{"id":828,"date":"2020-03-30T04:00:00","date_gmt":"2020-03-30T04:00:00","guid":{"rendered":"http:\/\/bullyrooks.com\/index.php\/2020\/03\/30\/simple-spring-boot-service-to-kubernetes-application-step-4-dba10da3d834\/"},"modified":"2021-02-04T01:45:05","modified_gmt":"2021-02-04T01:45:05","slug":"simple-spring-boot-service-to-kubernetes-application-step-4-dba10da3d834","status":"publish","type":"post","link":"https:\/\/bullyrooks.com\/index.php\/2020\/03\/30\/simple-spring-boot-service-to-kubernetes-application-step-4-dba10da3d834\/","title":{"rendered":"Create a REST Controller"},"content":{"rendered":"\n

In this article we\u2019re going to take the service layer we created in the last step and add a REST interface to it. We\u2019re going to follow the hexagonal design principles we previously discussed and add a functional <\/em>or component <\/em>test and explain how those test work and why they\u2019re important.<\/p>\n\n\n\n

Create the Controller and DTO<\/h3>\n\n\n\n

Create the DTO<\/h4>\n\n\n\n

Create a package called com.brianrook.medium.customer.controller.dto<\/code>. Create a class called CustomerDTO <\/code>and add this content:<\/p>\n\n\n\n

