# Copyright (C) 2014 Vaidas Jablonskis
#
# Author: Vaidas Jablonskis <jablonskis@gmail.com>
#
# This file is part of cloud-init. See LICENSE file for license information.

import datetime
import httpretty
import json
import re
from unittest import mock
from urllib.parse import urlparse

from base64 import b64encode, b64decode

from cloudinit import distros
from cloudinit import helpers
from cloudinit import settings
from cloudinit.sources import DataSourceGCE

from tests.unittests import helpers as test_helpers


GCE_META = {
    'instance/id': '123',
    'instance/zone': 'foo/bar',
    'instance/hostname': 'server.project-foo.local',
}

GCE_META_PARTIAL = {
    'instance/id': '1234',
    'instance/hostname': 'server.project-bar.local',
    'instance/zone': 'bar/baz',
}

GCE_META_ENCODING = {
    'instance/id': '12345',
    'instance/hostname': 'server.project-baz.local',
    'instance/zone': 'baz/bang',
    'instance/attributes': {
        'user-data': b64encode(b'#!/bin/echo baz\n').decode('utf-8'),
        'user-data-encoding': 'base64',
    }
}

GCE_USER_DATA_TEXT = {
    'instance/id': '12345',
    'instance/hostname': 'server.project-baz.local',
    'instance/zone': 'baz/bang',
    'instance/attributes': {
        'user-data': '#!/bin/sh\necho hi mom\ntouch /run/up-now\n',
    }
}

HEADERS = {'Metadata-Flavor': 'Google'}
MD_URL_RE = re.compile(
    r'http://metadata.google.internal/computeMetadata/v1/.*')
GUEST_ATTRIBUTES_URL = ('http://metadata.google.internal/computeMetadata/'
                        'v1/instance/guest-attributes/hostkeys/')


def _set_mock_metadata(gce_meta=None):
    if gce_meta is None:
        gce_meta = GCE_META

    def _request_callback(method, uri, headers):
        url_path = urlparse(uri).path
        if url_path.startswith('/computeMetadata/v1/'):
            path = url_path.split('/computeMetadata/v1/')[1:][0]
            recursive = path.endswith('/')
            path = path.rstrip('/')
        else:
            path = None
        if path in gce_meta:
            response = gce_meta.get(path)
            if recursive:
                response = json.dumps(response)
            return (200, headers, response)
        else:
            return (404, headers, '')

    # reset is needed. https://github.com/gabrielfalcao/HTTPretty/issues/316
    httpretty.register_uri(httpretty.GET, MD_URL_RE, body=_request_callback)


@httpretty.activate
class TestDataSourceGCE(test_helpers.HttprettyTestCase):

    def _make_distro(self, dtype, def_user=None):
        cfg = dict(settings.CFG_BUILTIN)
        cfg['system_info']['distro'] = dtype
        paths = helpers.Paths(cfg['system_info']['paths'])
        distro_cls = distros.fetch(dtype)
        if def_user:
            cfg['system_info']['default_user'] = def_user.copy()
        distro = distro_cls(dtype, cfg['system_info'], paths)
        return distro

    def setUp(self):
        tmp = self.tmp_dir()
        self.ds = DataSourceGCE.DataSourceGCE(
            settings.CFG_BUILTIN, None,
            helpers.Paths({'run_dir': tmp}))
        ppatch = self.m_platform_reports_gce = mock.patch(
            'cloudinit.sources.DataSourceGCE.platform_reports_gce')
        self.m_platform_reports_gce = ppatch.start()
        self.m_platform_reports_gce.return_value = True
        self.addCleanup(ppatch.stop)
        self.add_patch('time.sleep', 'm_sleep')  # just to speed up tests
        super(TestDataSourceGCE, self).setUp()

    def test_connection(self):
        _set_mock_metadata()
        success = self.ds.get_data()
        self.assertTrue(success)

        req_header = httpretty.last_request().headers
        for header_name, expected_value in HEADERS.items():
            self.assertEqual(expected_value, req_header.get(header_name))

    def test_metadata(self):
        # UnicodeDecodeError if set to ds.userdata instead of userdata_raw
        meta = GCE_META.copy()
        meta['instance/attributes/user-data'] = b'/bin/echo \xff\n'

        _set_mock_metadata()
        self.ds.get_data()

        shostname = GCE_META.get('instance/hostname').split('.')[0]
        self.assertEqual(shostname,
                         self.ds.get_hostname())

        self.assertEqual(GCE_META.get('instance/id'),
                         self.ds.get_instance_id())

        self.assertEqual(GCE_META.get('instance/attributes/user-data'),
                         self.ds.get_userdata_raw())

