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Relay GraphQL Server

https://github.com/plexey/graphql-relay-server

This project contains an API for a fake book store called Athenaeum. It showcases a GraphQL API compliant with the Relay GraphQL server spec.

#Project Stack:

  • GraphQL API
  • Express API
  • PostgreSQL
  • Docker

#Features:

  • Relay GraphQL API featuring:
    • Global Object Identification
    • Cursor Connections
    • Dataloaders
  • Authentication via salted hashed password
  • Authorization via signed JWT
  • Database data mocking with Faker

#Table of Contents

#Setup

Setting up this project involves the following:

#Install Docker

The data for the GraphQL API in this project is resolved from a PostgreSQL database running as a Docker container. If you don't already have Docker installed, you can download Docker using the link below: https://docs.docker.com/get-docker/

#Pull PostgreSQL Docker Image

With Docker installed, let's pull down the PostgreSQL Docker image with this command: 
docker pull postgres
Now we can use this image to spin up a PostgreSQL Docker container.

#Setup Database

Before we spin up a new postgres Docker container, let's first clone this project and then install its dependencies with: 
npm install
With the project cloned and it's dependencies installed we'll next create a new .env file in the project root with the following contents: 
POSTGRES_USER=root
POSTGRES_PASSWORD=example_password
POSTGRES_DB=athenaeum
HMAC_SECRET_KEY=abcd1234
The project includes a .env-example file which can be used as a reference. The environment variables contained in the .env file will be used to provision a new postgres Docker container among other uses. Now we can proceed with setting up the database - let's run the following command to do this: 
npm run db:setup
This command does three things:
  1. Spins up a postgres database inside a Docker container
  2. Inserts tables into the postgres database
  3. Populates database tables with some mock data
After running the above command, we should have a running database with the following tables:
  • users
  • books
  • authors
  • genres
  • book_authors
  • book_genres
  • book_format
  • genre_type
We can verify this in a number of ways - personally I prefer to jump into a PostgreSQL GUI such as pgAdmin to inspect the database.

#Start Express Server

Now that the postgres database is setup, we can spin up the Express server provided by this project. This can be done via the following command: 
npm run start
This will spin up an Express server exposing three REST endpoints:
  • /register - endpoint to register new user account
  • /login - endpoint to login as particular user
  • /graphql - endpoint to send GraphQL queries to

#Register User

To use the /graphql endpoint we first need to register as a new user and then login as that user. See the register endpoint documentation for more details. Once a new user account has been registered, we can proceed to login as that user.

#Login User

The /login endpoint is used to login with a set of user credentials and responds with a JSON Web Token, or JWT for short. See the login endpoint documentation for more details. Once a JWT has been obtained via the /login endpoint, we can proceed to query the GraphQL API endpoint /graphql.

#GraphQL API

This project ships with GraphiQL allowing you to write and execute queries via a web interface. If the Express server is up, we can head over to http://localhost:4000/graphql to start querying the GraphQL API. To use the GraphiQL interface, we'll need to create a new cookie in the browser called Authorization with the value of the JWT we acquired by logging in.

#Endpoints

#register

The /register endpoint is used to register a new user account. Method: POST Expected HTTP headers:
Content-Type'application/json'
Expected arguments:
FieldTypeRequired
emailstringtrue
firstNamestringtrue
lastNamestringtrue
passwordstringtrue
confirmPasswordstringtrue

#login

The /login endpoint is used to login with a set of user credentials and responds with a JSON Web Token, abbreviated to JWT. Method: POST Expected HTTP headers:
Content-Type'application/json'
Expected Arguments:
FieldTypeRequired
emailstringtrue
passwordstringtrue

#graphql

The /graphql endpoint accepts GraphQL requests. Method: POST HTTP Headers:
Content-Type'application/json'
Authorization'Bearer xxx.xxx.xxx'

Some of the tech I worked with on this project:

RelayExpressDockerPostgreSQLGraphQLDataLoaderJWTTypeScript