leenahere/watch-api

⌚️ Watch Online Shop API

Simple API built with nest.js, GraphQL, TypeORM and PostgreSQL for showcasing operations of watch online shop.

The project contains four modules to showcase a simple checkout action:

• watch
• discount
• user
• cart

Considering that the API would be consumed by a "dumb" client, the backend holds the state of a user's cart. So instead of creating an endpoint that calculates a total cost of a list of watches the client can access and update the cart's state through the respective queries/mutations. To obtain the total of a user's cart the following query can be used:

query {
  cart(id: 'cart-id') {
    total
  }
}

To add items to a user's cart and obtain the updated total of the cart, the client can use the following mutation:

mutation {
  addCardItem(id: 'card-id', newItem: 'watch-id') {
    total
  }
}

🏃🏼‍♀️ Run

To run the API a docker-compose is provided. First create a .env file, add the vars from .env.example and source the .env file locally for the PostgreSQL service:

source .env

The run the following command to fire up the API and a PostgreSQL:

docker-compose up

The GraphQL playground can be accessed on http://localhost:3000/graphql.

To seed the db run the seed query in the playground:

query {
  seed
}

This will create all necessary items to test out all endpoints. The seeded data can be found in seed.resolver.ts.

🧪 Tests

For tests the Jest test framework is used. Before running build, tests are automatically run when building the docker image.

Tests can be run locally with the following command:

npm run test

As of now only the cart.service.spec.ts tests are implemented and the endpoint for creating a new cart item considered to contain the vital business logic is tested. Tests for the other services would be written in the same manner.

👷🏼‍♀️ Room for Improvement

There are several things that could be improved here to enhance usability of the API:

• Increase test coverage
• Add authorization and authentication for API
• Add user management
• Refactor watch module to be product module to achieve a more generic data model
• Add error handling for adding undefined products/watches to cart
• Add and endpoint to remove items from the cart
• Refactor cart item data structure to already include quantity in the structure (will remove computational expensive calculations)