Source code for azure.eventhub._common

# --------------------------------------------------------------------------------------------
# Copyright (c) Microsoft Corporation. All rights reserved.
# Licensed under the MIT License. See License.txt in the project root for license information.
# --------------------------------------------------------------------------------------------
from __future__ import unicode_literals

import json
import logging
from typing import (
    Union,
    Dict,
    Any,
    AnyStr,
    Iterable,
    Optional,
    List,
    TYPE_CHECKING,
    cast,
)

import six

from uamqp import BatchMessage, Message, constants

from ._utils import set_message_partition_key, trace_message, utc_from_timestamp
from ._constants import (
    PROP_SEQ_NUMBER,
    PROP_OFFSET,
    PROP_PARTITION_KEY,
    PROP_PARTITION_KEY_AMQP_SYMBOL,
    PROP_TIMESTAMP,
    PROP_ABSOLUTE_EXPIRY_TIME,
    PROP_CONTENT_ENCODING,
    PROP_CONTENT_TYPE,
    PROP_CORRELATION_ID,
    PROP_GROUP_ID,
    PROP_GROUP_SEQUENCE,
    PROP_MESSAGE_ID,
    PROP_REPLY_TO,
    PROP_REPLY_TO_GROUP_ID,
    PROP_SUBJECT,
    PROP_TO,
    PROP_USER_ID,
    PROP_CREATION_TIME,
)

if TYPE_CHECKING:
    import datetime

_LOGGER = logging.getLogger(__name__)

# event_data.encoded_size < 255, batch encode overhead is 5, >=256, overhead is 8 each
_BATCH_MESSAGE_OVERHEAD_COST = [5, 8]

_SYS_PROP_KEYS_TO_MSG_PROPERTIES = (
    (PROP_MESSAGE_ID, "message_id"),
    (PROP_USER_ID, "user_id"),
    (PROP_TO, "to"),
    (PROP_SUBJECT, "subject"),
    (PROP_REPLY_TO, "reply_to"),
    (PROP_CORRELATION_ID, "correlation_id"),
    (PROP_CONTENT_TYPE, "content_type"),
    (PROP_CONTENT_ENCODING, "content_encoding"),
    (PROP_ABSOLUTE_EXPIRY_TIME, "absolute_expiry_time"),
    (PROP_CREATION_TIME, "creation_time"),
    (PROP_GROUP_ID, "group_id"),
    (PROP_GROUP_SEQUENCE, "group_sequence"),
    (PROP_REPLY_TO_GROUP_ID, "reply_to_group_id"),
)


