Requirements

Let's dive into designing a community-based discussion platform. Think Reddit, Stack Overflow, or even a simpler forum. The core idea is to allow users to create communities (or forums, boards), post content (threads, questions, answers), and interact with each other through comments, votes, and potentially direct messages. This isn't about building a massively scalable system; it's about creating a well-structured, extensible, and maintainable codebase, focusing on the core domain model. We need to carefully consider how different types of content are handled, how users interact with each other and the content, and how moderation can be implemented. # Requirements ## Functional Requirements 1. **User Management:** * User Registration: Allow users to create accounts with a unique username, password, and email address. * User Login/Logout: Implement secure authentication. * User Profile: Allow users to create and edit their profiles (e.g., bio, avatar). * User Roles: Implement different user roles (e.g., regular user, moderator, administrator), each with different permissions. 2. **Community Management:** * Community Creation: Allow users (with sufficient permissions) to create new communities with a unique name, description, and set of rules. * Community Listing: Allow users to browse existing communities. * Community Joining/Leaving: Allow users to join and leave communities. * Community Settings: Allow moderators to configure community settings (e.g., post approval, banned words). 3. **Content Management:** * Post Creation: Allow users to create posts (threads, questions) within a community. Posts should have a title, content, and potentially tags. * Post Editing/Deletion: Allow users to edit or delete their own posts (within a time limit) and moderators to delete posts. * Comment Creation: Allow users to comment on posts. * Comment Editing/Deletion: Allow users to edit or delete their own comments (within a time limit) and moderators to delete comments. * Content Formatting: Support basic content formatting (e.g., Markdown). 4. **Interaction:** * Voting: Allow users to upvote or downvote posts and comments. * Search: Allow users to search for posts and communities based on keywords. * Notifications: Notify users of relevant events (e.g., new comments on their posts, mentions). * Reporting: Allow users to report posts and comments for moderation. * Direct Messaging (Optional): Allow users to send private messages to each other. 5. **Moderation:** * Post/Comment Removal: Allow moderators to remove posts and comments that violate community rules. * User Banning: Allow moderators to ban users from the community. * Reporting System: Provide moderators with a system for reviewing reported content. ## Non-Functional Requirements 1. **Modularity:** The system should be designed in a modular way, making it easy to add new features or modify existing ones without affecting other parts of the system. 2. **Extensibility:** The system should be extensible, allowing for the addition of new types of content, interaction mechanisms, and moderation tools. For example, how easily could you add support for images or videos in posts? 3. **Testability:** The code should be written in a way that makes it easy to test. This includes using dependency injection, interfaces, and well-defined classes. 4. **Readability:** The code should be easy to read and understand, with clear naming conventions and comments. 5. **Maintainability:** The code should be easy to maintain and debug. 6. **Thread Safety:** Consider how concurrent access to shared resources (e.g., data structures storing posts, users) will be handled. Focus on scenarios like multiple users upvoting the same post simultaneously. Think about using appropriate synchronization mechanisms (locks, concurrent data structures) to prevent race conditions and data corruption. 7. **Security:** Secure the application against common web vulnerabilities (e.g., XSS, SQL injection). This is a general concern; focus on how this affects your data models and access control. ## Core Entities 1. **User:** Represents a user of the platform. Attributes include username, password (hashed), email, profile information, roles, and status (active/banned). 2. **Community:** Represents a community or forum. Attributes include name, description, rules, moderators, and members. 3. **Post:** Represents a post (thread, question). Attributes include title, content, author, community, creation date, modification date, and votes. Consider different `PostType` (Question, Discussion, Announcement). 4. **Comment:** Represents a comment on a post. Attributes include content, author, post, creation date, modification date, and votes. 5. **Vote:** Represents a user's vote on a post or comment. Attributes include voter, voteable item (post or comment), and vote value (upvote or downvote). The `Vote` should be immutable. 6. **Report:** Represents a report of a post or comment. Attributes include reporter, reportable item (post or comment), and reason. 7. **Role:** Represents a user role within a community. Attributes include name (e.g., "moderator", "administrator") and permissions. 8. **ContentFormatter:** Interface for formatting content (e.g., MarkdownFormatter).

Design Community based discussion platform.

Requirements

Interview Simulation

Functional Requirements

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Non-Functional Requirements

Core Entity Identification

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