    # test partial metadata (missing user-data in particular)
    def test_metadata_partial(self):
        _set_mock_metadata(GCE_META_PARTIAL)
        self.ds.get_data()

        self.assertEqual(GCE_META_PARTIAL.get('instance/id'),
                         self.ds.get_instance_id())

        shostname = GCE_META_PARTIAL.get('instance/hostname').split('.')[0]
        self.assertEqual(shostname, self.ds.get_hostname())

    def test_userdata_no_encoding(self):
        """check that user-data is read."""
        _set_mock_metadata(GCE_USER_DATA_TEXT)
        self.ds.get_data()
        self.assertEqual(
            GCE_USER_DATA_TEXT['instance/attributes']['user-data'].encode(),
            self.ds.get_userdata_raw())

    def test_metadata_encoding(self):
        """user-data is base64 encoded if user-data-encoding is 'base64'."""
        _set_mock_metadata(GCE_META_ENCODING)
        self.ds.get_data()

        instance_data = GCE_META_ENCODING.get('instance/attributes')
        decoded = b64decode(instance_data.get('user-data'))
        self.assertEqual(decoded, self.ds.get_userdata_raw())

    def test_missing_required_keys_return_false(self):
        for required_key in ['instance/id', 'instance/zone',
                             'instance/hostname']:
            meta = GCE_META_PARTIAL.copy()
            del meta[required_key]
            _set_mock_metadata(meta)
            self.assertEqual(False, self.ds.get_data())
            httpretty.reset()

    def test_no_ssh_keys_metadata(self):
        _set_mock_metadata()
        self.ds.get_data()
        self.assertEqual([], self.ds.get_public_ssh_keys())

    def test_cloudinit_ssh_keys(self):
        valid_key = 'ssh-rsa VALID {0}'
        invalid_key = 'ssh-rsa INVALID {0}'
        project_attributes = {
            'sshKeys': '\n'.join([
                'cloudinit:{0}'.format(valid_key.format(0)),
                'user:{0}'.format(invalid_key.format(0)),
            ]),
            'ssh-keys': '\n'.join([
                'cloudinit:{0}'.format(valid_key.format(1)),
                'user:{0}'.format(invalid_key.format(1)),
            ]),
        }
        instance_attributes = {
            'ssh-keys': '\n'.join([
                'cloudinit:{0}'.format(valid_key.format(2)),
                'user:{0}'.format(invalid_key.format(2)),
            ]),
            'block-project-ssh-keys': 'False',
        }

        meta = GCE_META.copy()
        meta['project/attributes'] = project_attributes
        meta['instance/attributes'] = instance_attributes

        _set_mock_metadata(meta)
        self.ds.get_data()

        expected = [valid_key.format(key) for key in range(3)]
        self.assertEqual(set(expected), set(self.ds.get_public_ssh_keys()))

    @mock.patch("cloudinit.sources.DataSourceGCE.ug_util")
    def test_default_user_ssh_keys(self, mock_ug_util):
        mock_ug_util.normalize_users_groups.return_value = None, None
        mock_ug_util.extract_default.return_value = 'ubuntu', None
        ubuntu_ds = DataSourceGCE.DataSourceGCE(
            settings.CFG_BUILTIN, self._make_distro('ubuntu'),
            helpers.Paths({'run_dir': self.tmp_dir()}))

        valid_key = 'ssh-rsa VALID {0}'
        invalid_key = 'ssh-rsa INVALID {0}'
        project_attributes = {
            'sshKeys': '\n'.join([
                'ubuntu:{0}'.format(valid_key.format(0)),
                'user:{0}'.format(invalid_key.format(0)),
            ]),
            'ssh-keys': '\n'.join([
                'ubuntu:{0}'.format(valid_key.format(1)),
                'user:{0}'.format(invalid_key.format(1)),
            ]),
        }
        instance_attributes = {
            'ssh-keys': '\n'.join([
                'ubuntu:{0}'.format(valid_key.format(2)),
                'user:{0}'.format(invalid_key.format(2)),
            ]),
            'block-project-ssh-keys': 'False',
        }

        meta = GCE_META.copy()
        meta['project/attributes'] = project_attributes
        meta['instance/attributes'] = instance_attributes

        _set_mock_metadata(meta)
        ubuntu_ds.get_data()

        expected = [valid_key.format(key) for key in range(3)]
        self.assertEqual(set(expected), set(ubuntu_ds.get_public_ssh_keys()))

    def test_instance_ssh_keys_override(self):
        valid_key = 'ssh-rsa VALID {0}'
        invalid_key = 'ssh-rsa INVALID {0}'
        project_attributes = {
            'sshKeys': 'cloudinit:{0}'.format(invalid_key.format(0)),
            'ssh-keys': 'cloudinit:{0}'.format(invalid_key.format(1)),
        }
        instance_attributes = {
            'sshKeys': 'cloudinit:{0}'.format(valid_key.format(0)),
            'ssh-keys': 'cloudinit:{0}'.format(valid_key.format(1)),
            'block-project-ssh-keys': 'False',
        }

        meta = GCE_META.copy()
        meta['project/attributes'] = project_attributes
        meta['instance/attributes'] = instance_attributes

