azure-functions-python-library/tests/test_servicebus.py

# Copyright (c) Microsoft Corporation. All rights reserved.
# Licensed under the MIT License.

from typing import Dict, List
import json
import unittest
from datetime import datetime, timedelta, date

import azure.functions as func
import azure.functions.servicebus as azf_sb
from azure.functions import meta

from .testutils import CollectionBytes, CollectionString, CollectionSint64


class TestServiceBus(unittest.TestCase):
    MOCKED_CONTENT_TYPE = 'application/json'
    MOCKED_CORROLATION_ID = '87c66eaf88e84119b66a26278a7b4149'
    MOCKED_DEADLETTER_ERROR_DESCRIPTION = \
        'mocked_dead_letter_error_description'
    MOCKED_DEADLETTER_REASON = 'mocked_dead_letter_reason'
    MOCKED_DEADLETTER_SOURCE = 'mocked_dead_letter_source'
    MOCKED_DELIVERY_COUNT = 571
    MOCKED_ENQUEUED_SEQUENCE_NUMBER = 15
    MOCKED_ENQUEUE_TIME_UTC = datetime.utcnow()
    MOCKED_EXPIRY_AT_UTC = datetime.utcnow()
    MOCKED_LABEL = 'mocked_label'
    MOCKED_LOCKED_UNTIL = datetime.utcnow()
    MOCKED_LOCK_TOKEN = '87931fd2-39f4-415a-9fdc-adfdcbed3148'
    MOCKED_MESSAGE_ID = 'abcee18397398d93891830a0aac89eed'
    MOCKED_MESSAGE_ID_A = 'aaaaa18397398d93891830a0aac89eed'
    MOCKED_MESSAGE_ID_B = 'bbbbb18397398d93891830a0aac89eed'
    MOCKED_MESSAGE_ID_C = 'ccccc18397398d93891830a0aac89eed'
    MOCKED_PARTITION_KEY = 'mocked_partition_key'
    MOCKED_REPLY_TO = 'mocked_reply_to'
    MOCKED_REPLY_TO_SESSION_ID = 'mocked_reply_to_session_id'
    MOCKED_SCHEDULED_ENQUEUE_TIME_UTC = datetime.utcnow()
    MOCKED_SEQUENCE_NUMBER = 38291
    MOCKED_SESSION_ID = 'mocked_session_id'
    MOCKED_STATE = 1
    MOCKED_SUBJECT = 'mocked_subject'
    MOCKED_TIME_TO_LIVE = '11:22:33'
    MOCKED_TIME_TO_LIVE_TIMEDELTA = timedelta(hours=11, minutes=22, seconds=33)
    MOCKED_TO = 'mocked_to'
    MOCKED_TRANSACTION_PARTITION_KEY = 'mocked_transaction_partition_key'

    MOCKED_AZURE_PARTNER_ID = '6ceef68b-0794-45dd-bb2e-630748515552'

    def test_servicebusmessage_initialize_without_args(self):
        # given
        expected_body = b""
        expexceted_content_type = None
        expected_correlation_id = None

        # when
        test_sb_message = func.ServiceBusMessage()

        # then
        assert expected_body == test_sb_message.get_body()
        assert expexceted_content_type == test_sb_message.content_type
        assert expected_correlation_id == test_sb_message.correlation_id

    def test_servicebusmessage_initialize_all_arguments(self):
        # given
        expected_body: bytes = b"Body"
        expected_content_type: str = "Content Type"
        expected_correlation_id: str = "Correlation ID"

        # when
        test_sb_message = func.ServiceBusMessage(
            body=expected_body,
            content_type=expected_content_type,
            correlation_id=expected_correlation_id
        )

