2021/11/17 - Amazon Simple Notification Service - 1 new api methods
Changes Amazon SNS introduces the PublishBatch API, which enables customers to publish up to 10 messages per API request. The new API is valid for Standard and FIFO topics.
Publishes up to ten messages to the specified topic. This is a batch version of Publish . For FIFO topics, multiple messages within a single batch are published in the order they are sent, and messages are deduplicated within the batch and across batches for 5 minutes.
The result of publishing each message is reported individually in the response. Because the batch request can result in a combination of successful and unsuccessful actions, you should check for batch errors even when the call returns an HTTP status code of 200 .
The maximum allowed individual message size and the maximum total payload size (the sum of the individual lengths of all of the batched messages) are both 256 KB (262,144 bytes).
Some actions take lists of parameters. These lists are specified using the param.n notation. Values of n are integers starting from 1. For example, a parameter list with two elements looks like this:
&AttributeName.1=first
&AttributeName.2=second
If you send a batch message to a topic, Amazon SNS publishes the batch message to each endpoint that is subscribed to the topic. The format of the batch message depends on the notification protocol for each subscribed endpoint.
When a messageId is returned, the batch message is saved and Amazon SNS immediately delivers the message to subscribers.
See also: AWS API Documentation
Request Syntax
client.publish_batch(
TopicArn='string',
PublishBatchRequestEntries=[
{
'Id': 'string',
'Message': 'string',
'Subject': 'string',
'MessageStructure': 'string',
'MessageAttributes': {
'string': {
'DataType': 'string',
'StringValue': 'string',
'BinaryValue': b'bytes'
}
},
'MessageDeduplicationId': 'string',
'MessageGroupId': 'string'
},
]
)
string
[REQUIRED]
The Amazon resource name (ARN) of the topic you want to batch publish to.
list
[REQUIRED]
A list of PublishBatch request entries to be sent to the SNS topic.
(dict) --
Contains the details of a single Amazon SNS message along with an Id that identifies a message within the batch.
Id (string) -- [REQUIRED]
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 (string) -- [REQUIRED]
The body of the message.
Subject (string) --
The subject of the batch message.
MessageStructure (string) --
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 (e.g. http).
MessageAttributes (dict) --
Each message attribute consists of a Name , Type , and Value . For more information, see Amazon SNS message attributes in the Amazon SNS Developer Guide.
(string) --
(dict) --
The user-specified message attribute value. For string data types, the value attribute has the same restrictions on the content as the message body. For more information, see Publish .
Name, type, and value must not be empty or null. In addition, the message body should not be empty or null. All parts of the message attribute, including name, type, and value, are included in the message size restriction, which is currently 256 KB (262,144 bytes). For more information, see Amazon SNS message attributes and Publishing to a mobile phone in the Amazon SNS Developer Guide.
DataType (string) -- [REQUIRED]
Amazon SNS supports the following logical data types: String, String.Array, Number, and Binary. For more information, see Message Attribute Data Types .
StringValue (string) --
Strings are Unicode with UTF8 binary encoding. For a list of code values, see ASCII Printable Characters .
BinaryValue (bytes) --
Binary type attributes can store any binary data, for example, compressed data, encrypted data, or images.
MessageDeduplicationId (string) --
This parameter applies only to FIFO (first-in-first-out) topics.
The token used for deduplication of messages within a 5-minute minimum deduplication interval. If a message with a particular MessageDeduplicationId is sent successfully, subsequent messages 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 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 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.
The length of MessageDeduplicationId is 128 characters.
MessageDeduplicationId can contain alphanumeric characters (a-z, A-Z, 0-9) and punctuation (!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~) .
MessageGroupId (string) --
This parameter applies only to FIFO (first-in-first-out) 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 don't provide a MessageGroupId , the action fails.
The length of MessageGroupId is 128 characters.
MessageGroupId can contain alphanumeric characters (a-z, A-Z, 0-9) and punctuation (!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~) .
Warning
MessageGroupId is required for FIFO topics. You can't use it for standard topics.
dict
Response Syntax
{
'Successful': [
{
'Id': 'string',
'MessageId': 'string',
'SequenceNumber': 'string'
},
],
'Failed': [
{
'Id': 'string',
'Code': 'string',
'Message': 'string',
'SenderFault': True|False
},
]
}
Response Structure
(dict) --
Successful (list) --
A list of successful PublishBatch responses.
(dict) --
Encloses data related to a successful message in a batch request for topic.
Id (string) --
The Id of an entry in a batch request.
MessageId (string) --
An identifier for the message.
SequenceNumber (string) --
This parameter applies only to FIFO (first-in-first-out) topics.
The large, non-consecutive number that Amazon SNS assigns to each message.
The length of SequenceNumber is 128 bits. SequenceNumber continues to increase for a particular MessageGroupId .
Failed (list) --
A list of failed PublishBatch responses.
(dict) --
Gives a detailed description of failed messages in the batch.
Id (string) --
The Id of an entry in a batch request
Code (string) --
An error code representing why the action failed on this entry.
Message (string) --
A message explaining why the action failed on this entry.
SenderFault (boolean) --
Specifies whether the error happened due to the caller of the batch API action.