Ansible: installing pyenv on Centos

In one of our previous post we covered how to install Python 2.7 on Centos using pyenv which is a Python versions management tool. Today we will show how to use ansible to do that for you.  (If you are on Ubuntu you might want to check ansible-galaxy-pyenv .) Manual installation process is described here. This is how it looks like:

git clone git://github.com/yyuu/pyenv.git .pyenv
echo 'export PYENV_ROOT="$HOME/.pyenv"' >> ~/.bash_profile
echo 'export PATH="$PYENV_ROOT/bin:$PATH"' >> ~/.bash_profile
echo 'eval "$(pyenv init -)"' >> ~/.bash_profile
exec $SHELL
pyenv install 2.7.6
pyenv rehash

Pretty simple. But why bother to do it on each server command by command if you can use ansible?

It’s supposed you have some user (we use devops) which is able to log in to our target host (example.com) and is also able to run commands as root via sudo.

Here’s how to do that using a playbook:

- hosts:  example.com
  user: devops
  vars:
      home: home/devops

  tasks:
  - name: pyenv | check pyenv installed
    command: test -x {{ home }}/.pyenv/bin/pyenv
    register: pyenv_present
    ignore_errors: yes

  - name: pyenv | install devel packages
    sudo: yes
    yum:
        pkg: "{{ item }}"
        state: present
    with_items:
        - gcc
        - patch
        - sqlite-devel
        - readline-devel
        - openssl-devel

# http://hakunin.com/six-ansible-practices
  - name: ensure github.com is a known host
    lineinfile:
      dest: "{{ home }}/.ssh/known_hosts"
      create: yes
      state: present
      line: "{{ lookup('pipe', 'ssh-keyscan -t rsa github.com') }}"
      regexp: "^github\\.com"

  - name: pyenv | update pyenv repo
    git:  repo=git://github.com/yyuu/pyenv.git dest="{{ home }}/.pyenv/"
    when: pyenv_present|failed
    ignore_errors: yes

  - name: define environment variable 1 
    shell: echo 'export PYENV_ROOT="$HOME/.pyenv"' >> "{{ home }}/.bash_profile"
    when: pyenv_present|failed

  - name: define environment variable 2
    shell: echo 'export PATH="$PYENV_ROOT/bin:$PATH"' >> "{{ home }}/.bash_profile"
    when: pyenv_present|failed
   
  - name: add pyenv init to your shell to enable shims and autocompletion.
    shell: echo 'eval "$(pyenv init -)"' >> "{{ home }}/.bash_profile"
    when: pyenv_present|failed

  - name: install python versions into $PYENV_ROOT/versions
    sudo: no
    shell: " . {{ home }}/.bash_profile &&  pyenv install 2.7.6"
    when: pyenv_present|failed

  - name: rebuild the shim binaries
    sudo: no
    shell: " . {{ home }}/.bash_profile && pyenv rehash"
    when: pyenv_present|failed

  - name: list installed ruby version
    sudo: no
    shell: " . {{ home }}/.bash_profile && pyenv versions  "
    register: py_versions

  - debug: var=py_versions

Check:

ansible-playbook install_pyenv.yml -vvv -s --check

and run:

ansible-playbook install_pyenv.yml -vvv -s

After it’s done you can start using Python 2.7 on Centos:

[devops@example.com ~]$ python -V
Python 2.7.6
[devops@example.com ~]$