_root}/bin/deltacloudd
rm -rf %{buildroot}%{app_root}/support
rdoc --op %{buildroot}%{_defaultdocdir}/%{name}

%post
# This adds the proper /etc/rc*.d links for the script
/sbin/chkconfig --add %{name}

%files
%{_initddir}/%{name}
%{_bindir}/deltacloudd
%dir %{app_root}/
%{app_root}/bin
#...

%files doc
%{_defaultdocdir}/%{name}
%{app_root}/tests
%{app_root}/%{name}.gemspec
%{app_root}/Rakefile

%changelog
#...

Note, that although the source is a RubyGem, gem unpack is used instead of common gem install to extract the application and library files. These are then placed under %{_datadir}/%{name}, %{_bindir}, etc. to follow FHS and general packaging guidelines. If additional Fedora specific files (systemd .service files, configurations) are required, they should be

• added via another %SOURCE tags

Source1: deltacloudd-fedora

• placed into appropriate locations during %install stage

install -m 0755 %{SOURCE1} %{buildroot}%{_bindir}/deltacloudd

Running test suite

If there is test suite available for the package (even separately, for example not included in the Gem, but available in the upstream repository), you should run it. The test suite is the only automated tool which could assure basic functionality of package. This is helpful when mass rebuild is required for example. You could skip test suite execution in case when not all build dependencies are met, but this must be documented in specfile. Nevertheless, the build dependencies should be imported into Fedora as soon as possible.

The tests should not be run using Rake - Rake almost always draws in some unnecessary dependencies like hoe or gemcutter.

Testing frameworks usage

Ruby community provides and supports various testing frameworks. Following paragraphs demonstrates how the test suite can be executed. Please note that the list is not exhaustive.

MiniTest

MiniTest is default testing framework shipped together with Ruby, however unbundled in Fedora (you must use BuildRequires: rubygem(minitest)). To run the tests using MiniTest, you can usually use something like

testrb -Ilib test

Test::UNIT

To run the tests using Test::Unit (you must use BuildRequires: rubygem(test-unit)), you can usually use something like

testrb2 -Ilib test

Please note that test suite which runs using Test::UNIT can be typically executed also by MiniTest. In that case, please prefer MiniTest.

RSpec

To run the tests using RSpec >= 2 (you must use BuildRequires: rubygem(rspec-core)), you can usually use something like

rspec -Ilib spec

Test suite not included in package

Typical way of getting the tests separately from upstream follows - lets suppose you're packaging rubygem-delorean, version 1.2.0, which is hosted on Git. Tests are not included in the Gem itself, so you need to get them and adjust the specfile accordingly:

# git clone https://github.com/bebanjo/delorean.git && cd delorean
# git checkout v1.2.0
# tar -czf rubygem-delorean-1.2.0-specs.tgz spec/
Source1: %{name}-%{version}-specs.tgz

# ...

%check
pushd .%{gem_instdir}
tar xzf %{SOURCE1}
popd

# ...

• Make sure to include the version of the tests in the source name, so that when updating to new version, rpmbuild will fail because it won't find the proper %SOURCE1 (and this will remind you to update the tests, too).
• Add the commands you used to get the tests into the specfile as comments. This will make it a lot easier the next time you will need to get them.
• Run the tests as you normally would.