nottpty / payment-graphql-springboot

Demo Payment API

Intro

This project for GraphQl + Spring Boot. The project uses graphql to create a simple payment schema to demonstrate the use of GraphQl Query, Mutation functionality.

Requirements

• Java 17
• PostgreSQL
• Basic Knowledge of GraphQl and Spring boot
• Intellij or IDE of your choice
• Postman for testing the API
• Docker

What is GraphQl?

GraphQl is a query language that can be used to develop APIs which uses a different approach than the trditional REST APIs. Unlike traditional REST APIs GraphQl allows the client to specify which data required and thus allowing multiple queries in a single request. This helps to develop light weight manageable APIs.

Official documentation: GraphQL

How to execute

To run the project by docker and execute queries follow below steps:

.\mvnw clean install -DskipTests jib:dockerBuild

• In terminal cd the Root folder of project where we have docker-compose.yml

docker-compose up -d

• the endpoint exposed at : localhost
• postman or any Http client can be used to test the graphql queries
• GraphiQL is a browser-based user interface for interactively exploring the capabilities of, and executing queries against, a GraphQL API.

To stop all containers

docker-compose down

Example of some queries/mutations:

Note all queries and mutations in GraphQl are post Http requests.

Why only Post?

Well, there are few reasons:

• GraphQl itself is transport-agnostic, it's not specific to HTTP. A GraphQl service can execute documents outside the context of network requests.
• There is no body in a GET request, which means the query, variables and operation name all have to be set through query parameters which can easily cause server to return 414 status(URI too long)

Query example

get all payment transaction

 query {
   getAllPayment {
     id,
     finalPrice,
     points,
     datetime
   }
 }

get sales by start date and end date

query {
  getSaleByStartDateTimeToEndDateTime(
    startDateTime:"2023-03-23T00:00:00Z",
    endDateTime:"2023-03-24T00:00:00Z",
    order: ASC
  ) {
    datetime,
    sales,
    points,
  }
}

Mutation example

create new payment

mutation {
  createPayment(input: {
    price: 55.00, 
    priceModifier: 0.95, 
    paymentMethod: CASH, 
    datetime: "2023-03-23T01:00:00Z"
  }) 
  {
    id
    finalPrice
    points
    datetime
  }
}