[docs]class EventData(object): """The EventData class is a container for event content. :param body: The data to send in a single message. body can be type of str or bytes. :type body: str or bytes .. admonition:: Example: .. literalinclude:: ../samples/sync_samples/sample_code_eventhub.py :start-after: [START create_event_data] :end-before: [END create_event_data] :language: python :dedent: 4 :caption: Create instances of EventData """ def __init__(self, body=None): # type: (Union[str, bytes, List[AnyStr]]) -> None self._last_enqueued_event_properties = {} # type: Dict[str, Any] self._sys_properties = None # type: Optional[Dict[bytes, Any]] if body and isinstance(body, list): self.message = Message(body[0]) for more in body[1:]: self.message._body.append(more) # pylint: disable=protected-access elif body is None: raise ValueError("EventData cannot be None.") else: self.message = Message(body) self.message.annotations = {} self.message.application_properties = {} def __repr__(self): # type: () -> str # pylint: disable=bare-except try: body_str = self.body_as_str() except: body_str = "<read-error>" event_repr = "body='{}'".format(body_str) try: event_repr += ", properties={}".format(self.properties) except: event_repr += ", properties=<read-error>" try: event_repr += ", offset={}".format(self.offset) except: event_repr += ", offset=<read-error>" try: event_repr += ", sequence_number={}".format(self.sequence_number) except: event_repr += ", sequence_number=<read-error>" try: event_repr += ", partition_key={!r}".format(self.partition_key) except: event_repr += ", partition_key=<read-error>" try: event_repr += ", enqueued_time={!r}".format(self.enqueued_time) except: event_repr += ", enqueued_time=<read-error>" return "EventData({})".format(event_repr) def __str__(self): # type: () -> str try: body_str = self.body_as_str() except: # pylint: disable=bare-except body_str = "<read-error>" event_str = "{{ body: '{}'".format(body_str) try: event_str += ", properties: {}".format(self.properties) if self.offset: event_str += ", offset: {}".format(self.offset) if self.sequence_number: event_str += ", sequence_number: {}".format(self.sequence_number) if self.partition_key: event_str += ", partition_key={!r}".format(self.partition_key) if self.enqueued_time: event_str += ", enqueued_time={!r}".format(self.enqueued_time) except: # pylint: disable=bare-except pass event_str += " }" return event_str @classmethod def _from_message(cls, message): # type: (Message) -> EventData """Internal use only. Creates an EventData object from a raw uamqp message. :param ~uamqp.Message message: A received uamqp message. :rtype: ~azure.eventhub.EventData """ event_data = cls(body="") event_data.message = message return event_data def _encode_message(self): # type: () -> bytes return self.message.encode_message() @property def sequence_number(self): # type: () -> Optional[int] """The sequence number of the event. :rtype: int """ return self.message.annotations.get(PROP_SEQ_NUMBER, None) @property def offset(self): # type: () -> Optional[str] """The offset of the event. :rtype: str """ try: return self.message.annotations[PROP_OFFSET].decode("UTF-8") except (KeyError, AttributeError): return None @property def enqueued_time(self): # type: () -> Optional[datetime.datetime] """The enqueued timestamp of the event. :rtype: datetime.datetime """ timestamp = self.message.annotations.get(PROP_TIMESTAMP, None) if timestamp: return utc_from_timestamp(float(timestamp) / 1000) return None @property def partition_key(self): # type: () -> Optional[bytes] """The partition key of the event. :rtype: bytes """ try: return self.message.annotations[PROP_PARTITION_KEY_AMQP_SYMBOL] except KeyError: return self.message.annotations.get(PROP_PARTITION_KEY, None) @property def properties(self): # type: () -> Dict[Union[str, bytes], Any] """Application-defined properties on the event. :rtype: dict """ return self.message.application_properties @properties.setter def properties(self, value): # type: (Dict[Union[str, bytes], Any]) -> None """Application-defined properties on the event. :param dict value: The application properties for the EventData. """ properties = None if value is None else dict(value) self.message.application_properties = properties @property def system_properties(self): # type: () -> Dict[bytes, Any] """Metadata set by the Event Hubs Service associated with the event. An EventData could have some or all of the following meta data depending on the source of the event data. - b"x-opt-sequence-number" (int) - b"x-opt-offset" (bytes) - b"x-opt-partition-key" (bytes) - b"x-opt-enqueued-time" (int) - b"message-id" (bytes) - b"user-id" (bytes) - b"to" (bytes) - b"subject" (bytes) - b"reply-to" (bytes) - b"correlation-id" (bytes) - b"content-type" (bytes) - b"content-encoding" (bytes) - b"absolute-expiry-time" (int) - b"creation-time" (int) - b"group-id" (bytes) - b"group-sequence" (bytes) - b"reply-to-group-id" (bytes) :rtype: dict """ if self._sys_properties is None: self._sys_properties = {} if self.message.properties: for key, prop_name in _SYS_PROP_KEYS_TO_MSG_PROPERTIES: value = getattr(self.message.properties, prop_name, None) if value: self._sys_properties[key] = value self._sys_properties.update(self.message.annotations) return self._sys_properties @property def body(self): # type: () -> Union[bytes, Iterable[bytes]] """The content of the event. :rtype: bytes or Generator[bytes] """ try: return self.message.get_data() except TypeError: raise ValueError("Event content empty.")
[docs] def body_as_str(self, encoding="UTF-8"): # type: (str) -> str """The content of the event as a string, if the data is of a compatible type. :param encoding: The encoding to use for decoding event data. Default is 'UTF-8' :rtype: str """ data = self.body try: return "".join(b.decode(encoding) for b in cast(Iterable[bytes], data)) except TypeError: return six.text_type(data) except: # pylint: disable=bare-except pass try: return cast(bytes, data).decode(encoding) except Exception as e: raise TypeError( "Message data is not compatible with string type: {}".format(e) )
[docs] def body_as_json(self, encoding="UTF-8"): # type: (str) -> Dict[str, Any] """The content of the event loaded as a JSON object, if the data is compatible. :param encoding: The encoding to use for decoding event data. Default is 'UTF-8' :rtype: dict """ data_str = self.body_as_str(encoding=encoding) try: return json.loads(data_str) except Exception as e: raise TypeError("Event data is not compatible with JSON type: {}".format(e))