        # then
        assert expected_body == test_sb_message.get_body()
        assert expected_content_type == test_sb_message.content_type
        assert expected_correlation_id == test_sb_message.correlation_id
        self.assertDictEqual(test_sb_message.application_properties, {})
        self.assertIsNone(test_sb_message.dead_letter_error_description)
        self.assertIsNone(test_sb_message.dead_letter_reason)
        self.assertIsNone(test_sb_message.dead_letter_source)
        self.assertIsNone(test_sb_message.delivery_count)
        self.assertIsNone(test_sb_message.enqueued_sequence_number)
        self.assertIsNone(test_sb_message.enqueued_time_utc)
        self.assertIsNone(test_sb_message.expires_at_utc)
        self.assertIsNone(test_sb_message.expiration_time)
        self.assertIsNone(test_sb_message.label)
        self.assertIsNone(test_sb_message.locked_until)
        self.assertIsNone(test_sb_message.lock_token)
        assert "" == test_sb_message.message_id
        self.assertIsNone(test_sb_message.partition_key)
        self.assertIsNone(test_sb_message.reply_to)
        self.assertIsNone(test_sb_message.reply_to_session_id)
        self.assertIsNone(test_sb_message.scheduled_enqueue_time)
        self.assertIsNone(test_sb_message.scheduled_enqueue_time_utc)
        self.assertIsNone(test_sb_message.sequence_number)
        self.assertIsNone(test_sb_message.session_id)
        self.assertIsNone(test_sb_message.state)
        self.assertIsNone(test_sb_message.subject)
        self.assertIsNone(test_sb_message.time_to_live)
        self.assertIsNone(test_sb_message.to)
        self.assertIsNone(test_sb_message.transaction_partition_key)
        self.assertDictEqual(test_sb_message.user_properties, {})
        self.assertIsNone(test_sb_message.metadata)

    def test_servicebus_message_initialize_all_args(self):
        # given
        body = "body"
        trigger_metadata = "trigger metadata"
        application_properties = {"application": "properties"}
        content_type = "content type"
        correlation_id = "correlation id"
        dead_letter_error_description = "dead letter error description"
        dead_letter_reason = "dead letter reason"
        dead_letter_source = "dead letter source"
        delivery_count = 1
        enqueued_sequence_number = 1
        enqueued_time_utc = date(2022, 5, 1)
        expires_at_utc = date(2022, 5, 1)
        label = "label"
        locked_until = date(2022, 5, 1)
        lock_token = "lock token"
        message_id = "message id"
        partition_key = "partition key"
        reply_to = "reply to"
        reply_to_session_id = "reply to session id"
        scheduled_enqueue_time_utc = date(2022, 5, 1)
        sequence_number = 1
        session_id = "session id"
        state = 1
        subject = "subject"
        time_to_live = timedelta(hours=1)
        to = "to"
        transaction_partition_key = "transaction partition key"
        user_properties = {"user": "properties"}

        # when
        sb_message = azf_sb.ServiceBusMessage(
            body=body,
            trigger_metadata=trigger_metadata,
            application_properties=application_properties,
            content_type=content_type,
            correlation_id=correlation_id,
            dead_letter_error_description=dead_letter_error_description,
            dead_letter_reason=dead_letter_reason,
            dead_letter_source=dead_letter_source,
            delivery_count=delivery_count,
            enqueued_sequence_number=enqueued_sequence_number,
            enqueued_time_utc=enqueued_time_utc,
            expires_at_utc=expires_at_utc,
            label=label,
            locked_until=locked_until,
            lock_token=lock_token,
            message_id=message_id,
            partition_key=partition_key,
            reply_to=reply_to,
            reply_to_session_id=reply_to_session_id,
            scheduled_enqueue_time_utc=scheduled_enqueue_time_utc,
            sequence_number=sequence_number,
            session_id=session_id,
            state=state,
            subject=subject,
            time_to_live=time_to_live,
            to=to,
            transaction_partition_key=transaction_partition_key,
            user_properties=user_properties)

