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Sns  >  Structures  >  PublishBatchRequestEntry

PublishBatchRequestEntry

Structure Class

PublishBatchRequestEntry dataclass

Contains the details of a single Amazon SNS message along with an Id that identifies a message within the batch.

Attributes

id instance-attribute 
id: str

An identifier for the message in this batch.

Note

The Ids of a batch request must be unique within a request.

This identifier can have up to 80 characters. The following characters are accepted: alphanumeric characters, hyphens(-), and underscores (_).

message instance-attribute 
message: str

The body of the message.

message_attributes class-attribute instance-attribute 
message_attributes: dict[str, MessageAttributeValue] | None = None

Each message attribute consists of a Name, Type, and Value. For more information, see Amazon SNS message attributes in the Amazon SNS Developer Guide.

message_deduplication_id class-attribute instance-attribute 
message_deduplication_id: str | None = None

This parameter applies only to FIFO (first-in-first-out) topics.

  • This parameter applies only to FIFO (first-in-first-out) topics. The MessageDeduplicationId can contain up to 128 alphanumeric characters (a-z, A-Z, 0-9) and punctuation (!"#$%&'()*+,-./:;<=>?@[]^_`{|}~).

  • Every message must have a unique MessageDeduplicationId, which is a token used for deduplication of sent messages within the 5 minute minimum deduplication interval.

  • The scope of deduplication depends on the FifoThroughputScope attribute, when set to Topic the message deduplication scope is across the entire topic, when set to MessageGroup the message deduplication scope is within each individual message group.

  • If a message with a particular MessageDeduplicationId is sent successfully, subsequent messages within the deduplication scope and interval, with the same MessageDeduplicationId, are accepted successfully but aren't delivered.

  • Every message must have a unique MessageDeduplicationId.

  • You may provide a MessageDeduplicationId explicitly.

  • If you aren't able to provide a MessageDeduplicationId and you enable ContentBasedDeduplication for your topic, Amazon SNS uses a SHA-256 hash to generate the MessageDeduplicationId using the body of the message (but not the attributes of the message).

  • If you don't provide a MessageDeduplicationId and the topic doesn't have ContentBasedDeduplication set, the action fails with an error.

  • If the topic has a ContentBasedDeduplication set, your MessageDeduplicationId overrides the generated one.

  • When ContentBasedDeduplication is in effect, messages with identical content sent within the deduplication scope and interval are treated as duplicates and only one copy of the message is delivered.

  • If you send one message with ContentBasedDeduplication enabled, and then another message with a MessageDeduplicationId that is the same as the one generated for the first MessageDeduplicationId, the two messages are treated as duplicates, within the deduplication scope and interval, and only one copy of the message is delivered.

Note

The MessageDeduplicationId is available to the consumer of the message (this can be useful for troubleshooting delivery issues).

If a message is sent successfully but the acknowledgement is lost and the message is resent with the same MessageDeduplicationId after the deduplication interval, Amazon SNS can't detect duplicate messages.

Amazon SNS continues to keep track of the message deduplication ID even after the message is received and deleted.

message_group_id class-attribute instance-attribute 
message_group_id: str | None = None

FIFO topics: The tag that specifies that a message belongs to a specific message group. Messages that belong to the same message group are processed in a FIFO manner (however, messages in different message groups might be processed out of order). To interleave multiple ordered streams within a single topic, use MessageGroupId values (for example, session data for multiple users). In this scenario, multiple consumers can process the topic, but the session data of each user is processed in a FIFO fashion. You must associate a non-empty MessageGroupId with a message. If you do not provide a MessageGroupId, the action fails.

Standard topics: The MessageGroupId is optional and is forwarded only to Amazon SQS standard subscriptions to activate fair queues. The MessageGroupId is not used for, or sent to, any other endpoint types.

The length of MessageGroupId is 128 characters.

MessageGroupId can contain alphanumeric characters (a-z, A-Z, 0-9) and punctuation (!"#$%&'()*+,-./:;<=>?@[]^_`{|}~).

message_structure class-attribute instance-attribute 
message_structure: str | None = None

Set MessageStructure to json if you want to send a different message for each protocol. For example, using one publish action, you can send a short message to your SMS subscribers and a longer message to your email subscribers. If you set MessageStructure to json, the value of the Message parameter must:

  • be a syntactically valid JSON object; and

  • contain at least a top-level JSON key of "default" with a value that is a string.

You can define other top-level keys that define the message you want to send to a specific transport protocol (for example, http).

subject class-attribute instance-attribute 
subject: str | None = None

The subject of the batch message.