Identity Reconciliation

Introduction

This project aims to solve the challenge of identity reconciliation for customers making purchases with different contact information on an e-commerce platform. The platform can identify and track customer identities across multiple purchases, even if different emails and phone numbers are used.

Features

• Identify and consolidate customer contact information.
• Link multiple contacts to a primary contact.
• Ensure a personalized customer experience by tracking loyal customers.

Database Schema

The contact information is stored in a relational database table named Contact:

{
    id Int,
    phoneNumber String?,
    email String?,
    linkedId Int?, // the ID of another Contact linked to this one
    linkPrecedence "secondary" | "primary", // "primary" if it's the first Contact
    createdAt DateTime,
    updatedAt DateTime,
    deletedAt DateTime?
}

Endpoint

/identify

Request

The /identify endpoint receives HTTP POST requests with a JSON body containing either or both of the following fields:

{
    "email": "string",
    "phoneNumber": "number"
}

Response

The endpoint returns an HTTP 200 response with a JSON payload containing the consolidated contact information:

{
    "contact": {
        "primaryContactId": "number",
        "emails": ["string"], // first element being email of primary contact
        "phoneNumbers": ["string"], // first element being phoneNumber of primary contact
        "secondaryContactIds": ["number"] // Array of all Contact IDs that are "secondary"
    }
}

Examples

Request

{
    "email": "mcfly@hillvalley.edu",
    "phoneNumber": "123456"
}

Response

{
    "contact": {
        "primaryContactId": 1,
        "emails": ["lorraine@hillvalley.edu", "mcfly@hillvalley.edu"],
        "phoneNumbers": ["123456"],
        "secondaryContactIds": [23]
    }
}

Usage Scenarios

Scenario 1: No Existing Contacts

If there are no existing contacts matching the incoming request, a new Contact row is created with linkPrecedence="primary".

Scenario 2: Existing Contact with New Information

If an incoming request has either a phone number or email common to an existing contact but contains new information, a new secondary Contact row is created and linked to the primary contact.

Scenario 3: Turning Primary Contacts into Secondary

If a new contact links two existing contacts, one of them will become a secondary contact. The database will update accordingly.

Technology Stack

• Database: My SQL
• Backend Framework: Node.js with TypeScript

Deployment

The application is hosted online, and the endpoint can be accessed at: https://identity-reconciliation-wjcz.onrender.com/identify [POST Request]

How to Run

1. Clone the repository from GitHub.
2. Install dependencies using npm install.
3. Set up your database and configure the connection settings.
4. Run the application using npm start.