Add redis persist sample

- New sample app eventservice which is used to
  demonstrate how redis is used as a repository
  for StateMachineContext.
- Uses pooled request scope machine instances so
  that with every request a machine is reseted from
  a redis.
- Provides UI to play around.
- Provides rest endpoint to send 'pageview' events
  for processing. For example using curl command like:
  curl http://localhost:8080/feed -H "Content-Type: application/json" --data '{"user":"joe","id":"VIEW_I"}'
- Fixes #160

build.gradle

@@ -226,7 +226,8 @@ configure(sampleProjects()) {
 	configurations.archives.artifacts.removeAll { it.archiveTask.is jar }
 	tasks.findByPath("artifactoryPublish")?.enabled = false
 	dependencies {
-		compile project(":spring-statemachine-samples-common")
+//		compile project(":spring-statemachine-samples-common")
+		compile project(":spring-statemachine-core")
 		compile "org.springframework:spring-context-support:$springVersion"
 		testCompile "org.springframework:spring-test:$springVersion"
 		testCompile "org.hamcrest:hamcrest-core:$hamcrestVersion"

settings.gradle

@@ -19,6 +19,7 @@ include 'spring-statemachine-samples:persist'
 include 'spring-statemachine-samples:web'
 include 'spring-statemachine-samples:scope'
 include 'spring-statemachine-samples:security'
+include 'spring-statemachine-samples:eventservice'
 
 rootProject.children.find {
 	if (it.name == 'spring-statemachine-recipes') {

spring-statemachine-core/src/main/java/org/springframework/statemachine/support/ObservableMap.java

@@ -132,6 +132,11 @@ public class ObservableMap<K, V> implements Map<K, V> {
 		return delegate.entrySet();
 	}
 
+	@Override
+	public String toString() {
+		return delegate.toString();
+	}
+
 	/**
 	 * Gets the delegating map instance.
 	 *

spring-statemachine-samples/build.gradle

@@ -2,27 +2,43 @@ description = 'Spring State Machine Samples Common'
 
 project('spring-statemachine-samples-turnstile') {
 	description = 'Spring State Machine Turnstile Sample'
+	dependencies {
+		compile project(":spring-statemachine-samples-common")
+	}
 }
 
 project('spring-statemachine-samples-showcase') {
 	description = 'Spring State Machine Showcase Sample'
+	dependencies {
+		compile project(":spring-statemachine-samples-common")
+	}
 }
 
 project('spring-statemachine-samples-cdplayer') {
 	description = 'Spring State Machine CD Player Sample'
+	dependencies {
+		compile project(":spring-statemachine-samples-common")
+	}
 }
 
 project('spring-statemachine-samples-tasks') {
 	description = 'Spring State Machine Parallel Regions Sample'
+	dependencies {
+		compile project(":spring-statemachine-samples-common")
+	}
 }
 
 project('spring-statemachine-samples-washer') {
 	description = 'Spring State Machine History State Sample'
+	dependencies {
+		compile project(":spring-statemachine-samples-common")
+	}
 }
 
 project('spring-statemachine-samples-zookeeper') {
 	description = 'Spring State Machine Distributed Sample'
 	dependencies {
+		compile project(":spring-statemachine-samples-common")
 		compile project(":spring-statemachine-zookeeper")
 	}
 }
@@ -30,6 +46,7 @@ project('spring-statemachine-samples-zookeeper') {
 project('spring-statemachine-samples-persist') {
 	description = 'Spring State Machine Persist Sample'
 	dependencies {
+		compile project(":spring-statemachine-samples-common")
 		compile project(":spring-statemachine-recipes-common")
 		compile ("org.hsqldb:hsqldb:2.3.1")
 		compile ("org.springframework:spring-jdbc:$springVersion")
@@ -66,3 +83,13 @@ project('spring-statemachine-samples-security') {
 		compile("org.springframework.security:spring-security-web:$springSecurityVersion")
 	}
 }
+
+project('spring-statemachine-samples-eventservice') {
+	description = 'Spring State Machine Event Service Sample'
+	dependencies {
+		compile project(":spring-statemachine-redis")
+		compile("org.springframework.boot:spring-boot-starter-thymeleaf:$springBootVersion")
+//		compile("org.springframework.boot:spring-boot-starter-redis:$springBootVersion")
+		compile("org.apache.commons:commons-pool2:2.4.2")
+	}
+}

spring-statemachine-samples/eventservice/src/main/java/demo/eventservice/Application.java

