Message(message: types.PubsubMessage._meta._pb, ack_id: str, delivery_attempt: int, request_queue: queue.Queue, exactly_once_delivery_enabled_func: Callable[[], bool] = <function Message.<lambda>>)A representation of a single Pub/Sub message.
The common way to interact with
.pubsub_v1.subscriber.message.Message objects is to receive
them in callbacks on subscriptions; most users should never have a need
to instantiate them by hand. (The exception to this is if you are
implementing a custom subclass to
.pubsub_v1.subscriber._consumer.Consumer.)
Attributes | |
|---|---|
| Name | Description |
message_id |
str
The message ID. In general, you should not need to use this directly. |
data |
bytes
The data in the message. Note that this will be a bytes,
not a text string.
|
attributes |
MutableMapping[str, str]
The attributes sent along with the message. See attributes for more
information on this type.
|
publish_time |
google.protobuf.timestamp_pb2.Timestamp
The time that this message was originally published. |
Properties
ack_id
the ID used to ack the message.
attributes
Return the attributes of the underlying Pub/Sub Message.
| Returns | |
|---|---|
| Type | Description |
containers.ScalarMap | The message's attributes. This is a dict-like object provided by google.protobuf. |
data
Return the data for the underlying Pub/Sub Message.
| Returns | |
|---|---|
| Type | Description |
bytes | The message data. This is always a bytestring; if you want a text string, call bytes.decode. |
delivery_attempt
The delivery attempt counter is 1 + (the sum of number of NACKs and number of ack_deadline exceeds) for this message. It is set to None if a DeadLetterPolicy is not set on the subscription.
A NACK is any call to ModifyAckDeadline with a 0 deadline. An ack_deadline exceeds event is whenever a message is not acknowledged within ack_deadline. Note that ack_deadline is initially Subscription.ackDeadlineSeconds, but may get extended automatically by the client library.
The first delivery of a given message will have this value as 1. The value is calculated at best effort and is approximate.
| Returns | |
|---|---|
| Type | Description |
Optional[int] | The delivery attempt counter or None. |
ordering_key
The ordering key used to publish the message.
publish_time
Return the time that the message was originally published.
| Returns | |
|---|---|
| Type | Description |
datetime.datetime | The date and time that the message was published. |
size
Return the size of the underlying message, in bytes.
Methods
Message
Message(message: types.PubsubMessage._meta._pb, ack_id: str, delivery_attempt: int, request_queue: queue.Queue, exactly_once_delivery_enabled_func: Callable[[], bool] = <function Message.<lambda>>)Construct the Message.
| Parameters | |
|---|---|
| Name | Description |
ack_id |
str
The ack_id received from Pub/Sub. |
delivery_attempt |
int
The delivery attempt counter received from Pub/Sub if a DeadLetterPolicy is set on the subscription, and zero otherwise. |
exactly_once_delivery_enabled_func |
Callable[[], bool]
A Callable that returns whether exactly-once delivery is currently-enabled. Defaults to a lambda that always returns False. |
message |
types.PubsubMessage._meta._pb
The message received from Pub/Sub. For performance reasons it should be the raw protobuf message normally wrapped by |
request_queue |
queue.Queue
A queue provided by the policy that can accept requests; the policy is responsible for handling those requests. |
ack
ack()Acknowledge the given message.
Acknowledging a message in Pub/Sub means that you are done with it, and it will not be delivered to this subscription again. You should avoid acknowledging messages until you have finished processing them, so that in the event of a failure, you receive the message again.
ack_with_response
ack_with_response()Acknowledge the given message.
Acknowledging a message in Pub/Sub means that you are done with it, and it will not be delivered to this subscription again. You should avoid acknowledging messages until you have finished processing them, so that in the event of a failure, you receive the message again.
If exactly-once delivery is NOT enabled on the subscription, the future returns immediately with an AcknowledgeStatus.SUCCESS. Since acks in Cloud Pub/Sub are best effort when exactly-once delivery is disabled, the message may be re-delivered. Because re-deliveries are possible, you should ensure that your processing code is idempotent, as you may receive any given message more than once.
If exactly-once delivery is enabled on the subscription, the future returned by this method tracks the state of acknowledgement operation. If the future completes successfully, the message is guaranteed NOT to be re-delivered. Otherwise, the future will contain an exception with more details about the failure and the message may be re-delivered.