package com.brianrook.medium.customer.controller.dto;\n\nimport lombok.AllArgsConstructor;\nimport lombok.Builder;\nimport lombok.Data;\nimport lombok.NoArgsConstructor;\n\n@Data\n@Builder\n@NoArgsConstructor\n@AllArgsConstructor\npublic class CustomerDTO {\n    private Long customerId;\n    @NotBlank\n    @Size(min = 0, max = 100)\n    private String firstName;\n    @NotBlank\n    @Size(min = 0, max = 100)\n    private String lastName;\n    @Pattern(regexp=\"\\\\(\\\\d{3}\\\\)\\\\d{3}-\\\\d{4}\", message = \"Phone number must match the pattern (###)###-####\")\n    @Size(max = 20)\n    private String phoneNumber;\n    @Email\n    @Size(max = 150)\n    private String email;\n}<\/code><\/pre>\n\n\n\n
You can see here that we\u2019ve added javax validation annotations to the DTO. This will signal to spring to trap and return 400 on invalid data.<\/p><\/blockquote>\n\n\n\n
Service Configuration<\/h4>\n\n\n\n
We also need to add some configuration. In src\/main\/resources<\/code> create an application.yaml<\/code> (if it doesn\u2019t exist. Delete any application.properties or bootstrap.properties)<\/p>\n\n\n\n
server:\n  port: 10000\nspring:\n  application:\n    name: customer\n  jackson:\n    deserialization:\n      FAIL_ON_UNKNOWN_PROPERTIES: false<\/code><\/pre>\n\n\n\n
Here we\u2019re going to tell spring to start up on port 10000 refer to this service as customer and also setup the jackson deserializer to ignore any fields that are either not sent or don\u2019t map to fields in our DTO.<\/p><\/blockquote>\n\n\n\n
Create the Controller<\/h4>\n\n\n\n
Create a class called CustomerController <\/code>in com.brianrook.medium.customer.controller<\/code>. Add this content:<\/p>\n\n\n\n
package com.brianrook.medium.customer.controller;\n\nimport com.brianrook.medium.customer.controller.dto.CustomerDTO;\nimport com.brianrook.medium.customer.service.CustomerService;\nimport com.brianrook.medium.customer.service.model.Customer;\nimport lombok.extern.slf4j.Slf4j;\nimport org.springframework.beans.factory.annotation.Autowired;\nimport org.springframework.http.HttpStatus;\nimport org.springframework.http.MediaType;\nimport org.springframework.http.ResponseEntity;\nimport org.springframework.stereotype.Controller;\nimport org.springframework.web.bind.annotation.PostMapping;\nimport org.springframework.web.bind.annotation.RequestBody;\nimport org.springframework.web.bind.annotation.RequestMapping;\n\nimport java.net.URISyntaxException;\n\n@Controller\n@RequestMapping(value = \"\/customer\")\n@Slf4j\npublic class CustomerController {\n    @Autowired\n    private CustomerService customerService;\n\n    @PostMapping(value = \"\/\",\n            consumes = MediaType.APPLICATION_JSON_VALUE<\/em>,\n            produces = MediaType.APPLICATION_JSON_VALUE<\/em>)\n    public ResponseEntity<CustomerDTO> saveCustomer(\n            @RequestBody @Valid CustomerDTO customerDTO) throws URISyntaxException {\n        Customer customer = CustomerDTOMapper.INSTANCE.customerDTOToCustomer(customerDTO);\n\n        Customer savedCustomer = customerService.saveCustomer(customer);\n\n        CustomerDTO savedCustomerDTO = CustomerDTOMapper.INSTANCE.customerToCustomerDTO(savedCustomer);\n        return new ResponseEntity<CustomerDTO>(savedCustomerDTO, HttpStatus.CREATED<\/em>);\n    }\n}<\/code><\/pre>\n\n\n\n
Create DTO Mapper<\/h4>\n\n\n\n
This isn\u2019t going to compile yet, because we need to create a mapper for the DTO to the model object. Lets create a new package in com.brianrook.medium.customer.controller.mapper<\/code> and add an interface called CustomerDTOMapper<\/code> into that package with this content:<\/p>\n\n\n\n
package com.brianrook.medium.customer.controller.mapper;\n\nimport com.brianrook.medium.customer.controller.dto.CustomerDTO;\nimport com.brianrook.medium.customer.service.model.Customer;\nimport org.mapstruct.Mapper;\nimport org.mapstruct.factory.Mappers;\n\n@Mapper\npublic interface CustomerDTOMapper {\n    CustomerDTOMapper INSTANCE <\/em>= Mappers.getMapper<\/em>(CustomerDTOMapper.class);\n\n    CustomerDTO customerToCustomerDTO(Customer customer);\n\n    Customer customerDTOToCustomer(CustomerDTO customerEntity);\n}<\/code><\/pre>\n\n\n\n
Import that class into the controller and make sure it compiles.<\/p>\n\n\n\n
Give it a Floor Run<\/h4>\n\n\n\n
Lets start the application and test it with postman. Right click on MediumCustomerApplication, choose Run \u2018MediumCustomer\u2026main()<\/code> and confirm that you can see the application startup succesfully:<\/p>\n\n\n\n
2020-03-28 13:28:28.773  INFO [customer,,,] 20504 --- [  restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 10000 (http) with context path ''\n2020-03-28 13:28:29.081  INFO [customer,,,] 20504 --- [  restartedMain] c.b.m.c.MediumCustomerApplication        : Started MediumCustomerApplication in 9.781 seconds (JVM running for 10.525)<\/code><\/pre>\n\n\n\n
You can use postman to make a post. Here\u2019s the request:<\/p>\n\n\n\n
POST \/customer\/ HTTP\/1.1\nHost: localhost:10000\nContent-Type: application\/json<\/code><\/pre>\n\n\n\n
{\n \"firstName\": \"Brian\",\n \"lastName\":  \"Rook\",\n \"phoneNumber\": \"(303)555-1212\",\n \"email\": \"testuser@test.com<\/a>\"\n}<\/code><\/pre>\n\n\n\n
which should respond with:<\/p>\n\n\n\n
201 Created\n{\n\"customerId\": 1,\n\"firstName\": \"Brian\",\n\"lastName\": \"Rook\",\n\"phoneNumber\": \"(303)555-1212\",\n\"email\": \"testuser@test.com\"\n}<\/code><\/pre>\n\n\n\n
Write a Functional Test<\/h3>\n\n\n\n
In the test directory create a new java package for com.brianrook.medium.customer.controller<\/code>. In that package create a class called CustomerControllerTest<\/code>. Add this content:<\/p>\n\n\n\n
@Autowired\nprivate OrganizerDAO organizerDAO;\n@LocalServerPort\nint randomServerPort;\n\n\nString organizerPath = \"\/organizer\/\";\n\n@BeforeEach\npublic void setUp(){\n    organizerDAO.deleteAll();\n}\n\n@Test\npublic void testAddCustomerSuccess() throws URISyntaxException\n{\n    RestTemplate restTemplate = new RestTemplate();\n    String baseUrl = \"http:\/\/localhost:\"+randomServerPort+organizerPath;\n    URI uri = new URI(baseUrl);\n    OrganizerDTO organizerDTO = OrganizerDTO.builder<\/em>()\n            .firstName(\"test\")\n            .lastName(\"user\")\n            .email(\"test.user@docketdynamics.com\")\n            .phoneNumber(\"(123)654-7890\")\n            .build();\n\n    HttpHeaders headers = new HttpHeaders();\n    headers.set(HttpHeaders.CONTENT_TYPE<\/em>, MediaType.APPLICATION_JSON_VALUE<\/em>);\n\n    HttpEntity<OrganizerDTO> request = new HttpEntity<>(organizerDTO, headers);\n\n    ResponseEntity<OrganizerDTO> result = restTemplate.postForEntity(uri, request, OrganizerDTO.class);\n\n    \/\/Verify request succeed\n    Assertions.assertEquals<\/em>(201, result.getStatusCodeValue());\n    Long newOrganizerId = result.getBody().getOrganizerId();\n    Assertions.assertTrue<\/em>(newOrganizerId!=null && newOrganizerId>0);\n\n    \/\/verify the state of the database\n    Optional<CustomerEntity> storedEntityOptional = customerDAO.findById(newCustomerId);\nassertTrue<\/em>(storedEntityOptional.isPresent());\n}<\/code><\/pre>\n\n\n\n
In this test we\u2019re telling spring to start up an application context. In that context: start up our web container on a random port. Then we\u2019re making a restTemplate that will make a request to our endpoint (create customer). We then verify the response is correct, but we also make sure that the database has the record we expect.<\/p><\/blockquote>\n\n\n\n
Now we can run the test and get a success. However, we should also run code coverage at this point. In the test configuration window, go to the Code Coverage<\/code> tab and change the packages to include in coverage data<\/code> to reflect our entire package.<\/p>\n\n\n\n
\"\"<\/figure>\n\n\n\n
Run the tests again with coverage enabled and review the report. You should see that the only code that wasn\u2019t covered was some of the Lombok constructors (because we used them in our tests). We\u2019ll fix this later when we add code coverage to our maven build process.<\/p>\n\n\n\n
Why Functional Testing is Better than Integration Testing<\/h3>\n\n\n\n
In previous projects, on different teams, we used a different paradigm of writing tests for each class which involved writing lots of mock objects. There are several problems with these types of tests:<\/p>\n\n\n\n