SBR600 Mock and Koji Lab

Purpose

To use and become familiar with the mock and koji tools.

Mock is used to test that the BuildRequires for a package are complete and accurate, by creating a bare-bones chroot environment containing only the basic build packages plus any packages indicated by BuildRequires lines in the spec file.

Koji is a client-server system which allows you to queue builds within the Fedora build farm. This permits you to test whether your package builds on multiple different architectures, which is especially useful when you don't otherwise have access to the machines of each architecture. For example, if you are working on a 32-bit PC, you won't be able to directly test builds on a 64-bit PC architecture (x86_64), nor non-PC architectures such as ARM, MIPS, PA-Risc, IA64, S390, Sparc, and PowerPC.

Background Resources

• Fedora Wiki - Using Mock to test package builds
• Fedora Wiki - Using Koji

Required Resources

Before starting this lab, you will need:

1. A Fedora Account System (FAS2) account.
2. The SRPMs from the previous lab.

Preparation

Mock

• Install the mock package: yum install mock
• Add yourself to the mock group: usermod -G mock yourUserName

Koji

• Follow the procedure on the UsingKoji page on the Fedora wiki for setup instructions.

Steps

Testing BuildRequires with Mock

1. Run this command for each of your SRPMs: mock -r fedora-13-x86_64 yourSRPM
   • Replace fedora-13-x86_64 with the appropriate distribution-release-arch values. This must correspond to a config file in /etc/mock (without the .cfg extension).
   • Replace yourSRPM with the filename of the SRPM you wish to test.
2. If there are errors, they will be recorded in the results directory. Refer to the mock output for the location of the results directory, which will vary according to the mock configuration file used (if the configuration is fedora-13-x86_64, the results will be in /var/lib/mock/fedora-13-x86_64/result).
3. Correct any errors by adding appropriate BuildRequilres: tags, build the source RPM, and then retest.

Testing Builds on Other Architectures using Koji

Koji is a client-server system. Your computer runs the client software, which will submit the build job to a koji build hub. The build task will go through several states as it is picked up from the koji hub by a builder (a separate server system which retrieves jobs from the koji-hub and builds them) and that build either succeeds or fails.

Queueing the Build Request

To queue the build request on the main koji server, used for primary architecture builds (i386 and x86_64):

1. Issue the command: koji build dist-f14 --scratch yourSRPM
   • dist-f14 (called the Target) instructs koji to build the package using the packages available in the Fedora 14 distribution, and prepare it for inclusion in that distribution.
   • The --scratch option causes koji to build the package but not tag it for the target (i.e., not to include it in Fedora 14). To perform a build that will be passed to Bodhi for distribution, substitute --rebuild for --scratch and use a git URL for the package (do not do this until you have passed the package review and sponsor procedures!).
2. You can either follow the progress of the build by leaving the command running, or you may interrupt the koji command by pressing Ctrl-C once the message "this may be safely interrupted" is printed. Record the taskID printed for future reference.

To queue the build request on the koji server for another architecture, substitute arch-koji for the koji command. For example: arm-koji build dist-f18 --scratch foo*.src.rpm

Viewing the Build Request Status

You can view the status of a task through:

• The original koji command, if you did not interrupt it.
• The command: koji watch-task taskID
• Using the web interface.
  • For the primary arch koji system, go to https://koji.fedoraproject.org
  • For any of the secondary arch koji system, go to https://arch.koji.fedoraproject.org (e.g., http://arm.koji.fedoraproject.org for the ARM koji web interface)

Solving Architecture-Specific Errors Identified with Koji

Arch-Specific Conditionals

If your package does not build on a particular architecture using the same spec file contents as on the primary architectures, you can use architecture-specific conditionals to include or exclude parts of the spec file.

To include parts of a specfile only on a particular architecture (ppc in this example):

%ifarch ppc
BuildRequires: foo
%endif

To exclude parts of a specfile only on a particular architecture:

%ifnarch ppc
BuildRequires: bar
%endif

You can also use %else to specify alternation:

%ifarch ppc
%configure --baz
%else
%configure --qux
%endif

Excluding an Architecture

If a package will not build on a particular architecture, perhaps because the BuildRequires are not available on that arch, you can specify that the package should be excluded from that arch:

ExcludeArch: ppc

Arch Macros
Some architectures exist in multiple versions. In these cases, a macro is provided which expands to all of the arch names within a family; for example, to exclude all of the ARM varients, use ExcludeArch: %{arm}

Deliverable

Create a blog post describing your experience. Include:

• Notes on what you did, and what worked and didn't work.
• How long the process took.
• The results, including a link to your SRPM if it was modified from your previous lab.
• Your reflections on the tools, process, and experience.