pyenv

Pyenv provides a way to build and use Pythons outside of your platforms package manager's purview.

Table of contents

1. Overview - What is the pyenv module?
2. Module description - What is the purpose of this mdoule?
3. Setup - The basics of getting started with pyenv
   • Beginning with pyenv - Installation
   • Installing a Python - Basic options for getting started
   • Relocating pyenv
4. Usage - The classes and types available for configuration
   • Classes
     • Class: pyenv
   • Types
     • Type: pyenv_python

Overview

The pyenv module allows you to install pyenv on a target system. The module also provides a Puppet type called pyenv_python which will instruct pyenv to build a Python for you.

This module only supports global installations of pyenv, meaning it will not install into a user's home directory. Though it can be made to do so the types that come with it do not support this work flow.

Module description

Python is a often-used programming language ranging from simple scripts to automate a repetitive task to powering large (web) applications. The problem we often encounter is that a distribution only ships with one (outdated) Python version. Pyenv remedies this situation by allow you to build your own Pythons and use those instead.

Setup

This modules will:

• Install pyenv for you. It will do so by checking out the latest tag at the time this module was written;
• Symlink pyenv so that it will be found when looking through $PATH;
• Install the necessary packages to ensure you can build Python;
• A type and provider to make Puppet build Pythons through pyenv.

This module requires:

• puppetlabs/stdlib
• puppetlabs/vcsrepo

Beginning with pyenv

In order to install pyenv with the defaults:

include ::pyenv

This will install pyenv for you in /usr/local/pyenv and symlink /usr/local/bin/pyenv to /usr/local/pyenv/bin/pyenv.

Installing a Python

Use the pyenv_python type to instruct Puppet to build a Python:

pyenv_python { '3.4.0': }

The pyenv_python defaults to ensure => present,, therefor you do not need to specify it yourself.

If you want to build a debug version of a Python add -debug to the name of the Python:

pyenv_python { '3.4.0-debug': }

Relocation the pyenv installation

The module installs pyenv to /usr/local/pyenv by default and symlinks the pyenv binary onto your path. This is needed so that the provider can find pyenv and set up the PYENV_ROOT environment variable accordingly.

If you change the location of the pyenv checkout you must either:

• Make sure the symlink is changed too. This is done automatically if you set symlink_pyenv to true;
• Create a custom Fact called pyenv_binary with the location of /path/to/checkout/bin/pyenv.

The former of the two methods is preferred if at all possible.

If Puppet's $PATH does not by default include /usr/local/bin either add that to it or change the symlink_path to a different location that is part of Puppet's $PATH.

Usage

Classes and defined types

Class: pyenv

The pyenv module's primary and only class, pyenv sets up your system with pyenv and the necessary packages to compile.

It takes the following parameters:

• ensure_repo: Whether to add or remove the repository
  • default: present
  • options: present, absent
• repo_location: Where to checkout the repository on the filesystem
  • default: /usr/local/pyenv
  • options: any absolute path
• repo_revision: The revision to checkout
  • default: v0.4.0-20140404
  • options: tag, commit SHA, branch
• symlink_pyenv: Create a symlink to the pyenv binary
  • default: true
  • options: true, false
• symlink_path: Where to symlink pyenv to
  • default: /usr/local/bin
  • options: any absolute path known to $PATH
• manage_packages: Install packages needed to compile Python
  • default: true
  • options: true, false
• ensure_packages: State of the packages to ensure
  • default: latest
  • options: any valid value for the ensure attribute of the package type
• python_build_packages: Array/list of packages to install
  • default: depends on what Facter returns for osfamily, see (params.pp)[params.pp]
  • options: an array of strings representing package names

Types

Type: pyenv_python

pyenv_python allows you to build a Python which in turn will make it available to someone wishing to use it.

It takes the following options:

• name (namevar): name of the Python to be installed, see pyenv install -l. If omitted the title of the resource will be used.
• ensure: state the Python should be in
  • default: present
  • options: valid values for ensure
• keep: keep the sources after compiling
  • default: false
  • options: true, false
• virtualenv: Install virtualenv in the new Python
  • default: false
  • options: true, false

Keep one thing in mind: if a Python was installed without setting keep to true you cannot add it later, the provider will call the fail() method in such cases.