LLD for a Comprehensive Food Delivery Support and Helpdesk Module

We're diving deep into the low-level design (LLD) of a support and helpdesk module for a food delivery application. This is your playbook to tackle similar challenges. We'll break down the key components, interactions, and design choices necessary to build a robust and efficient support system.

Why Does This Matter?

Imagine placing an order, waiting eagerly, and then... nothing. No food, no updates, just radio silence. Frustrating, right? A well-designed support module is crucial for handling such situations, ensuring customer satisfaction, and maintaining the food delivery app's reputation.

I remember once when my order was seriously delayed, and the app's support was a lifesaver. They tracked down my order, offered a discount, and kept me updated. That experience highlighted the importance of a responsive and helpful support system.

Key Features to Consider

Before we dive into the LLD, let's outline the core features we need to support:

Ticket Management: Users should be able to raise tickets for issues like delayed orders, incorrect items, payment problems, etc.
Real-time Chat: Integrate a chat interface for instant assistance.
Knowledge Base: A repository of FAQs and help articles to address common queries.
Agent Dashboard: A centralized dashboard for support agents to manage tickets, chats, and access relevant information.
Escalation Mechanism: Ability to escalate tickets to senior agents or supervisors when necessary.
Analytics and Reporting: Track key metrics like resolution time, customer satisfaction, and ticket volume.

Low-Level Design Components

Let's break down the major components of our support module:

Ticket Service

Responsibilities: Handles ticket creation, updates, retrieval, and status transitions.
Key Classes:
- Ticket: Represents a support ticket with attributes like ticket ID, user ID, order ID, issue type, status, creation timestamp, and resolution timestamp.
- TicketRepository: Interface for interacting with the database to persist and retrieve ticket data.
- TicketService: Provides methods for creating, updating, and resolving tickets. It uses the TicketRepository for data access.
Example Code (Java):

java
public class Ticket {
    private String ticketId;
    private String userId;
    private String orderId;
    private String issueType;
    private String status;
    private LocalDateTime createdAt;
    private LocalDateTime resolvedAt;

    // Constructors, getters, and setters
}

public interface TicketRepository {
    Ticket findById(String ticketId);
    void save(Ticket ticket);
    List<Ticket> findByUserId(String userId);
}

public class TicketService {
    private TicketRepository ticketRepository;

    public TicketService(TicketRepository ticketRepository) {
        this.ticketRepository = ticketRepository;
    }

    public Ticket createTicket(String userId, String orderId, String issueType) {
        Ticket ticket = new Ticket();
        ticket.setTicketId(UUID.randomUUID().toString());
        ticket.setUserId(userId);
        ticket.setOrderId(orderId);
        ticket.setIssueType(issueType);
        ticket.setStatus("OPEN");
        ticket.setCreatedAt(LocalDateTime.now());

        ticketRepository.save(ticket);
        return ticket;
    }

    // Other methods for updating and resolving tickets
}

Chat Service

Responsibilities: Manages real-time communication between users and support agents.
Key Classes:
- ChatSession: Represents a chat session between a user and an agent. It includes session ID, user ID, agent ID, start time, end time, and a list of messages.
- Message: Represents a single message within a chat session. It contains the sender ID, message content, timestamp, and message type (text, image, etc.).
- ChatService: Provides methods for starting a chat session, sending messages, and ending a session. It may use technologies like WebSockets or Socket.IO for real-time communication.
Example Code (Conceptual):

java
// Simplified example - Real implementation would involve WebSockets/Socket.IO
public class ChatService {
    public void sendMessage(String sessionId, String senderId, String message) {
        // Logic to route the message to the appropriate chat session participants
    }
}

Knowledge Base Service

Responsibilities: Stores and retrieves FAQs and help articles.
Key Classes:
- Article: Represents a knowledge base article with attributes like article ID, title, content, keywords, and creation/update timestamps.
- ArticleRepository: Interface for interacting with the database to persist and retrieve article data.
- KnowledgeBaseService: Provides methods for creating, updating, searching, and retrieving articles.
Example Code (Java):

java
public class Article {
    private String articleId;
    private String title;
    private String content;
    private List<String> keywords;

    // Constructors, getters, and setters
}

public interface ArticleRepository {
    Article findById(String articleId);
    List<Article> searchByKeywords(List<String> keywords);
}

public class KnowledgeBaseService {
    private ArticleRepository articleRepository;

    public List<Article> searchArticles(String query) {
        // Logic to parse the query and search for relevant articles
        return articleRepository.searchByKeywords(Arrays.asList(query.split(" ")));
    }
}

Agent Dashboard Service
- Responsibilities: Provides a user interface for support agents to manage tickets and chats.
- Key Components: UI elements for displaying ticket lists, chat interfaces, user information, and knowledge base search. This service interacts with the Ticket Service, Chat Service, and Knowledge Base Service to retrieve and display data.
Escalation Service
- Responsibilities: Handles the escalation of tickets based on predefined rules or agent requests.
- Key Classes:
  - EscalationRule: Represents an escalation rule with attributes like issue type, priority level, and escalation target (e.g., senior agent, supervisor).
  - EscalationService: Evaluates escalation rules and routes tickets to the appropriate escalation target.

UML Diagram (Conceptual)

While a detailed UML diagram would be extensive, here's a simplified representation:

Drag: Pan canvas

React Flow

Design Considerations

Scalability: The support module should be able to handle a large volume of tickets and chats, especially during peak hours. Consider using message queues (e.g., Amazon MQ, RabbitMQ) for asynchronous processing of tickets and notifications.
Real-time Communication: Choose a suitable technology for real-time chat, such as WebSockets or Socket.IO. Ensure the chat service can handle concurrent connections efficiently.
Search Functionality: Implement efficient search algorithms for the knowledge base. Consider using a search engine like Elasticsearch or Solr for full-text search capabilities.
Security: Protect sensitive user data and ensure secure communication channels. Implement proper authentication and authorization mechanisms.

Internal Linking Opportunities

Check out Coudo AI's problems on expense-sharing-application-splitwise to give you a solid understanding of real-world application development.

FAQs

Q: How do I handle image uploads in the chat service?
- A: Use a cloud storage service like AWS S3 or Azure Blob Storage to store image files. Send the image URL through the chat service.
Q: How do I implement priority-based ticket routing?
- A: Assign priority levels to tickets based on issue type and user tier. Use the Escalation Service to route high-priority tickets to senior agents.
Q: How can I track customer satisfaction?
- A: Implement a feedback mechanism after ticket resolution. Send a survey to users asking about their support experience.

Wrapping Up

Designing a comprehensive support and helpdesk module requires careful consideration of various factors, including ticket management, real-time communication, and knowledge base integration. By following the LLD principles outlined here, you can build a robust and efficient support system for your food delivery application.

Want to test your LLD skills? Head over to Coudo AI and tackle some real-world design problems. It’s a great way to solidify your understanding and prepare for those LLD interviews! This is how you ensure customer happiness, one solved ticket at a time. \n\n