Post Syndicated from Rommel Sunga original https://aws.amazon.com/blogs/messaging-and-targeting/adding-line-messenger-to-your-aws-omnichannel-fallback-solution/

In this post, you will learn how to extend an existing omnichannel fallback solution by integrating LINE Messenger, including architecture updates, deployment steps, and testing procedures. The original solution, built with Amazon API Gateway, AWS Lambda, Amazon Simple Email Service (Amazon SES), and AWS End User Messaging, delivers messages across SMS, WhatsApp, and email with automatic fallback capabilities.

For more information about the original omnichannel fallback solution that this aims to extend to LINE, see the Enhancing Message Reach: An Omnichannel Approach Using WhatsApp, SMS, and Email with AWS.

Why LINE Messenger?

LINE is a popular messaging platform in Japan, Taiwan, and Thailand, with 181 million monthly active users across its primary markets, including 100 million in Japan alone (LY Corporation FY2025 Q3 earnings data). With an 84 percent DAU/MAU ratio (88 percent in Japan), LINE sees high daily engagement, making it a reliable channel for time-sensitive communications such as appointment reminders in healthcare, order and shipping notifications in ecommerce, and promotional campaigns in retail.

While other messaging platforms are popular in specific APAC markets (KakaoTalk in South Korea, WeChat in China, Zalo in Vietnam, Viber in the Philippines), LINE holds a strong position across Japan, Taiwan, and Thailand simultaneously, making it a high-impact addition to a multi-channel messaging strategy for those countries. By adding LINE to the omnichannel fallback solution, you can reach your audience on their preferred messaging channel in these key markets. You can use LINE as either a primary or fallback channel while maintaining the same fallback and broadcast patterns already available for other channels.

Cost note: LINE Messaging API pricing varies by country and plan. See the pricing pages for LINE Messaging API, Amazon Simple Email Service (Amazon SES), and Amazon End User Messaging for details on each channel.

Architecture overview

Adding LINE to your fallback solution means you can now cover four major messaging channels from a single API endpoint, giving you broader reach without added operational complexity. The LINE integration follows the same event-driven serverless pattern as the existing channels. The following diagram shows the key additions to the architecture.

Figure 1: Updated omnichannel architecture with LINE Messenger (new components highlighted)

You can now reach LINE users with two straightforward additions to the existing architecture:

LINE Messaging API Integration – The Primary and Secondary Handler Lambda functions now include a send_line module that calls the LINE Messaging API to deliver messages using the Push Message endpoint.

AWS Secrets Manager Integration – LINE channel credentials (access token and channel secret) are stored securely in AWS Secrets Manager and retrieved by Lambda functions with caching for performance.

How LINE integration works

The LINE Messenger integration extends the existing message processing pipeline, so you get the same reliable fallback behavior that you already have for email, SMS, and WhatsApp. The following sections describe how the system handles LINE messages and fallback scenarios.

Sending a LINE message

When you send a message with LINE as the primary or fallback channel, the flow follows the same pattern as other channels with LINE-specific handling:

1. API Gateway receives the request and places it in the Primary Amazon Simple Queue Service (Amazon SQS) Queue.
2. The Primary Handler Lambda detects the channel as “line” and invokes the send_line module.
3. The send_line module retrieves LINE credentials from Secrets Manager (cached for performance) and sends a request to the LINE Messaging API Push Message endpoint. The Push Message API sends messages to LINE users without requiring the user to message first. The request body contains a to field with the recipient’s LINE User ID (a unique identifier assigned when a user follows your LINE Official Account) and a messages array with the message objects to deliver. The module validates the recipient LINE User ID against the expected format (a capital ‘U’ followed by 32 lowercase hexadecimal characters) before invoking the LINE API. Requests with malformed recipient IDs are rejected early and don’t reach the external API.
4. The Lambda function records the message status in the Amazon DynamoDB table.
5. If fallback is configured, the Lambda function enqueues the message to the Fallback Queue. This happens regardless of whether the LINE API call succeeds (HTTP 200) or fails (non-200 response, timeout, or exception). DynamoDB records the message status as delivered on success or failed on failure. The Secondary Handler checks DynamoDB and sends through the fallback channel if the status isn’t delivered.
6. The Secondary Handler updates the DynamoDB status to sent_fallback.

How LINE differs from other channels

LINE uses an external API with its own authentication rather than AWS-native IAM authentication. This means you must manage credentials through AWS Secrets Manager rather than relying on AWS Identity and Access Management (IAM)-managed authentication. For more information, see the LINE Messaging API documentation.

