Architecting an Integrated Project Management Application: Low-Level Design
Low Level Design

Architecting an Integrated Project Management Application: Low-Level Design

S

Shivam Chauhan

14 days ago

Ever felt lost in the details when trying to build a project management application? I know I have. It's easy to get caught up in features and forget the underlying architecture. Let's break down the low-level design (LLD) of an integrated project management application. We'll look at key components, data models, and implementation details. This is all about getting practical.

Why Low-Level Design Matters

LLD bridges the gap between high-level architecture and actual code. It's where you define classes, methods, and data structures. A solid LLD ensures your application is:

  • Maintainable: Easy to update and fix.
  • Scalable: Able to handle more users and data.
  • Efficient: Performs well under load.
  • Testable: Simple to write unit and integration tests for.

I remember working on a project where we skipped the LLD phase. We rushed into coding and ended up with a tangled mess of dependencies. It was a nightmare to debug and nearly impossible to scale. That experience taught me the value of a well-thought-out LLD.

Key Components of a Project Management Application

Let's outline the core components we'll need:

  1. User Management: Handles user authentication, authorization, and profile management.
  2. Project Management: Manages projects, tasks, and dependencies.
  3. Task Management: Deals with task creation, assignment, and tracking.
  4. Resource Management: Allocates resources (people, equipment) to projects.
  5. Collaboration: Enables communication and file sharing among team members.
  6. Reporting: Generates reports on project progress, resource utilization, and performance.

Data Models

A well-defined data model is crucial. Here's a simplified example:

java
// User
class User {
    Long userId;
    String username;
    String email;
    String password;
    String role; // e.g., Admin, Project Manager, Developer
}

// Project
class Project {
    Long projectId;
    String projectName;
    String description;
    Date startDate;
    Date endDate;
    String status; // e.g., Active, Completed, On Hold
    Long projectManagerId; // Foreign key to User
}

// Task
class Task {
    Long taskId;
    String taskName;
    String description;
    Date startDate;
    Date endDate;
    String status; // e.g., To Do, In Progress, Completed
    Long projectId; // Foreign key to Project
    Long assignedUserId; // Foreign key to User
}

// Resource
class Resource {
    Long resourceId;
    String resourceName;
    String resourceType; // e.g., Person, Equipment
    Double costPerHour;
}

// TaskAssignment
class TaskAssignment {
    Long taskAssignmentId;
    Long taskId;
    Long resourceId;
    Double hoursAllocated;
}

These classes represent the basic entities in our application. We'll need repositories or DAOs (Data Access Objects) to interact with the database.

Core Modules and Classes

Let's dive into some key modules and classes with Java examples:

1. User Management Module

  • UserManager Class:
java
class UserManager {
    public User createUser(String username, String email, String password, String role) {
        // Validate input
        // Hash password
        // Persist user to database
        return new User();
    }

    public User authenticateUser(String username, String password) {
        // Retrieve user from database
        // Verify password
        return new User();
    }

    public void updateUserProfile(User user) {
        // Update user details in database
    }
}
  • AuthenticationService Interface:
java
interface AuthenticationService {
    User authenticate(String username, String password);
}

class BasicAuthenticationService implements AuthenticationService {
    @Override
    public User authenticate(String username, String password) {
        // Basic authentication logic
        return new User();
    }
}

2. Project Management Module

  • ProjectManager Class:
java
class ProjectManager {
    public Project createProject(String projectName, String description, Date startDate, Date endDate, Long projectManagerId) {
        // Validate input
        // Persist project to database
        return new Project();
    }

    public void updateProjectStatus(Project project, String status) {
        // Update project status in database
    }

    public List<Task> getTasksForProject(Long projectId) {
        // Retrieve tasks from database
        return new ArrayList<>();
    }
}
  • ProjectRepository Interface:
java
interface ProjectRepository {
    Project findById(Long projectId);
    List<Project> findAll();
    Project save(Project project);
    void delete(Long projectId);
}

