Using Kolla For OpenStack Development

Kolla-ansible can be used to deploy containers in a way suitable for doing development on OpenStack services.

Heat was the first service to be supported, and so the following will use submitting a patch to Heat using Kolla as an example.

Warning

Kolla dev mode is intended for OpenStack hacking or development only. Do not use this in production!

Enabling Kolla “dev mode”

To enable dev mode for all supported services, set in /etc/kolla/globals.yml:

kolla_dev_mode: true

To enable it just for heat, set:

heat_dev_mode: true

Usage

When enabled, the source repo for the service in question will be cloned under /opt/stack/ on the target node(s). This will be bind mounted to container’s /dev-mode directory. From there, it will be installed at every startup of the container using kolla_install_projects script.

After making code changes, simply restart the container to pick them up:

docker restart heat_api

Debugging

remote_pdb can be used to perform debugging with Kolla containers. First, make sure it is installed in the container in question:

docker exec -it -u root heat_api pip install remote_pdb

Then, set your breakpoint as follows:

from remote_pdb import RemotePdb
RemotePdb('127.0.0.1', 4444).set_trace()

Once you run the code(restart the container), pdb can be accessed using socat:

socat readline tcp:127.0.0.1:4444

Learn more information about remote_pdb.