Polls-Node is an application for creating and voting on polls in real-time, using Fastify, Node.js, Redis, TypeScript, Docker, PostgreSQL, and WebSockets. This documentation describes the components, functionalities, and how to set up and use the application.

• Fastify: Web framework for building efficient APIs.
• Node.js: Execution environment for JavaScript.
• Redis: In-memory database for caching and storing user information.
• TypeScript: Typed superset of JavaScript.
• Docker: Platform for developing, shipping, and running applications in containers.
• PostgreSQL: Relational database management system.
• Prisma: ORM (Object-Relational Mapping) for interacting with the database.
• WebSocket: Bidirectional real-time communication protocol.

• Node.js and npm installed
• Docker and Docker Compose installed

1. Clone the repository:

   git clone https://github.com/yan-pi/polls-node.git

2. Install the dependencies:

   cd polls-node
   pnpm install

3. Configure the environment variables:

   Create a .env file in the project root with the following variables:

   DATABASE_URL="postgresql://<user>:<password>@localhost:5432/polls?schema=public"

   Note: Replace <username> and <password> with your PostgreSQL credentials.

4. Start the services with Docker Compose:

   docker-compose up -d

5. Running migrations

   npx prisma migrate dev

   This will run all migrations creating the tables and other configs inside the database.

polls-node/
|-- src/
|   |-- http/
|   |   |-- poll.ts
|   |   |-- routes/
|   |   |    |-- create-poll.ts
|   |   |    |-- get-poll.ts
|   |   |    |-- vote-on-poll.ts
|   |-- ws/
|   |   |-- poll-results.ts
|   |-- index.ts
|-- .env
|-- docker-compose.yml
|-- tsconfig.json

• Endpoint: POST /poll
• Description: Creates a new poll in the PostgreSQL database.

{
  "question": "What is your favorite animal?",
  "options": ["Dog", "Cat", "Fish"]
}

• Endpoint: GET /polls/:pollId
• Description: Retrieves the details of a specific poll.

• Endpoint: POST /polls/:pollId/vote
• Description: Records the user's vote on a poll and updates the results in real-time via WebSocket.

{
  "option": "Dog"
}

• Endpoint: WS /polls/:pollId/results
• Functionality: Real-time update of poll results.
• Implementation: Utilizes WebSocket to send updated results to clients in real-time.

User login is stored in the Redis cache for authentication and authorization.

We use Prisma as the ORM for interacting with PostgreSQL. The database configuration is in the prisma/schema.prisma file.

After setting up the environment, run the following command to start the server:

pnpm start

The server will be running on port 3333.

Polls-Node is a robust application for creating and voting on polls in real-time, using modern and efficient technologies. With a well-defined and documented architecture, it is easy to understand and extend its functionalities.