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add orchestrator

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This commit is contained in:
Besok
2019-11-02 20:52:59 +00:00
parent c4c37d77e9
commit 3a4677c56d
16 changed files with 555 additions and 109 deletions
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17
saga/src/main/java/com/iluwatar/saga/orchestration/Chapter.java
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@ -23,13 +23,28 @@
package com.iluwatar.saga.orchestration;
/**
* Chapter including into Saga
* Chapter is an interface representing a contract for an external service.
* @param <K> is type for passing params
*/
public interface Chapter<K> {
/**
* @return service name.
*/
String getName();
/**
* The operation executed in general case.
* @param value incoming value
* @return result {@link ChapterResult}
*/
ChapterResult<K> process(K value);
/**
* The operation executed in rollback case.
* @param value incoming value
* @return result {@link ChapterResult}
*/
ChapterResult<K> rollback(K value);
}

41
saga/src/main/java/com/iluwatar/saga/orchestration/ChapterResult.java
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@ -1,17 +1,52 @@
/*
* The MIT License
* Copyright © 2014-2019 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.saga.orchestration;
/**
* Executing result for chapter
* @param <K> incoming value
*/
public class ChapterResult<K> {
K value;
State state;
private K value;
private State state;
public ChapterResult(K value, State state) {
public K getValue() {
return value;
}
ChapterResult(K value, State state) {
this.value = value;
this.state = state;
}
public boolean isSuccess(){
return state == State.SUCCESS;
}
public static <K> ChapterResult<K> success(K val) {
return new ChapterResult<>(val, State.SUCCESS);
}
public static <K> ChapterResult<K> failure(K val) {
return new ChapterResult<>(val, State.FAILURE);
}

25
saga/src/main/java/com/iluwatar/saga/orchestration/FlyBookingService.java
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@ -1,5 +1,30 @@
/*
* The MIT License
* Copyright © 2014-2019 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.saga.orchestration;
/**
* Class representing a service to book a fly
*/
public class FlyBookingService extends Service<String> {
@Override
public String getName() {

42
saga/src/main/java/com/iluwatar/saga/orchestration/HotelBookingService.java
View File

@ -1,8 +1,50 @@
/*
* The MIT License
* Copyright © 2014-2019 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.saga.orchestration;
/**
* Class representing a service to book a hotel
*/
public class HotelBookingService extends Service<String> {
@Override
public String getName() {
return "booking a Hotel";
}
@Override
public ChapterResult<String> rollback(String value) {
if(value.equals("crashed_order")){
logger.info("The Rollback for a chapter '{}' has been started. " +
"The data {} has been failed.The saga has been crashed.",
getName(), value);
return ChapterResult.failure(value);
}
logger.info("The Rollback for a chapter '{}' has been started. The data {} has been rollbacked successfully",
getName(), value);
return super.rollback(value);
}
}

25
saga/src/main/java/com/iluwatar/saga/orchestration/OrderService.java
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@ -1,5 +1,30 @@
/*
* The MIT License
* Copyright © 2014-2019 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.saga.orchestration;
/**
* Class representing a service to init a new order.
*/
public class OrderService extends Service<String> {
@Override
public String getName() {

42
saga/src/main/java/com/iluwatar/saga/orchestration/Saga.java
View File

@ -25,56 +25,50 @@ package com.iluwatar.saga.orchestration;
import java.util.ArrayList;
import java.util.List;
/**
* Saga representation.
* Saca consists of chapters.
* Every Chapter is executed a certain service.
*/
public class Saga {
private List<Chapter> chapters;
private Result result;
public Saga() {
this.chapters = new ArrayList<>();
this.result = Result.INPROCESS;
}
public void setResult(Result result) {
this.result = result;
}
public boolean isSuccess(){
return result == Result.FINISHED;
}
public boolean isFinished(){
return result != Result.INPROCESS;
}
public Saga chapter(String name, int timeoutInSec) {
this.chapters.add(new Chapter(name, timeoutInSec));
public Saga chapter(String name) {
this.chapters.add(new Chapter(name));
return this;
}
public Chapter get(int idx) {
if (chapters.size() < idx || idx < 0) {
throw new SagaException("idx shoud be less then ch size or more then 0");
}
return chapters.get(idx);
}
public boolean isPresent(int idx) {
return idx >= 0 && idx < chapters.size();
}
public static Saga create() {
return new Saga();
}
public enum Result{
FINISHED,CANCELED, INPROCESS;
public enum Result {
FINISHED, ROLLBACK, CRASHED
}
private static class Chapter {
String name;
int timeoutInSec;
public Chapter(String name, int timeoutInSec) {
public static class Chapter {
String name;
public Chapter(String name) {
this.name = name;
this.timeoutInSec = timeoutInSec;
}
}
}

