Integration Test

event-sourcing/etc/event-sourcing.ucls

@@ -122,7 +122,7 @@
       <operations public="true" package="true" protected="true" private="true" static="true"/>    
     </display>  
   </class>  
-  <class id="13" language="java" name="com.iluwatar.event.sourcing.service.AccountService" project="event-sourcing" 
+  <class id="13" language="java" name="AccountService" project="event-sourcing"
     file="/event-sourcing/src/main/java/com/iluwatar/event/sourcing/service/AccountService.java" binary="false" 
     corner="BOTTOM_RIGHT">    
     <position height="-1" width="-1" x="687" y="68"/>    
@@ -132,7 +132,7 @@
       <operations public="true" package="true" protected="true" private="true" static="true"/>    
     </display>  
   </class>  
-  <class id="14" language="java" name="com.iluwatar.event.sourcing.service.MoneyTransactionService" 
+  <class id="14" language="java" name="MoneyTransactionService"
     project="event-sourcing" 
     file="/event-sourcing/src/main/java/com/iluwatar/event/sourcing/service/MoneyTransactionService.java" binary="false" 
     corner="BOTTOM_RIGHT">    

event-sourcing/src/main/java/com/iluwatar/event/sourcing/AccountService.java

@@ -20,14 +20,14 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
-package com.iluwatar.event.sourcing.service;
+package com.iluwatar.event.sourcing;
 
 import com.iluwatar.event.sourcing.api.EventProcessor;
 import com.iluwatar.event.sourcing.event.AccountCreateEvent;
 import java.util.Date;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class AccountService {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/MoneyTransactionService.java

@@ -20,7 +20,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
-package com.iluwatar.event.sourcing.service;
+package com.iluwatar.event.sourcing;
 
 import com.iluwatar.event.sourcing.api.EventProcessor;
 import com.iluwatar.event.sourcing.event.MoneyDepositEvent;
@@ -30,7 +30,7 @@ import java.math.BigDecimal;
 import java.util.Date;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class MoneyTransactionService {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/SequenceIdGenerator.java

@@ -20,10 +20,10 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
-package com.iluwatar.event.sourcing.service;
+package com.iluwatar.event.sourcing;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class SequenceIdGenerator {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/api/DomainEvent.java

@@ -25,7 +25,7 @@ package com.iluwatar.event.sourcing.api;
 import java.io.Serializable;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public abstract class DomainEvent implements Serializable {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/api/EventProcessor.java

@@ -23,7 +23,7 @@
 package com.iluwatar.event.sourcing.api;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public interface EventProcessor {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/api/ProcessorJournal.java

@@ -23,7 +23,7 @@
 package com.iluwatar.event.sourcing.api;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public interface ProcessorJournal {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/app/App.java

@@ -24,62 +24,82 @@ package com.iluwatar.event.sourcing.app;
 
 import com.iluwatar.event.sourcing.journal.JsonFileJournal;
 import com.iluwatar.event.sourcing.processor.DomainEventProcessor;
-import com.iluwatar.event.sourcing.service.AccountService;
+import com.iluwatar.event.sourcing.AccountService;
-import com.iluwatar.event.sourcing.service.MoneyTransactionService;
+import com.iluwatar.event.sourcing.MoneyTransactionService;
 import com.iluwatar.event.sourcing.state.AccountAggregate;
 import java.math.BigDecimal;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Event Sourcing : Instead of storing just the current state of the data in a domain, use an
+ * append-only store to record the full series of actions taken on that data. The store acts as the
+ * system of record and can be used to materialize the domain objects. This can simplify tasks in
+ * complex domains, by avoiding the need to synchronize the data model and the business domain,
+ * while improving performance, scalability, and responsiveness. It can also provide consistency for
+ * transactional data, and maintain full audit trails and history that can enable compensating
+ * actions.
+ *
+ * This App class is an example usage of Event Sourcing pattern. As an example, two bank account is
+ * created, then some money deposit and transfer actions are taken so a new state of accounts is
+ * created. At that point, state is cleared in order to represent a system shot down. After the shot
+ * down, system state is recovered by re-creating the past events from event journal. Then state is
+ * printed so a user can view the last state is same with the state before system shot down.
+ *
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class App {
 
+  private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
+  public static final int ACCOUNT_OF_DAENERYS = 1;
+  public static final int ACCOUNT_OF_JON = 2;
+
   /**
    * The entry point of application.
    *
    * @param args the input arguments
    */
   public static void main(String[] args) {
-    System.out.println("Running the system first time............");
 
     DomainEventProcessor domainEventProcessor = new DomainEventProcessor();
     JsonFileJournal jsonFileJournal = new JsonFileJournal();
-    jsonFileJournal.reset();
     domainEventProcessor.setPrecessorJournal(jsonFileJournal);
-
-    System.out.println("Creating th accounts............");
-
     AccountService accountService = new AccountService(domainEventProcessor);
     MoneyTransactionService moneyTransactionService = new MoneyTransactionService(
         domainEventProcessor);
-    accountService.createAccount(1, "Daenerys Targaryen");
-    accountService.createAccount(2, "Jon Snow");
 