        # then
        self.assertEqual(sb_message.get_body(), body)
        self.assertEqual(sb_message.application_properties,
                         application_properties)
        self.assertEqual(sb_message.content_type, content_type)
        self.assertEqual(sb_message.correlation_id, correlation_id)
        self.assertEqual(sb_message.dead_letter_error_description,
                         dead_letter_error_description)
        self.assertEqual(sb_message.dead_letter_reason, dead_letter_reason)
        self.assertEqual(sb_message.dead_letter_source, dead_letter_source)
        self.assertEqual(sb_message.delivery_count, delivery_count)
        self.assertEqual(sb_message.enqueued_sequence_number,
                         enqueued_sequence_number)
        self.assertEqual(sb_message.enqueued_time_utc, enqueued_time_utc)
        self.assertEqual(sb_message.expires_at_utc, expires_at_utc)
        self.assertEqual(sb_message.label, label)
        self.assertEqual(sb_message.locked_until, locked_until)
        self.assertEqual(sb_message.lock_token, lock_token)
        self.assertEqual(sb_message.message_id, message_id)
        self.assertEqual(sb_message.partition_key, partition_key)
        self.assertEqual(sb_message.reply_to, reply_to)
        self.assertEqual(sb_message.reply_to_session_id, reply_to_session_id)
        self.assertEqual(sb_message.scheduled_enqueue_time_utc,
                         scheduled_enqueue_time_utc)
        self.assertEqual(sb_message.sequence_number, sequence_number)
        self.assertEqual(sb_message.session_id, session_id)
        self.assertEqual(sb_message.state, state)
        self.assertEqual(sb_message.subject, subject)
        self.assertEqual(sb_message.time_to_live, time_to_live)
        self.assertEqual(sb_message.to, to)
        self.assertEqual(sb_message.transaction_partition_key,
                         transaction_partition_key)
        self.assertEqual(sb_message.user_properties, user_properties)

    def test_abstract_servicebus_message(self):
        test_sb_message = func.ServiceBusMessage()
        abstract_sb_message = func._abc.ServiceBusMessage

        self.assertIsInstance(test_sb_message, abstract_sb_message)
        with self.assertRaises(TypeError):
            func._abc.ServiceBusMessage()

    def test_servicebus_input_type(self):
        check_input_type = (
            azf_sb.ServiceBusMessageInConverter.check_input_type_annotation
        )
        # Should accept a single service bus message as trigger input type
        self.assertTrue(check_input_type(func.ServiceBusMessage))

        # Should accept a multiple service bus message as trigger input type
        self.assertTrue(check_input_type(List[func.ServiceBusMessage]))

        # Should accept a message class derived from service bus
        class ServiceBusMessageChild(func.ServiceBusMessage):
            FOO = 'BAR'

        self.assertTrue(check_input_type(ServiceBusMessageChild))

        # Should be false if a message type does not match expectation
        self.assertFalse(check_input_type(func.EventHubEvent))
        self.assertFalse(check_input_type(str))
        self.assertFalse(check_input_type(type(None)))

    def test_servicebus_output_type(self):
        check_output_type = (
            azf_sb.ServiceBusMessageOutConverter.check_output_type_annotation
        )
        # Should accept bytes and string as trigger output type
        self.assertTrue(check_output_type(bytes))
        self.assertTrue(check_output_type(str))

        # Should reject if attempt to send a service bus message out
        self.assertFalse(check_output_type(func.ServiceBusMessage))

        # Should be false if a message type does not match expectation
        self.assertFalse(check_output_type(func.EventGridEvent))
        self.assertFalse(check_output_type(type(None)))

    def test_servicebus_data(self):
        servicebus_msg = azf_sb.ServiceBusMessageInConverter.decode(
            data=self._generate_single_servicebus_data(),
            trigger_metadata=self._generate_single_trigger_metadata())

        servicebus_data = servicebus_msg.get_body().decode('utf-8')
        self.assertEqual(servicebus_data, json.dumps({"lucky_number": 23}))

    def test_servicebus_non_existing_property(self):
        # The function should not fail even when property does not work
        msg = azf_sb.ServiceBusMessageInConverter.decode(
            data=self._generate_single_servicebus_data(),
            trigger_metadata={
                'MessageId': meta.Datum(self.MOCKED_MESSAGE_ID, 'string'),
                'UserProperties': meta.Datum('{ "UserId": 1 }', 'json')
            }
        )

        # Property that are not passed from extension should be None
        self.assertIsNone(msg.content_type)

        # Message id should always be available
        self.assertEqual(msg.message_id, self.MOCKED_MESSAGE_ID)

        # User property should always be available
        self.assertEqual(msg.user_properties['UserId'], 1)

    def test_servicebus_properties(self):
        # SystemProperties in metadata should propagate to class properties
        msg = azf_sb.ServiceBusMessageInConverter.decode(
            data=meta.Datum(b'body_bytes', 'bytes'),
            trigger_metadata=self._generate_single_trigger_metadata())

        self.assertEqual(msg.get_body(), b'body_bytes')

