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distro package (Linux Distribution) version |version|

Official distro repository: distro official repo

Overview and motivation

.. automodule:: distro

If you want to jump into the API description right away, read about the consolidated accessor functions.

Compatibility

The distro package is supported on Python 3.7+ and PyPy, and on any Linux or BSD distribution that provides one or more of the data sources used by this package.

This package is tested on Python 3.7+ and PyPy, with test data that mimics the exact behavior of the data sources of a number of Linux distributions.

If you want to add test data for more distributions, please create an issue in the distro issue tracker and provide the following information in the issue:

  • The os-release file /etc/os-release if present, with a fall-back on /usr/lib/os-release if needed.
  • The file names and content of the /etc/*release and /etc/*version files, if any.
  • The output of the command: lsb_release -a, if available.
  • The file names and content of any other files you are aware of that provide useful information about the distro.

There are already some open issues on missing test data.

Data sources

The distro package implements a robust and inclusive way of retrieving the information about a Linux distribution based on new standards and old methods, namely from these data sources:

Access to the information

This package provides three ways to access the information about a Linux distribution:

  • Consolidated accessor functions

    These are module-global functions that take into account all data sources in a priority order, and that return information about the current Linux distribution.

    These functions should be the normal way to access the information.

    The precedence of data sources is applied for each information item separately. Therefore, it is possible that not all information items returned by these functions come from the same data source. For example, on a distribution that has an lsb_release command that returns the "Distributor ID" field but not the "Codename" field, and that has a distro release file that specifies a codename inside, the distro ID will come from the lsb_release command (because it has higher precedence), and the codename will come from the distro release file (because it is not provided by the lsb_release command).

    Examples: :func:`distro.id` for retrieving the distro ID, or :func:`distro.info` to get the machine-readable part of the information in a more aggregated way, or :func:`distro.linux_distribution` with an interface that is compatible to the original :py:func:`platform.linux_distribution` function, supporting a subset of its parameters.

  • Single source accessor functions

    These are module-global functions that take into account a single data source, and that return information about the current Linux distribution.

    They are useful for distributions that provide multiple inconsistent data sources, or for retrieving information items that are not provided by the consolidated accessor functions.

    Examples: :func:`distro.os_release_attr` for retrieving a single information item from the os-release data source, or :func:`distro.lsb_release_info` for retrieving all information items from the lsb_release command output data source.

  • LinuxDistribution class

    The :class:`distro.LinuxDistribution` class provides the main code of this package.

    This package contains a private module-global :class:`distro.LinuxDistribution` instance with default initialization arguments, that is used by the consolidated and single source accessor functions.

    A user-defined instance of the :class:`distro.LinuxDistribution` class allows specifying the path names of the os-release file and distro release file and whether the lsb_release command should be used or not. That is useful for example when the distribution information from a chrooted environment is to be retrieved, or when a distro has multiple distro release files and the default algorithm uses the wrong one.

Consolidated accessor functions

This section describes the consolidated accessor functions. See access to the information for a discussion of the different kinds of accessor functions.

.. autofunction:: distro.linux_distribution

.. autofunction:: distro.id

.. autofunction:: distro.name

.. autofunction:: distro.version

.. autofunction:: distro.version_parts

.. autofunction:: distro.major_version

.. autofunction:: distro.minor_version

.. autofunction:: distro.build_number

.. autofunction:: distro.like

.. autofunction:: distro.codename

.. autofunction:: distro.info

Single source accessor functions

This section describes the single source accessor functions. See access to the information for a discussion of the different kinds of accessor functions.

.. autofunction:: distro.os_release_info

.. autofunction:: distro.lsb_release_info

.. autofunction:: distro.distro_release_info

.. autofunction:: distro.uname_info

.. autofunction:: distro.os_release_attr

.. autofunction:: distro.lsb_release_attr

.. autofunction:: distro.distro_release_attr

.. autofunction:: distro.uname_attr

LinuxDistribution class

This section describes the access via the :class:`distro.LinuxDistribution` class. See access to the information for a discussion of the different kinds of accessor functions.

