bu-ist / bux-grader-configuration

A set of Ansible playbooks for quick provisioning of external graders.

BUx Grader Configuration

Bootstrapping of BUx external grader environments for use with the BUx Grader Framework.

Provisioning is accomplished using Ansible.

In addition a Vagrantfile is provided for quick setup of local development VMs with Vagrant.

Prerequisites

In order for the grader to start it must be able to succesfully connect to a running XQueue instance. If your course will be hosted on edx.org, contact your program manager to set up your course queue and obtain credentials. See the course author docs on external graders for more details.

For development purposes you might consider standing up your own edX platform using the edX configuration repository. See the Wiki page for installation options.

Getting Started

Clone this repository to your build machine and install the requirements. Use of virtualenv is highly recommended.

$ git clone [e-mail]:bu-ist/bux-grader-configuration
$ cd bux-grader-configuration
$ pip install -r requirements.txt

Configuration

The playbook uses roles which depend on the existence of a few variables.

grader_repos: https://github.com/your-grader-repository
grader_version: develop
grader_settings_module: settings

The grader role will look for a top-level requirements.txt file in your course repository, which it will use to populate a virtualenv if found.

The grader_settings_module variable should refer to a settings module that is importable by Python from your repository root.

For example, if your settings module is located in settings/production.py, the grader_settings_module should be set to settings.production.

Setting up a development VM

Prerequisites

1. VirtualBox (https://www.virtualbox.org/)
2. Vagrant (http://www.vagrantup.com)
3. vagrant-vbguest plugin (https://github.com/dotless-de/vagrant-vbguest) (Optional)
4. vagrant-hostupdater plugin (https://github.com/cogitatio/vagrant-hostsupdater) (Optional)

Setup

1. Add your grader-specific configuration vars to playbooks/group_vars/vagrant
2. Run vagrant up to install and boot the VM and start provisioning with Ansible

The first run will take a while -- consider grabbing a coffee or calling your grandmother.

Once it's completed, the grader should be up and polling xqueue inside the VM.

Shared Folders

The VM will mount two shared folders for your development convenience:

• grader - /edx/app/grader/grader
• venv - /edx/app/grader/venv

Provisioning a Remote Server with Ansible

1. Add an inventory file to playbooks/inventory describing the remote system to be provisioned
2. Add your grader-specific configuration (see playbooks/group_vars/all for examples)
3. Provision with ansible-playbook -i inventory/file grader.yml

Managing the Grader

# Check grader status
$ /edx/bin/supervisorctl status

# Start / stop grader
$ /edx/bin/supervisorctl start|stop bux-grader