LINE offers two distinct messaging products for businesses, LINE Messaging API, and LINE Official Notification.

• The LINE Messaging API, which is the focus of this guide, supports two-way conversational messaging and is widely adopted across industries for use cases such as mobile ordering, loyalty programs, and customer engagement. LINE also offers LINE Official Notification (also known as LINE Notification Messages), a separate service designed for one-way transactional notifications such as shipping updates and appointment reminders, which requires business verification.
• LINE Official Notification provides per-message delivery completion events, but the LINE Messaging API doesn’t. With the Messaging API, an HTTP 200 response confirms LINE accepted the message for delivery, and this is the most granular delivery signal available.

Creating a LINE Messaging API Channel

You need a LINE Messaging API Channel to authenticate and send messages through the LINE integration. The following steps walk you through creating one:

1. Sign in to the LINE Developers Console. Create a personal LINE account if you don’t have one already and download the corresponding iOS/Android/PC application. This is required to test receiving LINE messages.
2. Create a Provider (your company/org name).
   
3. Create a new Messaging API channel under that provider.
   
4. After you create the channel, enable the Messaging API from the LINE Official Account Manager page.
   
5. From the channel settings, note the following:
   1. Channel access token (Messaging API tab, then select Issue)
      
      
   2. Channel secret (Basic settings tab)
      
6. Disable Auto-reply and Greeting messages under Messaging API settings.
   

Deploying and testing

The repository includes a complete deployment guide with step-by-step instructions for deploying the CDK stack, configuring LINE credentials in AWS Secrets Manager, obtaining personal LINE user IDs, and running the integration test suite. The test suite automatically detects which channels are configured and runs the applicable tests. For full deployment and testing instructions, see the Deployment Guide in the repository.

Security considerations

Before deploying this solution to production, review the following considerations and adjust for your workload and compliance obligations.

Least-privilege IAM

The Lambda execution roles in the sample scope DynamoDB, Amazon SQS, and AWS Secrets Manager permissions to specific resource ARNs. The send actions for Amazon SES (ses:SendEmail, ses:SendTemplatedEmail), SMS (sms-voice:SendTextMessage), and WhatsApp (social-messaging:SendWhatsAppMessage) are granted on resources: [“*”] in this sample for simplicity, because the specific sending identities, phone pools, and WhatsApp business accounts are left configurable. For production, scope these further where the API supports it: SES allows identity-level ARNs (for example, arn:aws:ses:region:account:identity/example.com), and End User Messaging SMS supports pool and phone-number ARNs. When adapting this code, keep resource-level scoping for everything that supports it and review the AWS Well-Architected Security Pillar and Lambda execution role guidance for production deployments.

Rotating LINE credentials

LINE channel access tokens are long-lived and are issued and rotated manually through the LINE Developers Console; there’s no programmatic rotation API. Rotate the token periodically in line with your organization’s key-rotation policy (for example, every 90 days), update the Secrets Manager secret with the new value, and force a Lambda cold start (by redeploying the stack or updating a Lambda environment variable) so the cached credentials are refreshed.

Data protection and PII retention

The solution stores message metadata and recipient identifiers (including LINE User IDs, phone numbers, and email addresses) in Amazon DynamoDB. DynamoDB uses AWS-managed encryption at rest, Secrets Manager uses AWS Key Management Service (AWS KMS), and all outbound calls to the LINE API are made over HTTPS. Point-in-time recovery is enabled on the message table.

The sample doesn’t configure a DynamoDB Time-to-Live (TTL) attribute, so records persist indefinitely. For production, add a TTL attribute (for example, expiresAt) that matches your retention policy, and review whether the RemovalPolicy.RETAIN setting on the tables is appropriate for your environment. LINE User IDs, phone numbers, and email addresses are personally identifiable information under regulations including Japan’s APPI, the EU’s GDPR, and similar laws. Assess your retention obligations, data residency requirements, and processes for handling subject access and deletion requests for the regions you serve.

Conclusion

By adding LINE Messenger to the omnichannel fallback solution, you can now reach your customers across the four messaging channels that matter most: email, SMS, WhatsApp, and LINE. The integration follows the same serverless, event-driven patterns as the existing channels, making it straightforward to deploy and maintain. LINE can serve as either a primary or fallback channel, giving you the flexibility to tailor your messaging strategy to regional preferences. As a next step, consider adding other regional messaging services to further expand your reach. You can also explore advanced LINE features such as rich messages, quick replies, and Flex Messages to create more engaging customer interactions.