.. autoclass:: distro.LinuxDistribution
   :members:
   :undoc-members:

Normalization tables

These translation tables are used to normalize the parsed distro ID values into reliable IDs. See :func:`distro.id` for details.

They are documented in order to show for which distros a normalization is currently defined.

As a quick fix, these tables can also be extended by the user by appending new entries, should the need arise. If you have a need to get these tables extended, please make an according request in the distro issue tracker.

.. autodata:: distro.NORMALIZED_OS_ID

.. autodata:: distro.NORMALIZED_LSB_ID

.. autodata:: distro.NORMALIZED_DISTRO_ID

Os-release file

The os-release file is looked up using the path name /etc/os-release. Its optional additional location /usr/lib/os-release would be looked up for if the former couldn't be read.

The os-release file is expected to be encoded in UTF-8.

It is parsed using the standard Python :py:mod:`shlex` package, which treats it like a shell script.

The attribute names found in the file are translated to lower case and then become the keys of the information items from the os-release file data source. These keys can be used to retrieve single items with the :func:`distro.os_release_attr` function, and they are also used as keys in the dictionary returned by :func:`distro.os_release_info`.

The attribute values found in the file are processed using shell rules (e.g. for whitespace, escaping, and quoting) before they become the values of the information items from the os-release file data source.

If the attribute "VERSION" is found in the file, the distro codename is extracted from its value if it can be found there. If a codename is found, it becomes an additional information item with key "codename".

See the os-release man page for a list of possible attributes in the file.

Examples:

  1. The following os-release file content:

    NAME='Ubuntu'
VERSION="14.04.3 LTS, Trusty Tahr"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 14.04.3 LTS"
VERSION_ID="14.04"
HOME_URL="http://www.ubuntu.com/"
SUPPORT_URL="http://help.ubuntu.com/"
BUG_REPORT_URL="http://bugs.launchpad.net/ubuntu/"

    results in these information items:

    Key

    Value

    name

    "Ubuntu"

    version

    "14.04.3 LTS, Trusty Tahr"

    id

    "ubuntu"

    id_like

    "debian"

    pretty_name

    "Ubuntu 14.04.3 LTS"

    version_id

    "14.04"

    home_url

    "http://www.ubuntu.com/"

    support_url

    "http://help.ubuntu.com/"

    bug_report_url

    "http://bugs.launchpad.net/ubuntu/"

    codename

    "Trusty Tahr"

  2. The following os-release file content:

    NAME="Red Hat Enterprise Linux Server"
VERSION="7.0 (Maipo)"
ID="rhel"
ID_LIKE="fedora"
VERSION_ID="7.0"
PRETTY_NAME="Red Hat Enterprise Linux Server 7.0 (Maipo)"
ANSI_COLOR="0;31"
CPE_NAME="cpe:/o:redhat:enterprise_linux:7.0:GA:server"
HOME_URL="https://www.redhat.com/"
BUG_REPORT_URL="https://bugzilla.redhat.com/"

REDHAT_BUGZILLA_PRODUCT="Red Hat Enterprise Linux 7"
REDHAT_BUGZILLA_PRODUCT_VERSION=7.0
REDHAT_SUPPORT_PRODUCT="Red Hat Enterprise Linux"
REDHAT_SUPPORT_PRODUCT_VERSION=7.0

    results in these information items:

    Key

    Value

    name

    "Red Hat Enterprise Linux Server"

    version

    "7.0 (Maipo)"

    id

    "rhel"

    id_like

    "fedora"

    version_id

    "7.0"

    pretty_name

    "Red Hat Enterprise Linux Server 7.0 (Maipo)"

    ansi_color

    "0;31"

    cpe_name

    "cpe:/o:redhat:enterprise_linux:7.0:GA:server"

    home_url

    "https://www.redhat.com/"

    bug_report_url

    "https://bugzilla.redhat.com/"

    redhat_bugzilla_product

    "Red Hat Enterprise Linux 7"

    redhat_bugzilla_product_version

    "7.0"

    redhat_support_product

    "Red Hat Enterprise Linux"

    redhat_support_product_version

    "7.0"

    codename

    "Maipo"

Lsb_release command output

The lsb_release command is expected to be in the PATH, and is invoked as follows:

lsb_release -a

The command output is expected to be encoded in UTF-8.

