Ansible Role: pyenv

- hosts: localhost
  roles:
    - role: pyenv
      vars: { user: 'eric', install_release: '3.9.1' }

example playbook

Role Variables

No variables are required to run the role. The role will do a variety of things depending on which variables are defined (see examples below), but for those looking to just run it to install a particular version of python quickly for a particular user will need to have user + install_release defined OR user + default_release. The difference is basically whether you want that particular version of python to be merely accessible via pipenv, say for a particular project, or whether you want it to be the default python release for that user.

user

This is the user for which the subsequent pipenv configuration will occur. If this variable is not defined, pipenv will not be installed.

This variable must correspond to a single user on the system this role is being applied to, so if you want to configure pipenv for multiple users you must do something like this:

- hosts: localhost
  roles:
    - role: pyenv
      vars:
        user: "{{ item }}"
        release: '3.8.0'
      loop:
        - user1
        - user2
        - user3

default_release

This variable is used to set the default python interpreter for user. If the release specified has not been built by pipenv, then it will be built. This command is effectively a wrapper for pipenv global $RELEASE.

install_release

This variable is used to build a version of python from source as user via pipenv. For a list of possible options run: pipenv install --list. After runnning the role one with only the user variable defined. This command is effectively a wrapper for pipenv install $RELEASE.

Other Variables

The role makes use of other variables defined in defaults/main.yml which, under most circumstances you will not have any need to change. They mostly pertain to information regarding the user's shell. If you have a funky shell setup, see the section after Examples named "Additonal Variables" for more info.

Examples

- hosts: localhost
  roles:
    - role: pyenv

This will just install the system-wide packages required for a user to install pyenv and build their own python releases within their home directory without actually configuring pyenv for any particular user.

- hosts: localhost
  roles:
    - role: pyenv
      vars: { user: 'eric' }

This will both install the system packages needed to build python releases as well as install pyenv + pyenv-virtualenv for the user eric without actually building any python releases

- hosts: localhost
  roles:
    - role: pyenv
      vars: { user: 'eric', install_release: '3.9.1' }

This will do everything the two examples above do, however it will additionally build Python 3.9.1 as the user eric for use with pyenv.

- hosts: localhost
  roles:
    - role: pyenv
      vars: { user: 'eric', default_release: '3.9.1' }

Finally, the last example does all the things mentioned above, as well as set the default python bin for the user eric to ~/.pyenv/versions/3.9.1/bin/python.

The role is configured such that if you specify a default_release for a user that they have not yet built, it will automatically be built. Additionally, releases will not be re-built if they have already been installed.

Additional Variables

If your shell is configured to source it's default init file everytime a shell is opened you don't need to worry about these. In othe words, if your login shell is bash and you haven't changed it so that it won't source ~/.bashrc at some point when you open a new shell (or ~/.zshrc for zsh), then ignore everything below.

For the rest of you: the role will add the relevant pipenv init code to your login shells default rc file. This means there are two circumstances which you will want to change these additional variables:

1. the shell in which you work in is not the one defined in /etc/passwd as your login shell. This could be because you do something like exec tmux upon login or in your X init scripts or what have you. If you're not sure just see if the output of echo $SHELL matches the awk '/$USER/ {print $5} /etc/passwd/'; if it does not, keep reading.

2. The other quirky case is if you have configured your shell, for whatever reason, to ignore the default init script to be run upon launching a new shell, e.g. ~/.bashrc for bash or ~/.zshrc for zsh. The aformentioned files are where this role is going to addd the pipenv init commands, so keep reading if this is you.

user_shell

This is used to both:

• determine the path it should look for user_shell_rc
• to actually run pipenv commands once the init commands are placed in the correct shell rc file

If you need to adjust it any of the following values are acceptable:

• sh
• bash
• zsh
• csh

user_shell_rc

This is the name of the file that is considered the default rc script path for the shell defined in user_shell, the assumed values are

• ~/.bashrc for bash
• ~/.zshrc for zsh
• ~/.cshrc for csh
• POSTIX sh does not have a specified init rc file

License

MIT / BSD

Author Information

This role was created in 2021 by Spencer Smolen of Xtal Systems.