Table of Contents

Implementation

The engine (tractor-engine) is a high performance, multi-threaded C++ application. It responds to HTTP transaction requests, and maintains a database of spooled jobs.

The Blades are a straightforward execution server, written in Python, and providing site-extensible modules and role configuration.

The Dashboard provides job tracking, visualization, and control widgets developed on a modern HTML5/CSS3/JavaScript framework. Each user's Dashboard layout and preferences are maintained in a per-user section of the engine's data area.

New jobs are typically spooled into the queue as Alfred-format job scripts that are automatically processed by the engine and stored as job, task, and command records in a database (currently PostgreSQL). Jobs are usually spooled to the engine by running the supplied tractor-spool command-line script. There is also a supplied Python job authoring module that provides a scriptable API for creating jobs and submitting them.