How to deploy a charm to a specific machine in Amulet?

Question

How can I deploy two charms to the same node in Amulet testing?

Answer 1

If your use case requires more than 1 machine, i.e. you are testing a service that must be stood up on a different machine from its dependent services:

On the machine you manage your infrastructure with juju:

sudo pip install juju-deployerizer

Export your environment, including the location of all services/units:

juju deployerizer --environment <your environment> --include-placement -o <your export file.yaml>

Edit your export file, make sure to follow the format specified in the docs: http://pythonhosted.org/juju-deployer/config.html#placement

Some things to note: only 0 is recognized as a machine Id. If your testing environment calls for more than one machine: designate 1 service to be deployed without to: specification, then use that service name in the to: specification for all the other services/units needed on the new machine.

The default output of juju-deployerizer does not currently (05/2015) add the series information to the output, so just add it manually under the deployment name in your export file:

test:
    series: 'trusty'
    ...

Use the following to load your export file in the set up class method of your amulet test:

cls.deployment.load_bundle_file(bundle_file='<path to your export file.yaml>')

Proceed with the amulet tests as you normally would after that.