Resources

• GitHub Repository
• Enhancing Message Reach: An Omnichannel Approach Using WhatsApp, SMS, and Email with AWS
• LINE Developers Documentation
• AWS CDK Documentation

About the authors

Post Syndicated from Rommel Sunga original https://aws.amazon.com/blogs/messaging-and-targeting/send-whatsapp-business-messages-with-aws-end-user-messaging-social/

WhatsApp reaches over 3 billion monthly active users worldwide — with more than 2 billion using it every day — making it the single most direct channel for customer communication at global scale. AWS End User Messaging Social gives you a managed API to send WhatsApp Business messages without building or maintaining your own WhatsApp Business API integration.

Whether you’re building appointment reminders, order notifications, or interactive customer support flows, with WhatsApp Business messaging, you can meet customers where they already communicate.

This post is for developers and solutions architects looking to integrate WhatsApp messaging into their customer engagement workflows using AWS. By the end, you will know how to send every supported message type—from straightforward text and media to templates, interactive menus, and WhatsApp Flows—using Python and the AWS End User Messaging Social API.

Solution overview

This solution uses AWS End User Messaging Social to connect your WhatsApp Business Account (WABA) with your AWS workloads, enabling automated, two-way messaging with your customers. When a customer sends a WhatsApp message to your WABA phone number, AWS End User Messaging Social receives the message and publishes an event to an Amazon Simple Notification Service (Amazon SNS) topic. Amazon SNS then invokes an AWS Lambda function. You configure this Lambda function to process the incoming message and send a contextual WhatsApp reply to the customer. The following diagram illustrates this architecture:

Figure A: Shows the architecture flow “Customer WhatsApp → End User Messaging Social → SNS → Lambda → End User Messaging Social → Response”

IMPORTANT: Note that any WhatsApp user can send a message to your WABA number and trigger the workflow. To avoid incurring ongoing charges, complete the steps in the “Clean up” section.

The solution is deployed using the AWS Serverless Application Model (AWS SAM) and includes a sample Lambda function that demonstrates how to handle common message types, send interactive list messages, and respond with templated replies. You can extend this foundation to build more sophisticated workflows, such as invoking AWS Step Functions for multi-step processes or routing messages to container-based workloads running on AWS. AWS End User Messaging Social also provides unified billing within AWS, streamlining cost management for your WhatsApp messaging workloads.

Prerequisites

Before you run any of the examples in this post, complete the following prerequisites:

• A phone number to link a WABA.
• Connect a verified WhatsApp Business Account (WABA) to AWS End User Messaging Social.
• Install the AWS SDK for Python (Boto3).
• Optionally, install the AWS Command Line Interface (AWS CLI) for template creation (otherwise the templates must be created within the AWS Console UI or Meta’s WhatsApp Manager).
• A phone with WhatsApp Messenger app installed to test the solution. Note that the mobile app uses a different phone number than the one that is associated with your WABA.

This walkthrough typically takes 30–45 minutes, though actual time might vary based on your familiarity with AWS services and WhatsApp Business configuration.

If you’re new to AWS End User Messaging Social, see the Getting Started with WhatsApp guide before proceeding.

IAM permissions

To configure AWS End User Messaging Social, you will need several types of permissions depending on what you’re setting up. Here are the key permissions required:

Core AWS End User Messaging social permissions

For basic configuration and management, you will need permissions for the following actions:

• social-messaging:AssociateWhatsAppBusinessAccount — to associate a WhatsApp Business Account with your AWS account
• social-messaging:CreateWhatsAppMessageTemplate — to create WhatsApp message templates
• social-messaging:ListLinkedWhatsAppBusinessAccounts — to list linked WhatsApp Business Accounts
• social-messaging:GetWhatsAppMessageTemplate — to retrieve message template details
• social-messaging:ListWhatsAppMessageTemplates — to list message templates

For event destinations (SNS integration)

If you’re configuring event destinations with Amazon SNS, your SNS topic must have a resource policy allowing the sms-voice.amazonaws.com service principal to publish to it, and you will need an AWS Identity and Access Management (IAM) role with a trust policy allowing social-messaging.amazonaws.com to assume it. For detailed setup instructions, see Configuring Event Destinations in the AWS End User Messaging Social User Guide.

