Amazon SNS - Publish Message

Overview

You can use this Snap to send a message to an Amazon SNS topic. The message can be a text message (SMS message) directly to a phone number, or a message to a mobile platform endpoint (when you specify the TargetArn). If you send a message to a topic, Amazon SNS delivers the message to each endpoint that is subscribed to the topic.

When you use this Snap to publish a message, that message can be consumed through various means, including subscription through the SQS Consumer Snap, email, or HTTP endpoint. If the message is under 256 KB, you can view it directly in the output preview. However, if it exceeds 256 KB, the message's content does not display. Instead, a reference to the message is provided, typically in the form of an array of JSON objects containing an S3 Key and S3 Bucket Name. To read the message, use the S3 File Reader, Email Reader , S3 Download, or S3 Select Snaps downstream of the Publish Message Snap.


Amazon SNS - Publish Message Snap

Supported Accounts

Prerequisites

  • Valid AWS Account and SNS access.
  • Authentication such as IAM Role access, Access key, and Security Access key.
  • Create a topic and subscribe to a topic for an endpoint (SQS/Email/Email-JSON, and so on) before performing the Publish Message action.
  • Set the Attribute Name in Amazon SNS - Set Subscription Attribute to FilterPolicy if you want to select Number, String, or String Array data types under Message attributes in the Publish Message Snap.

Limitations

The SnapLogic user interface (UI) has a maximum limit of 200 MB on the size of messages you can copy in the Message field of the Publish Message Snap. If the message size exceeds this limit, the Snap fails and displays an error message stating that the: 'update' command document is too large.

Work-around: To publish messages greater than 200 MB, you can use upstream Snaps and input the message into the Publish Message Snap.

Known Issues

The Snap's performance might decrease if you do not provide a value in the Region field. As a workaround, provide a value in the Region field for optimal performance of the Snap.

Snap views

Type Description Examples of upstream and downstream Snaps
Input

Document. This Snap has at most one document input view.

Region, ARN of the topic, and the text message that you want to publish.
Output

Document. This Snap has at most one document output view.

Published message.
Learn more about Error handling.

Snap settings

Note: Learn about the common controls in the Snap settings dialog.
Field/Field set Description

Label

String

 Required.Specify a unique name for the Snap. Modify this to be more appropriate, especially if there are more than one of the same Snap in the pipeline.

Default value: Publish Message

Example: Publish Order Notification
Region

String/Expression

Specify the AWS region where the application is implemented. If the region field is not present, then the region is evaluated in the following sequence:

  • The Topic ARN or Subscription ARN
  • The region of the EC2 instance.

Default value: None

Example: us-east-1, us-west-1
Topic ARN

String/Expression

Required. Specify the Amazon Resource Name (ARN) of the topic.

If you enable expression for Topic ARN, then the Message group ID and Deduplicate ID fields are populated.

Default value: N/A

Example: Topic 1
Subject

String/Expression

Specify the subject line to be included while delivering the messages.

Default value: None

Example: Order shipped
Message Structure

Dropdown list

Select one of the following options to provide the structure or type of the message that you want to publish:

  • JSON
  • TEXT

If the property is set to JSON, then the Customized Messages field set and Message property are enabled. You can send messages to various protocols using the field set.

Default value: TEXT

Example: JSON
Message

String/Expression

Specify the message you want to publish.

It is mandatory to enter the default message if the Message Structure is set to JSON. The Snap displays an error when you do not provide a default message in the protocol.

Default value: N/A

Example: Message to publish
Customized Messages

Appears when you select JSON in the Message Structure field. You can add any number of messages by clicking the Add icon on the field set.
Protocol

String/Expression/ Suggestion

Specify the internet protocol to connect to the Amazon server. Alternatively, click the Suggestion icon to fetch a list of attribute names associated with the entity type. Available options are:

  • default
  • http
  • https
  • email
  • email-json
  • SQS
  • sms

Default value: default

Example: https
Message

String/Expression

Specify the message you want to publish.

It is mandatory to enter the default message if the Message Structure is set to JSON. The Snap displays an error when you do not provide a default message in the protocol.

Default value: N/A

Example: Message to publish
Message group ID

String/Expression

Displayed when you enable expression for Topic ARN.

Specify a tag that indicates which message group this message belongs to. The field is used and required by a FIFO queue. Messages in the same message group are delivered in the order that they are published.

Default value: N/A

Example: 5
Deduplicate ID

String/Expression

Displayed when you enable expression for Topic ARN.

Specify the token used for de-duplication of sent messages in a FIFO queue. This ID is optional if you enabled the Content-based message deduplication setting for the topic. The property is used by a FIFO queue only.

Default value: N/A

Example: 2
Message attributes

Specify the table of the message attributes. Message attributes are structured metadata for the message to help the consumer identify how to deal with the message without having to read the message body. Each message can have up to 10 attributes. The value type is string.
Attribute Name

String/Expression

Specify the name for the message attribute. By default, this field is expression enabled.

Default value: N/A

Example: Number
Data type

String/Expression/Dropdown list

Specify the data type of the message attribute. Available options are:

  • Number
  • String
  • String Array
  • Binary

You must set the Attribute Name in the Amazon SNS - Set Subscription Attribute Snap to FilterPolicy if you select Number, String, or String Array data types in the Publish Message Snap.

Default value: Number

Example: String
Attribute Value

String/Expression

Specify the value for the message attribute. By default, this field is expression enabled.

Default value: N/A

Example: snap.instanceId

Snap execution

Dropdown list
Choose one of the three modes in which the Snap executes. Available options are:
  • Validate & Execute: Performs limited execution of the Snap and generates a data preview during pipeline validation. Subsequently, performs full execution of the Snap (unlimited records) during pipeline runtime.
  • Execute only: Performs full execution of the Snap during pipeline execution without generating preview data.
  • Disabled: Disables the Snap and all Snaps that are downstream from it.

Default value: Execute only

Troubleshooting

Error Cause Resolution
Missing Topic ARN. A topic ARN value is not provided. Specify the topic ARN and retry.
No default entry in JSON message body. The Message field is empty while Message Attribute is set to JSON. Enter the message in the Message field.
An error occurred when publishing a message to the specific topic in the Amazon SNS. Failed to store the message content in an S3 object. Check the input data, formats and retry.