        # Test individual ServiceBus properties respectively
        self.assertEqual(msg.application_properties,
                         {'application': 'value'})
        self.assertEqual(msg.content_type,
                         self.MOCKED_CONTENT_TYPE)
        self.assertEqual(msg.correlation_id,
                         self.MOCKED_CORROLATION_ID)
        self.assertEqual(msg.dead_letter_error_description,
                         self.MOCKED_DEADLETTER_ERROR_DESCRIPTION)
        self.assertEqual(msg.dead_letter_reason, self.MOCKED_DEADLETTER_REASON)
        self.assertEqual(msg.dead_letter_source,
                         self.MOCKED_DEADLETTER_SOURCE)
        self.assertEqual(msg.enqueued_sequence_number,
                         self.MOCKED_ENQUEUED_SEQUENCE_NUMBER)
        self.assertEqual(msg.enqueued_time_utc,
                         self.MOCKED_ENQUEUE_TIME_UTC)
        self.assertEqual(msg.expires_at_utc,
                         self.MOCKED_EXPIRY_AT_UTC)
        self.assertEqual(msg.expiration_time,
                         self.MOCKED_EXPIRY_AT_UTC)
        self.assertEqual(msg.label,
                         self.MOCKED_LABEL)
        self.assertEqual(msg.locked_until,
                         self.MOCKED_LOCKED_UNTIL)
        self.assertEqual(msg.lock_token,
                         self.MOCKED_LOCK_TOKEN)
        self.assertEqual(msg.message_id,
                         self.MOCKED_MESSAGE_ID)
        self.assertEqual(msg.partition_key,
                         self.MOCKED_PARTITION_KEY)
        self.assertEqual(msg.reply_to,
                         self.MOCKED_REPLY_TO)
        self.assertEqual(msg.reply_to_session_id,
                         self.MOCKED_REPLY_TO_SESSION_ID)
        self.assertEqual(msg.scheduled_enqueue_time,
                         self.MOCKED_SCHEDULED_ENQUEUE_TIME_UTC)
        self.assertEqual(msg.scheduled_enqueue_time_utc,
                         self.MOCKED_SCHEDULED_ENQUEUE_TIME_UTC)
        self.assertEqual(msg.session_id,
                         self.MOCKED_SESSION_ID)
        self.assertEqual(msg.state,
                         self.MOCKED_STATE)
        self.assertEqual(msg.subject,
                         self.MOCKED_SUBJECT)
        self.assertEqual(msg.time_to_live,
                         self.MOCKED_TIME_TO_LIVE_TIMEDELTA)
        self.assertEqual(msg.to,
                         self.MOCKED_TO)
        self.assertEqual(msg.transaction_partition_key,
                         self.MOCKED_TRANSACTION_PARTITION_KEY)
        self.assertDictEqual(msg.user_properties, {
            '$AzureWebJobsParentId': self.MOCKED_AZURE_PARTNER_ID,
            'x-opt-enqueue-sequence-number': 0
        })

    def test_servicebus_metadata(self):
        # Trigger metadata should contains all the essential information
        # about this service bus message
        servicebus_msg = azf_sb.ServiceBusMessageInConverter.decode(
            data=self._generate_single_servicebus_data(),
            trigger_metadata=self._generate_single_trigger_metadata())

        # Datetime should be in iso8601 string instead of datetime object
        metadata_dict = servicebus_msg.metadata
        self.assertGreaterEqual(metadata_dict.items(), {
            'DeliveryCount': self.MOCKED_DELIVERY_COUNT,
            'LockToken': self.MOCKED_LOCK_TOKEN,
            'ExpiresAtUtc': self.MOCKED_EXPIRY_AT_UTC.isoformat(),
            'EnqueuedTimeUtc': self.MOCKED_ENQUEUE_TIME_UTC.isoformat(),
            'MessageId': self.MOCKED_MESSAGE_ID,
            'ContentType': self.MOCKED_CONTENT_TYPE,
            'SequenceNumber': self.MOCKED_SEQUENCE_NUMBER,
            'Label': self.MOCKED_LABEL,
            'sys': {
                'MethodName': 'ServiceBusSMany',
                'UtcNow': '2020-06-18T05:39:12.2860411Z',
                'RandGuid': 'bb38deae-cc75-49f2-89f5-96ec6eb857db'
            }
        }.items())

    def test_servicebus_should_not_override_metadata(self):
        # SystemProperties in metadata should propagate to class properties
        servicebus_msg = azf_sb.ServiceBusMessageInConverter.decode(
            data=self._generate_single_servicebus_data(),
            trigger_metadata=self._generate_single_trigger_metadata())