Exactly once delivery is a preview feature. For more details, see https://cloud.google.com/pubsub/docs/exactly-once-delivery."
| Returns | |
|---|---|
| Type | Description |
futures.Future | A Future instance that conforms to Python Standard library's concurrent.futures.Future interface (but not an instance of that class). Call result() to get the result of the operation; upon success, a pubsub_v1.subscriber.exceptions.AcknowledgeStatus.SUCCESS will be returned and upon an error, an pubsub_v1.subscriber.exceptions.AcknowledgeError exception will be thrown. |
drop
drop()Release the message from lease management.
This informs the policy to no longer hold on to the lease for this message. Pub/Sub will re-deliver the message if it is not acknowledged before the existing lease expires.
modify_ack_deadline
modify_ack_deadline(seconds: int)Resets the deadline for acknowledgement.
New deadline will be the given value of seconds from now.
The default implementation handles automatically modacking received messages for you;
you should not need to manually deal with setting ack deadlines. The exception case is
if you are implementing your own custom subclass of
.pubsub_v1.subcriber._consumer.Consumer.
| Parameter | |
|---|---|
| Name | Description |
seconds |
int
The number of seconds to set the lease deadline to. This should be between 0 and 600. Due to network latency, values below 10 are advised against. |
modify_ack_deadline_with_response
modify_ack_deadline_with_response(seconds: int)Resets the deadline for acknowledgement and returns the response status via a future.
New deadline will be the given value of seconds from now.
The default implementation handles automatically modacking received messages for you;
you should not need to manually deal with setting ack deadlines. The exception case is
if you are implementing your own custom subclass of
.pubsub_v1.subcriber._consumer.Consumer.
If exactly-once delivery is NOT enabled on the subscription, the future returns immediately with an AcknowledgeStatus.SUCCESS. Since modify-ack-deadline operations in Cloud Pub/Sub are best effort when exactly-once delivery is disabled, the message may be re-delivered within the set deadline.
If exactly-once delivery is enabled on the subscription, the future returned by this method tracks the state of the modify-ack-deadline operation. If the future completes successfully, the message is guaranteed NOT to be re-delivered within the new deadline. Otherwise, the future will contain an exception with more details about the failure and the message will be redelivered according to its currently-set ack deadline.
Exactly once delivery is a preview feature. For more details, see https://cloud.google.com/pubsub/docs/exactly-once-delivery."
| Parameter | |
|---|---|
| Name | Description |
seconds |
int
The number of seconds to set the lease deadline to. This should be between 0 and 600. Due to network latency, values below 10 are advised against. |
| Returns | |
|---|---|
| Type | Description |
futures.Future | A Future instance that conforms to Python Standard library's concurrent.futures.Future interface (but not an instance of that class). Call result() to get the result of the operation; upon success, a pubsub_v1.subscriber.exceptions.AcknowledgeStatus.SUCCESS will be returned and upon an error, an pubsub_v1.subscriber.exceptions.AcknowledgeError exception will be thrown. |
nack
nack()Decline to acknowledge the given message.
This will cause the message to be re-delivered to subscribers. Re-deliveries may take place immediately or after a delay, and may arrive at this subscriber or another.
nack_with_response
nack_with_response()Decline to acknowledge the given message, returning the response status via a future.
This will cause the message to be re-delivered to subscribers. Re-deliveries may take place immediately or after a delay, and may arrive at this subscriber or another.
If exactly-once delivery is NOT enabled on the subscription, the future returns immediately with an AcknowledgeStatus.SUCCESS.
If exactly-once delivery is enabled on the subscription, the future returned by this method tracks the state of the nack operation. If the future completes successfully, the future's result will be an AcknowledgeStatus.SUCCESS. Otherwise, the future will contain an exception with more details about the failure.
Exactly once delivery is a preview feature. For more details, see https://cloud.google.com/pubsub/docs/exactly-once-delivery."
| Returns | |
|---|---|
| Type | Description |
futures.Future | A Future instance that conforms to Python Standard library's concurrent.futures.Future interface (but not an instance of that class). Call result() to get the result of the operation; upon success, a pubsub_v1.subscriber.exceptions.AcknowledgeStatus.SUCCESS will be returned and upon an error, an pubsub_v1.subscriber.exceptions.AcknowledgeError exception will be thrown. |