42
saga/src/main/java/com/iluwatar/saga/orchestration/SagaApplication.java
View File

@ -24,22 +24,48 @@
package com.iluwatar.saga.orchestration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* This pattern is used in distributed services to perform a group of operations atomically.
* This is an analog of transaction in a database but in terms of microservices architecture this is executed
* in a distributed environment
*
* A saga is a sequence of local transactions in a certain context. If one transaction fails for some reason,
* the saga executes compensating transactions(rollbacks) to undo the impact of the preceding transactions.
*
* In this approach, there is an orchestrator @see {@link SagaOrchestrator} that manages all the transactions and directs
* the participant services to execute local transactions based on events.
*
* @see Saga
* @see SagaOrchestrator
* @see Service
*/
public class SagaApplication {
private static final Logger logger = LoggerFactory.getLogger(SagaApplication.class);
public static void main(String[] args) {
SagaOrchestrator sagaOrchestrator = new SagaOrchestrator(newSaga(), serviceDiscovery());
Saga.Result goodOrder = sagaOrchestrator.execute("god_order");
Saga.Result badOrder = sagaOrchestrator.execute("bad_order");
Saga.Result crashedOrder = sagaOrchestrator.execute("crashed_order");
logger.info("orders: goodOrder is {}, badOrder is {},crashedOrder is {}",goodOrder,badOrder,crashedOrder);
}
private Saga createSaga() {
return Saga.create()
.chapter("init an order",10)
.chapter("booking a Fly",10)
.chapter("booking a Hotel",10)
.chapter("withdrawing Money",10);
private static Saga newSaga() {
return Saga
.create()
.chapter("init an order")
.chapter("booking a Fly")
.chapter("booking a Hotel")
.chapter("withdrawing Money");
}
private static ServiceDiscoveryService sd() {
private static ServiceDiscoveryService serviceDiscovery() {
return
new ServiceDiscoveryService()
.discover(new OrderService())

29
saga/src/main/java/com/iluwatar/saga/orchestration/SagaException.java
View File

@ -1,29 +0,0 @@
/*
* The MIT License
* Copyright © 2014-2019 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.saga.orchestration;
public class SagaException extends RuntimeException {
public SagaException(String message) {
super(message);
}
}

141
saga/src/main/java/com/iluwatar/saga/orchestration/SagaOrchestrator.java
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@ -1,30 +1,139 @@
/*
* The MIT License
* Copyright © 2014-2019 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.saga.orchestration;
import java.util.Objects;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.Optional;
import static com.iluwatar.saga.orchestration.Saga.Result.*;
/**
* The orchestrator that manages all the transactions and directs
* the participant services to execute local transactions based on events.
*/
public class SagaOrchestrator {
private ExecutorService executor;
private AtomicBoolean isNormalFlow;
private AtomicBoolean isFinished;
private AtomicInteger currentState;
private static final Logger logger = LoggerFactory.getLogger(SagaOrchestrator.class);
private final Saga saga;
private final ServiceDiscoveryService sd;
private final CurrentState state;
public SagaOrchestrator(Saga saga) {
public SagaOrchestrator(Saga saga, ServiceDiscoveryService sd) {
this.saga = saga;
this.isNormalFlow = new AtomicBoolean(true);
this.isFinished = new AtomicBoolean(false);
this.currentState = new AtomicInteger(0);
this.executor = Executors.newFixedThreadPool(20);
this.sd = sd;
this.state = new CurrentState();
}
public <K> Saga.Result kickOff(K value) {
/**
*
* @param value incoming value
* @param <K> type for incoming value
* @return result @see {@link Saga.Result}
*/
@SuppressWarnings("unchecked")
public <K> Saga.Result execute(K value) {
state.cleanUp();
logger.info(" The new saga is about to start");
Saga.Result result = FINISHED;
K tempVal = value;
while (true) {
int next = state.current();
Saga.Chapter ch = saga.get(next);
Optional<Chapter> srvOpt = sd.find(ch.name);
if (!srvOpt.isPresent()) {
state.directionToBack();
state.back();
continue;
}
Chapter srv = srvOpt.get();
if (state.isForward()) {
ChapterResult processRes = srv.process(tempVal);
if (processRes.isSuccess()) {
next = state.forward();
tempVal = (K) processRes.getValue();
} else {
state.directionToBack();
}
} else {
ChapterResult rlRes = srv.rollback(tempVal);
if (rlRes.isSuccess()) {
next = state.back();
tempVal = (K) rlRes.getValue();
} else {
result = CRASHED;
next = state.back();
}
}
if (!saga.isPresent(next)) {
return state.isForward() ? FINISHED : result == CRASHED ? CRASHED : ROLLBACK;
}
}
}
private static class CurrentState {
int currentNumber;
boolean isForward;
void cleanUp() {
currentNumber = 0;
isForward = true;
}
CurrentState() {
this.currentNumber = 0;
this.isForward = true;
}
boolean isForward() {
return isForward;
}
void directionToBack() {
isForward = false;
}
int forward() {
return ++currentNumber;
}
int back() {
return --currentNumber;
}
int current() {
return currentNumber;
}
}
}