        # The content_type trigger field should be set
        self.assertEqual(servicebus_msg.content_type, 'application/json')

        # The metadata field should also be set
        self.assertEqual(servicebus_msg.metadata['ContentType'],
                         'application/json')

        # Now we change the metadata field
        # The trigger property should still remain the same
        servicebus_msg.metadata['ContentType'] = 'text/plain'
        self.assertEqual(servicebus_msg.content_type, 'application/json')

    def test_multiple_servicebus_trigger(self):
        # When cardinality is turned on to 'many', metadata should contain
        # information for all messages
        servicebus_msgs = azf_sb.ServiceBusMessageInConverter.decode(
            data=self._generate_multiple_service_bus_data(),
            trigger_metadata=self._generate_multiple_trigger_metadata()
        )

        # The decoding result should contain a list of message
        self.assertEqual(len(servicebus_msgs), 3)

    def test_multiple_servicebus_trigger_non_existing_properties(self):
        servicebus_msgs = azf_sb.ServiceBusMessageInConverter.decode(
            data=self._generate_multiple_service_bus_data(),
            trigger_metadata={
                'MessageIdArray': meta.Datum(type='collection_string',
                                             value=CollectionString([
                                                 self.MOCKED_MESSAGE_ID,
                                                 self.MOCKED_MESSAGE_ID,
                                                 self.MOCKED_MESSAGE_ID
                                             ])),
                'UserPropertiesArray': meta.Datum(type='json',
                                                  value='''[{ "UserId": 1 },
                                                            { "UserId": 2 },
                                                            { "UserId": 3 }]
                                                        ''')
            }
        )

        # Non existing properties should return None
        self.assertIsNone(servicebus_msgs[0].content_type)
        self.assertIsNone(servicebus_msgs[1].content_type)
        self.assertIsNone(servicebus_msgs[2].content_type)

        # Message Id should always be available
        self.assertEqual(servicebus_msgs[0].message_id, self.MOCKED_MESSAGE_ID)
        self.assertEqual(servicebus_msgs[1].message_id, self.MOCKED_MESSAGE_ID)
        self.assertEqual(servicebus_msgs[2].message_id, self.MOCKED_MESSAGE_ID)

        # User properties should always be available
        self.assertEqual(servicebus_msgs[0].user_properties['UserId'], 1)
        self.assertEqual(servicebus_msgs[1].user_properties['UserId'], 2)
        self.assertEqual(servicebus_msgs[2].user_properties['UserId'], 3)

    def test_multiple_servicebus_trigger_properties(self):
        # When cardinality is turned on to 'many', metadata should contain
        # information for all messages
        servicebus_msgs = azf_sb.ServiceBusMessageInConverter.decode(
            data=self._generate_multiple_service_bus_data(),
            trigger_metadata=self._generate_multiple_trigger_metadata()
        )

        expected_bodies: List[str] = [
            json.dumps({"lucky_number": 23}),
            json.dumps({"lucky_number": 34}),
            json.dumps({"lucky_number": 45}),
        ]

        expected_message_ids: List[int] = [
            self.MOCKED_MESSAGE_ID_A,
            self.MOCKED_MESSAGE_ID_B,
            self.MOCKED_MESSAGE_ID_C
        ]