[docs]class EventDataBatch(object): """A batch of events. Sending events in a batch is more performant than sending individual events. EventDataBatch helps you create the maximum allowed size batch of `EventData` to improve sending performance. Use the `add` method to add events until the maximum batch size limit in bytes has been reached - at which point a `ValueError` will be raised. Use the `send_batch` method of :class:`EventHubProducerClient<azure.eventhub.EventHubProducerClient>` or the async :class:`EventHubProducerClient<azure.eventhub.aio.EventHubProducerClient>` for sending. **Please use the create_batch method of EventHubProducerClient to create an EventDataBatch object instead of instantiating an EventDataBatch object directly.** **WARNING: Updating the value of the instance variable max_size_in_bytes on an instantiated EventDataBatch object is HIGHLY DISCOURAGED. The updated max_size_in_bytes value may conflict with the maximum size of events allowed by the Event Hubs service and result in a sending failure.** :param int max_size_in_bytes: The maximum size of bytes data that an EventDataBatch object can hold. :param str partition_id: The specific partition ID to send to. :param str partition_key: With the given partition_key, event data will be sent to a particular partition of the Event Hub decided by the service. """ def __init__(self, max_size_in_bytes=None, partition_id=None, partition_key=None): # type: (Optional[int], Optional[str], Optional[Union[str, bytes]]) -> None if partition_key and not isinstance(partition_key, (six.text_type, six.binary_type)): _LOGGER.info( "WARNING: Setting partition_key of non-string value on the events to be sent is discouraged " "as the partition_key will be ignored by the Event Hub service and events will be assigned " "to all partitions using round-robin. Furthermore, there are SDKs for consuming events which expect " "partition_key to only be string type, they might fail to parse the non-string value." ) self.max_size_in_bytes = max_size_in_bytes or constants.MAX_MESSAGE_LENGTH_BYTES self.message = BatchMessage(data=[], multi_messages=False, properties=None) self._partition_id = partition_id self._partition_key = partition_key set_message_partition_key(self.message, self._partition_key) self._size = self.message.gather()[0].get_message_encoded_size() self._count = 0 def __repr__(self): # type: () -> str batch_repr = "max_size_in_bytes={}, partition_id={}, partition_key={!r}, event_count={}".format( self.max_size_in_bytes, self._partition_id, self._partition_key, self._count ) return "EventDataBatch({})".format(batch_repr) def __len__(self): return self._count @classmethod def _from_batch(cls, batch_data, partition_key=None): # type: (Iterable[EventData], Optional[AnyStr]) -> EventDataBatch batch_data_instance = cls(partition_key=partition_key) batch_data_instance.message._body_gen = ( # pylint:disable=protected-access batch_data ) return batch_data_instance def _load_events(self, events): for event_data in events: try: self.add(event_data) except ValueError: raise ValueError("The combined size of EventData collection exceeds the Event Hub frame size limit. " "Please send a smaller collection of EventData, or use EventDataBatch, " "which is guaranteed to be under the frame size limit") @property def size_in_bytes(self): # type: () -> int """The combined size of the events in the batch, in bytes. :rtype: int """ return self._size
[docs] def add(self, event_data): # type: (EventData) -> None """Try to add an EventData to the batch. The total size of an added event is the sum of its body, properties, etc. If this added size results in the batch exceeding the maximum batch size, a `ValueError` will be raised. :param event_data: The EventData to add to the batch. :type event_data: ~azure.eventhub.EventData :rtype: None :raise: :class:`ValueError`, when exceeding the size limit. """ if self._partition_key: if ( event_data.partition_key and event_data.partition_key != self._partition_key ): raise ValueError( "The partition key of event_data does not match the partition key of this batch." ) if not event_data.partition_key: set_message_partition_key(event_data.message, self._partition_key) trace_message(event_data) event_data_size = event_data.message.get_message_encoded_size() # For a BatchMessage, if the encoded_message_size of event_data is < 256, then the overhead cost to encode that # message into the BatchMessage would be 5 bytes, if >= 256, it would be 8 bytes. size_after_add = ( self._size + event_data_size + _BATCH_MESSAGE_OVERHEAD_COST[0 if (event_data_size < 256) else 1] ) if size_after_add > self.max_size_in_bytes: raise ValueError( "EventDataBatch has reached its size limit: {}".format( self.max_size_in_bytes ) ) self.message._body_gen.append(event_data) # pylint: disable=protected-access self._size = size_after_add self._count += 1
class DictMixin(object): def __setitem__(self, key, item): # type: (Any, Any) -> None self.__dict__[key] = item def __getitem__(self, key): # type: (Any) -> Any return self.__dict__[key] def __contains__(self, key): return key in self.__dict__ def __repr__(self): # type: () -> str return str(self) def __len__(self): # type: () -> int return len(self.keys()) def __delitem__(self, key): # type: (Any) -> None self.__dict__[key] = None def __eq__(self, other): # type: (Any) -> bool """Compare objects by comparing all attributes.""" if isinstance(other, self.__class__): return self.__dict__ == other.__dict__ return False def __ne__(self, other): # type: (Any) -> bool """Compare objects by comparing all attributes.""" return not self.__eq__(other) def __str__(self): # type: () -> str return str({k: v for k, v in self.__dict__.items() if not k.startswith("_")}) def has_key(self, k): # type: (Any) -> bool return k in self.__dict__ def update(self, *args, **kwargs): # type: (Any, Any) -> None return self.__dict__.update(*args, **kwargs) def keys(self): # type: () -> list return [k for k in self.__dict__ if not k.startswith("_")] def values(self): # type: () -> list return [v for k, v in self.__dict__.items() if not k.startswith("_")] def items(self): # type: () -> list return [(k, v) for k, v in self.__dict__.items() if not k.startswith("_")] def get(self, key, default=None): # type: (Any, Optional[Any]) -> Any if key in self.__dict__: return self.__dict__[key] return default