pbr/doc/source/user/using.rst

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Usage

pbr is a setuptools plugin and so to use it you must use setuptools and call setuptools.setup(). While the normal setuptools facilities are available, pbr makes it possible to express them through static data files.

setup.py

pbr only requires a minimal setup.py file compared to a standard setuptools project. This is because most configuration is located in static configuration files. This recommended minimal setup.py file should look something like this:

#!/usr/bin/env python

from setuptools import setup

setup(
    setup_requires=['pbr'],
    pbr=True,
)

Note

It is necessary to specify pbr=True to enabled pbr functionality.

Note

While one can pass any arguments supported by setuptools to setup(), any conflicting arguments supplied in setup.cfg will take precedence.

setup.cfg

The setup.cfg file is an ini-like file that can mostly replace the setup.py file. It is based on the distutils2 setup.cfg file. A simple sample can be found in pbr's own setup.cfg (it uses its own machinery to install itself):

[metadata]
name = pbr
author = OpenStack Foundation
author-email = openstack-dev@lists.openstack.org
summary = OpenStack's setup automation in a reusable form
description-file = README.rst
description-content-type = text/x-rst; charset=UTF-8
home-page = https://launchpad.net/pbr
license = Apache-2
classifier =
    Development Status :: 4 - Beta
    Environment :: Console
    Environment :: OpenStack
    Intended Audience :: Developers
    Intended Audience :: Information Technology
    License :: OSI Approved :: Apache Software License
    Operating System :: OS Independent
    Programming Language :: Python
keywords =
    setup
    distutils

[files]
packages =
    pbr
data_files =
    etc/pbr = etc/*
    etc/init =
        pbr.packaging.conf
        pbr.version.conf

[entry_points]
console_scripts =
    pbr = pbr.cmd:main
pbr.config.drivers =
    plain = pbr.cfg.driver:Plain

pbr provides its own section in these documents, ostensibly called pbr, and provides a custom version of Sphinx's build_sphinx section. Most other sections are provided by setuptools and may influence either the build itself or the output of various setuptools commands. The remaining sections are provided by libraries that provide setuptools extensions, such as extract_mesages (provided by Babel). Some of these are described below.

Note

Comments may be used in setup.cfg, however all comments should start with a # and may be on a single line, or in line, with at least one white space character immediately preceding the #. Semicolons are not a supported comment delimiter. For instance:

[section]
# A comment at the start of a dedicated line
key =
    value1 # An in line comment
    value2
    # A comment on a dedicated line
    value3

files

The files section defines the install location of files in the package using three fundamental keys: packages, namespace_packages, and data_files.

packages

A list of top-level packages that should be installed. The behavior of packages is similar to setuptools.find_packages in that it recurses the python package hierarchy below the given top level and installs all of it. If packages is not specified, it defaults to the value of the name field given in the [metadata] section.

namespace_packages

Similar to packages, but is a list of packages that provide namespace packages.

data_files

A list of files to be installed. The format is an indented block that contains key value pairs which specify target directory and source file to install there. More than one source file for a directory may be indicated with a further indented list. Source files are stripped of leading directories. Additionally, pbr supports a simple file globbing syntax for installing entire directory structures, thus:

[files]
data_files =
    etc/pbr = etc/pbr/*
    etc/neutron =
        etc/api-paste.ini
        etc/dhcp-agent.ini
    etc/init.d = neutron.init

will result in /etc/neutron containing api-paste.ini and dhcp-agent.ini, both of which pbr will expect to find in the etc directory in the root of the source tree. Additionally, neutron.init from that dir will be installed in /etc/init.d. All of the files and directories located under etc/pbr in the source tree will be installed into /etc/pbr.

Note that this behavior is relative to the effective root of the environment into which the packages are installed, so depending on available permissions this could be the actual system-wide /etc directory or just a top-level etc subdirectory of a virtualenv.

pbr

The pbr section controls pbr specific options and behaviours.

autodoc_tree_index_modules

A boolean option controlling whether pbr should generate an index of modules using sphinx-apidoc. By default, all files except setup.py are included, but this can be overridden using the autodoc_tree_excludes option.

autodoc_tree_excludes

A list of modules to exclude when building documentation using sphinx-apidoc. Defaults to [setup.py]. Refer to the sphinx-apidoc man page for more information.

autodoc_index_modules

A boolean option controlling whether pbr should itself generates documentation for Python modules of the project. By default, all found Python modules are included; some of them can be excluded by listing them in autodoc_exclude_modules.

autodoc_exclude_modules

A list of modules to exclude when building module documentation using pbr. fnmatch style pattern (e.g. myapp.tests.*) can be used.

api_doc_dir

A subdirectory inside the build_sphinx.source_dir where auto-generated API documentation should be written, if autodoc_index_modules is set to True. Defaults to "api".

