Send a WhatsApp message with failover

In this example you will send a WhatsApp message that fails over to sending an SMS.

In the Workflow object, message objects can be placed in any order to suit your use case. Each message object must contain a failover object, except for the last message, as there are no more message objects to failover to.

NOTE: The first time you send a message to a user, WhatsApp requires that the message contains a template. This is explained in more detail in the Understanding WhatsApp topic.

Example

Ensure the following variables are set to your required values using any convenient method:

Key Description
VONAGE_APPLICATION_ID The Vonage Application ID.
FROM_NUMBER Replace with number you are sending from. E.g. 447700900002
TO_NUMBER Replace with the number you are sending to. E.g. 447700900001
WHATSAPP_NUMBER The WhatsApp number that has been allocated to you by Vonage. For sandbox testing the number is 14157386170.

NOTE: Don't use a leading + or 00 when entering a phone number, start with the country code, for example 447700900000.

Prerequisites

If you do not have an application you can create one. Make sure you also configure your webhooks.

Write the code

Add the following to send-whatsapp-message-with-failover.sh:

curl -X POST https://api.nexmo.com/v0.1/dispatch \
  -H 'Authorization: Bearer '$JWT\
  -H 'Content-Type: application/json' \
  -H 'Accept: application/json' \
  -d $'{
    "template":"failover",
    "workflow": [
      {
        "from": { "type": "whatsapp", "number": '$WHATSAPP_NUMBER' },
        "to": { "type": "whatsapp", "number": '$TO_NUMBER' },
        "message": {
          "content": {
            "type": "text",
            "text": "This is a WhatsApp Message sent via the Dispatch API"
          }
        },
        "failover":{
          "expiry_time": 600,
          "condition_status": "read"
        }
      },
      {
        "from": {"type": "sms", "number": '$FROM_NUMBER'},
        "to": { "type": "sms", "number": '$TO_NUMBER'},
        "message": {
          "content": {
            "type": "text",
            "text": "This is an SMS sent via the Dispatch API"
          }
        }
      }
    ]
  }'

View full source

Run your code

Save this file to your machine and run it:

bash send-whatsapp-message-with-failover.sh

Prerequisites

If you do not have an application you can create one. Make sure you also configure your webhooks.

npm install @vonage/server-sdk@beta

Write the code

Add the following to send-failover-whatsapp-sms.js:

const Vonage = require("@vonage/server-sdk");

const vonage = new Vonage({
  apiKey: VONAGE_API_KEY,
  apiSecret: VONAGE_API_SECRET,
  applicationId: VONAGE_APPLICATION_ID,
  privateKey: VONAGE_APPLICATION_PRIVATE_KEY_PATH
});

vonage.dispatch.create(
  "failover",
  [
    {
      from: { type: "whatsapp", number: WHATSAPP_NUMBER },
      to: { type: "whatsapp", number: TO_NUMBER },
      message: {
        content: {
          type: "text",
          text: "Dispatch API: Message 1"
        }
      },
      failover: {
        expiry_time: 60,
        condition_status: "read"
      }
    },
    {
      from: { type: "sms", number: FROM_NUMBER },
      to: { type: "sms", number: TO_NUMBER },
      message: {
        content: {
          type: "text",
          text: "Dispatch API: Message 2"
        }
      }
    }
  ],
  (err, data) => {
    if (err) {
      console.error(err);
    } else {
      console.log(data.dispatch_uuid);
    }
  }
);

View full source

Run your code

Save this file to your machine and run it:

node send-failover-whatsapp-sms.js

Try it out

When you run the code it will attempt to send a message via WhatsApp. If this fails then a message will be sent via SMS to the destination number.