python-glanceclient/glanceclient/shell.py

# Copyright 2012 OpenStack LLC.
# All Rights Reserved.
#
#    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.

"""
Command-line interface to the OpenStack Images API.
"""

import argparse
import httplib2
import re
import sys

from keystoneclient.v2_0 import client as ksclient

import glanceclient.client
from glanceclient.common import exceptions as exc
from glanceclient.common import utils


class OpenStackImagesShell(object):

    def get_base_parser(self):
        parser = argparse.ArgumentParser(
            prog='glance',
            description=__doc__.strip(),
            epilog='See "glance help COMMAND" '
                   'for help on a specific command.',
            add_help=False,
            formatter_class=HelpFormatter,
        )

        # Global arguments
        parser.add_argument('-h', '--help',
            action='store_true',
            help=argparse.SUPPRESS,
        )

        parser.add_argument('--debug',
            default=False,
            action='store_true',
            help=argparse.SUPPRESS)

        parser.add_argument('--insecure',
            default=False,
            action='store_true',
            help=argparse.SUPPRESS)

        parser.add_argument('--os-username',
            default=utils.env('OS_USERNAME'),
            help='Defaults to env[OS_USERNAME]')

        parser.add_argument('--os-password',
            default=utils.env('OS_PASSWORD'),
            help='Defaults to env[OS_PASSWORD]')

        parser.add_argument('--os-tenant-id',
            default=utils.env('OS_TENANT_ID'),
            help='Defaults to env[OS_TENANT_ID]')

        parser.add_argument('--os-tenant-name',
            default=utils.env('OS_TENANT_NAME'),
            help='Defaults to env[OS_TENANT_NAME]')

        parser.add_argument('--os-auth-url',
            default=utils.env('OS_AUTH_URL'),
            help='Defaults to env[OS_AUTH_URL]')

        parser.add_argument('--os-region-name',
            default=utils.env('OS_REGION_NAME'),
            help='Defaults to env[OS_REGION_NAME]')

        parser.add_argument('--os-auth-token',
            default=utils.env('OS_AUTH_TOKEN'),
            help='Defaults to env[OS_AUTH_TOKEN]')

        parser.add_argument('--os-image-url',
            default=utils.env('OS_IMAGE_URL'),
            help='Defaults to env[OS_IMAGE_URL]')

        parser.add_argument('--os-image-api-version',
            default=utils.env('OS_IMAGE_API_VERSION', default='1'),
            help='Defaults to env[OS_IMAGE_API_VERSION] or 1')

        parser.add_argument('--os-service-type',
            default=utils.env('OS_SERVICE_TYPE'),
            help='Defaults to env[OS_SERVICE_TYPE]')

        parser.add_argument('--os-endpoint-type',
            default=utils.env('OS_ENDPOINT_TYPE'),
            help='Defaults to env[OS_ENDPOINT_TYPE]')

        return parser

    def get_subcommand_parser(self, version):
        parser = self.get_base_parser()

        self.subcommands = {}
        subparsers = parser.add_subparsers(metavar='<subcommand>')
        submodule = utils.import_versioned_module(version, 'shell')
        self._find_actions(subparsers, submodule)
        self._find_actions(subparsers, self)

        return parser

    def _find_actions(self, subparsers, actions_module):
        for attr in (a for a in dir(actions_module) if a.startswith('do_')):
            # I prefer to be hypen-separated instead of underscores.
            command = attr[3:].replace('_', '-')
            callback = getattr(actions_module, attr)
            desc = callback.__doc__ or ''
            help = desc.strip().split('\n')[0]
            arguments = getattr(callback, 'arguments', [])

            subparser = subparsers.add_parser(command,
                help=help,
                description=desc,
                add_help=False,
                formatter_class=HelpFormatter
            )
            subparser.add_argument('-h', '--help',
                action='help',
                help=argparse.SUPPRESS,
            )
            self.subcommands[command] = subparser
            for (args, kwargs) in arguments:
                subparser.add_argument(*args, **kwargs)
            subparser.set_defaults(func=callback)

    # TODO(dtroyer): move this into the common client support?
    # Compatibility check to remove API version as the trailing component
    # in a service endpoint; also removes a trailing '/'
    def _strip_version(self, endpoint):
        """Strip a version from the last component of an endpoint if present"""

        # Get rid of trailing '/' if present
        if endpoint.endswith('/'):
            endpoint = endpoint[:-1]
        url_bits = endpoint.split('/')
        # regex to match 'v1' or 'v2.0' etc
        if re.match('v\d+\.?\d*', url_bits[-1]):
            endpoint = '/'.join(url_bits[:-1])
        return endpoint

    def _authenticate(self, **kwargs):
        """Get an endpoint and auth token from Keystone.

