Inbound messaging
Within an open conversation window, recipients can reply to your WhatsApp messages. To receive
those inbound messages and the status events for your outbound messages, you turn on message and
event publishing for your WhatsApp phone number and point it at an Amazon SNS topic. Your application
reads the topic and replies with SendWhatsAppMessage while the window is open.
Step 1: Route inbound messages to an Amazon SNS topic
Message and event publishing sends both inbound messages and outbound status events to a standard Amazon SNS topic that you own. You can turn it on while adding the phone number (see Step 2: Add a WhatsApp business phone number) or afterward on the phone number's settings.
To route inbound WhatsApp messages to an SNS topic
Open the AWS End User Messaging console at https://console.aws.amazon.com/end-user-messaging/
. Under Social messaging, choose WhatsApp business accounts, choose your WABA, and then choose the phone number.
Turn on Message and event publishing.
For the destination, choose a new or existing standard Amazon SNS topic. FIFO topics are not supported.
Save the phone number settings.
Note
Amazon SNS standard topics deliver with best-effort ordering, so inbound messages are not guaranteed to arrive in the order they were sent. If your application needs ordered processing, use the timestamp in each record to order messages at the application layer.
Step 2: Consume inbound messages and reply
Subscribe a consumer to the Amazon SNS topic – for example an Lambda function, an Amazon SQS queue,
or an HTTPS endpoint. Each inbound message and status event is delivered to the topic as a record.
When a record is an inbound message from a customer, your application can reply with
SendWhatsAppMessage. While the conversation window the customer opened is still active,
you can send free-form messages (set the message type to text or another
supported type) without a template; once the window closes, you must start a new conversation with
an approved template.
For the event-record format and the full set of event destinations, see Event destinations in AWS End User Messaging.