        for i in range(len(servicebus_msgs)):
            msg = servicebus_msgs[i]
            body_data = msg.get_body().decode('utf-8')
            self.assertEqual(body_data, expected_bodies[i])
            self.assertDictEqual(msg.application_properties,
                                 {"application": "value"})
            self.assertEqual(msg.content_type,
                             self.MOCKED_CONTENT_TYPE)
            self.assertEqual(msg.correlation_id,
                             self.MOCKED_CORROLATION_ID)
            self.assertEqual(msg.dead_letter_error_description,
                             self.MOCKED_DEADLETTER_ERROR_DESCRIPTION)
            self.assertEqual(msg.dead_letter_reason,
                             self.MOCKED_DEADLETTER_REASON)
            self.assertEqual(msg.dead_letter_source,
                             self.MOCKED_DEADLETTER_SOURCE)
            self.assertEqual(msg.enqueued_sequence_number,
                             self.MOCKED_ENQUEUED_SEQUENCE_NUMBER)
            self.assertEqual(msg.enqueued_time_utc,
                             self.MOCKED_ENQUEUE_TIME_UTC)
            self.assertEqual(msg.expires_at_utc,
                             self.MOCKED_EXPIRY_AT_UTC)
            self.assertEqual(msg.expiration_time,
                             self.MOCKED_EXPIRY_AT_UTC)
            self.assertEqual(msg.label,
                             self.MOCKED_LABEL)
            self.assertEqual(msg.locked_until,
                             self.MOCKED_LOCKED_UNTIL)
            self.assertEqual(msg.lock_token,
                             self.MOCKED_LOCK_TOKEN)
            self.assertEqual(msg.message_id,
                             expected_message_ids[i])
            self.assertEqual(msg.partition_key,
                             self.MOCKED_PARTITION_KEY)
            self.assertEqual(msg.reply_to,
                             self.MOCKED_REPLY_TO)
            self.assertEqual(msg.reply_to_session_id,
                             self.MOCKED_REPLY_TO_SESSION_ID)
            self.assertEqual(msg.scheduled_enqueue_time,
                             self.MOCKED_SCHEDULED_ENQUEUE_TIME_UTC)
            self.assertEqual(msg.scheduled_enqueue_time_utc,
                             self.MOCKED_SCHEDULED_ENQUEUE_TIME_UTC)
            self.assertEqual(msg.session_id,
                             self.MOCKED_SESSION_ID)
            self.assertEqual(msg.state,
                             self.MOCKED_STATE)
            self.assertEqual(msg.subject,
                             self.MOCKED_SUBJECT)
            self.assertEqual(msg.time_to_live,
                             self.MOCKED_TIME_TO_LIVE_TIMEDELTA)
            self.assertEqual(msg.to,
                             self.MOCKED_TO)
            self.assertEqual(msg.transaction_partition_key,
                             self.MOCKED_TRANSACTION_PARTITION_KEY)
            self.assertDictEqual(msg.user_properties, {
                '$AzureWebJobsParentId': self.MOCKED_AZURE_PARTNER_ID,
                'x-opt-enqueue-sequence-number': 0
            })

    def test_servicebus_message_out_converter_encode_str(self):

        data = "dummy_string"

        result = azf_sb.ServiceBusMessageOutConverter.encode(
            obj=data, expected_type=None)

        self.assertEqual(result.type, "string")
        self.assertEqual(result.python_value, data)

    def test_servicebus_message_out_converter_encode_bytes(self):

        data = b"dummy_bytes"

        result = azf_sb.ServiceBusMessageOutConverter.encode(
            obj=data, expected_type=None)

        self.assertEqual(result.type, "bytes")
        self.assertEqual(result.python_value, data)

    def _generate_single_servicebus_data(self) -> meta.Datum:
        return meta.Datum(value=json.dumps({
            'lucky_number': 23
        }), type='json')

    def _generate_multiple_service_bus_data(self) -> meta.Datum:
        return meta.Datum(value=json.dumps([
            {'lucky_number': 23},
            {'lucky_number': 34},
            {'lucky_number': 45}
        ]), type='json')

    def _generate_single_trigger_metadata(self) -> Dict[str, meta.Datum]:
        """Generate a single ServiceBus message following
        https://docs.microsoft.com/en-us/azure/service-bus-messaging/
        service-bus-messages-payloads
        """

