Packaging Python

Stephen Thorne

NetBox Blue Pty Ltd

Introduction

• NetBox Blue uses a lot of python.
• We package our software using rpm.
• We maintain 32 packages containing upstream codebases.

Packaging Rationale

• Installing
• Upgrading
• Verification
• Removing
• cp foo-1.1/foo /usr/lib/python2.5/site-packages/ doesn't cut it

Tools

• rpmbuild
• distutils
• pkg_resources
• setuptools/eggs

rpmbuild

• Quick Introduction
• Require a .spec file and sources in .tar.gz form.
• Sources go in SOURCES directory.
• rpmbuild -ba /path/to/spec

Specfile Example

%define name examplepackage
%define version 0.1
%define release 1

Summary: An example package
Name: %{name}
Version: %{version}
Release: %{release}
Source0: %{name}-%{version}.tar.gz
License: UNKNOWN
Group: Development/Libraries
BuildRoot: %{_tmppath}/%{name}-%{version}-%{release}-buildroot
Prefix: %{_prefix}
BuildArch: noarch
Vendor: Bob Smith <bob@smith.com>
Url: http://example.com/foo/

%description
UNKNOWN

%prep
%setup

%build
python setup.py build

%install
python setup.py install --root=$RPM_BUILD_ROOT --record=INSTALLED_FILES

%clean
rm -rf $RPM_BUILD_ROOT

%files -f INSTALLED_FILES
%defattr(-,root,root)

Distutils

• Platform agnostic definition of python packages.
• Create setup.py
• Fill it like this:

from distutils.core import setup

setup(
    name = 'examplepackage',
    version = "0.1",
    description = "Example package",
    author = "Bob Smith",
    author_email = "bob@smith.com",
    url = "http://example.com/foo",
    packages = ['examplepackage'],
    scripts = ['bin/examplescript'],
    )

Package layout

• foo-1.0/setup.py
• foo-1.0/examplepackage
• foo-1.0/bin

Using bdist_*

• bdist_rpm will automatically create a spec file and build the rpm.
• python setup.py bdist_rpm
• rpm -i dist/examplepackage-0.1-1.noarch.rpm

Setuptools

• Creates python eggs.
• Extends the functionality provided by distutils.
• Answer to ruby 'gems'.
• Can still create packages in the normal way.
• Will create directories that look like SQLObject-0.10.1-py2.4.egg-info

pythonpackage

• A script I wrote.
• Demo of building packages on different systems.

Editing a spec file

• python setup.py bdist_rpm --spec-only
• python setup.py bdist_rpm --source-only
• rpm -i dist/examplepackage-0.1-1.src.rpm
• rpmbuild -ba dist/examplepackage.spec