SCL (Software Collections Linux)

Table of Contents

1. Overview
2. Requirements
3. Role Variables
4. Dependencies
5. Examples
6. Development / Contributing
7. License
8. Author Information

Overview

This role installs and manages the SCL Software Collections repository, packages/collections for Fedora, CentOS, and Scientific Linux. Additionally it can create wrapper wrapper scripts to make calling the SCL collections binaries

Requirements

This role has been tested with Ansible 2.9 or higher and platform requirements are listed in the metadata file.

Compatibility

This role has been tested against the following distributions and Ansible version:

-	Distribution	Ansible 2.9
-	Centos 6	yes
-	Centos 7	yes

If you are looking for a version compatible with an older Ansible release please see the legacy branch

Role Variables

The variables that can be passed to this role and a brief description about them are as follows. (For all variables, take a look at defaults/main.yml)

# Toggle to enable creation/management
# of the SCL YUM repositories
scl_manage_repo: yes

# The Base URL location of the SCL sclo repository
scl_repo_sclo_sclo_baseurl:
  "http://mirror.centos.org/centos/{{ ansible_distribution_major_version }}/sclo/$basearch/sclo/"

# The Base URL location of the SCL rh repository
scl_repo_sclo_rh_baseurl:
  "http://mirror.centos.org/centos/{{ ansible_distribution_major_version }}/sclo/$basearch/rh"
  
# Array of wrapper scripts to create for SCL installed binaries
scl_wrappers:
  - {collection: 'rh-ruby23', command: 'ruby'}
  - {collection: 'rh-python35', command: 'python'}

# Array of Collections/Packages to install via SCL
scl_packages:
  - {name: 'rh-ruby23', state: 'latest'}
  - {name: 'rh-python35', state: 'latest'}

# Array (of hashes) of Ruby Gems to manage
scl_ruby_gems:
  - {
    ruby_ver: 'rh-ruby23',
    name: 'fast_github',
    state: 'present',
    }

# Array (of hashes) of Python PIPs to manage
scl_python_pips:
  - {
    python_ver: 'rh-python35',
    name: 'snakeoil',
    state: 'present',
    }

Dependencies

None

Example Playbook(s)

1. Management of the SCL YUM repositories

Disable repository management

roles:
  - role: ansible-role-scl
    scl_manage_repo: false

Modify YUM repository base URLs

roles:
  - role: ansible-role-scl
    scl_repo_sclo_sclo_baseurl:
      "http://mylocalmirror.local/centos/6/sclo/$basearch/sclo/"

1. Install wrapper scripts for SCL installed binaries

   The variable scl_wrappers generates wrapper/shebang scripts in /usr/local/bin:

   Each entry requires a hash with:

   • collection(required)
   • command(optional)

   If the command key is omited an scl wrapper script will be created

   scl-wrappper-[collection name] that can be used to call any command with with the collection sourced via SCL. For example listing all the PIPs installed under SCL rh-python35

   scl-wrapper-rh-python35 pip list

   If the command key is set an scl shebang script will be created that points to the command/binary specified.

   scl-shebang-[collection name] that can be used for inclusion in scripts. For example put the following in the wrapper line of a script written in ruby 2.2

   #!/usr/local/bin/scl-shebang-rh-ruby22

   The script will properly source all necessary environment variables for the desired ruby environment without having to declare scl enable rh-ruby22 -- ruby my_script.rb each time my_script.rb is run

   roles:
    - role: ansible-role-scl
      scl_wrappers:
        - {collection: 'rh-ruby22', command: 'ruby'}
        - {collection: 'rh-python35', command: 'python'}

2. Install SCL collections/packages via yum module

   Pre-compiled Gems/PIPs packages (RPMs) can be installed via the scl_packages variable.

   Each entry requires a hash with:

   • name(required)
   • state(optional)[defaults: present]

   roles:
    - role: ansible-role-scl
      scl_packages:
        - {name: 'rh-ruby22', state: 'latest'}
        - {name: 'rh-python35', state: 'latest'}

3. Manage SCL Python PIPs via pip module

   Each entry requires a hash with:

   • ruby_ver(required)
   • name(required)
   • state(optional)[defaults: present]
   • version(optional)[defaults: omit]

   roles:
    - role: ansible-role-scl
      scl_python_pips
        - {
          python_ver: 'rh-python35',
          name: 'snakeoil',
          state: 'present',
        }

4. Manage SCL Ruby GEMs via gem module

   Each entry requires a hash with:

   • python_ver(required)
   • name(required)
   • state(optional)[defaults: present]
   • version(optional)[defaults: omit]
   • source(optoinal)[defaults: omit]
   • pre_release(optional)[defaults: no]

   roles:
    - role: ansible-role-scl
      scl_ruby_gems
        - {
          ruby_ver: 'rh-ruby23',
          name: 'fast_github',
          state: 'present',
        }

5. AIO Example

   - role: ansible-role-scl
      scl_wrappers:
        - {collection: 'rh-ruby23', command: 'ruby'}
        - {collection: 'rh-python35', command: 'python'}
      scl_packages:
        - {name: 'rh-ruby23', state: 'latest'}
        - {name: 'rh-python35', state: 'latest'}
      scl_ruby_gems:
        - {
          ruby_ver: 'rh-ruby23',
          name: 'fast_github',
          state: 'present',
        }
      scl_python_pips:
        - {
          python_ver: 'rh-python35',
          name: 'snakeoil',
          state: 'present',
        }

6. Ansible include_role notation(s)

   Examples of including roles and tasks from the SCL Role using the new include_role module in Ansible 2.2+

   These examples give Ansible a more modular, class like feel which allows portions of a role to be included inside of additional playbooks with less duplication

   tasks:
     - name: "Add wrapper script for rh-ruby22"
       include_role:
         name: ansible-role-scl
         tasks_from: wrappers
       vars:
         scl_wrappers:
           - {collection: 'rh-ruby22', command: 'ruby'}
   
     - name: "Install rh-ruby22 from SCL"
       include_role:
         name: ansible-role-scl
         tasks_from: packages
       vars:
         scl_packages:
           - {name: 'rh-ruby22'}
   
     - name: "Install gems for rh-ruby22"
       include_role:
         name: ansible-role-scl
         tasks_from: gems
       vars:
         scl_ruby_gems:
           - {
             ruby_ver: 'rh-ruby22',
             name: 'fast_github',
             state: 'present',
           }

Development / Contributing

See Contributing.

Note: This role is currently only tested against the following OS and Ansible versions:

Operating Systems / version

• CentOS 6.x
• CentOS 7.x

Ansible Versions

• 2.9.0

License

Licensed under the MIT License. See the LICENSE file for details.

Author Information

• Steven Bambling