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package demo.eventservice;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class Application {
+
+	public static void main(String[] args) {
+		SpringApplication.run(Application.class, args);
+	}
+}

spring-statemachine-samples/eventservice/src/main/java/demo/eventservice/Pageview.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package demo.eventservice;
+
+import demo.eventservice.StateMachineConfig.Events;
+
+public class Pageview {
+
+	private String user;
+	private Events id;
+
+	public String getUser() {
+		return user;
+	}
+
+	public void setUser(String user) {
+		this.user = user;
+	}
+
+	public Events getId() {
+		return id;
+	}
+
+	public void setId(Events id) {
+		this.id = id;
+	}
+
+	@Override
+	public String toString() {
+		return "Pageview [user=" + user + ", id=" + id + "]";
+	}
+
+}

spring-statemachine-samples/eventservice/src/main/java/demo/eventservice/StateMachineConfig.java

@@ -0,0 +1,235 @@
+/*
+ * Copyright 2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package demo.eventservice;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.EnumSet;
+import java.util.Scanner;
+
+import org.springframework.aop.framework.ProxyFactoryBean;
+import org.springframework.aop.target.CommonsPool2TargetSource;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Scope;
+import org.springframework.context.annotation.ScopedProxyMode;
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.data.redis.connection.RedisConnectionFactory;
+import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;
+import org.springframework.statemachine.StateContext;
+import org.springframework.statemachine.StateMachine;
+import org.springframework.statemachine.StateMachinePersist;
+import org.springframework.statemachine.action.Action;
+import org.springframework.statemachine.config.StateMachineBuilder;
+import org.springframework.statemachine.config.StateMachineBuilder.Builder;
+import org.springframework.statemachine.redis.RedisStateMachineContextRepository;
+import org.springframework.statemachine.support.RepositoryStateMachinePersist;
+
+@Configuration
+public class StateMachineConfig {
+
+	@Bean
+	@Scope(value = "request", proxyMode = ScopedProxyMode.TARGET_CLASS)
+	public ProxyFactoryBean stateMachine() {
+		ProxyFactoryBean pfb = new ProxyFactoryBean();
+		pfb.setTargetSource(poolTargetSource());
+		return pfb;
+	}
+
+	@Bean
+	public CommonsPool2TargetSource poolTargetSource() {
+		CommonsPool2TargetSource pool = new CommonsPool2TargetSource();
+		pool.setMaxSize(3);
+		pool.setTargetBeanName("stateMachineTarget");
+		return pool;
+	}
+
+	@Bean(name = "stateMachineTarget")
+	@Scope(scopeName="prototype")
+	public StateMachine<States, Events> stateMachineTarget() throws Exception {
+		Builder<States, Events> builder = StateMachineBuilder.<States, Events>builder();
+
+		builder.configureConfiguration()
+			.withConfiguration()
+				.autoStartup(true);
+
+		builder.configureStates()
+			.withStates()
+				.initial(States.HOME)
+				.states(EnumSet.allOf(States.class));
+
+		builder.configureTransitions()
+			.withInternal()
+				.source(States.ITEMS).event(Events.ADD)
+				.action(addAction())
+				.and()
+			.withInternal()
+				.source(States.CART).event(Events.DEL)
+				.action(delAction())
+				.and()
+			.withInternal()
+				.source(States.PAYMENT).event(Events.PAY)
+				.action(payAction())
+				.and()
+			.withExternal()
+				.source(States.HOME).target(States.ITEMS)
+				.action(pageviewAction())
+				.event(Events.VIEW_I)
+				.and()
+			.withExternal()
+				.source(States.CART).target(States.ITEMS)
+				.action(pageviewAction())
+				.event(Events.VIEW_I)
+				.and()
+			.withExternal()
+				.source(States.ITEMS).target(States.CART)
+				.action(pageviewAction())
+				.event(Events.VIEW_C)
+				.and()
+			.withExternal()
+				.source(States.PAYMENT).target(States.CART)
+				.action(pageviewAction())
+				.event(Events.VIEW_C)
+				.and()
+			.withExternal()
+				.source(States.CART).target(States.PAYMENT)
+				.action(pageviewAction())
+				.event(Events.VIEW_P)
+				.and()
+			.withExternal()
+				.source(States.ITEMS).target(States.HOME)
+				.action(resetAction())
+				.event(Events.RESET)
+				.and()
+			.withExternal()
+				.source(States.CART).target(States.HOME)
+				.action(resetAction())
+				.event(Events.RESET)
+				.and()
+			.withExternal()
+				.source(States.PAYMENT).target(States.HOME)
+				.action(resetAction())
+				.event(Events.RESET);
+
+		return builder.build();
+	}
+
+	@Bean
+	public Action<States, Events> pageviewAction() {
+		return new Action<States, Events>() {
+
+			@Override
+			public void execute(StateContext<States, Events> context) {
+				String variable = context.getTarget().getId().toString();
+				Integer count = context.getExtendedState().get(variable, Integer.class);
+				if (count == null) {
+					context.getExtendedState().getVariables().put(variable, 1);
+				} else {
+					context.getExtendedState().getVariables().put(variable, (count + 1));
+				}
+			}
+		};
+	}
+
+	@Bean
+	public Action<States, Events> addAction() {
+		return new Action<States, Events>() {
+
+			@Override
+			public void execute(StateContext<States, Events> context) {
+				Integer count = context.getExtendedState().get("COUNT", Integer.class);
+				if (count == null) {
+					context.getExtendedState().getVariables().put("COUNT", 1);
+				} else {
+					context.getExtendedState().getVariables().put("COUNT", (count + 1));
+				}
+			}
+		};
+	}
+
+	@Bean
+	public Action<States, Events> delAction() {
+		return new Action<States, Events>() {
+
+			@Override
+			public void execute(StateContext<States, Events> context) {
+				Integer count = context.getExtendedState().get("COUNT", Integer.class);
+				if (count != null && count > 0) {
+					context.getExtendedState().getVariables().put("COUNT", (count - 1));
+				}
+			}
+		};
+	}
+
+	@Bean
+	public Action<States, Events> payAction() {
+		return new Action<States, Events>() {
+
+			@Override
+			public void execute(StateContext<States, Events> context) {
+				context.getExtendedState().getVariables().put("PAYED", true);
+			}
+		};
+	}
+
+	@Bean
+	public Action<States, Events> resetAction() {
+		return new Action<States, Events>() {
+
+			@Override
+			public void execute(StateContext<States, Events> context) {
+				context.getExtendedState().getVariables().clear();
+			}
+		};
+	}
+
+	@Bean
+	public RedisConnectionFactory redisConnectionFactory() {
+		return new JedisConnectionFactory();
+	}
+
+	@Bean
+	public StateMachinePersist<States, Events, String> stateMachinePersist(RedisConnectionFactory connectionFactory) {
+		return new RepositoryStateMachinePersist<States, Events>(new RedisStateMachineContextRepository<States, Events>(connectionFactory));
+	}
+
+	@Bean
+	public String stateChartModel() throws IOException {
+		ClassPathResource model = new ClassPathResource("statechartmodel.txt");
+		InputStream inputStream = model.getInputStream();
+		Scanner scanner = new Scanner(inputStream);
+		String content = scanner.useDelimiter("\\Z").next();
+		scanner.close();
+		return content;
+	}
+
+	public enum States {
+		HOME,
+		ITEMS,
+		CART,
+		PAYMENT
+	}
+
+	public enum Events {
+		VIEW_I,
+		VIEW_C,
+		VIEW_P,
+		RESET,
+		ADD,
+		DEL,
+		PAY
+	}
+}