For Amazon Connect integration

If integrating with Amazon Connect, the service-linked role (SLR) includes the following permissions:

• social-messaging:SendWhatsAppMessage
• social-messaging:PostWhatsAppMessageMedia
• social-messaging:GetWhatsAppMessageMedia
• social-messaging:GetLinkedWhatsAppBusinessAccountPhoneNumber

For more information, see Amazon Connect Service-Linked Role in the Amazon Connect Administrator Guide.

Additional considerations

• If using encrypted SNS topics with AWS KMS, you will need additional AWS Key Management Service (AWS KMS) permissions for the service to generate and decrypt data keys.

Configuration

Create a config.json file in your project directory with the following structure to store the destination WhatsApp number and the origination phone number ID (for example, phone-number-id-a1b2c3d4######) that we’re sending messages from and receiving the message:

{
    "originationPhoneNumberId": "your-whatsapp-phone-number-id",
    "destinationPhoneNumber": "+1234567890"
}

Security note: The config.json file is intended for local testing only. In production environments, avoid hardcoding phone numbers and credentials. Instead, use AWS Secrets Manager, AWS Systems Manager Parameter Store, or environment variables to manage sensitive configuration values.

Each example builds a message_data payload and sends it using the following code:

import json
import boto3
import os

config_path = os.path.join(os.path.dirname(__file__), 'config.json')
with open(config_path, 'r') as f:
    config = json.load(f)

client = boto3.client('socialmessaging')
message_data = { ... }

response = client.send_whatsapp_message(
    message=json.dumps(message_data),
    originationPhoneNumberId=config['originationPhoneNumberId'],
    metaApiVersion="v20.0"
)
print(f"Message sent successfully! Response: {response}")

For production use, wrap the send call with error handling to manage throttling and failures gracefully:

try:
    result = client.send_whatsapp_message(
        message=json.dumps(message_data),
        originationPhoneNumberId=config['originationPhoneNumberId'],
        metaApiVersion="v20.0"
    )
    print(f"Message sent. ID: {result['messageId']}")
except client.exceptions.ThrottlingException as e:
    print(f"Rate limited. Retry after backoff: {e}")
except Exception as e:
    print(f"Failed to send message: {e}")

The following sections show only the message_data for each message type. To send any of these messages, use the shared sending code from the previous Configuration section—load config.json, create the Boto3 client, and call client.send_whatsapp_message() with the payload.

Text messages

Text messages are plain text communications sent within the 24-hour conversation window. They don’t require Meta template approval and support basic formatting.

Specifications and requirements

Text messages are the foundation of WhatsApp conversations. You can send up to 4,096 characters per message. Text messages don’t require Meta approval and work within an active 24-hour conversation window that opens when a customer messages your business first, or when you initiate contact using an approved template.

• Maximum length: 4,096 characters (including spaces and formatting)
• 24-hour window requirement: Can only be sent within 24 hours of last customer message
• No WhatsApp template approval required

WhatsApp message example

The following image is a WhatsApp message example.

Code example

The following is a code example for the previous message.

message_data = {
    "messaging_product": "whatsapp",
    "to": config['destinationPhoneNumber'],
    "type": "text",
    "text": {
        "body": "For the Classic T-Shirt, we recommend size Medium based on your measurements. It runs true to size with a regular fit. Size Medium: Chest 38-40 inches, Length 28 inches."
    }
}

Media messages

With Media messages, you can send images, documents, audio, and video files.

Specifications and requirements

• Images: Maximum 5 MB (JPEG, PNG)
• Documents: Maximum 100 MB (PDF, DOC, DOCX, PPT, PPTX, XLS, XLSX)
• Audio: Maximum 16 MB (AAC, MP4, AMR, MP3, OGG)
• Video: Maximum 16 MB (MP4, 3GPP)

Note: Media uploaded to Meta is retained for 30 days. If you reuse media across messages (such as a company logo), use the external URL method or re-upload before sending. The examples in this post use external URLs.

Media (document) message example

The message is presented as a PDF with the provided message body in the following example.

Code example

The following is a code example for the previous message.

message_data = {
    "messaging_product": "whatsapp",
    "to": config['destinationPhoneNumber'],
    "type": "document",
    "document": {
        "link": "https://docs.aws.amazon.com/pdfs/social-messaging/latest/userguide/social-ug.pdf",
        "caption": "\U0001F4C4 Your invoice #12345 is ready. Payment due: January 31, 2024. Questions? Reply to this message.",
        "filename": "Invoice-12345.pdf"
    }
}

Media (image) message example

This media message includes an image with a message body in the following example to describe the image. In this case it shows a laptop available for purchase with a link included as part of the message body.

