build.gradle

plugins {
    id 'java'
    id 'idea'
    id 'org.springframework.boot' version '2.1.8.RELEASE'
    id 'io.spring.dependency-management' version '1.0.8.RELEASE'
}

group 'com.octo.skool13'
sourceCompatibility = 11

repositories {
    mavenCentral()
}

dependencies {
    // Web
    implementation 'org.springframework.boot:spring-boot-starter-web'

    // Tests
    testImplementation 'org.springframework.boot:spring-boot-starter-test'
    testImplementation 'junit:junit:4.12'
}

HealthcheckApi.java

@RestController
public class HealthcheckApi {

    private final SayImAlive sayImAlive;

    public HealthcheckApi(SayImAlive sayImAlive) {
        this.sayImAlive = sayImAlive;
    }

    @RequestMapping(value = "/healthcheck")
    public Boolean healthcheck() {
        return sayImAlive.execute();
    }
}

HealthcheckApiTest.java

package com.octo.skool13.infra;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;

import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;

@RunWith(SpringRunner.class)
@SpringBootTest
@AutoConfigureMockMvc
public class HealthcheckApiTest {

    @Autowired
    private MockMvc mvc;

    @Test
    public void isAlive() throws Exception {
        mvc.perform(MockMvcRequestBuilders.get("/healthcheck"))
            .andExpect(status().isOk())
            .andExpect(content().string("true"));
    }
}

ManageoApplication.java

package com.octo.skool13;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class ManageoApplication {

    public static void main(String[] args) {
        SpringApplication.run(ManageoApplication.class, args);
    }
}