python-openstackclient/examples/common.py
Steve Martinelli 126b2c5436 Add an API example base and functional test base
Add examples/common.py, which is a basic common setup that mimics OSC's
configuration options and logging without the rest of the CLI.

Also add the functional test tooling for examples to prevent bit rot.

Co-Authored-By: Dean Troyer <dtroyer@gmail.com>
Change-Id: Ie92b675eafd93482ddc9a8ce0b0588e23ed50c35
2014-11-15 16:29:08 -06:00

265 lines
7.1 KiB
Python
Executable File

#!/usr/bin/env python
# common.py - Common bits for API examples
# 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.
"""
API Examples
This is a collection of common functions used by the example scripts.
It may also be run directly as a script to do basic testing of itself.
common.object_parser() provides the common set of command-line arguments
used in the library CLIs for setting up authentication. This should make
playing with the example scripts against a running OpenStack simpler.
common.configure_logging() provides the same basic logging control as
the OSC shell.
common.make_session() does the minimal loading of a Keystone authentication
plugin and creates a Keystone client Session.
"""
import argparse
import logging
import os
import sys
import traceback
from keystoneclient import session as ksc_session
from openstackclient.api import auth
CONSOLE_MESSAGE_FORMAT = '%(levelname)s: %(name)s %(message)s'
DEFAULT_VERBOSE_LEVEL = 1
USER_AGENT = 'osc-examples'
PARSER_DESCRIPTION = 'A demonstration framework'
DEFAULT_IDENTITY_API_VERSION = '2.0'
_logger = logging.getLogger(__name__)
# --debug sets this True
dump_stack_trace = False
# Generally useful stuff often found in a utils module
def env(*vars, **kwargs):
"""Search for the first defined of possibly many env vars
Returns the first environment variable defined in vars, or
returns the default defined in kwargs.
"""
for v in vars:
value = os.environ.get(v, None)
if value:
return value
return kwargs.get('default', '')
# Common Example functions
def base_parser(parser):
"""Set up some of the common CLI options
These are the basic options that match the library CLIs so
command-line/environment setups for those also work with these
demonstration programs.
"""
# Global arguments
parser.add_argument(
'--os-url',
metavar='<url>',
default=env('OS_URL'),
help='Defaults to env[OS_URL]',
)
parser.add_argument(
'--os-region-name',
metavar='<auth-region-name>',
default=env('OS_REGION_NAME'),
help='Authentication region name (Env: OS_REGION_NAME)',
)
parser.add_argument(
'--os-cacert',
metavar='<ca-bundle-file>',
default=env('OS_CACERT'),
help='CA certificate bundle file (Env: OS_CACERT)',
)
verify_group = parser.add_mutually_exclusive_group()
verify_group.add_argument(
'--verify',
action='store_true',
help='Verify server certificate (default)',
)
verify_group.add_argument(
'--insecure',
action='store_true',
help='Disable server certificate verification',
)
parser.add_argument(
'--timing',
default=False,
action='store_true',
help="Print API call timing info",
)
parser.add_argument(
'-v', '--verbose',
action='count',
dest='verbose_level',
default=1,
help='Increase verbosity of output. Can be repeated.',
)
parser.add_argument(
'--debug',
default=False,
action='store_true',
help='show tracebacks on errors',
)
parser.add_argument(
'rest',
nargs='*',
help='the rest of the args',
)
return parser
def configure_logging(opts):
"""Typical app logging setup
Based on OSC/cliff
"""
global dump_stack_trace
root_logger = logging.getLogger('')
# Requests logs some stuff at INFO that we don't want
# unless we have DEBUG
requests_log = logging.getLogger("requests")
requests_log.setLevel(logging.ERROR)
# Other modules we don't want DEBUG output for so
# don't reset them below
iso8601_log = logging.getLogger("iso8601")
iso8601_log.setLevel(logging.ERROR)
# Always send higher-level messages to the console via stderr
console = logging.StreamHandler(sys.stderr)
formatter = logging.Formatter(CONSOLE_MESSAGE_FORMAT)
console.setFormatter(formatter)
root_logger.addHandler(console)
# Set logging to the requested level
dump_stack_trace = False
if opts.verbose_level == 0:
# --quiet
root_logger.setLevel(logging.ERROR)
elif opts.verbose_level == 1:
# This is the default case, no --debug, --verbose or --quiet
root_logger.setLevel(logging.WARNING)
elif opts.verbose_level == 2:
# One --verbose
root_logger.setLevel(logging.INFO)
elif opts.verbose_level >= 3:
# Two or more --verbose
root_logger.setLevel(logging.DEBUG)
requests_log.setLevel(logging.DEBUG)
if opts.debug:
# --debug forces traceback
dump_stack_trace = True
root_logger.setLevel(logging.DEBUG)
requests_log.setLevel(logging.DEBUG)
return
def make_session(opts, **kwargs):
"""Create our base session using simple auth from ksc plugins
The arguments required in opts varies depending on the auth plugin
that is used. This example assumes Identity v2 will be used
and selects token auth if both os_url and os_token have been
provided, otherwise it uses password.
:param Namespace opts:
A parser options Namespace containing the authentication
options to be used
:param dict kwargs:
Additional options passed directly to Session constructor
"""
# If no auth type is named by the user, select one based on
# the supplied options
auth_plugin_name = auth.select_auth_plugin(opts)
(auth_plugin, auth_params) = auth.build_auth_params(
auth_plugin_name,
opts,
)
auth_p = auth_plugin.load_from_options(**auth_params)
session = ksc_session.Session(
auth=auth_p,
**kwargs
)
return session
# Top-level functions
def run(opts):
"""Default run command"""
# Do some basic testing here
sys.stdout.write("Default run command\n")
sys.stdout.write("Verbose level: %s\n" % opts.verbose_level)
sys.stdout.write("Debug: %s\n" % opts.debug)
sys.stdout.write("dump_stack_trace: %s\n" % dump_stack_trace)
def setup():
"""Parse command line and configure logging"""
opts = base_parser(
auth.build_auth_plugins_option_parser(
argparse.ArgumentParser(description='Object API Example')
)
).parse_args()
configure_logging(opts)
return opts
def main(opts, run):
try:
return run(opts)
except Exception as e:
if dump_stack_trace:
_logger.error(traceback.format_exc(e))
else:
_logger.error('Exception raised: ' + str(e))
return 1
if __name__ == "__main__":
opts = setup()
sys.exit(main(opts, run))