Server

This project is a .NET 8 backend API that connects to a PostgreSQL database. It provides endpoints for managing categories, questions, and answers, including uploading and streaming video files associated with answers.

Table of Contents

• Server
  • Table of Contents
  • Overview
  • API Endpoints
    • Categories
      • GET /api/categories ✅
      • GET /api/categories/detailed ✅
      • GET /api/categories/{id} ✅
      • POST /api/categories ✅
      • PUT /api/categories/{id} ✅
      • DELETE /api/categories/{id} ✅
    • Questions
      • GET /api/questions??categoryId={Guid}&content={string}&pageNumber={number}&pageSize={number}' ✅
      • GET /api/questions/random?categoryId={Guid} ✅
      • GET /api/questions/{id} ✅
      • POST /api/questions ✅
      • PUT /api/questions/{id} ✅
      • DELETE /api/questions/{id} ✅
    • Answers
      • POST /api/answers ✅
      • GET /api/answers/{id} ✅
      • GET /api/answers/{id}/metadata ✅
      • DELETE /api/answers/{id} ✅
  • Database Entities
    • Categories
    • Questions
    • Answers
  • Getting Started
    • Prerequisites
    • Configuration
    • Running the Application
    • Migration Scripts
  • Contributing
  • License

Overview

The server application provides a RESTful API for:

• Categories: Managing categories for organizing questions.
• Questions: CRUD operations for interview questions.
• Answers: Handling video uploads and streaming for recorded answers.

---

API Endpoints

Categories

GET /api/categories ✅

Retrieves all categories.

• Response:

  • Status: 200 OK

  • Body:

    [
      {
        "id": "uuid",
        "name": "Databases"
      },
      {
        "id": "uuid",
        "name": "Design Patterns"
      }
    ]

GET /api/categories/detailed ✅

Retrieves all categories and the number of its submitted questions.

• Response:

  • Status: 200 OK

  • Body:

    [
      {
        "id": "uuid",
        "name": "Databases",
        "questionsCount": 1
      },
      {
        "id": "uuid",
        "name": "Design Patterns",
        "questionsCount": 1
      }
    ]

GET /api/categories/{id} ✅

Retrieves a specific category.

• Response:

  • Status: 200 OK

  • Body:

    {
      "id": "uuid",
      "name": "Databases"
    }

POST /api/categories ✅

Adds a new category.

• Request:

  • Headers:

    • Content-Type: application/json

  • Body:

    {
      "name": "Category Name"
    }

• Response:

  • Status: 201 Created

  • Body:

    "uuid"

PUT /api/categories/{id} ✅

Updates an existing category.

• Parameters:

  • id (required): UUID of the category to update.

• Request:

  • Headers:

    • Content-Type: application/json

  • Body:

    {
      "name": "Category Name"
    }

• Response:

  • Status: 200 OK

  • Body:

    {
      "id": "uuid",
      "name": "Category Name"
    }

DELETE /api/categories/{id} ✅

Deletes a category and its associated questions/answers.

• Parameters:

  • id (required): UUID of the category to delete.

• Response:

  • Status: 204 No Content

---

Questions

GET /api/questions??categoryId={Guid}&content={string}&pageNumber={number}&pageSize={number}' ✅

Retrieves questions and its answers, optionally filtered by category.

• Parameters:

  • categoryId (optional): Optional category to filter questions by.
  • content (optional): Optional content to filter questions by (case-insensitive).
  • pageNumber: Optional page number for pagination. Defaults to 1.
  • pageSize: Optional page size for pagination. If not provided, all matching questions are returned.

• Response:

  • Status: 200 OK

  • Body:

    [
      {
        "id": "uuid",
        "categoryId": "uuid",
        "content": "Question content",
        "hint": "Optional hint",
        "answersCount": 5
      }
    ]

GET /api/questions/random?categoryId={Guid} ✅

Retrieves a random question, optionally filtered by category.

• Parameters:

  • categoryId (optional): UUID of the category to filter questions.

• Response:

  • Status: 200 OK

  • Body:

    {
      "id": "uuid",
      "categoryId": "uuid",
      "content": "Random question content",
      "hint": "Optional hint"
    }

GET /api/questions/{id} ✅

Gets a specific question and its answers.

• Parameters:

  • id (required): UUID of the question.

• Response:

  • Status: 200 OK

  • Body:

    {
      "question": {
        "id": "uuid",
        "categoryId": "uuid",
        "content": "Question content",
        "hint": "Optional hint"
      },
      "answers": [
        {
          "id": "uuid",
          "questionId": "uuid",
          "videoFileName": "123.webm",
          "createdAt": "Date"
        }
      ]
    }

POST /api/questions ✅

Adds a new question.