-    System.out.println("Do some money operations............");
+    LOGGER.info("Running the system first time............");
+    jsonFileJournal.reset();
 
-    moneyTransactionService.depositMoney(1, new BigDecimal("100000"));
+    LOGGER.info("Creating th accounts............");
-    moneyTransactionService.depositMoney(2, new BigDecimal("100"));
 
-    moneyTransactionService.transferMoney(1, 2, new BigDecimal("10000"));
+    accountService.createAccount(ACCOUNT_OF_DAENERYS, "Daenerys Targaryen");
-    moneyTransactionService.withdrawalMoney(2, new BigDecimal("1000"));
+    accountService.createAccount(ACCOUNT_OF_JON, "Jon Snow");
 
-    System.out.println("...............State:............");
+    LOGGER.info("Do some money operations............");
-    System.out.println(AccountAggregate.getAccount(1));
-    System.out.println(AccountAggregate.getAccount(2));
 
-    System.out.println("At that point system goes down state in memory cleared............");
+    moneyTransactionService.depositMoney(ACCOUNT_OF_DAENERYS, new BigDecimal("100000"));
+    moneyTransactionService.depositMoney(ACCOUNT_OF_JON, new BigDecimal("100"));
 
+    moneyTransactionService.transferMoney(ACCOUNT_OF_DAENERYS, ACCOUNT_OF_JON, new BigDecimal("10000"));
+    moneyTransactionService.withdrawalMoney(ACCOUNT_OF_JON, new BigDecimal("1000"));
+
+    LOGGER.info("...............State:............");
+    LOGGER.info(AccountAggregate.getAccount(ACCOUNT_OF_DAENERYS).toString());
+    LOGGER.info(AccountAggregate.getAccount(ACCOUNT_OF_JON).toString());
+
+    LOGGER.info("At that point system had a shot down, state in memory is cleared............");
     AccountAggregate.resetState();
 
-    System.out.println("Recover the syste by the events in journal file............");
+    LOGGER.info("Recover the system by the events in journal file............");
 
     domainEventProcessor = new DomainEventProcessor();
     jsonFileJournal = new JsonFileJournal();
     domainEventProcessor.setPrecessorJournal(jsonFileJournal);
     domainEventProcessor.recover();
 
-    System.out.println("...............State Recovered:............");
+    LOGGER.info("...............Recovered State:............");
-    System.out.println(AccountAggregate.getAccount(1));
+    LOGGER.info(AccountAggregate.getAccount(ACCOUNT_OF_DAENERYS).toString());
-    System.out.println(AccountAggregate.getAccount(2));
+    LOGGER.info(AccountAggregate.getAccount(ACCOUNT_OF_JON).toString());
   }
 }

event-sourcing/src/main/java/com/iluwatar/event/sourcing/domain/Account.java

@@ -33,7 +33,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class Account {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/domain/Transaction.java

@@ -25,7 +25,7 @@ package com.iluwatar.event.sourcing.domain;
 import java.math.BigDecimal;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class Transaction {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/event/AccountCreateEvent.java

@@ -27,7 +27,7 @@ import com.iluwatar.event.sourcing.domain.Account;
 import com.iluwatar.event.sourcing.state.AccountAggregate;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class AccountCreateEvent extends DomainEvent {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/event/MoneyDepositEvent.java

@@ -28,7 +28,7 @@ import com.iluwatar.event.sourcing.state.AccountAggregate;
 import java.math.BigDecimal;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class MoneyDepositEvent extends DomainEvent {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/event/MoneyTransferEvent.java

@@ -28,7 +28,7 @@ import com.iluwatar.event.sourcing.state.AccountAggregate;
 import java.math.BigDecimal;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class MoneyTransferEvent extends DomainEvent {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/event/MoneyWithdrawalEvent.java

@@ -28,7 +28,7 @@ import com.iluwatar.event.sourcing.state.AccountAggregate;
 import java.math.BigDecimal;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class MoneyWithdrawalEvent extends DomainEvent {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/gateway/AccountCreateContractSender.java

@@ -25,7 +25,7 @@ package com.iluwatar.event.sourcing.gateway;
 import com.iluwatar.event.sourcing.domain.Account;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class AccountCreateContractSender {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/gateway/Gateways.java

@@ -23,7 +23,7 @@
 package com.iluwatar.event.sourcing.gateway;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class Gateways {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/gateway/TransactionLogger.java

@@ -25,7 +25,7 @@ package com.iluwatar.event.sourcing.gateway;
 import com.iluwatar.event.sourcing.domain.Transaction;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class TransactionLogger {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/journal/JsonFileJournal.java