Code example

The following is a code example for the previous message.

message_data = {
    "messaging_product": "whatsapp",
    "to": config['destinationPhoneNumber'],
    "type": "image",
    "image": {
            "link": "https://signin.aws.amazon.com/v2/assets/_next/static/media/[email protected]",
            "caption": "Thanks for reaching out to AnyCompany! Here's the product image for the laptop you inquired about. Feel free to reply if you need more details."
    }
}

Template messages

Template messages enable business-initiated conversations outside the 24-hour window. Templates must be created and approved by Meta before use.

Text template message creation with parameters

Template creation using CLI

While it’s possible to create templates directly in the AWS End User Messaging Social console and in WhatsApp Manager’s UI, you can also use AWS End User Messaging Social to programmatically create templates using the AWS CLI.

Step 1 — Create a file named order_confirmation_template.json in your working directory with the following template definition.

{
    "name": "order_confirmation_template",
    "language": "en",
    "category": "UTILITY",
    "parameter_format": "named",
    "components": [
      {
        "type": "HEADER",
        "format": "TEXT",
        "text": "Order {{order_number}}",
        "example": {
          "header_text_named_params": [
            {"param_name": "order_number", "example": "ORD-2025-001"}
          ]
        }
      },
      {
        "type": "BODY",
        "text": "Hi {{customer_name}},\n\nYour order has been confirmed!\n\nItem: {{item_name}}\nTotal: {{total_amount}}\nEstimated Delivery: {{delivery_date}}\n\nThank you for shopping
  with us!",
        "example": {
          "body_text_named_params": [
            {"param_name": "customer_name", "example": "John Smith"},
            {"param_name": "item_name", "example": "Wireless Headphones"},
            {"param_name": "total_amount", "example": "$179.17"},
            {"param_name": "delivery_date", "example": "November 30, 2025"}
          ]
        }
      }
    ]
  }

Step 2 — Run the following CLI command to create the template. Note that the –template-definition parameter points to the local JSON file that contains the template structure:

aws socialmessaging create-whatsapp-message-template \

    --region [AWS_REGION] \
    --cli-binary-format raw-in-base64-out \
    --id [WABA_ID] \
    
--template-definition file://order_confirmation_template.json

Template creation using the console

AWS End User Messaging Social also features a built-in template management UI which you can use to create and manage templates directly within the AWS End User Messaging Social portion of the AWS Console under AWS End User messaging > Social Messaging > Message Templates. To create a new template, choose the Create Template button.

In the first screen, you can set your template name, template language and template type for your respective WhatsApp Business Account.

In the second screen, you can set the message content for the template including variables to dynamically populate when sending the message content.

Approved message templates can be seen under the message template screen along with their approval status.

Sending the template message

After your template is approved, you can send it with parameter values populated at send time.

Important: When sending the template message, you must use the same language and locale that you used when creating the template. For example, a language code of “en” isn’t the same as “en_US”.

message_data = {
    "messaging_product": "whatsapp",
    "to": config['destinationPhoneNumber'],
    "type": "template",
    "template": {
        "name": "order_confirmation_template",
        "language": {"code": "en"},
        "components": [
            {
                "type": "header",
                "parameters": [
                    {"type": "text", "parameter_name": "order_number", "text": "ORD-2025-001"}
                ]
            },
            {
                "type": "body",
                "parameters": [
                    {"type": "text", "parameter_name": "customer_name", "text": "John Smith"},
                    {"type": "text", "parameter_name": "item_name", "text": "Wireless Headphones"},
                    {"type": "text", "parameter_name": "total_amount", "text": "$179.17"},
                    {"type": "text", "parameter_name": "delivery_date", "text": "November 30, 2025"}
                ]
            }
        ]
    }
}

Location messages

Location messages share geographic coordinates with optional name and address information. For example, you can send a location for a store branch to a customer.

Create template message with CLI

Step 1 — Create a file named store_location_template.json in your working directory with the following template definition:

{
    "name": "store_location",
    "language": "en",
    "category": "UTILITY",
    "parameter_format": "named",
    "components": [
      {
        "type": "HEADER",
        "format": "LOCATION"
      },
      {
        "type": "BODY",
        "text": "Visit our {{store_name}} store!\n\nOperating Hours: {{hours}}\n\nSee you soon!",
        "example": {
          "body_text_named_params": [
            {"param_name": "store_name", "example": "Marina Bay Store"},
            {"param_name": "hours", "example": "10 AM - 10 PM"}
          ]
        }
      }
    ]
  }

Step 2 — Run the following CLI command to create the template. The –template-definition parameter references the JSON file that you previously created:

aws socialmessaging create-whatsapp-message-template \
    --region [AWS_REGION] \
    --cli-binary-format raw-in-base64-out \
    --id [WABA_ID] \

--template-definition file://store_location_template.json

Location message example

The following image is an example of a location message.