spring-statemachine-samples/eventservice/src/main/java/demo/eventservice/StateMachineController.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright 2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package demo.eventservice;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpStatus;
+import org.springframework.statemachine.StateMachine;
+import org.springframework.statemachine.StateMachineContext;
+import org.springframework.statemachine.StateMachinePersist;
+import org.springframework.statemachine.access.StateMachineAccess;
+import org.springframework.statemachine.access.StateMachineFunction;
+import org.springframework.statemachine.support.DefaultStateMachineContext;
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.util.Assert;
+import org.springframework.util.StringUtils;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.ResponseStatus;
+
+import demo.eventservice.StateMachineConfig.Events;
+import demo.eventservice.StateMachineConfig.States;
+
+@Controller
+public class StateMachineController {
+
+	@Autowired
+	private StateMachine<States, Events> stateMachine;
+
+	@Autowired
+	private StateMachinePersist<States, Events, String> stateMachinePersist;
+
+	@Autowired
+	private String stateChartModel;
+
+	@RequestMapping("/")
+	public String home() {
+		return "redirect:/state";
+	}
+
+	@RequestMapping("/state")
+	public String feedAndGetState(@RequestParam(value = "user", required = false) String user,
+			@RequestParam(value = "id", required = false) Events id, Model model) throws Exception {
+		model.addAttribute("user", user);
+		model.addAttribute("allTypes", Events.values());
+		model.addAttribute("stateChartModel", stateChartModel);
+		// we may get into this page without a user so
+		// do nothing with a state machine
+		if (StringUtils.hasText(user)) {
+			resetStateMachineFromStore(user);
+			if (id != null) {
+				feedMachine(user, id);
+			}
+			model.addAttribute("states", stateMachine.getState().getIds());
+			model.addAttribute("extendedState", stateMachine.getExtendedState().getVariables());
+		}
+		return "states";
+	}
+
+	@RequestMapping(value = "/feed",method= RequestMethod.POST)
+	@ResponseStatus(HttpStatus.OK)
+	public void feedPageview(@RequestBody(required = true) Pageview event) throws Exception {
+		Assert.notNull(event.getUser(), "User must be set");
+		Assert.notNull(event.getId(), "Id must be set");
+		resetStateMachineFromStore(event.getUser());
+		feedMachine(event.getUser(), event.getId());
+	}
+
+	private void feedMachine(String user, Events id) throws Exception {
+		stateMachine.sendEvent(id);
+		stateMachinePersist.write(new DefaultStateMachineContext<States, Events>(stateMachine.getState().getId(), null, null,
+				stateMachine.getExtendedState()), "testprefix:" + user);
+	}
+
+	private StateMachine<States, Events> resetStateMachineFromStore(String user) throws Exception {
+		final StateMachineContext<States, Events> context = stateMachinePersist.read("testprefix:" + user);
+		stateMachine.stop();
+		stateMachine.getStateMachineAccessor()
+			.doWithAllRegions(new StateMachineFunction<StateMachineAccess<States, Events>>() {
+
+			@Override
+			public void apply(StateMachineAccess<States, Events> function) {
+				function.resetStateMachine(context);
+			}
+		});
+		stateMachine.start();
+		return stateMachine;
+	}
+}

