Customer Management

Overview

The Customer Management module provides comprehensive customer relationship management capabilities for the Bee O'clock platform. This module handles customer data, relationship tracking, and integration with orders and payments systems.

Module Structure

customer-management/
├── api.md                 # REST API endpoints and operations
├── interface.md           # TypeScript interfaces and contracts
├── usecase.md            # Business use cases and application logic
├── db_schema.md          # Database schema and persistence layer
└── README.md             # This overview document

Key Features

Customer Lifecycle Management

• Customer Creation: Create customer records with validation

• Profile Management: Update customer information and preferences

• Relationship Tracking: Track customer interactions and history

• State Management: Soft delete with complete audit trail

Order Integration

• Attendee Processing: Convert order attendees to customer records

• Customer Matching: Smart matching by email and phone

• First-Time Detection: Identify new customer visits

• History Tracking: Maintain comprehensive order history

Payment Integration

• Payer Management: Link customers to payment records

• Billing Information: Manage customer billing preferences

• Payment History: Track customer payment patterns

• Invoice Generation: Customer billing and invoicing

Search and Discovery

• Advanced Search: Multi-field customer search capabilities

• Filtering: Filter by customer type, status, and attributes

• Pagination: Efficient handling of large customer datasets

• Sorting: Flexible sorting by various criteria

Technical Architecture

Design Patterns

• CQRS: Command Query Responsibility Segregation

• Domain-Driven Design: Rich domain models with business logic

• Repository Pattern: Data access abstraction

• Event-Driven: Asynchronous event publishing

• Multi-Tenant: Business-level data isolation

Technology Stack

• Framework: NestJS with TypeScript

• Database: MongoDB with Mongoose ODM

• Caching: Redis for performance optimization

• Messaging: RabbitMQ for event processing

• Validation: Domain-level and schema validation

API Overview

The Customer Management API provides the following main endpoints:

• GET /customers: List and search customers with pagination

• GET /customers/:id: Retrieve specific customer details

• POST /customers: Create new customer records

• PUT /customers/:id: Update existing customer information

• DELETE /customers/:id: Soft delete customer records

All endpoints support:

• Permission Validation: Role-based access control

• Tenant Isolation: Multi-tenant data separation

• Input Validation: Comprehensive data validation

• Error Handling: Consistent error responses

Data Model

Customer Entity

interface ICustomer {
  _id?: string;
  firstName?: string;
  lastName?: string;
  phone?: string;
  email?: string;
  note?: string;
  customerType?: CustomerTypeEnum;
  stateHistory?: StateHistory[];
  createdAt?: string;
  updatedAt?: string;
}

Customer Types

• Regular: Fully registered customers with complete information

• Unregistered: Customers with basic contact information

• New: First-time customers being onboarded

• Anonymous: Minimal information customers for privacy

Validation Rules

• Mandatory Fields: At least one of firstName, lastName, email, or phone required

• Email Format: Valid email format when provided

• Phone Format: Valid phone number with automatic normalization

• Business Rules: Custom validation based on customer type

Business Rules

Customer Creation

1. Identity Validation: Ensure unique customer identification

2. Contact Information: Validate email and phone formats

3. Business Context: Associate with appropriate business tenant

4. Default Values: Apply default customer type and state

Customer Updates

1. Partial Updates: Support updating individual fields

2. Validation: Maintain data integrity on updates

3. History Tracking: Record all changes for audit trail

4. Cache Invalidation: Update cached customer data

Customer Deletion

1. Soft Delete: Preserve data for historical purposes

2. Dependency Validation: Check for active orders or payments

3. State Management: Update customer state history

4. Related Data: Handle references in orders and payments

Integration Points

Order Management

• Attendee Processing: Convert order participants to customers

• Customer Snapshots: Preserve customer data in order records

• First-Time Tracking: Mark new customer interactions

• Service History: Track customer service participation

Payment Processing

• Payer Information: Link payments to customer records

• Billing History: Maintain customer payment records

• Payment Methods: Store customer payment preferences

• Invoice Management: Generate customer invoices

Notification System

• Email Communications: Send order confirmations and updates

• SMS Notifications: Send appointment reminders via phone

• Push Notifications: Mobile app notifications

• Marketing Campaigns: Customer segmentation for targeted messaging

Security and Compliance

Data Protection

• PII Handling: Secure processing of personal information

• Encryption: Protect sensitive customer data at rest and in transit

• Access Control: Role-based permissions for customer operations

• Audit Logging: Complete audit trail of data access and changes

Privacy Compliance

• GDPR Support: Data portability and right to erasure

• Consent Management: Track customer consent preferences

• Data Retention: Automated data lifecycle management

• Anonymization: Remove personal data while preserving analytics

Security Measures

• Input Validation: Sanitize all customer inputs

• Rate Limiting: Prevent abuse of customer APIs

• Authentication: Secure access to customer operations

• Monitoring: Real-time security threat detection

Performance Considerations

Database Optimization

• Indexing Strategy: Optimized indexes for common query patterns

• Query Performance: Efficient customer search and retrieval

• Connection Pooling: Optimal database connection management

• Caching: Redis caching for frequently accessed data

Scalability

• Pagination: Handle large customer datasets efficiently

• Search Optimization: Fast text search across customer fields

• Load Balancing: Distribute customer operations across instances

• Monitoring: Performance metrics and alerting

Development Guidelines

Code Organization

• Use Cases: Business logic in application layer

• Domain Models: Rich entities with validation

• DTOs: Data transfer objects for API contracts

• Repositories: Data access abstraction layer

Testing Strategy

• Unit Tests: Test individual components and business logic

• Integration Tests: Test complete customer workflows

• API Tests: Validate REST endpoint behavior

• Performance Tests: Ensure scalability requirements

Error Handling

• Validation Errors: Clear error messages for validation failures

• Business Logic Errors: Meaningful business rule violation messages

• System Errors: Graceful handling of infrastructure failures

• Logging: Comprehensive error logging and monitoring

Future Enhancements

Planned Features

• Customer Segmentation: Advanced customer categorization

• Preference Management: Detailed customer preferences and settings

• Communication History: Complete interaction timeline

• Loyalty Programs: Customer rewards and loyalty tracking

• Analytics: Customer behavior analysis and insights

Technical Improvements

• Event Sourcing: Complete audit trail with event streams

• Read Replicas: Optimize read performance for customer queries

• Microservice Architecture: Split into focused microservices

• Machine Learning: Customer behavior prediction and insights

Related Documentation

• API Documentation: Detailed REST API reference

• Interface Documentation: TypeScript contracts and types

• Use Case Documentation: Business logic and workflows

• Database Schema: Data persistence and schema design

Getting Started

Prerequisites

• Node.js 18+ and npm/yarn

• MongoDB 5.0+

• Redis 6.0+

• Valid environment configuration

Development Setup

1. Install Dependencies: npm install

2. Database Setup: Configure MongoDB connection

3. Environment: Set up development environment variables

4. Run Tests: npm run test to verify setup

5. Start Development: npm run start:dev

API Testing

Use the provided Postman collection or Swagger UI to test customer management endpoints:

• Swagger UI: /api/docs when running locally

• Health Check: /health endpoint for service status

---

For detailed implementation information, refer to the specific documentation files for each component of the Customer Management module.