Code example

The following is a code example of the previous location message example.

message_data = {
    "messaging_product": "whatsapp",
    "to": config['destinationPhoneNumber'],
    "type": "template",
    "template": {
        "name": "store_location",
        "language": {
            "code": "en"
        },
        "components": [
            {
                "type": "header",
                "parameters": [
                    {
                        "type": "location",
                        "location": {
                            "latitude": "1.2838",
                            "longitude": "103.8591",
                            "name": "Marina Bay Sands",
                            "address": "10 Bayfront Ave, Singapore 018956"
                        }
                    }
                ]
            },
            {
                "type": "body",
                "parameters": [
                    {
                        "type": "text",
                        "parameter_name": "store_name",
                        "text": "Marina Bay Store"
                    },
                    {
                        "type": "text",
                        "parameter_name": "hours",
                        "text": "10 AM - 10 PM"
                    }
                ]
            }
        ]
    }
}

Interactive messages

Interactive messages provide pre-defined response options through buttons or lists. These messages must be sent within the 24-hour conversation window.

• Structured responses – Pre-defined options ensure consistent data collection
• Enhanced UX – One-tap interactions reduce friction and improve completion rates
• 24-hour window requirement – Must be sent within active conversation windows

Quick reply buttons message

This example demonstrates collecting guest feedback using quick reply buttons for streamlined response collection.

Technical specifications:

• Maximum three buttons per message
• Button text limit: 20 characters
• Buttons appear in a horizontal row on most devices

Quick reply buttons message example

The following image is an example of the Quick reply buttons message.

Code example

The following is a code example of the previous example image.

message_data = {
    "messaging_product": "whatsapp",
    "recipient_type": "individual",
    "to": config['destinationPhoneNumber'],
    "type": "interactive",
    "interactive": {
        "type": "button",
        "body": {
            "text": "\U0001F3E8 Thank you for staying with us! How would you rate your experience?"
        },
        "action": {
            "buttons": [
                {
                    "type": "reply",
                    "reply": {
                        "id": "excellent",
                        "title": "\u2B50 \u2B50 \u2B50 \u2B50 \u2B50 Excellent"
                    }
                },
                {
                    "type": "reply",
                    "reply": {
                        "id": "good",
                        "title": "\u2B50 \u2B50 \u2B50 \u2B50 Good"
                    }
                },
                {
                    "type": "reply",
                    "reply": {
                        "id": "needs_improvement",
                        "title": "\u2B50 \u2B50 Needs Work"
                    }
                }
            ]
        }
    }
}

List Message

This example shows a restaurant menu using list messages for organized, scrollable content presentation.

Technical specifications:

• Max Options: Up to 10 rows total, which can be organized into 10 sections.
• Button Text: Maximum 24 characters to open the menu.
• Sections: A list can contain multiple sections (e.g., “Starters”, “Mains”).

List message example

The following is an image of a list message example.

When the user expands the list, they can select individual items to add to their cart.

Code example

The following is the code example for the previously mentioned example.

message_data = {
    "messaging_product": "whatsapp",
    "recipient_type": "individual",
    "to": config['destinationPhoneNumber'],
    "type": "interactive",
    "interactive": {
        "type": "list",
        "body": {
            "text": "\U0001F37D\uFE0F Welcome to Bella Vista! Browse our menu categories in the following list:"
        },
        "action": {
            "button": "View Menu",
            "sections": [
                {
                    "title": "Main Courses",
                    "rows": [
                        {
                            "id": "pasta",
                            "title": "\U0001F35D Pasta Dishes",
                            "description": "Fresh pasta with signature sauces"
                        },
                        {
                            "id": "pizza",
                            "title": "\U0001F355 Wood-Fired Pizza",
                            "description": "Authentic Italian pizza"
                        }
                    ]
                },
                {
                    "title": "Beverages",
                    "rows": [
                        {
                            "id": "wine",
                            "title": "\U0001F377 Wine Selection",
                            "description": "Curated Italian wines"
                        },
                        {
                            "id": "cocktails",
                            "title": "\U0001F378 Signature Cocktails",
                            "description": "Handcrafted cocktails"
                        }
                    ]
                }
            ]
        }
    }
}

Contact messages

Contact messages share vCard-formatted contact information, useful for sharing business contact details with customers.

