Trove/MoveTroveGuest

Description

Currently the Trove Guest Agent code is contained in the trove module. This blueprint goal is to split the guest agent specific code into another top level module called 'troveguest'. This will eventually be split out completely into another repository, the first step is to refactor the code so it is no longer dependent on trove core.

Justification/Benefits

• Simplify installation of the guest agent on instances.
• Reduce the amount of code that is deployed on instances.
• Lower the memory footprint of the guest agent by not importing unnecessary code from Trove core.

Impacts

• The setup.cfg will need to setup the new module along with trove. See horizon for an example.
• An example setup.cfg for just packaging the guest agent will be added along with a build_guest.py helper script.
• Some in flight reviews will have a difficult rebase. (Cores will also need to be careful to merge them in order to minimize impact)

Configuration

• A new top level olso.cfg for the troveguest will be added. (This should be a small subset of the values in trove.common.cfg)
• The values in trove.common.cfg that are specifically for the guest will be removed.
• It is possible that some configuration values will need to be added or duplicated.

Database

None

Public API

None

Internal API

None

Guest Agent

1. The guest agent code will be moved to a top level module in the existing trove repository called 'troveguest'.
2. The import statements will be changed from 'trove.guestagent' to 'troveguest'
3. Some common code will need to be duplicated within the troveguest so that there are no dependancies on the trove core. (This should hopefully be minimal)
4. The code that currently rsync's the code over to instances in development will be changed to just include the 'troveguest' module. (It is possible that another delivery method will be used, however that should probably be done in its own blueprint)

setup.cfg

Add a new package to the [files] section

[files]
packages =
    trove
    troveguest

new troveguest module =

Move the trove.guest module to troveguest so the layout looks like:

trove/
        ...
        doc/
        etc/
        tools/
        trove/
        troveguest/   < --- new module
        setup.py
        setup.cfg 
        ...  

add new openstack-common.conf

Add file `troveguest/openstack-common.conf ` and add only the modules that the guest needs (this needs to be discoverd)

1. Clone the osloincubator repo: `git clone git@github.com:openstack/oslo-incubator.git`
2. Run the update script: `python update.py --config-file ../trove/troveguest/openstack-common.conf`

Example config:

[DEFAULT]

# The list of modules to copy from oslo-incubator
module=eventlet_backdoor
module=exception
module=excutils
module=fileutils
module=gettextutils
module=importutils
module=jsonutils
module=local
module=lockutils
module=log
module=loopingcall
module=pastedeploy
module=periodic_task
module=processutils
module=rpc
module=service
module=strutils
module=testutils
module=threadgroup
module=timeutils
module=utils
module=versionutils

# The base module to hold the copy of openstack.common
base=troveguest

Move tests and add a test runner for the guest

The guestagent tests need to be split out from the trove.tests modules then we to make sure the tests are discovered properly.

Possibly modify tox.ini:

[testenv:cover]
basepython = python2.7
commands =
     {envpython} run_tests.py --group=does_not_exist
     coverage erase
     python setup.py testr --coverage
     coverage run -a run_tests.py
     coverage run -a troveguest/run_tests.py
     coverage html
     coverage report