@@ -44,7 +44,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class JsonFileJournal implements ProcessorJournal {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/processor/DomainEventProcessor.java

@@ -27,7 +27,7 @@ import com.iluwatar.event.sourcing.api.EventProcessor;
 import com.iluwatar.event.sourcing.api.ProcessorJournal;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class DomainEventProcessor implements EventProcessor {
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/state/AccountAggregate.java

@@ -27,7 +27,7 @@ import java.util.HashMap;
 import java.util.Map;
 
 /**
- * Created by serdarh on 06.08.2017.
+ * Created by Serdar Hamzaogullari on 06.08.2017.
  */
 public class AccountAggregate {
 

event-sourcing/src/main/test/java/com/iluwatar/event/sourcing/IntegrationTest.java

@@ -0,0 +1,115 @@
+/**
+ * The MIT License
+ * Copyright (c) 2014 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package com.iluwatar.event.sourcing;
+
+import static com.iluwatar.event.sourcing.app.App.ACCOUNT_OF_DAENERYS;
+import static com.iluwatar.event.sourcing.app.App.ACCOUNT_OF_JON;
+
+import com.iluwatar.event.sourcing.domain.Account;
+import com.iluwatar.event.sourcing.journal.JsonFileJournal;
+import com.iluwatar.event.sourcing.processor.DomainEventProcessor;
+import com.iluwatar.event.sourcing.state.AccountAggregate;
+import java.math.BigDecimal;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+/**
+ * Intergartion Test for Event Sourcing state recovery
+ *
+ * Created by Serdar Hamzaogullari on 19.08.2017.
+ */
+public class IntegrationTest {
+
+  /**
+   * The Domain event processor.
+   */
+  DomainEventProcessor domainEventProcessor;
+  /**
+   * The Json file journal.
+   */
+  JsonFileJournal jsonFileJournal;
+  /**
+   * The Account service.
+   */
+  AccountService accountService;
+  /**
+   * The Money transaction service.
+   */
+  MoneyTransactionService moneyTransactionService;
+
+  /**
+   * Initialize.
+   */
+  @Before
+  public void initialize() {
+    domainEventProcessor = new DomainEventProcessor();
+    jsonFileJournal = new JsonFileJournal();
+    domainEventProcessor.setPrecessorJournal(jsonFileJournal);
+    accountService = new AccountService(domainEventProcessor);
+    moneyTransactionService = new MoneyTransactionService(
+        domainEventProcessor);
+  }
+
+  /**
+   * Test state recovery.
+   */
+  @Test
+  public void testStateRecovery() {
+    jsonFileJournal.reset();
+
+    accountService.createAccount(ACCOUNT_OF_DAENERYS, "Daenerys Targaryen");
+    accountService.createAccount(ACCOUNT_OF_JON, "Jon Snow");
+
+    moneyTransactionService.depositMoney(ACCOUNT_OF_DAENERYS, new BigDecimal("100000"));
+    moneyTransactionService.depositMoney(ACCOUNT_OF_JON, new BigDecimal("100"));
+
+    moneyTransactionService
+        .transferMoney(ACCOUNT_OF_DAENERYS, ACCOUNT_OF_JON, new BigDecimal("10000"));
+    moneyTransactionService.withdrawalMoney(ACCOUNT_OF_JON, new BigDecimal("1000"));
+
+    Account accountOfDaenerysBeforeShotDown = AccountAggregate.getAccount(ACCOUNT_OF_DAENERYS);
+    Account accountOfJonBeforeShotDown = AccountAggregate.getAccount(ACCOUNT_OF_JON);
+
+    AccountAggregate.resetState();
+
+    domainEventProcessor = new DomainEventProcessor();
+    jsonFileJournal = new JsonFileJournal();
+    domainEventProcessor.setPrecessorJournal(jsonFileJournal);
+    domainEventProcessor.recover();
+
+    Account accountOfDaenerysAfterShotDown = AccountAggregate.getAccount(ACCOUNT_OF_DAENERYS);
+    Account accountOfJonAfterShotDown = AccountAggregate.getAccount(ACCOUNT_OF_JON);
+
+    Assert.assertEquals(accountOfDaenerysBeforeShotDown.getMoney(),
+        accountOfDaenerysAfterShotDown.getMoney());
+    Assert
+        .assertEquals(accountOfJonBeforeShotDown.getMoney(), accountOfJonAfterShotDown.getMoney());
+    Assert.assertEquals(accountOfDaenerysBeforeShotDown.getTransactions().size(),
+        accountOfDaenerysAfterShotDown.getTransactions().size());
+    Assert.assertEquals(accountOfJonBeforeShotDown.getTransactions().size(),
+        accountOfJonAfterShotDown.getTransactions().size());
+
+  }
+
+}