// WhatsApp Business API - Java Example

import java.net.HttpURLConnection;
import java.net.URL;

public class WhatsAppAPI {

    public static void main(String[] args)
            throws Exception {

        String accessToken =
            "YOUR_ACCESS_TOKEN";

        String phoneNumberId =
            "YOUR_PHONE_NUMBER_ID";

        String url =
            "https://graph.facebook.com/vXX.X/"
            + phoneNumberId
            + "/messages";

        URL apiUrl = new URL(url);

        HttpURLConnection connection =
            (HttpURLConnection)
            apiUrl.openConnection();

        connection.setRequestMethod("POST");

        connection.setRequestProperty(
            "Authorization",
            "Bearer " + accessToken
        );

        connection.setRequestProperty(
            "Content-Type",
            "application/json"
        );

        connection.setDoOutput(true);

        String json = """
        {
          "messaging_product": "whatsapp",
          "to": "RECIPIENT_PHONE_NUMBER",
          "type": "template",
          "template": {
            "name": "hello_world",
            "language": {
              "code": "en_US"
            }
          }
        }
        """;

        connection
            .getOutputStream()
            .write(json.getBytes());

        int responseCode =
            connection.getResponseCode();

        System.out.println(
            "Response: " + responseCode
        );
    }
}

// WhatsApp Business API - Node.js Example

const axios = require("axios");

const accessToken =
    "YOUR_ACCESS_TOKEN";

const phoneNumberId =
    "YOUR_PHONE_NUMBER_ID";

const recipient =
    "RECIPIENT_PHONE_NUMBER";

axios.post(

    `https://graph.facebook.com/vXX.X/`
    + `${phoneNumberId}/messages`,

    {
        messaging_product: "whatsapp",

        to: recipient,

        type: "template",

        template: {

            name: "hello_world",

            language: {
                code: "en_US"
            }
        }
    },

    {
        headers: {

            Authorization:
                `Bearer ${accessToken}`,

            "Content-Type":
                "application/json"
        }
    }

)

.then(response => {

    console.log(
        response.data
    );

})

.catch(error => {

    console.error(
        error.response?.data
        || error.message
    );

});

# WhatsApp Business API - Python Example

import requests

access_token = \
"YOUR_ACCESS_TOKEN"

phone_number_id = \
"YOUR_PHONE_NUMBER_ID"

recipient = \
"RECIPIENT_PHONE_NUMBER"

url = \
f"https://graph.facebook.com/vXX.X/" \
f"{phone_number_id}/messages"

headers = {

    "Authorization":
        f"Bearer {access_token}",

    "Content-Type":
        "application/json"
}

data = {

    "messaging_product":
        "whatsapp",

    "to":
        recipient,

    "type":
        "template",

    "template": {

        "name":
            "hello_world",

        "language": {

            "code":
                "en_US"
        }
    }
}

response = requests.post(

    url,

    headers=headers,

    json=data
)

print(
    response.json()
)