An introduction to OpenStack Heat

Fri 06 December 2013 by Lars Kellogg-Stedman Tags openstack heat neutron

Heat is a template-based orchestration mechanism for use with OpenStack. With Heat, you can deploy collections of resources -- networks, servers, storage, and more -- all from a single, parameterized template.

In this article I will introduce Heat templates and the heat command line client.

Writing templates

Because Heat began life as …

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A Python interface to signalfd() using FFI

Thu 28 November 2013 by Lars Kellogg-Stedman Tags python

I just recently learned about the signalfd(2) system call, which was introduced to the Linux kernel back in 2007:

signalfd() creates a file descriptor that can be used to accept signals targeted at the caller. This provides an alternative to the use of a signal handler or sigwaitinfo(2 …

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Long polling with Javascript and Python

In this post I'm going to step through an example web chat system implemented in Python (with Bottle and gevent) that uses long polling to implement a simple publish/subscribe mechanism for efficiently updating connected clients.

My pubsub_example repository on GitHub has a complete project that implements the ideas discussed …

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Sockets on OpenShift

Sat 23 November 2013 by Lars Kellogg-Stedman Tags openshift javascript

In this article, a followup to my previous post regarding long-poll servers and Python, we investigate the code changes that were necessary to make the code work when deployed on OpenShift.

In the previous post, we implemented IO polling to watch for client disconnects at the same time we were …

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A unified CLI for OpenStack

Fri 22 November 2013 by Lars Kellogg-Stedman Tags openstack

The python-openstackclient project, by Dean Troyer and others, is a new command line tool to replace the existing command line clients (including commands such as nova, keystone, cinder, etc).

This tool solves two problems I've encountered in the past:

  • Command line options between different command line clients are sometimes inconsistent …

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