        :param username: name of user
        :param password: user's password
        :param tenant_id: unique identifier of tenant
        :param tenant_name: name of tenant
        :param auth_url: endpoint to authenticate against
        """
        _ksclient = ksclient.Client(username=kwargs.get('username'),
                                    password=kwargs.get('password'),
                                    tenant_id=kwargs.get('tenant_id'),
                                    tenant_name=kwargs.get('tenant_name'),
                                    auth_url=kwargs.get('auth_url'))
        service_type = kwargs.get('service_type') or 'image'
        endpoint_type = kwargs.get('endpoint_type') or 'publicURL'
        endpoint = _ksclient.service_catalog.url_for(
                             service_type=service_type,
                             endpoint_type=endpoint_type)
        endpoint = self._strip_version(endpoint)
        return (endpoint, _ksclient.auth_token)

    def main(self, argv):
        # Parse args once to find version
        parser = self.get_base_parser()
        (options, args) = parser.parse_known_args(argv)

        # build available subcommands based on version
        api_version = options.os_image_api_version
        subcommand_parser = self.get_subcommand_parser(api_version)
        self.parser = subcommand_parser

        # Handle top-level --help/-h before attempting to parse
        # a command off the command line
        if options.help or not argv:
            self.do_help(options)
            return 0

        # Parse args again and call whatever callback was selected
        args = subcommand_parser.parse_args(argv)

        # Deal with global arguments
        if args.debug:
            httplib2.debuglevel = 1

        # Short-circuit and deal with help command right away.
        if args.func == self.do_help:
            self.do_help(args)
            return 0

        auth_reqd = (utils.is_authentication_required(args.func) and
                     not (args.os_auth_token and args.os_image_url))

        if not auth_reqd:
            endpoint = args.os_image_url
            token = args.os_auth_token
        else:
            if not args.os_username:
                raise exc.CommandError("You must provide a username via"
                        " either --os-username or env[OS_USERNAME]")

            if not args.os_password:
                raise exc.CommandError("You must provide a password via"
                        " either --os-password or env[OS_PASSWORD]")

            if not (args.os_tenant_id or args.os_tenant_name):
                raise exc.CommandError("You must provide a tenant_id via"
                        " either --os-tenant-id or via env[OS_TENANT_ID]")

            if not args.os_auth_url:
                raise exc.CommandError("You must provide an auth url via"
                        " either --os-auth-url or via env[OS_AUTH_URL]")
            kwargs = {
                'username': args.os_username,
                'password': args.os_password,
                'tenant_id': args.os_tenant_id,
                'tenant_name': args.os_tenant_name,
                'auth_url': args.os_auth_url,
                'service_type': args.os_service_type,
                'endpoint_type': args.os_endpoint_type
            }
            endpoint, token = self._authenticate(**kwargs)

        image_service = glanceclient.client.Client(
                api_version, endpoint, token, insecure=args.insecure)

        try:
            args.func(image_service, args)
        except exc.Unauthorized:
            raise exc.CommandError("Invalid OpenStack Identity credentials.")
        except exc.AuthorizationFailure:
            raise exc.CommandError("Unable to authorize user")

    @utils.arg('command', metavar='<subcommand>', nargs='?',
               help='Display help for <subcommand>')
    def do_help(self, args):
        """
        Display help about this program or one of its subcommands.
        """
        if getattr(args, 'command', None):
            if args.command in self.subcommands:
                self.subcommands[args.command].print_help()
            else:
                raise exc.CommandError("'%s' is not a valid subcommand" %
                                       args.command)
        else:
            self.parser.print_help()


class HelpFormatter(argparse.HelpFormatter):
    def start_section(self, heading):
        # Title-case the headings
        heading = '%s%s' % (heading[0].upper(), heading[1:])
        super(HelpFormatter, self).start_section(heading)


def main():
    try:
        OpenStackImagesShell().main(sys.argv[1:])

    except Exception, e:
        if httplib2.debuglevel == 1:
            raise
        else:
            print >> sys.stderr, e
        sys.exit(1)