LUDEX INTERNSHIP TEST

Getting Started

Prerequisites

Ensure you have the following installed:

• Node.js
• Docker
• Git
• (Recommended) VS Code
  • If you install VS Code, it is recommended to also install the following extensions:
    • ESLint (for linting and code formatting)
    • GraphQL (for syntax highlighting and validation)
    • Prisma (for schema editing and database insights)

Setting Up Your Repository

This project is provided as a GitHub template. To begin, follow these steps:

1. Navigate to the template repository on GitHub.
2. Click the "Use this template" button to create a new repository under your own GitHub account.
3. Clone your newly created repository to your local machine.
4. Ensure that your repository is public, or if you choose to keep it private, grant access to the GitHub user mccjul.
5. Once you have completed the test, provide the link to your repository in your submission.

Running the Project

Launch the Database

First, ensure that you have Docker Desktop installed and running. To verify that Docker is installed and accessible from your terminal, run:

docker --version

If Docker is installed, navigate to the project directory and start the database container by running:

docker compose up -d

This will launch a PostgreSQL database inside a Docker container, which will be used in later steps.

Run Migrations

With the database running, install the project dependencies by executing:

npm install

Once all dependencies are installed, apply database migrations to ensure the schema is correctly set up:

npm run prisma:migrate

Run the Application

Now that everything is set up, you can start the application. To run it in watch mode (which automatically restarts the app on file changes), use the following command:

npm run dev:watch

This command also performs two additional tasks before starting the app:

1. Generates TypeScript types from the Prisma schema.
2. Generates GraphQL types in typeDefinitions.

These generated types will help improve your development experience, especially if you have ESLint enabled in your IDE.

Testing Using GraphQL Playground

Once the application is running, open your browser and navigate to:

http://localhost:4000/graphql

This will open the GraphQL Playground, a UI where you can execute GraphQL queries and mutations.

To run a query, use the following example:

query {
  hello
}

To run a mutation, use:

mutation {
  createSomething(input: { name: "Bob" }) {
    id
    name
  }
}

The response from the backend will appear on the right-hand side of the UI.

The Test

Your task is to implement a CRUD (Create, Read, Update, Delete) Todo backend using GraphQL. The backend should support the following functionalities:

• Create todos
• Mark todos as complete or incomplete
• Update the title of a todo
• Retrieve all todos
• Retrieve all incomplete todos
• Retrieve all completed todos
• Retrieve a single todo by ID
• Delete todos

Technical Requirements

To successfully complete this test, ensure that your implementation meets the following requirements:

• Use TypeScript: Your project should be fully typed, and TypeScript configurations should be properly set up.
• Use Prisma as ORM: The database interactions should be handled using Prisma.
• GraphQL API Implementation: The API should be implemented using GraphQL with appropriate queries and mutations.
• Follow Best Practices: Code should be well-structured, modular, and follow standard best practices (e.g. error handling, and meaningful variable names).
• Database Schema: The Todo entity should have at least the following fields:
  • id (UUID)
  • title (string)
  • completed (boolean)
  • createdAt (timestamp)
  • updatedAt (timestamp)
• Environment Variables: Use an .env file to configure database connections securely.
• Linting & Formatting: Ensure that your code is properly formatted using ESLint and Prettier.
• Validations & Error Handling:
  • Validate user inputs before processing mutations.
  • Handle potential errors, such as trying to update a non-existent todo.
• Version Control: Use Git for version control with clear commit messages.

Bonus Features (Optional)

These additional features are not required but will help your submission stand out:

• Pagination: Implement pagination for retrieving todos.
• Filtering & Sorting: Allow filtering by completed status and sorting by createdAt.
• (MEDIUM-HARD) Due Date: Add a dueDate field to todos. Implement filtering for overdue/upcoming tasks and sort todos by time.
• (HARD) Testing: Write unit and integration tests using Mocha to ensure the API functions correctly.

Relevant Documentation

• Prisma Documentation
• TypeScript Handbook
• GraphQL Guide