Note

When using autodoc_tree_excludes or autodoc_index_modules you may also need to set exclude_patterns in your Sphinx configuration file (generally found at doc/source/conf.py in most OpenStack projects) otherwise Sphinx may complain about documents that are not in a toctree. This is especially true if the [sphinx_build] warning-is-error option is set. See the Sphinx build configuration file documentation for more information on configuring Sphinx.

2.0

The pbr section used to take a warnerrors option that would enable the -W (Turn warnings into errors.) option when building Sphinx. This feature was broken in 1.10 and was removed in pbr 2.0 in favour of the [build_sphinx] warning-is-error provided in Sphinx 1.5+.

build_sphinx

The build_sphinx section is a version of the build_sphinx setuptools plugin provided with Sphinx. This plugin extends the original plugin to add the following:

  • Automatic generation of module documentation using the apidoc tool

  • Automatic configuration of the project, version and release settings using information from pbr itself

  • Support for multiple builders using the builders configuration option

    Note

    Only applies to Sphinx < 1.6. See documentation on builders below.

The version of build_sphinx provided by pbr provides a single additional option.

builders

A comma separated list of builders to run. For example, to build both HTML and man page documentation, you would define the following in your `setup.cfg`:

[build_sphinx]
builders = html,man
source-dir = doc/source
build-dir = doc/build
all-files = 1
warning-is-error = 1

3.2.0

Sphinx 1.6+ adds support for specifying multiple builders in the default builder option. You should use this option instead. Refer to the Sphinx documentation for more information.

For information on the remaining options, refer to the Sphinx documentation. In addition, the autodoc_index_modules, autodoc_tree_index_modules, autodoc_exclude_modules and autodoc_tree_excludes options in the pbr section will affect the output of the automatic module documentation generation.

3.0

The build_sphinx plugin used to default to building both HTML and man page output. This is no longer the case, and you should explicitly set builders to html man if you wish to retain this behavior.

entry_points

The entry_points section defines entry points for generated console scripts and python libraries. This is actually provided by setuptools but is documented here owing to its importance.

The general syntax of specifying entry points is a top level name indicating the entry point group name, followed by one or more key value pairs naming the entry point to be installed. For instance:

[entry_points]
console_scripts =
    pbr = pbr.cmd:main
pbr.config.drivers =
    plain = pbr.cfg.driver:Plain
    fancy = pbr.cfg.driver:Fancy

Will cause a console script called pbr to be installed that executes the main function found in pbr.cmd. Additionally, two entry points will be installed for pbr.config.drivers, one called plain which maps to the Plain class in pbr.cfg.driver and one called fancy which maps to the Fancy class in pbr.cfg.driver.

Requirements

Requirement files should be given one of the below names. This order is also the order that the requirements are tried in (where N is the Python major version number used to install the package):

  • requirements-pyN.txt
  • tools/pip-requires-py3
  • requirements.txt
  • tools/pip-requires

Only the first file found is used to install the list of packages it contains.

Note

The 'requirements-pyN.txt' file is deprecated - 'requirements.txt' should be universal. You can use Environment markers for this purpose.

Extra requirements

Groups of optional dependencies, or "extra" requirements, can be described in your setup.cfg, rather than needing to be added to setup.py. An example (which also demonstrates the use of environment markers) is shown below.

Environment markers

Environment markers are conditional dependencies which can be added to the requirements (or to a group of extra requirements) automatically, depending on the environment the installer is running in. They can be added to requirements in the requirements file, or to extras defined in setup.cfg, but the format is slightly different for each.

For requirements.txt:

argparse; python_version=='2.6'

This will result in the package depending on argparse only if it's being installed into Python 2.6

For extras specified in setup.cfg, add an extras section. For instance, to create two groups of extra requirements with additional constraints on the environment, you can use:

[extras]
security =
    aleph
    bet:python_version=='3.2'
    gimel:python_version=='2.7'
testing =
    quux:python_version=='2.7'

Testing

pbr overrides the setuptools hook test (i.e. setup.py test). The following sequence is followed:

  1. If a .testr.conf file exists and testrepository is installed, pbr will use it as the test runner. See the testr documentation for more details.

    Note

    This is separate to setup.py testr (note the extra r) which is provided directly by the testrepository package. Be careful as there is some overlap of command arguments.

  2. Although deprecated, if [nosetests] is defined in setup.cfg and nose is installed, the nose runner will be used.

  3. In other cases no override will be installed and the test command will revert to setuptools.

A typical usage would be in tox.ini such as:

[tox]
minversion = 2.0
skipsdist = True
envlist = py33,py34,py35,py26,py27,pypy,pep8,docs

[testenv]
usedevelop = True
setenv =
  VIRTUAL_ENV={envdir}
  CLIENT_NAME=pbr
deps = .
     -r{toxinidir}/test-requirements.txt
commands =
  python setup.py test --testr-args='{posargs}'

The argument --coverage will set PYTHON to coverage run to produce a coverage report. --coverage-package-name can be used to modify or narrow the packages traced.