fhnw-int / sprint-boot-controller-start

Exercise Instructions

Pre-requisites

• Import this repository into your own GitHub workspace
• Open the project in Codespaces, this will take a few minutes
• Once opened, go to Java Projects and Import Projects

Exercise 1

Understand Controllers and Endpoints

• Refer to WelcomeController.java and the GET mapping in this class. Note the class level annotation @RestController.
• Run the application and access the endpoint on the browser by appending /welcome to the URL. The welcome message should appear.
• Change the endpoint such that the welcome string is displayed as soon as the application starts, i.e., without appending /welcome.
• Same functionality can be achieved by changing the startup class (PizzaApplication) into a Controller class:
  • Add the annotation @RestController at the class level
  • Add a GET mapping to display a welcome message as follows:

          @GetMapping(value="/")
      	public String getWelcomeString() {
          return "Pizza Takeaway Service, welcome!";
      	}

Create new Controller and Endpoints

Let's add the endpoints for CRUD operations on the Pizza entity. Please refer to the exercise on defining API endpoints for a pizzeria.

• Refer to PizzaController.java
• Add an appropriate annotation to make it a Controller class
• Add a unique path "menu" to access all requests to the PizzaController

    @RequestMapping(path="/menu")

• Add the following endpoint to the PizzaController:

  • GET /pizzas
  • Write a method to create a list of pizzas
  • Use the given Pizza data object to access dummy data through the Controller
  • Add GetMapping to the method – define path “/pizzas” and the data format “application/json”
  • Use the ResponseEntity object to return successful and error response

      //get list of pizzas
      @GetMapping(path="/pizzas", produces = "application/json")
      public ResponseEntity getPizzaList() {
          List<Pizza> pizzaList = new ArrayList();
  
          Pizza pizza1 = new Pizza();
          pizza1.setId(1);
          pizza1.setPizzaName("Margherita");
          pizza1.setPizzaToppings("Mozzarella, Tomato Sauce, Basil");
  
          Pizza pizza2 = new Pizza();
          pizza2.setId(2);
          pizza2.setPizzaName("Quattro Stagioni");
          pizza2.setPizzaToppings("Mozzarella, Tomato Sauce, Ham, Mushrooms, Artichokes, Olives");
  
          pizzaList.add(pizza1);
          pizzaList.add(pizza2);
  
          if(pizzaList.isEmpty())
              return ResponseEntity.notFound().build();
          return ResponseEntity.ok(pizzaList);
      }

  • Start the application and test the endpoint by appending /pizzas to the URL. Test directly in the browser or using Postman.

• Similar to the above approach, create the following endpoints:

1. GET /pizzas/{id}

   • Write a new method with input as id of the pizza, annotate it using @PathVariable.
   • Add the annotation @GetMapping to the method.– Define path “/pizzas/{id}” and the data format “application/json”.
   • Use the ResponseEntity object to return successful and error response.
   • Test using the browser or Postman.

   @GetMapping(path="/pizzas/{id}", produces = "application/json")
   public ResponseEntity getPizza(@PathVariable Long id) {
       Pizza pizza1 = new Pizza();
       pizza1.setId(1);
       pizza1.setPizzaName("Margherita");
       pizza1.setPizzaToppings("Mozzarella, Tomato Sauce, Basil");
   
       if (id == 1) {
           return ResponseEntity.ok(pizza1);
       }
       return ResponseEntity.notFound().build();
   }

2. POST /pizzas

   • Write a new method that has Pizza object as an input, annotate it using @RequestBody.
   • Add the annotation @PostMapping to the method – define path “/pizzas”, data format that is consumed and the data format that is produced.
   • Use the ResponseEntity object to return successful response.
   • Test using Postman.

   @PostMapping(path="/pizzas", consumes="application/json", produces = "application/json")
   public ResponseEntity addPizza(@RequestBody Pizza pizza) {
       //TODO: process POST request
   
       return ResponseEntity.status(HttpStatus.CREATED).build();
   }

3. PUT /pizzas/{id}

   • Write a new method that has the pizza id and the Pizza object as inputs, annotate using @PathVariable and @RequestBody respectively.
   • Add the annotation @PutMapping to the method - define path "/pizzas/{id}", data format that is consumed and the data format that is produced.
   • Use the ResponseEntity object to return successful response
   • Test using Postman.

   @PutMapping(path="/pizzas/{id}", consumes="application/json", produces = "application/json")
   public ResponseEntity updatePizza(@PathVariable Long id, @RequestBody Pizza pizza) {
       //TODO: process PUT request
       
       return ResponseEntity.ok(pizza);
   }

4. DELETE /pizzas/{id}

   • Write a new method that has the pizza id as an input, annotate it using @PathVariable.
   • Add the annotation @DeleteMapping to the method - define path "/pizzas/{id}".
   • Use the ResponseEntity object to return successful response.
   • Test using Postman.

   @DeleteMapping(path="/pizzas/{id}")
   public ResponseEntity deletePizza(@PathVariable Long id) {
       //TODO: process DELETE request
       
       return ResponseEntity.noContent().build();
   }

Exercise 2

Follow similar steps to create end points for (pizza) orders.