# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright 2011 Piston Cloud Computing, Inc.
# 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.

"""Test of Policy Engine For Cinder"""

import os.path
import StringIO
import urllib2

from cinder.common import policy as common_policy
from cinder import context
from cinder import exception
from cinder import flags
import cinder.common.policy
from cinder import policy
from cinder import test
from cinder import utils

FLAGS = flags.FLAGS


class PolicyFileTestCase(test.TestCase):
    def setUp(self):
        super(PolicyFileTestCase, self).setUp()
        policy.reset()
        self.context = context.RequestContext('fake', 'fake')
        self.target = {}

    def tearDown(self):
        super(PolicyFileTestCase, self).tearDown()
        policy.reset()

    def test_modified_policy_reloads(self):
        with utils.tempdir() as tmpdir:
            tmpfilename = os.path.join(tmpdir, 'policy')
            self.flags(policy_file=tmpfilename)

            action = "example:test"
            with open(tmpfilename, "w") as policyfile:
                policyfile.write("""{"example:test": []}""")
            policy.enforce(self.context, action, self.target)
            with open(tmpfilename, "w") as policyfile:
                policyfile.write("""{"example:test": ["false:false"]}""")
            # NOTE(vish): reset stored policy cache so we don't have to
            # sleep(1)
            policy._POLICY_CACHE = {}
            self.assertRaises(exception.PolicyNotAuthorized, policy.enforce,
                              self.context, action, self.target)


class PolicyTestCase(test.TestCase):
    def setUp(self):
        super(PolicyTestCase, self).setUp()
        policy.reset()
        # NOTE(vish): preload rules to circumvent reloading from file
        policy.init()
        rules = {
            "true": [],
            "example:allowed": [],
            "example:denied": [["false:false"]],
            "example:get_http": [["http:http://www.example.com"]],
            "example:my_file": [["role:compute_admin"],
                                ["project_id:%(project_id)s"]],
            "example:early_and_fail": [["false:false", "rule:true"]],
            "example:early_or_success": [["rule:true"], ["false:false"]],
            "example:lowercase_admin": [["role:admin"], ["role:sysadmin"]],
            "example:uppercase_admin": [["role:ADMIN"], ["role:sysadmin"]],
        }
        # NOTE(vish): then overload underlying brain
        common_policy.set_brain(common_policy.HttpBrain(rules))
        self.context = context.RequestContext('fake', 'fake', roles=['member'])
        self.target = {}

    def tearDown(self):
        policy.reset()
        super(PolicyTestCase, self).tearDown()

    def test_enforce_nonexistent_action_throws(self):
        action = "example:noexist"
        self.assertRaises(exception.PolicyNotAuthorized, policy.enforce,
                          self.context, action, self.target)

    def test_enforce_bad_action_throws(self):
        action = "example:denied"
        self.assertRaises(exception.PolicyNotAuthorized, policy.enforce,
                          self.context, action, self.target)

    def test_enforce_good_action(self):
        action = "example:allowed"
        policy.enforce(self.context, action, self.target)

    def test_enforce_http_true(self):

        def fakeurlopen(url, post_data):
            return StringIO.StringIO("True")
        self.stubs.Set(urllib2, 'urlopen', fakeurlopen)
        action = "example:get_http"
        target = {}
        result = policy.enforce(self.context, action, target)
        self.assertEqual(result, None)

    def test_enforce_http_false(self):

        def fakeurlopen(url, post_data):
            return StringIO.StringIO("False")
        self.stubs.Set(urllib2, 'urlopen', fakeurlopen)
        action = "example:get_http"
        target = {}
        self.assertRaises(exception.PolicyNotAuthorized, policy.enforce,
                          self.context, action, target)

    def test_templatized_enforcement(self):
        target_mine = {'project_id': 'fake'}
        target_not_mine = {'project_id': 'another'}
        action = "example:my_file"
        policy.enforce(self.context, action, target_mine)
        self.assertRaises(exception.PolicyNotAuthorized, policy.enforce,
                          self.context, action, target_not_mine)

    def test_early_AND_enforcement(self):
        action = "example:early_and_fail"
        self.assertRaises(exception.PolicyNotAuthorized, policy.enforce,
                          self.context, action, self.target)

    def test_early_OR_enforcement(self):
        action = "example:early_or_success"
        policy.enforce(self.context, action, self.target)

    def test_ignore_case_role_check(self):
        lowercase_action = "example:lowercase_admin"
        uppercase_action = "example:uppercase_admin"
        # NOTE(dprince) we mix case in the Admin role here to ensure
        # case is ignored
        admin_context = context.RequestContext('admin',
                                                'fake',
                                                roles=['AdMiN'])
        policy.enforce(admin_context, lowercase_action, self.target)
        policy.enforce(admin_context, uppercase_action, self.target)


class DefaultPolicyTestCase(test.TestCase):

    def setUp(self):
        super(DefaultPolicyTestCase, self).setUp()
        policy.reset()
        policy.init()

        self.rules = {
            "default": [],
            "example:exist": [["false:false"]]
        }

        self._set_brain('default')

        self.context = context.RequestContext('fake', 'fake')

    def _set_brain(self, default_rule):
        brain = cinder.common.policy.HttpBrain(self.rules, default_rule)
        cinder.common.policy.set_brain(brain)

    def tearDown(self):
        super(DefaultPolicyTestCase, self).tearDown()
        policy.reset()

    def test_policy_called(self):
        self.assertRaises(exception.PolicyNotAuthorized, policy.enforce,
                self.context, "example:exist", {})

    def test_not_found_policy_calls_default(self):
        policy.enforce(self.context, "example:noexist", {})

    def test_default_not_found(self):
        self._set_brain("default_noexist")
        self.assertRaises(exception.PolicyNotAuthorized, policy.enforce,
                self.context, "example:noexist", {})