42
saga/src/main/java/com/iluwatar/saga/orchestration/Service.java
View File

@ -1,12 +1,37 @@
/*
* The MIT License
* Copyright © 2014-2019 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.saga.orchestration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import static com.iluwatar.saga.orchestration.Utility.sleepInSec;
/**
* Common abstraction class representing services
* implementing a general contract @see {@link Chapter}
* @param <K> type of incoming param
*/
public abstract class Service<K> implements Chapter<K> {
private static final Logger logger = LoggerFactory.getLogger(Service.class);
protected static final Logger logger = LoggerFactory.getLogger(Service.class);
@Override
public abstract String getName();
@ -14,18 +39,15 @@ public abstract class Service<K> implements Chapter<K> {
@Override
public ChapterResult<K> process(K value) {
logger.info("The chapter about {} is starting", getName());
logger.info("storing or calculating a data {} to db", value);
sleepInSec(1);
logger.info("the data {} has been stored or calculated successfully", value);
logger.info("The chapter '{}' has been started. The data {} has been stored or calculated successfully",
getName(),value);
return ChapterResult.success(value);
}
@Override
public ChapterResult<K> rollback(K value) {
logger.info("Something is going wrong hence The chapter about {} is starting the rollback procedure", getName());
sleepInSec(1);
logger.info("the data {} has been rollbacked successfully", value);
logger.info("The Rollback for a chapter '{}' has been started. The data {} has been rollbacked successfully",
getName(),value);
return ChapterResult.success(value);
}

5
saga/src/main/java/com/iluwatar/saga/orchestration/ServiceDiscoveryService.java
View File

@ -26,10 +26,13 @@ import java.util.HashMap;
import java.util.Map;
import java.util.Optional;
/**
* The class representing a service discovery pattern.
*/
public class ServiceDiscoveryService {
private Map<String, Chapter<?>> services;
public Optional<Chapter<?>> find(String service) {
public Optional<Chapter> find(String service) {
return Optional.ofNullable(services.getOrDefault(service, null));
}

16
saga/src/main/java/com/iluwatar/saga/orchestration/Utility.java
View File

@ -1,16 +0,0 @@
package com.iluwatar.saga.orchestration;
public class Utility {
private Utility() {
}
public static void sleepInSec(int sec){
try {
Thread.sleep(sec*1000);
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
}
}
}

30
saga/src/main/java/com/iluwatar/saga/orchestration/WithdrawMoneyService.java
View File

@ -1,5 +1,30 @@
/*
* The MIT License
* Copyright © 2014-2019 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.saga.orchestration;
/**
* Class representing a service to withdraw a money
*/
public class WithdrawMoneyService extends Service<String> {
@Override
public String getName() {
@ -8,7 +33,10 @@ public class WithdrawMoneyService extends Service<String> {
@Override
public ChapterResult<String> process(String value) {
if(value.equals("no-money")){
if (value.equals("bad_order") || value.equals("crashed_order")) {
logger.info("The chapter '{}' has been started. But the exception has been raised." +
"The rollback is about to start",
getName(), value);
return ChapterResult.failure(value);
}
return super.process(value);

