acetay/cart-spring-boot-api

Spring Boot Lesson

Quick Start

To run the project:

Step 1: CD to the project root directory cart_api

Step 2: Run ./mvnw spring-boot:run command

Lesson Overview (24 Feb 2023, Fri)

Previously, we have

• Create a spring starter project with web dependency here
• Used several annotations to create RESTful API

@RestController
@RequestMapping
@RequestBody
@ResponseBody
@PathVariable
@Autowired
@Service

In this lesson, we will cover:

1. Configure a custom singleton object using @Bean annotation
2. The use of @Value annotation to inject environmental variable
3. Implementing a logger to capture all API Input

Essentially, there are three common ways to configure and inject Spring Bean/Value.

1. Using @Component or its children - @RestController, @Service, etcs..
2. Using @Value to inject value picked up from application.properties file.
3. Using @Bean on a method that returns a configured object.

Practically, we will create this endpoint:

Path	Verb	Return Status	Remarks
/payment?payable=5.3	POST	200	Payment successful
		400	When payment is below minimum payable sum or negative value.

Lesson Overview (20 Feb 2023, Mon)

1. Generate a Spring Project with the web dependency added
2. Annotations Explanations:
   • @SpringBootApplication
   • @RestController
   • @RequestMapping
   • @RequestBody
   • @RequestResponse

By the end of the class, we would have created:

1. GET /products
2. GET /products/{id}
3. POST /products
4. PUT /products/{id}
5. DELETE /products/{id}

Standard REST API

Path	Verb	Has Request Body	Has Response Body	Purpose
/entities	GET	NO	YES	Get all entities (usually with pagination and sorting query parameters)
/entities/{id}	GET	NO	YES	Get one entity by id
/entities	POST	Yes	YES	Create an entity
/entities/{id}	PUT	YES	YES	Update an entity
/entities/{id}	DELETE	NO	NO	Delete an entity

For more info - Link