Fix tests up a bit and add documemtation

See gh-18

README.adoc

@@ -136,6 +136,44 @@ $ curl localhost:8080
 Greetings from Spring Boot!
 ....
 
+== Add Unit Tests
+
+You will want to add a test for the endpoint you added, and Spring Test already provides some machinery for that, and it's easy to include in your project.
+
+Add this to your build file's list of dependencies:
+
+[source,groovy]
+----
+include::complete/build.gradle[tag=tests]
+----
+
+If you are using Maven, add this to your list of dependencies:
+
+[source,xml]
+----
+include::complete/pom.xml[tag=tests]
+----
+
+Now write a simple unit test that mocks the servlet request and response through your endpoint:
+
+`src/test/java/hello/HelloControllerTest.java`
+[source,java]
+----
+include::initial/src/test/java/hello/HelloControllerTest.java[]
+----
+
+Note the use of the `MockServletContext` to set up an empty `WebApplicationContext` so the `HelloController` can be created in the `@Before` and passed to `MockMvcBuilders.standaloneSetup()`. An alternative would be to create the full application context using the `Application` class and `@Autowired` the `HelloController` into the test. The `MockMvc` comes from Spring Test and allows you, via a set of convenient builder classes, to send HTTP requests into the `DispatcherServlet` and make assertions about the result.
+
+As well as mocking the HTTP request cycle we can also use Spring Boot to write a very simple full-stack integration test. For example, instead of (or as well as) the mock test above we could do this:
+
+`src/test/java/hello/HelloControllerTest.java`
+[source,java]
+----
+include::initial/src/test/java/hello/HelloControllerIT.java[]
+----
+
+The embedded server is started up on a random port by virtue of the `@IntegrationTest("${server.port=0}")` and the actual port is discovered at runtime with the `@Value("${local.server.port}")`.
+
 == Add production-grade services
 If you are building a web site for your business, you probably need to add some management services. Spring Boot provides several out of the box with its http://docs.spring.io/spring-boot/docs/{spring_boot_version}/reference/htmlsingle/#production-ready[actuator module], such as health, audits, beans, and more.
 

complete/build.gradle

@@ -26,7 +26,9 @@ dependencies {
     // tag::actuator[]
     compile("org.springframework.boot:spring-boot-starter-actuator")
     // end::actuator[]
+    // tag::tests[]
     testCompile("org.springframework.boot:spring-boot-starter-test")
+    // end::tests[]
 }
 
 task wrapper(type: Wrapper) {

complete/pom.xml

@@ -24,11 +24,13 @@
             <artifactId>spring-boot-starter-actuator</artifactId>
         </dependency>
         <!-- end::actuator[] -->
+        <!-- tag::tests[] -->
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>
             <scope>test</scope>
         </dependency>
+        <!-- end::tests[] -->
     </dependencies>
 
     <properties>

complete/src/main/java/hello/HelloController.java

@@ -6,7 +6,7 @@
 @RestController
 public class HelloController {
 
-    @RequestMapping("/hello")
+    @RequestMapping("/")
     public String index() {
         return "Greetings from Spring Boot!";
     }

complete/src/test/java/hello/HelloControllerIT.java

@@ -1,8 +1,14 @@
 package hello;
 
+import static org.hamcrest.Matchers.is;
+import static org.junit.Assert.assertThat;
+
+import java.net.URL;
+
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Value;
 import org.springframework.boot.test.IntegrationTest;
 import org.springframework.boot.test.SpringApplicationConfiguration;
 import org.springframework.boot.test.TestRestTemplate;
@@ -11,22 +17,21 @@
 import org.springframework.test.context.web.WebAppConfiguration;
 import org.springframework.web.client.RestTemplate;
 
-import java.net.URL;
-
-import static org.hamcrest.Matchers.is;
-import static org.junit.Assert.assertThat;
-
 @RunWith(SpringJUnit4ClassRunner.class)
 @SpringApplicationConfiguration(classes = Application.class)
 @WebAppConfiguration
-@IntegrationTest({"server.port=9090"})
+@IntegrationTest({"server.port=0"})
 public class HelloControllerIT {
+
+    @Value("${local.server.port}")
+    private int port;
+
 	private URL base;
 	private RestTemplate template;
 
 	@Before
 	public void setUp() throws Exception {
-		this.base = new URL("http://localhost:9090/hello");
+		this.base = new URL("http://localhost:" + port + "/");
 		template = new TestRestTemplate();
 	}
 

complete/src/test/java/hello/HelloControllerTest.java

@@ -1,27 +1,26 @@
 package hello;
 
+import static org.hamcrest.Matchers.is;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.boot.test.SpringApplicationConfiguration;
 import org.springframework.http.MediaType;
 import org.springframework.mock.web.MockServletContext;
-import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 import org.springframework.test.context.web.WebAppConfiguration;
 import org.springframework.test.web.servlet.MockMvc;
 import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;
 import org.springframework.test.web.servlet.setup.MockMvcBuilders;
 
-import static org.hamcrest.Matchers.is;
-import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
-import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
-
 @RunWith(SpringJUnit4ClassRunner.class)
-@SpringApplicationConfiguration(classes = Application.class)
-@ContextConfiguration(classes = MockServletContext.class)
+@SpringApplicationConfiguration(classes = MockServletContext.class)
 @WebAppConfiguration
 public class HelloControllerTest {
+
 	private MockMvc mvc;
 
 	@Before
@@ -31,7 +30,7 @@ public void setUp() throws Exception {
 
 	@Test
 	public void getHello() throws Exception {
-		mvc.perform(MockMvcRequestBuilders.get("/hello").accept(MediaType.APPLICATION_JSON))
+		mvc.perform(MockMvcRequestBuilders.get("/").accept(MediaType.APPLICATION_JSON))
 				.andExpect(status().isOk())
 				.andExpect(content().string(is("Greetings from Spring Boot!")));
 	}

initial/pom.xml

@@ -14,28 +14,10 @@
     </parent>
 
     <dependencies>
-	    <!-- tag::jetty[] -->
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-web</artifactId>
-            <exclusions>
-                <exclusion>
-                    <groupId>org.springframework.boot</groupId>
-                    <artifactId>spring-boot-starter-tomcat</artifactId>
-                </exclusion>
-	    </exclusions>
         </dependency>
-        <dependency>
-            <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter-jetty</artifactId>
-        </dependency>
-        <!-- end::jetty[] -->
-        <!-- tag::actuator[] -->
-        <dependency>
-            <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter-actuator</artifactId>
-        </dependency>
-        <!-- end::actuator[] -->
     </dependencies>
 
     <properties>