Exploring YAQL Expressions

The Newton release of Heat adds support for a yaql intrinsic function, which allows you to evaluate yaql expressions in your Heat templates. Unfortunately, the existing yaql documentation is somewhat limited, and does not offer examples of many of yaql’s more advanced features. I am working on a Fluentd composable service for TripleO. I want to allow each service to specify a logging source configuration fragment, for example: parameters: NovaAPILoggingSource: type: json description: Fluentd logging configuration for nova-api.
read more →

Heat-kubernetes Demo with Autoscaling

Next week is the Red Hat Summit in Boston, and I’ll be taking part in a Project Atomic presentation in which I will discuss various (well, two) options for deploying Atomic into an OpenStack environment, focusing on my heat-kubernetes templates. As part of that presentation, I’ve put together a short demonstration video: This shows off the autoscaling behavior available with recent versions of these templates (and also serves as a very brief introduction to working with Kubernetes).
read more →

Heat Hangout

I ran a Google Hangout this morning on Deploying with Heat. You can find the slides for the presentation on line here, and the Heat templates (as well as slide sources) are available on github. If you have any questions about the presentation, please feel free to ping me on irc (larsks).
read more →

Visualizing Heat stacks

I spent some time today learning about Heat autoscaling groups, which are incredibly nifty but a little opaque from the Heat command line, since commands such as heat resource-list don’t recurse into nested stacks. It is possible to introspect these resources (you can pass the physical resource id of a nested stack to heat resource-list, for example)… …but I really like visualizing things, so I wrote a quick hack called dotstack that will generate dot language output from a Heat stack.
read more →

Docker plugin bugs

This is a companion to my article on the Docker plugin for Heat. While writing that article, I encountered a number of bugs in the Docker plugin and elsewhere. I’ve submitted patches for most of the issues I encountered: Bugs in the Heat plugin https://bugs.launchpad.net/heat/+bug/1364017 docker plugin fails to delete a container resource in CREATE_FAILED state. https://bugs.launchpad.net/heat/+bug/1364041 docker plugin volumes_from parameter should be a list. https://bugs.launchpad.net/heat/+bug/1364039 docker plugin volumes_from parameter results in an error
read more →