Contact message example

The following is an image of an example contact message.

Customers can choose to directly message the contact, save the contact to their contacts list and view details about the contact in a pop up.

Code example

The following is a code example for the previously mentioned image example.

message_data = {
    "messaging_product": "whatsapp",
    "to": config['destinationPhoneNumber'],
    "type": "contacts",
    "contacts": [
        {
            "name": {
                "formatted_name": "AnyCompany Customer Support",
                "first_name": "Customer",
                "last_name": "Support"
            },
            "org": {
                "company": "AnyCompany Inc."
            },
            "phones": [
                {
                    "phone": "+1-555-0123",
                    "type": "WORK",
                    "wa_id": "15550123"
                }
            ],
            "emails": [
                {
                    "email": "[email protected]",
                    "type": "WORK"
                }
            ],
            "urls": [
                {
                    "url": "https://www.anycompany.com",
                    "type": "WORK"
                }
            ],
            "addresses": [
                {
                    "street": "123 Business Ave",
                    "city": "Seattle",
                    "state": "WA",
                    "zip": "98101",
                    "country": "United States",
                    "country_code": "US",
                    "type": "WORK"
                }
            ]
        }
    ]
}

WhatsApp Flows

WhatsApp Flows can help power interactive experiences. Note that a verified WhatsApp Business Account is required to use WhatsApp Flows. There are two general types of WhatsApp Flows:

• Without an endpoint — Results are stored and can be viewed directly within WhatsApp Manager. This is the type demonstrated in this post.
• With an endpoint — Results are sent to an API endpoint that you specify for further processing.

WhatsApp Flow – survey

This is an example of a WhatsApp Flow without an endpoint that sends a product survey to customers. Since this flow doesn’t use an endpoint, the results can be viewed directly within WhatsApp Manager.

Create WhatsApp Flow using Flow Playground

First create a WhatsApp Flow using the Flows Playground on the Meta for Developers website.

You can use the following JSON in the editor to use the example flow that we’re creating.

{"version":"7.2","screens":[{"id":"QUESTION_ONE","title":"Question 1 of 2","data":{},"layout":{"type":"SingleColumnLayout","children":[{"type":"Form","name":"form","children":[{"type":"TextHeading","text":"What product categories interest you?"},{"type":"CheckboxGroup","label":"Choose all that apply:","required":true,"name":"product_categories","data-source":[{"id":"electronics","title":"Electronics"},{"id":"fashion","title":"Fashion"},{"id":"home","title":"Home & Living"},{"id":"beauty","title":"Beauty"}]},{"type":"Footer","label":"Continue","on-click-action":{"name":"navigate","next":{"type":"screen","name":"QUESTION_TWO"},"payload":{"product_categories":"${form.product_categories}"}}}]}]}},{"id":"QUESTION_TWO","title":"Question 2 of 2","data":{"product_categories":{"type":"array","items":{"type":"string"},"__example__":[]}},"terminal":true,"success":true,"layout":{"type":"SingleColumnLayout","children":[{"type":"Form","name":"form","children":[{"type":"TextHeading","text":"What's your typical budget?"},{"type":"RadioButtonsGroup","label":"Choose one:","required":true,"name":"budget_range","data-source":[{"id":"under_50","title":"Under $50"},{"id":"50_150","title":"$50 - $150"},{"id":"over_150","title":"Over $150"}]},{"type":"Footer","label":"Submit","on-click-action":{"name":"complete","payload":{"product_categories":"${data.product_categories}","budget_range":"${form.budget_range}"}}}]}]}}]}

Afterwards you will be prompted to create the template to attach to the flow.

Create WhatsApp template using AWS CLI

Step 1 — Create a file named anycompany_survey_template.json in your working directory with the following template definition. Notice that the Flow JSON is embedded directly in the flow_json field of the button component:

