openstacksdk/doc/source/user/config/using.rst

Using openstack.config in an Application

Usage

The simplest and least useful thing you can do is:

python -m openstack.config.loader

Which will print out whatever if finds for your config. If you want to use it from python, which is much more likely what you want to do, things like:

Get a named cloud.

import openstack.config

cloud_config = openstack.config.OpenStackConfig().get_one_cloud(
    'internap', region_name='ams01')
print(cloud_config.name, cloud_config.region, cloud_config.config)

Or, get all of the clouds.

import openstack.config

cloud_config = openstack.config.OpenStackConfig().get_all_clouds()
for cloud in cloud_config:
    print(cloud.name, cloud.region, cloud.config)

argparse

If you're using openstack.config from a program that wants to process command line options, there is a registration function to register the arguments that both openstack.config and keystoneauth know how to deal with - as well as a consumption argument.

import argparse
import sys

import openstack.config

cloud_config = openstack.config.OpenStackConfig()
parser = argparse.ArgumentParser()
cloud_config.register_argparse_arguments(parser, sys.argv)

options = parser.parse_args()

cloud = cloud_config.get_one_cloud(argparse=options)

Constructing a Connection object

If what you want to do is get an openstack.connection.Connection and you want it to do all the normal things related to clouds.yaml, OS_ environment variables, a helper function is provided. The following will get you a fully configured openstacksdk instance.

import openstack.config

conn = openstack.config.make_connection()

If you want to do the same thing but on a named cloud.

import openstack.config

conn = openstack.config.make_connection(cloud='mtvexx')

If you want to do the same thing but also support command line parsing.

import argparse

import openstack.config

conn = openstack.config.make_connection(options=argparse.ArgumentParser())

Constructing cloud objects

If what you want to do is get an opentack.cloud.openstackcloud.OpenStackCloud object, a helper function that honors clouds.yaml and OS_ environment variables is provided. The following will get you a fully configured OpenStackCloud instance.

import openstack.config

cloud = openstack.config.make_cloud()

If you want to do the same thing but on a named cloud.

import openstack.config

cloud = openstack.config.make_cloud(cloud='mtvexx')

If you want to do the same thing but also support command line parsing.

import argparse

import openstack.config

cloud = openstack.config.make_cloud(options=argparse.ArgumentParser())

Constructing REST API Clients

What if you want to make direct REST calls via a Session interface? You're in luck. A similar interface is available as with openstacksdk and shade. The main difference is that you need to specify which service you want to talk to and make_rest_client will return you a keystoneauth Session object that is mounted on the endpoint for the service you're looking for.

import openstack.config

session = openstack.config.make_rest_client('compute', cloud='vexxhost')

response = session.get('/servers')
server_list = response.json()['servers']