        _set_mock_metadata(meta)
        self.ds.get_data()

        expected = [valid_key.format(key) for key in range(2)]
        self.assertEqual(set(expected), set(self.ds.get_public_ssh_keys()))

    def test_block_project_ssh_keys_override(self):
        valid_key = 'ssh-rsa VALID {0}'
        invalid_key = 'ssh-rsa INVALID {0}'
        project_attributes = {
            'sshKeys': 'cloudinit:{0}'.format(invalid_key.format(0)),
            'ssh-keys': 'cloudinit:{0}'.format(invalid_key.format(1)),
        }
        instance_attributes = {
            'ssh-keys': 'cloudinit:{0}'.format(valid_key.format(0)),
            'block-project-ssh-keys': 'True',
        }

        meta = GCE_META.copy()
        meta['project/attributes'] = project_attributes
        meta['instance/attributes'] = instance_attributes

        _set_mock_metadata(meta)
        self.ds.get_data()

        expected = [valid_key.format(0)]
        self.assertEqual(set(expected), set(self.ds.get_public_ssh_keys()))

    def test_only_last_part_of_zone_used_for_availability_zone(self):
        _set_mock_metadata()
        r = self.ds.get_data()
        self.assertEqual(True, r)
        self.assertEqual('bar', self.ds.availability_zone)

    @mock.patch("cloudinit.sources.DataSourceGCE.GoogleMetadataFetcher")
    def test_get_data_returns_false_if_not_on_gce(self, m_fetcher):
        self.m_platform_reports_gce.return_value = False
        ret = self.ds.get_data()
        self.assertEqual(False, ret)
        m_fetcher.assert_not_called()

    def test_has_expired(self):

        def _get_timestamp(days):
            format_str = '%Y-%m-%dT%H:%M:%S+0000'
            today = datetime.datetime.now()
            timestamp = today + datetime.timedelta(days=days)
            return timestamp.strftime(format_str)

        past = _get_timestamp(-1)
        future = _get_timestamp(1)
        ssh_keys = {
            None: False,
            '': False,
            'Invalid': False,
            'user:ssh-rsa key user@domain.com': False,
            'user:ssh-rsa key google {"expireOn":"%s"}' % past: False,
            'user:ssh-rsa key google-ssh': False,
            'user:ssh-rsa key google-ssh {invalid:json}': False,
            'user:ssh-rsa key google-ssh {"userName":"user"}': False,
            'user:ssh-rsa key google-ssh {"expireOn":"invalid"}': False,
            'user:xyz key google-ssh {"expireOn":"%s"}' % future: False,
            'user:xyz key google-ssh {"expireOn":"%s"}' % past: True,
        }

        for key, expired in ssh_keys.items():
            self.assertEqual(DataSourceGCE._has_expired(key), expired)

    def test_parse_public_keys_non_ascii(self):
        public_key_data = [
            'cloudinit:rsa ssh-ke%s invalid' % chr(165),
            'use%sname:rsa ssh-key' % chr(174),
            'cloudinit:test 1',
            'default:test 2',
            'user:test 3',
        ]
        expected = ['test 1', 'test 2']
        found = DataSourceGCE._parse_public_keys(
            public_key_data, default_user='default')
        self.assertEqual(sorted(found), sorted(expected))

    @mock.patch("cloudinit.url_helper.readurl")
    def test_publish_host_keys(self, m_readurl):
        hostkeys = [('ssh-rsa', 'asdfasdf'),
                    ('ssh-ed25519', 'qwerqwer')]
        readurl_expected_calls = [
            mock.call(check_status=False, data=b'asdfasdf', headers=HEADERS,
                      request_method='PUT',
                      url='%s%s' % (GUEST_ATTRIBUTES_URL, 'ssh-rsa')),
            mock.call(check_status=False, data=b'qwerqwer', headers=HEADERS,
                      request_method='PUT',
                      url='%s%s' % (GUEST_ATTRIBUTES_URL, 'ssh-ed25519')),
        ]
        self.ds.publish_host_keys(hostkeys)
        m_readurl.assert_has_calls(readurl_expected_calls, any_order=True)

    @mock.patch(
        "cloudinit.sources.DataSourceGCE.EphemeralDHCPv4",
        autospec=True,
    )
    @mock.patch(
        "cloudinit.sources.DataSourceGCE.DataSourceGCELocal.fallback_interface"
    )
    def test_local_datasource_uses_ephemeral_dhcp(self, _m_fallback, m_dhcp):
        _set_mock_metadata()
        ds = DataSourceGCE.DataSourceGCELocal(
            sys_cfg={}, distro=None, paths=None
        )
        ds._get_data()
        assert m_dhcp.call_count == 1

    @mock.patch(
        "cloudinit.sources.DataSourceGCE.EphemeralDHCPv4",
        autospec=True,
    )
    def test_datasource_doesnt_use_ephemeral_dhcp(self, m_dhcp):
        _set_mock_metadata()
        ds = DataSourceGCE.DataSourceGCE(sys_cfg={}, distro=None, paths=None)
        ds._get_data()
        assert m_dhcp.call_count == 0

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