3. Task Management Module

  • TaskManager Class:
java
class TaskManager {
    public Task createTask(String taskName, String description, Date startDate, Date endDate, Long projectId, Long assignedUserId) {
        // Validate input
        // Persist task to database
        return new Task();
    }

    public void updateTaskStatus(Task task, String status) {
        // Update task status in database
    }

    public void assignTaskToUser(Task task, User user) {
        // Assign task to user in database
    }
}
  • TaskService Interface:
java
interface TaskService {
    Task getTaskById(Long taskId);
    List<Task> getAllTasks();
    Task createTask(Task task);
    void updateTask(Task task);
    void deleteTask(Long taskId);
}

4. Resource Management Module

  • ResourceManager Class:
java
class ResourceManager {
    public Resource createResource(String resourceName, String resourceType, Double costPerHour) {
        // Validate input
        // Persist resource to database
        return new Resource();
    }

    public void allocateResourceToTask(Resource resource, Task task, Double hours) {
        // Allocate resource to task in database
    }

    public Double calculateTaskCost(Task task) {
        // Calculate the cost of a task based on allocated resources
        return 0.0;
    }
}

5. Collaboration Module

  • CollaborationService Interface:
java
interface CollaborationService {
    void sendMessage(User sender, User receiver, String message);
    List<String> getMessages(User user1, User user2);
    void shareFile(User user, Project project, String filePath);
    List<String> getFiles(Project project);
}

class BasicCollaborationService implements CollaborationService {
    @Override
    public void sendMessage(User sender, User receiver, String message) {
        // Logic to send message
    }

    @Override
    public List<String> getMessages(User user1, User user2) {
        // Logic to get messages
        return null;
    }

    @Override
    public void shareFile(User user, Project project, String filePath) {
        // Logic to share file
    }

    @Override
    public List<String> getFiles(Project project) {
        // Logic to get files
        return null;
    }
}

6. Reporting Module

  • ReportGenerator Class:
java
class ReportGenerator {
    public String generateProjectReport(Project project) {
        // Generate a report on project progress
        return "";
    }

    public String generateResourceUtilizationReport(Project project) {
        // Generate a report on resource utilization
        return "";
    }

    public String generatePerformanceReport(Project project) {
        // Generate a report on project performance
        return "";
    }
}

UML Diagram

Here’s a simplified UML diagram representing the core components:

Drag: Pan canvas
React Flow

FAQs

Q: How do I handle user authentication?

Use established libraries like Spring Security or JWT (JSON Web Tokens). Avoid rolling your own authentication system unless you're an expert in security.

Q: What database should I use?

Relational databases like PostgreSQL or MySQL are good choices for structured data. NoSQL databases like MongoDB can be useful for flexible schemas.

Q: How do I handle concurrency?

Use appropriate locking mechanisms and transaction management. Consider using optimistic locking to minimize conflicts.

Where Coudo AI Comes In

Want to test your LLD skills? Check out Coudo AI problems. They offer practical coding challenges that help you refine your design skills. For example, you might find problems related to movie ticket booking or expense sharing, which require similar design considerations.

Best Practices

  • SOLID Principles: Apply SOLID principles to create maintainable and extensible code.
  • Design Patterns: Use appropriate design patterns to solve common problems.
  • Code Reviews: Conduct regular code reviews to catch errors and improve code quality.
  • Testing: Write unit and integration tests to ensure code correctness.

Conclusion

Architecting an integrated project management application requires careful planning and attention to detail. By following a structured LLD process, you can build a robust and scalable system.

Ready to put your skills to the test? Check out Coudo AI's LLD learning platform for more challenges and resources. Remember, a solid low-level design is the backbone of any successful application, so take the time to get it right! \n\n

About the Author

S

Shivam Chauhan

Sharing insights about system design and coding practices.