13
saga/src/test/java/com/iluwatar/saga/orchestration/SagaApplicationTest.java Normal file
View File

@ -0,0 +1,13 @@
package com.iluwatar.saga.orchestration;
import org.junit.Test;
import static org.junit.Assert.*;
public class SagaApplicationTest {
@Test
public void mainTest() {
SagaApplication.main(new String[]{});
}
}

117
saga/src/test/java/com/iluwatar/saga/orchestration/SagaOrchestratorInternallyTest.java Normal file
View File

@ -0,0 +1,117 @@
package com.iluwatar.saga.orchestration;
import org.junit.Assert;
import org.junit.Test;
import java.util.ArrayList;
import java.util.List;
public class SagaOrchestratorInternallyTest {
private List<String> records = new ArrayList<>();
@Test
public void execute() {
SagaOrchestrator sagaOrchestrator = new SagaOrchestrator(newSaga(), serviceDiscovery());
Saga.Result result = sagaOrchestrator.execute(1);
Assert.assertEquals(result, Saga.Result.ROLLBACK);
Assert.assertArrayEquals(
records.toArray(new String[]{}),
new String[]{"+1","+2","+3","+4","-4","-3","-2","-1"});
}
private static Saga newSaga() {
return Saga
.create()
.chapter("1")
.chapter("2")
.chapter("3")
.chapter("4");
}
private ServiceDiscoveryService serviceDiscovery() {
return
new ServiceDiscoveryService()
.discover(new Service1())
.discover(new Service2())
.discover(new Service3())
.discover(new Service4());
}
class Service1 extends Service<Integer> {
@Override
public String getName() {
return "1";
}
@Override
public ChapterResult<Integer> process(Integer value) {
records.add("+1");
return ChapterResult.success(value);
}
@Override
public ChapterResult<Integer> rollback(Integer value) {
records.add("-1");
return ChapterResult.success(value);
}
}
class Service2 extends Service<Integer> {
@Override
public String getName() {
return "2";
}
@Override
public ChapterResult<Integer> process(Integer value) {
records.add("+2");
return ChapterResult.success(value);
}
@Override
public ChapterResult<Integer> rollback(Integer value) {
records.add("-2");
return ChapterResult.success(value);
}
}
class Service3 extends Service<Integer> {
@Override
public String getName() {
return "3";
}
@Override
public ChapterResult<Integer> process(Integer value) {
records.add("+3");
return ChapterResult.success(value);
}
@Override
public ChapterResult<Integer> rollback(Integer value) {
records.add("-3");
return ChapterResult.success(value);
}
}
class Service4 extends Service<Integer> {
@Override
public String getName() {
return "4";
}
@Override
public ChapterResult<Integer> process(Integer value) {
records.add("+4");
return ChapterResult.failure(value);
}
@Override
public ChapterResult<Integer> rollback(Integer value) {
records.add("-4");
return ChapterResult.success(value);
}
}
}

37
saga/src/test/java/com/iluwatar/saga/orchestration/SagaOrchestratorTest.java Normal file
View File

@ -0,0 +1,37 @@
package com.iluwatar.saga.orchestration;
import org.junit.Assert;
import org.junit.Test;
import static org.junit.Assert.*;
public class SagaOrchestratorTest {
@Test
public void execute() {
SagaOrchestrator sagaOrchestrator = new SagaOrchestrator(newSaga(), serviceDiscovery());
Saga.Result badOrder = sagaOrchestrator.execute("bad_order");
Saga.Result crashedOrder = sagaOrchestrator.execute("crashed_order");
Assert.assertEquals(badOrder, Saga.Result.ROLLBACK);
Assert.assertEquals(crashedOrder, Saga.Result.CRASHED);
}
private static Saga newSaga() {
return Saga
.create()
.chapter("init an order")
.chapter("booking a Fly")
.chapter("booking a Hotel")
.chapter("withdrawing Money");
}
private static ServiceDiscoveryService serviceDiscovery() {
return
new ServiceDiscoveryService()
.discover(new OrderService())
.discover(new FlyBookingService())
.discover(new HotelBookingService())
.discover(new WithdrawMoneyService());
}
}