Only lines in the command output with the following format will be used:

<attr-name>: <attr-value>

Where:

  • <attr-name> is the name of the attribute, and
  • <attr-value> is the attribute value.

The attribute names are stripped from surrounding blanks, any remaining blanks are translated to underscores, they are translated to lower case, and then become the keys of the information items from the lsb_release command output data source.

The attribute values are stripped from surrounding blanks, and then become the values of the information items from the lsb_release command output data source.

See the lsb_release man page for a description of standard attributes returned by the lsb_release command.

Examples:

  1. The following lsb_release command output:

    No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 14.04.3 LTS
Release:        14.04
Codename:       trusty

    results in these information items:

    Key

    Value

    distributor_id

    "Ubuntu"

    description

    "Ubuntu 14.04.3 LTS"

    release

    "14.04"

    codename

    "trusty"

  2. The following lsb_release command output:

    LSB Version:    n/a
Distributor ID: SUSE LINUX
Description:    SUSE Linux Enterprise Server 12 SP1
Release:        12.1
Codename:       n/a

    results in these information items:

    Key

    Value

    lsb_version

    "n/a"

    distributor_id

    "SUSE LINUX"

    description

    "SUSE Linux Enterprise Server 12 SP1"

    release

    "12.1"

    codename

    "n/a"

Distro release file

Unless specified with a particular path name when using the :class:`distro.LinuxDistribution` class, the distro release file is found by using the first match in the alphabetically sorted list of the files matching the following path name patterns:

  • /etc/*-release
  • /etc/*_release
  • /etc/*-version
  • /etc/*_version

where the following special path names are excluded:

  • /etc/debian_version
  • /etc/system-release
  • /etc/os-release

and where the first line within the file has the expected format.

The algorithm to sort the files alphabetically is far from perfect, but the distro release file has the least priority as a data source, and it is expected that distributions provide one of the other data sources.

The distro release file is expected to be encoded in UTF-8.

Only its first line is used, and it is expected to have the following format:

<name> [[[release] <version_id>] (<codename>)]

Where:

  • square brackets indicate optionality,
  • <name> is the distro name,
  • <version_id> is the distro version, and
  • <codename> is the distro codename.

The following information items can be found in a distro release file (shown with their keys and data types):

  • id (string): Distro ID, taken from the first part of the file name before the hyphen (-) or underscore (_).

    Note that the distro ID is not normalized or translated to lower case at this point; this happens only for the result of the :func:`distro.id` function.

  • name (string): Distro name, as found in the first line of the file.

  • version_id (string): Distro version, as found in the first line of the file. If not found, this information item will not exist.

  • codename (string): Distro codename, as found in the first line of the file. If not found, this information item will not exist.

    Note that the string in the codename field is not always really a codename. For example, openSUSE returns "x86_64".

Examples:

  1. The following distro release file /etc/centos-release:

    CentOS Linux release 7.1.1503 (Core)

    results in these information items:

    Key

    Value

    id

    "centos"

    name

    "CentOS Linux"

    version_id

    "7.1.1503"

    codename

    "Core"

  2. The following distro release file /etc/oracle-release:

    Oracle Linux Server release 7.1

    results in these information items:

    Key

    Value

    id

    "oracle"

    name

    "Oracle Linux Server"

    version_id

    "7.1"

  3. The following distro release file /etc/SuSE-release:

    openSUSE 42.1 (x86_64)

    results in these information items:

    Key

    Value

    id

    "SuSE"

    name

    "openSUSE"

    version_id

    "42.1"

    codename

    "x86_64"