Flavio Percoco be666ff985 Add docs for Client instances
This patch documents the basic usage of `Client` instances. It does not
provide a detailed documentation about the methods exposed but a high
level documentation of what the recommended way to access these
resources is.

The current version refers to sections like 'core API', 'config' and
others that haven't been documented yet. Once they will be, proper links
to those sections will be added here.

Change-Id: I705498b8e4c19c75c9697419d1fd90c9a9ae40b9
2014-10-23 22:27:19 +02:00

83 lines
2.9 KiB
Python

# Copyright (c) 2013 Red Hat, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
# implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
A `Client` is a high-level abstraction on top of Zaqar features. It
exposes the server features with an object-oriented interface, which
encourages dot notation and automatic, but lazy, resources
allocation. A `Client` allows you to control everything, from public
interfaces to admin endpoints.
To create a `Client` instance, you supply an url pointing to the
server and a version number::
from zaqarclient.queues import client
cli = client.Client(\'http://zaqar.example.com:8888/\', version=1.1)
which will load the appropriate client based on the specified
version. Optionally, you can also supply a config dictionary::
from zaqarclient.queues import client
cli = client.Client(\'http://zaqar.example.com:8888/\',
version=1.1, conf={})
The arguments passed to this function will be passed to the client
instances as well.
It's recommended to use `Client` instances instead of accessing the
lower level API as it has been designed to ease the interaction with
the server and it gives enough control for the most common cases.
A simple example for accessing an existing queue through a client
instance - based on the API v1.1 - would look like::
from zaqarclient.queues import client
cli = client.Client(\'http://zaqar.example.com:8888/\', version=1.1)
queue = cli.queue(\'my_queue\')
Through the queue instance will be then possible to access all the
features associated with the queue itself like posting messages,
getting message and deleting messages.
As mentioned previously in this documentation, a client instance
allows you to also access admin endpoints, for example::
from zaqarclient.queues import client
cli = client.Client(\'http://zaqar.example.com:8888/\', version=1.1)
flavor = cli.flavor(\'tasty\',
pool=\'my-pool-group\',
auto_create=True)
flavor.delete()
`Client` uses the lower-level API to access the server, which means
anything you can do with this client instance can be done by accessing
the underlying API, although not recommended.
"""
from zaqarclient import errors
from zaqarclient.queues.v1 import client as cv1
_CLIENTS = {1: cv1.Client,
1.1: cv1.Client}
def Client(url=None, version=None, conf=None):
try:
return _CLIENTS[version](url, version, conf)
except KeyError:
raise errors.ZaqarError('Unknown client version')