        mocked_metadata: Dict[str, meta.Datum] = {
            'ContentType': meta.Datum(
                self.MOCKED_CONTENT_TYPE, 'string'
            ),
            'CorrelationId': meta.Datum(
                self.MOCKED_CORROLATION_ID, 'string'
            ),
            'DeadLetterErrorDescription': meta.Datum(
                self.MOCKED_DEADLETTER_ERROR_DESCRIPTION, 'string'
            ),
            'DeadLetterReason': meta.Datum(
                self.MOCKED_DEADLETTER_REASON, 'string'
            ),
            'DeadLetterSource': meta.Datum(
                self.MOCKED_DEADLETTER_SOURCE, 'string'
            ),
            'DeliveryCount': meta.Datum(
                self.MOCKED_DELIVERY_COUNT, 'int'
            ),
            'EnqueuedSequenceNumber': meta.Datum(
                self.MOCKED_ENQUEUED_SEQUENCE_NUMBER, 'int'
            ),
            'EnqueuedTimeUtc': meta.Datum(
                self.MOCKED_ENQUEUE_TIME_UTC.isoformat(), 'string'
            ),
            'ExpiresAtUtc': meta.Datum(
                self.MOCKED_EXPIRY_AT_UTC.isoformat(), 'string'
            ),
            # 'ForcePersistence' not exposed yet, requires gRPC boolean passing
            'Label': meta.Datum(
                self.MOCKED_LABEL, 'string'
            ),
            'LockedUntil': meta.Datum(
                self.MOCKED_LOCKED_UNTIL.isoformat(), 'string'
            ),
            'LockToken': meta.Datum(
                self.MOCKED_LOCK_TOKEN, 'string'
            ),
            'MessageId': meta.Datum(
                self.MOCKED_MESSAGE_ID, 'string'
            ),
            'PartitionKey': meta.Datum(
                self.MOCKED_PARTITION_KEY, 'string'
            ),
            'ReplyTo': meta.Datum(
                self.MOCKED_REPLY_TO, 'string'
            ),
            'ReplyToSessionId': meta.Datum(
                self.MOCKED_REPLY_TO_SESSION_ID, 'string'
            ),
            'ScheduledEnqueueTimeUtc': meta.Datum(
                self.MOCKED_SCHEDULED_ENQUEUE_TIME_UTC.isoformat(), 'string'
            ),
            'SequenceNumber': meta.Datum(
                self.MOCKED_SEQUENCE_NUMBER, 'int'
            ),
            'SessionId': meta.Datum(
                self.MOCKED_SESSION_ID, 'string'
            ),
            'State': meta.Datum(
                self.MOCKED_STATE, 'int'
            ),
            'Subject': meta.Datum(
                self.MOCKED_SUBJECT, 'string'
            ),
            'TimeToLive': meta.Datum(
                self.MOCKED_TIME_TO_LIVE, 'string'
            ),
            'To': meta.Datum(
                self.MOCKED_TO, 'string'
            ),
            'TransactionPartitionKey': meta.Datum(
                self.MOCKED_TRANSACTION_PARTITION_KEY, 'string'
            )
        }
        mocked_metadata['MessageReceiver'] = meta.Datum(type='json', value='''
        {
            "RegisteredPlugins": [],
            "ReceiveMode": 0,
            "PrefetchCount": 0,
            "LastPeekedSequenceNumber": 0,
            "Path": "testqueue",
            "OperationTimeout": "00:01:00",
            "ServiceBusConnection": {
                "Endpoint": "sb://python-worker-36-sbns.servicebus.win.net",
                "OperationTimeout": "00:01:00",
                "RetryPolicy": {
                    "MinimalBackoff": "00:00:00",
                    "MaximumBackoff": "00:00:30",
                    "DeltaBackoff": "00:00:03",
                    "MaxRetryCount": 5,
                    "IsServerBusy": false,
                    "ServerBusyExceptionMessage": null
                },
                "TransportType": 0,
                "TokenProvider": {}
            },
            "IsClosedOrClosing": false,
            "ClientId": "MessageReceiver1testqueue",
            "RetryPolicy": {
                "MinimalBackoff": "00:00:00",
                "MaximumBackoff": "00:00:30",
                "DeltaBackoff": "00:00:03",
                "MaxRetryCount": 5,
                "IsServerBusy": false,
                "ServerBusyExceptionMessage": null
            }
        }''')
        mocked_metadata['ApplicationProperties'] = meta.Datum(type='json', value='''
        {
            "application": "value"
        }
        ''')
        mocked_metadata['UserProperties'] = meta.Datum(type='json', value='''
        {
            "$AzureWebJobsParentId": "6ceef68b-0794-45dd-bb2e-630748515552",
            "x-opt-enqueue-sequence-number": 0
        }''')
        mocked_metadata['sys'] = meta.Datum(type='json', value='''
        {
            "MethodName": "ServiceBusSMany",
            "UtcNow": "2020-06-18T05:39:12.2860411Z",
            "RandGuid": "bb38deae-cc75-49f2-89f5-96ec6eb857db"
        }
        ''')
        return mocked_metadata