• Request:

  • Headers:

    • Content-Type: application/json

  • Body:

    {
      "categoryId": "uuid",
      "content": "New question content",
      "hint": "Optional hint"
    }

• Response:

  • Status: 201 Created

  • Body:

    "uuid"

PUT /api/questions/{id} ✅

Updates an existing question.

• Parameters:

  • id (required): UUID of the question to update.

• Request:

  • Headers:

    • Content-Type: application/json

  • Body:

    {
      "categoryId": "uuid",
      "content": "Updated question content",
      "hint": "Updated hint"
    }

• Response:

  • Status: 200 OK

  • Body:

    {
      "id": "uuid",
      "categoryId": "uuid",
      "content": "Updated question content",
      "hint": "Updated hint"
    }

DELETE /api/questions/{id} ✅

Deletes a question and its associated answers.

• Parameters:

  • id (required): UUID of the question to delete.

• Response:

  • Status: 204 No Content

---

Answers

POST /api/answers ✅

Uploads a new answer video for a question.

• Request:

  • Headers:

    • Content-Type: multipart/form-data

  • Body:

    • questionId (form field): UUID of the question being answered.
    • videoFile (form field): The video file to upload.

• Response:

  • Status: 201 Created

  • Body:

    "uuid"

GET /api/answers/{id} ✅

Streams the video associated with the specific answer ID.

• Parameters:

  • id (required): UUID of the answer.

• Response:

  • Status: 200 OK

  • Headers:

    • Content-Type: video/webm (or appropriate video MIME type)
    • Accept-Ranges: bytes

  • Body:

    • Binary video data.

• Note: This endpoint supports video streaming with byte-range requests.

GET /api/answers/{id}/metadata ✅

Gets an answer and its metadata.

• Parameters:

  • id (required): UUID of the answer.

• Response:

  • Status: 200 OK

  • Body:

    {
      "id": "uuid",
      "questionId": "uuid",
      "videoFileName": "123.webm"
    }

DELETE /api/answers/{id} ✅

Deletes an answer and its associated video file.

• Parameters:

  • id (required): UUID of the answer to delete.

• Response:

  • Status: 204 No Content

---

Database Entities

Categories

• Fields:
  • id: UUID (Primary Key)
  • name: String

Questions

• Fields:
  • id: UUID (Primary Key)
  • categoryId: UUID (Foreign key to Categories)
  • content: Text
  • hint: Text (Nullable)
  • createdAt: Timestamp
  • updatedAt: Timestamp

Answers

• Fields:
  • id: UUID (Primary Key)
  • questionId: UUID (Foreign key to Questions)
  • videoFilename: String
  • createdAt: Timestamp
  • updatedAt: Timestamp

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Getting Started

Prerequisites

• .NET 8 SDK: Ensure you have the .NET 8 SDK installed.
• PostgreSQL: A running PostgreSQL instance.
• Entity Framework Core CLI: For running migrations.

Configuration

1. Connection String

   Update the appsettings.json file with your PostgreSQL connection string and the file path for storing video files:

   {
     "ConnectionStrings": {
       "DefaultConnection": "Host=localhost;Database=YourDatabase;Username=YourUsername;Password=YourPassword"
     },
     "VideoStorage": {
       "FilePath": "/videos/"
     }
   }

2. Environment Variables

   Alternatively, you can use environment variables to set the connection string.

Running the Application

1. Apply Migrations

   Use Entity Framework Core to apply migrations and create the database schema.

   dotnet ef database update

2. Run the Application

   dotnet run

   The API will be accessible at http://localhost:5000 (or the configured port).

Migration Scripts

Examples of how to manage migrations:

• Add a Migration

  dotnet ef migrations add InitialCreate --project Br1InterviewPreparation.Infrastructure --startup-project Br1InterviewPreparation.API

• Update the Database

  dotnet ef database update --project Br1InterviewPreparation.Infrastructure --startup-project Br1InterviewPreparation.API

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Contributing

Contributions are welcome! If you'd like to contribute to this project, please follow these steps:

1. Fork the Repository

   Click the "Fork" button at the top right of the repository page to create a copy of the repository on your account.

2. Create a Feature Branch

   git checkout -b feature/YourFeatureName

3. Commit Your Changes

   git commit -am 'Add some feature'

4. Push to the Branch

   git push origin feature/YourFeatureName

5. Open a Pull Request

   Go to your forked repository and click the "New Pull Request" button.

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License

This project is licensed under the MIT License. See the LICENSE file for details.