Java - Spring Boot REST API

Spring Boot REST API

Controller

// src/main/java/com/example/demo/api/GreetController.java
package com.example.demo.api;
import org.springframework.web.bind.annotation.*;

record GreetResponse(String message) {}

@RestController
@RequestMapping("/api")
class GreetController {
  @GetMapping("/greet")
  GreetResponse greet(@RequestParam(defaultValue = "World") String name) {
    return new GreetResponse("Hello, " + name + "!");
  }
}

Run and Test

./mvnw spring-boot:run
# In another terminal
curl "http://localhost:8080/api/greet?name=Ada"

Simple Test

// src/test/java/com/example/demo/api/GreetControllerTest.java
package com.example.demo.api;
import org.junit.jupiter.api.Test;
import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.beans.factory.annotation.Autowired;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;

@SpringBootTest
@AutoConfigureMockMvc
class GreetControllerTest {
  @Autowired MockMvc mvc;
  @Test void greet() throws Exception {
    mvc.perform(get("/api/greet").param("name","Ada"))
      .andExpect(status().isOk())
      .andExpect(jsonPath("$.message").value("Hello, Ada!"));
  }
}