spring-statemachine-samples/eventservice/src/main/resources/application.yml

@@ -0,0 +1,3 @@
+security:
+  basic:
+    enabled: false

spring-statemachine-samples/eventservice/src/main/resources/logback.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+
+		<include resource="org/springframework/boot/logging/logback/base.xml"/>
+
+		<logger name="org.springframework" level="INFO"/>
+		<logger name="org.springframework.statemachine" level="DEBUG"/>
+
+</configuration>

spring-statemachine-samples/eventservice/src/main/resources/statechartmodel.txt

@@ -0,0 +1,20 @@
++---------------------------------------------------------------------------------------------------------------------+
+|                                                     SM                                                              |
++---------------------------------------------------------------------------------------------------------------------+
+|                                                                                                                     |
+|     +------------------+  VIEW_I  +------------------+  VIEW_C  +------------------+  VIEW_P  +------------------+  |
+| *-->|       HOME       |--------->|       ITEMS      |--------->|       CART       |--------->|      PAYMENT     |  |
+|     |                  |          |                  |          |                  |          |                  |  |
+|     |                  |          |       ADD        |          |       DEL        |          |       PAY        |  |
+|     |                  |          |  +------------+  |          |  +------------+  |          |  +------------+  |  |
+|     |                  |  RESET   |  |            |  |  VIEW_I  |  |            |  |  VIEW_C  |  |            |  |  |
+|     |                  |<---------|  |            v  |<---------|  |            v  |<---------|  |            v  |  |
+|     +------------------+          +------------------+          +------------------+          +------------------+  |
+|          ^       ^                              ^                     |                             |       |       |
+|          |       |              RESET           |                     |                             |       |       |
+|          |       +----------------------------------------------------+                             |       |       |
+|          |                                      |                           VIEW_I                  |       |       |
+|          |             RESET                    +---------------------------------------------------+       |       |
+|          +--------------------------------------------------------------------------------------------------+       |
+|                                                                                                                     |
++---------------------------------------------------------------------------------------------------------------------+

spring-statemachine-samples/eventservice/src/main/resources/templates/states.html