    def _generate_multiple_trigger_metadata(self) -> Dict[str, meta.Datum]:
        """Generate a metadatum containing 3 service bus messages which can be
        distingushed by enqueued_sequence_number
        """
        sb_a = self._generate_single_trigger_metadata()
        sb_b = self._generate_single_trigger_metadata()
        sb_c = self._generate_single_trigger_metadata()

        sb_a['MessageId'] = meta.Datum(self.MOCKED_MESSAGE_ID_A, 'string')
        sb_b['MessageId'] = meta.Datum(self.MOCKED_MESSAGE_ID_B, 'string')
        sb_c['MessageId'] = meta.Datum(self.MOCKED_MESSAGE_ID_C, 'string')

        combine_from = lambda key, et: self._zip(key, et, sb_a, sb_b, sb_c)

        mocked_metadata = {
            'ApplicationPropertiesArray': combine_from(
                'ApplicationProperties', 'json'
            ),
            'ContentTypeArray': combine_from(
                'ContentType', 'collection_string'
            ),
            'CorrelationIdArray': combine_from(
                'CorrelationId', 'collection_string'
            ),
            'DeadLetterErrorDescriptionArray': combine_from(
                'DeadLetterErrorDescription', 'collection_string'
            ),
            'DeadLetterReasonArray': combine_from(
                'DeadLetterReason', 'collection_string'
            ),
            'DeadLetterSourceArray': combine_from(
                'DeadLetterSource', 'collection_string'
            ),
            'EnqueuedSequenceNumberArray': combine_from(
                'EnqueuedSequenceNumber', 'collection_sint64'
            ),
            'EnqueuedTimeUtcArray': combine_from(
                'EnqueuedTimeUtc', 'json'
            ),
            'ExpiresAtUtcArray': combine_from(
                'ExpiresAtUtc', 'json'
            ),
            'LabelArray': combine_from(
                'Label', 'collection_string'
            ),
            'LockedUntilArray': combine_from(
                'LockedUntil', 'json'
            ),
            'LockTokenArray': combine_from(
                'LockToken', 'collection_string'
            ),
            'MessageIdArray': combine_from(
                'MessageId', 'collection_string'
            ),
            'PartitionKeyArray': combine_from(
                'PartitionKey', 'collection_string'
            ),
            'ReplyToArray': combine_from(
                'ReplyTo', 'collection_string'
            ),
            'ReplyToSessionIdArray': combine_from(
                'ReplyToSessionId', 'collection_string'
            ),
            'ScheduledEnqueueTimeUtcArray': combine_from(
                'ScheduledEnqueueTimeUtc', 'collection_string'
            ),
            'SessionIdArray': combine_from(
                'SessionId', 'collection_string'
            ),
            'SequenceNumberArray': combine_from(
                'SequenceNumber', 'collection_sint64'
            ),
            'StateArray': combine_from(
                'State', 'collection_sint64'
            ),
            'SubjectArray': combine_from(
                'Subject', 'collection_string'
            ),
            'TimeToLiveArray': combine_from(
                'TimeToLive', 'collection_string'
            ),
            'ToArray': combine_from(
                'To', 'collection_string'
            ),
            'TransactionPartitionKeyArray': combine_from(
                'TransactionPartitionKey', 'collection_string'
            ),
            'UserPropertiesArray': combine_from(
                'UserProperties', 'json'
            )
        }

        return mocked_metadata

    def _zip(self, key: str, expected_type: str,
             *args: List[Dict[str, meta.Datum]]) -> meta.Datum:
        """Combining multiple metadata into one:
        string -> collection_string
        bytes -> collection_bytes
        int -> collection_sint64
        sint64 -> collection_sint64
        json -> json (with array in it)
        """
        convertible = {
            'collection_string': CollectionString,
            'collection_bytes': CollectionBytes,
            'collection_sint64': CollectionSint64
        }

        datum_type = args[0][key].type
        if expected_type in convertible.keys():
            return meta.Datum(
                value=convertible[expected_type]([d[key].value for d in args]),
                type=expected_type
            )
        elif expected_type == 'json':
            if datum_type == 'json':
                value = json.dumps([json.loads(d[key].value) for d in args])
            else:
                value = json.dumps([d[key].value for d in args])
            return meta.Datum(
                value=value,
                type='json'
            )
        else:
            raise NotImplementedError(f'Unknown convertion {key}: '
                                      f'{datum_type} -> {expected_type}')