AWS SNS how to add line breaks in message - json

Question

I'm trying to send SNS messages via CLI in json format.
aws sns publish --cli-input-json "{\"TopicArn\":\"xxx\",\"Message\":\"first line\n second line\",\"Subject\":\"Empty subject\"}"
But the \n doesn't work. Neither is "\r\n" or "\n". I think the string is escaped by SNS so \n doesn't work. Does anyone know how to send a message of 2 lines?(Sending 2 messages is not an option) Appreciate your advice!

Answer 1

I think \\n is actually what you are looking for. I've just tested it by sending push notifications to my device through AWS SNS.
So your message should look like this:
aws sns publish --cli-input-json "{\"TopicArn\":\"xxx\",\"Message\":\"first line\\nsecond line\",\"Subject\":\"Empty subject\"}"
Note, you should not leave the white space after the line break symbol, otherwise, your new line would start with that space.

Answer 2

aws sns publish --topic-arn "arn:aws:sns:us-west-2:0123456789012:my-topic" --message file://message.txt
message.txt is a text file containing the message to publish:
Hello World
Second Line
Putting the message in a text file allows you to include line breaks
.

Answer 3

This worked out for me:
"first line
second line"

Answer 4

I am publishing messages using the email protocol using the NodeJs aws-sdk. In order for exceptions to appear correctly, I needed to replace both \n and \\n, and to appease both windows and mac clients, used \r\n.
message.replace(/\n|\\n/g, '\r\n')
For anyone who needs full code, this is how I am handling errors in typescript
public prepareMessage(header: string, error: any) {
const data = (error instanceof Error)
? JSON.stringify(error, Object.getOwnPropertyNames(error), 2)
: JSON.stringify(error, null, 2);
const replaceNewlines = (str: string) => str?.replace(/\n|\\n/g, '\r\n') || '';
return `${replaceNewlines(header)}\r\n${replaceNewlines(data)}`;
}

Answer 5

four backslash
works for me
using Aws SNS with Firebase
EX: backslashbackslashbackslashbackslash+n

Answer 6

After testing all suggested answers, here's what worked in my case (running from a python lambda function, publishing from boto3 sns client):
This created 2 new lines: message.replace('\n', '\r\n')
This created 1 new line: message.replace('\n', '\r')
Example:
message = message.replace('\n', '\r').replace('\t', ' ')
# Sending the notification...
snsclient.publish(
TargetArn=SNS_EMAIL_ALERTS_ARN,
Subject=f'{filter_name} Alert: ({lambda_func_name[3]})',
Message=message
)