Skip to main content

3. WhatsApp Send Message Flow

This section details the end-to-end process for sending a WhatsApp message to a driver via the ViSN platform. The flow leverages Firestore triggers, Cloud Tasks, and API integrations to ensure reliable message dispatch, logging, and tracking.

1. Message Initiation and Firestore Document Creation​

  • V-Customer Action:
    A V-Customer sends a WhatsApp message using the WhatsApp messaging drawer in ViSN.

  • Document Creation:
    When the message is sent, a Firestore document is created at: /leasecompany/{leaseId}/enquiries/{enquiryId}/whatsapp/messages/chatMessages/{messageId}

2. Trigger Function Activation and Task Enqueueing​

Trigger Function Activation​

  • Monitoring:
    A Cloud Function, configured with an onDocumentCreate trigger, watches for new documents at the above path.

  • Validation:
    Upon activation, the function verifies:

  • The document exists and contains valid data.

  • The presence of lease-specific WhatsApp configuration.

  • The message source (ignoring messages originating from drivers).

  • Whether the message has been migrated during reassignments.

Task Enqueueing​

  • Enqueue Task:
    After successful validation, the function enqueues a task into the whatsapp-messages-queue, ensuring reliable delivery.

  • Payload Structure:
    The task contains all essential message details required for processing:

    Core Details:

    • leaseId – Identifier for the lease company.
    • accountId – Identifier for the supplier group.
    • serviceUnitId – Identifier for the service unit.
    • enquiryId – Enquiry linked to the WhatsApp message.
    • messageDocId – Firestore document ID for reference.

    Message Metadata:

    • driverMobileNumber – Recipient’s phone number.
    • message – Content of the WhatsApp message.
    • type – Message type (e.g., text, template).
    • leaseWhatsappDetails – Configuration details specific to the lease.
    • createdBy – User initiating the message.

    Optional Data:

    • payload – Additional key-value data related to the message.
    • templateType – Specifies the WhatsApp template type, if applicable.
    • ETA – Estimated time of arrival, defaults to 0 if not provided.

3. Queue Service Processing and API Integration​

Task Processing​

  • Endpoint Execution:
    The /whatsapp/sendMessage endpoint in the queue-services picks up the task.

  • WhatsApp API Call:
    The endpoint makes an API call to WhatsApp using the mapped API token and phone number ID. Throughout this process, relevant logs are generated to aid in monitoring and debugging.

Handling API Response​

  • API Response:
    • On success, WhatsApp returns a whatsappMessageId.
    • On failure, the system logs the error and updates the message status as FAILED.

4. Document and Ancillary Database Updates​

Updating the Message Firestore Document​

  • Document Update:
    The original Firestore document is updated with the received whatsappMessageId. /leasecompany/{leaseId}/enquiries/{enquiryId}/whatsapp/messages/chatMessages/{messageId}

  • Performance Tracking: The system increments the numberOfWhatsappMessagesSent entry in the user's performance metrics.

Updating the Ancillary Database​

  • Tracking Conversation:
    A new document is created in the ancillary database at: /whatsapp/{driverPhoneNumber}/enquiryMessages/{enquiryId}

  • Storing Message IDs:
    In this document, the whatsappMessageId is added to an array (arrayOfWhatsappMessageIds) along with other relevant details.

Status: Draft (Pending Review)
Category: Protected
Authored By: Sohan on March 04, 2025