To get delivery status and incoming WhatsApp Messages, you need to set webhook endpoints in CRM Messaging Developer Console Text Messaging for Marketers and Sales Reps – CRM Messaging (crm-messaging.cloud)
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Delivery Status Payload
You will get real time updates on your delivery webhook endpoint with message status as sent, delivered and read in status field.
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In case your message fails to deliver, you will get response with error code as shown below
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Error code description can be found on Facebook Whatsapp error logs (1) Error Codes – WhatsApp Business Platform Cloud API (facebook.com)
Incoming WhatsApp Message
For each incoming Whatsapp message, you will be notified on the incoming webhook with payload looking like,
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Note that msg field will have message body and media field will have a media attachment URL.