{ "name": "anycompany_survey", "language": "en_US", "category": "MARKETING", "components": [ { "type": "BODY", "text": "Hi! We're AnyCompany and we'd love to personalize your shopping experience. Take our quick 2-question survey!" }, { "type": "BUTTONS", "buttons": [ { "type": "FLOW", "text": "Start Survey", "flow_json": "{"version":"7.2","screens":[{"id":"QUESTION_ONE","title":"Question 1 of 2","data":{},"layout":{"type":"SingleColumnLayout","children":[{"type":"Form","name":"form","children":[{"type":"TextHeading","text":"What product categories interest you?"},{"type":"CheckboxGroup","label":"Choose all that apply:","required":true,"name":"product_categories","data-source":[{"id":"electronics","title":"Electronics"},{"id":"fashion","title":"Fashion"},{"id":"home", "title":"Home & Living"},{"id":"beauty","title":"Beauty"}]},{"type":"Footer","label":"Continue","on-click-action":{"name":"navigate","next":{"type":"screen","name":"QUESTI ON_TWO"},"payload":{"product_categories":"${form.product_categories}"}}}]}]}},{"id":"QUESTION_TWO","title":"Question 2 of 2","data":{"product_categories":{"type":"array","items":{"type":"string"},"__example__":[]}},"terminal":true,"success":true,"layout":{"type":"SingleColumnLayout

 ","children":[{"type":"Form","name":"form","children":[{"type":"TextHeading","text":"What's your typical budget?"},{"type":"RadioButtonsGroup","label":"Choose one:","required":true,"name":"budget_range","data-source":[{"id":"under_50","title":"Under $50"},{"id":"50_150","title":"$50 - $150"},{"id":"over_150","title":"Over $150"}]},{"type":"Footer","label":"Submit","on-click-action":{"name":"complete","payload":{"product_categories":"${data.product_categories}","budget_range":"${form .budget_range}"}}}]}]}}]}", "flow_action": "navigate" } ] } ] }

Step 2 — Run the following CLI command to create the template. The –template-definition parameter references the JSON file that you previously created:

aws socialmessaging create-whatsapp-message-template \
--region [AWS_REGION] \
--cli-binary-format raw-in-base64-out \
--id [WABA_ID] \
--template-definition file://anycompany_survey_template.json

Sending the WhatsApp Flow

After the Template and Flow are approved, a message can be sent with the following code.

message_data = {
    "messaging_product": "whatsapp",
    "to": config['destinationPhoneNumber'],
    "type": "template",
    "template": {
        "name": "anycompany_survey",
        "language": {
            "code": "en_US"
        },
        "components": [
            {
                "type": "button",
                "sub_type": "flow",
                "index": "0",
                "parameters": [
                    {
                        "type": "action",
                        "action": {
                            "flow_token": "survey-12345",
                            "flow_action_data": {
                                "screen": "QUESTION_ONE"
                            }
                        }
                    }
                ]
            }
        ]
    }
}

WhatsApp Flow survey example

The Flow will appear with the message body specified and a link to start the survey.

The recipient can provide their answers on each page of the Flow which can be submitted at the end.

After providing inputs, the Flow will show a completed message.

Clean up

To avoid incurring future charges, delete the resources that you created during this walkthrough:

1. In the AWS End User Messaging Social console, disassociate (unlink) the WhatsApp Business Account.
2. Navigate to Message Templates and delete any test templates that you created.
3. Delete any WhatsApp Flows you created in the Flow Playground on the Meta for Developers website.
4. Review your Amazon CloudWatch Logs for any log groups created by the service and delete them if no longer needed.
5. Optionally, if you provisioned a phone number in End User Messaging SMS just for WhatsApp release the phone number in End User Messaging SMS.

For templates created in WhatsApp Manager, you can also delete them directly from the WhatsApp Business Manager interface on the Meta for Developers website.

Conclusion

In this post, you learned how to send various WhatsApp Business message types using AWS End User Messaging Social, including text messages, media messages, template messages, location messages, interactive messages, contact messages, and WhatsApp Flows.

AWS End User Messaging Social provides a managed API that removes the complexity of maintaining your own WhatsApp Business API integration, so you can focus on building engaging customer experiences. The service handles the heavy lifting of managing WhatsApp Business API connections, template approvals, and message delivery, while providing you with a unified, consistent API interface.

Next steps

• Explore advanced template features with dynamic content and media headers
• Implement webhook handlers for incoming messages and delivery receipts
• Set up automated message flows for common customer inquiries using Amazon EventBridge
• Integrate with Amazon Connect for omnichannel customer support experiences

We’d love to hear about your experience! Share your use cases and implementation approaches in the comments.

Additional resources

• AWS End User Messaging Social Documentation
• AWS End User Messaging Social API Reference
• AWS End User Messaging Social User Guide
• WhatsApp Business Platform API Documentation on the Meta for Developers website
• WhatsApp Flows Documentation on the Meta for Developers website
• AWS End User Messaging Social Console

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