@@ -0,0 +1,28 @@
+<!DOCTYPE HTML>
+<html xmlns:th="http://www.thymeleaf.org">
+<head>
+	<title>Spring Statemachine Event Service Demo</title>
+	<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
+</head>
+<body>
+	<div th:if="${user != null}">
+		<p th:text="'User: ' + ${user}" />
+		<p th:text="'States: ' + ${states}" />
+		<p th:text="'Extended State: ' + ${extendedState}" />
+	</div>
+
+	<form action="#" data-th-action="@{/state}" data-th-object="${model}" method="post">
+		<ul>
+			<li th:each="ty : ${allTypes}">
+				<input type="radio" name="id" th:value="${ty}" />
+				<label th:text="${ty}">replaced</label>
+			</li>
+		</ul>
+		<button type="submit" name="user" value="joe">joe</button>
+		<button type="submit" name="user" value="bob">bob</button>
+		<button type="submit" name="user" value="dave">dave</button>
+	</form>
+
+	<pre th:text="${stateChartModel}"/>
+</body>
+</html>

spring-statemachine-samples/eventservice/src/test/java/demo/eventservice/EventServiceTests.java

@@ -0,0 +1,131 @@
+/*
+ * Copyright 2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package demo.eventservice;
+
+import static org.hamcrest.Matchers.containsString;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import java.util.HashMap;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.SpringApplicationConfiguration;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.MediaType;
+import org.springframework.statemachine.StateMachineContext;
+import org.springframework.statemachine.StateMachinePersist;
+import org.springframework.test.annotation.DirtiesContext;
+import org.springframework.test.annotation.DirtiesContext.ClassMode;
+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.setup.MockMvcBuilders;
+import org.springframework.web.context.WebApplicationContext;
+
+import demo.eventservice.EventServiceTests.Config;
+import demo.eventservice.StateMachineConfig.Events;
+import demo.eventservice.StateMachineConfig.States;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@SpringApplicationConfiguration(classes = { Application.class, Config.class })
+@WebAppConfiguration
+@DirtiesContext(classMode = ClassMode.AFTER_EACH_TEST_METHOD)
+public class EventServiceTests {
+
+	private MockMvc mvc;
+
+	@Autowired
+	private WebApplicationContext context;
+
+	@Test
+	public void testHome() throws Exception {
+		mvc.
+			perform(get("/state")).
+			andExpect(status().isOk());
+	}
+
+	@Test
+	public void testSendEvent() throws Exception {
+		mvc.
+			perform(get("/state").param("user", "joe").param("id", "VIEW_I")).
+			andExpect(status().isOk()).
+			andExpect(content().string(containsString("States: [ITEMS]")));
+	}
+
+	@Test
+	public void testAdd() throws Exception {
+		mvc.
+			perform(get("/state").param("user", "joe").param("id", "VIEW_I")).
+			andExpect(status().isOk()).
+			andExpect(content().string(containsString("States: [ITEMS]")));
+		mvc.
+			perform(get("/state").param("user", "joe").param("id", "ADD")).
+			andExpect(status().isOk()).
+			andExpect(content().string(containsString("States: [ITEMS]"))).
+			andExpect(content().string(containsString("Extended State: {COUNT=1, ITEMS=1}")));
+	}
+
+	@Test
+	public void testFeed() throws Exception {
+		mvc.
+			perform(post("/feed").content("{\"user\":\"joe\",\"id\":\"VIEW_I\"}").contentType(MediaType.APPLICATION_JSON)).
+			andExpect(status().isOk());
+		mvc.
+			perform(post("/feed").content("{\"user\":\"joe\",\"id\":\"ADD\"}").contentType(MediaType.APPLICATION_JSON)).
+			andExpect(status().isOk());
+		mvc.
+			perform(get("/state").param("user", "joe")).
+			andExpect(status().isOk()).
+			andExpect(content().string(containsString("States: [ITEMS]"))).
+			andExpect(content().string(containsString("Extended State: {COUNT=1, ITEMS=1}")));
+	}
+
+	@Before
+	public void setup() throws Exception {
+		mvc = MockMvcBuilders.webAppContextSetup(context).build();
+	}
+
+	@Configuration
+	static class Config {
+
+		@Bean
+		public StateMachinePersist<States, Events, String> stateMachinePersist() {
+			// use stateMachinePersist without redis to ease testing
+			return new InMemoryStateMachinePersist();
+		}
+	}
+
+	static class InMemoryStateMachinePersist implements StateMachinePersist<States, Events, String> {
+
+		private final HashMap<String, StateMachineContext<States, Events>> contexts = new HashMap<>();
+
+		@Override
+		public void write(StateMachineContext<States, Events> context, String contextOjb) throws Exception {
+			contexts.put(contextOjb, context);
+		}
+
+		@Override
+		public StateMachineContext<States, Events> read(String contextOjb) throws Exception {
+			return contexts.get(contextOjb);
+		}
+	}
+}