diff --git a/commander/src/test/java/com/iluwatar/commander/CommanderTest.java b/commander/src/test/java/com/iluwatar/commander/CommanderTest.java
index 76884deac..717b68200 100644
--- a/commander/src/test/java/com/iluwatar/commander/CommanderTest.java
+++ b/commander/src/test/java/com/iluwatar/commander/CommanderTest.java
@@ -1,106 +1,606 @@
+/*
+ * The MIT License
+ * Copyright © 2014-2021 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.commander;
-import com.iluwatar.commander.employeehandle.EmployeeDatabase;
+import com.iluwatar.commander.Order.MessageSent;
+import com.iluwatar.commander.Order.PaymentStatus;
import com.iluwatar.commander.employeehandle.EmployeeHandle;
import com.iluwatar.commander.exceptions.DatabaseUnavailableException;
-import com.iluwatar.commander.messagingservice.MessagingDatabase;
+import com.iluwatar.commander.exceptions.ItemUnavailableException;
+import com.iluwatar.commander.exceptions.PaymentDetailsErrorException;
+import com.iluwatar.commander.exceptions.ShippingNotPossibleException;
import com.iluwatar.commander.messagingservice.MessagingService;
-import com.iluwatar.commander.paymentservice.PaymentDatabase;
import com.iluwatar.commander.paymentservice.PaymentService;
import com.iluwatar.commander.queue.QueueDatabase;
-import com.iluwatar.commander.shippingservice.ShippingDatabase;
+import com.iluwatar.commander.queue.QueueTask;
+import com.iluwatar.commander.queue.QueueTask.TaskType;
import com.iluwatar.commander.shippingservice.ShippingService;
+import java.util.List;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
-import org.junit.jupiter.api.Test;
-import org.junit.platform.commons.util.StringUtils;
-import static org.junit.jupiter.api.Assertions.assertFalse;
+/**
+ * Commander pattern is used to handle all issues that can come up while making a
+ * distributed transaction. The idea is to have a commander, which coordinates the execution of all
+ * instructions and ensures proper completion using retries and taking care of idempotence. By
+ * queueing instructions while they haven't been done, we can ensure a state of 'eventual
+ * consistency'.
+ * In our example, we have an e-commerce application. When the user places an order,
+ * the shipping service is intimated first. If the service does not respond for some reason, the
+ * order is not placed. If response is received, the commander then calls for the payment service to
+ * be intimated. If this fails, the shipping still takes place (order converted to COD) and the item
+ * is queued. If the queue is also found to be unavailable, the payment is noted to be not done and
+ * this is added to an employee database. Three types of messages are sent to the user - one, if
+ * payment succeeds; two, if payment fails definitively; and three, if payment fails in the first
+ * attempt. If the message is not sent, this is also queued and is added to employee db. We also
+ * have a time limit for each instruction to be completed, after which, the instruction is not
+ * executed, thereby ensuring that resources are not held for too long. In the rare occasion in
+ * which everything fails, an individual would have to step in to figure out how to solve the
+ * issue.
+ * We have abstract classes {@link Database} and {@link Service} which are extended
+ * by all the databases and services. Each service has a database to be updated, and receives
+ * request from an outside user (the {@link Commander} class here). There are 5 microservices -
+ * {@link ShippingService}, {@link PaymentService}, {@link MessagingService}, {@link EmployeeHandle}
+ * and a {@link QueueDatabase}. We use retries to execute any instruction using {@link Retry} class,
+ * and idempotence is ensured by going through some checks before making requests to services and
+ * making change in {@link Order} class fields if request succeeds or definitively fails. There are
+ * 5 classes - {@link AppShippingFailCases}, {@link AppPaymentFailCases}, {@link
+ * AppMessagingFailCases}, {@link AppQueueFailCases} and {@link AppEmployeeDbFailCases}, which look
+ * at the different scenarios that may be encountered during the placing of an order.
+ */
-class CommanderTest {
+public class Commander {
- private final int numOfRetries = 1;
- private final long retryDuration = 10_000;
- private final long queueTime = 1_000;
- private final long queueTaskTime = 10_000;
- private final long paymentTime = 60_000;
- private final long messageTime = 50_000;
- private final long employeeTime = 20_000;
+ private final QueueDatabase queue;
+ private final EmployeeHandle employeeDb;
+ private final PaymentService paymentService;
+ private final ShippingService shippingService;
+ private final MessagingService messagingService;
+ private int queueItems = 0; //keeping track here only so don't need access to queue db to get this
+ private final int numOfRetries;
+ private final long retryDuration;
+ private final long queueTime;
+ private final long queueTaskTime;
+ private final long paymentTime;
+ private final long messageTime;
+ private final long employeeTime;
+ private boolean finalSiteMsgShown;
+ private static final Logger LOG = LoggerFactory.getLogger(Commander.class);
+ //we could also have another db where it stores all orders
- private Commander buildCommanderObject() {
- PaymentService paymentService = new PaymentService
- (new PaymentDatabase(), new DatabaseUnavailableException(),
- new DatabaseUnavailableException(), new DatabaseUnavailableException(),
- new DatabaseUnavailableException(), new DatabaseUnavailableException(),
- new DatabaseUnavailableException());
- var shippingService = new ShippingService(new ShippingDatabase());
- var messagingService = new MessagingService(new MessagingDatabase());
- var employeeHandle = new EmployeeHandle
- (new EmployeeDatabase(), new DatabaseUnavailableException(),
- new DatabaseUnavailableException(), new DatabaseUnavailableException(),
- new DatabaseUnavailableException(), new DatabaseUnavailableException(),
- new DatabaseUnavailableException());
- var qdb = new QueueDatabase
- (new DatabaseUnavailableException(), new DatabaseUnavailableException(),
- new DatabaseUnavailableException(), new DatabaseUnavailableException(),
- new DatabaseUnavailableException(), new DatabaseUnavailableException());
- return new Commander(employeeHandle, paymentService, shippingService,
- messagingService, qdb, numOfRetries, retryDuration,
- queueTime, queueTaskTime, paymentTime, messageTime, employeeTime);
+ private static final String ORDER_ID = "Order {}";
+ private static final String REQUEST_ID = " request Id: {}";
+ private static final String ERROR_CONNECTING_MSG_SVC =
+ ": Error in connecting to messaging service ";
+ private static final String TRY_CONNECTING_MSG_SVC =
+ ": Trying to connect to messaging service..";
+
+ Commander(EmployeeHandle empDb, PaymentService paymentService, ShippingService shippingService,
+ MessagingService messagingService, QueueDatabase qdb, int numOfRetries,
+ long retryDuration, long queueTime, long queueTaskTime, long paymentTime,
+ long messageTime, long employeeTime) {
+ this.paymentService = paymentService;
+ this.shippingService = shippingService;
+ this.messagingService = messagingService;
+ this.employeeDb = empDb;
+ this.queue = qdb;
+ this.numOfRetries = numOfRetries;
+ this.retryDuration = retryDuration;
+ this.queueTime = queueTime;
+ this.queueTaskTime = queueTaskTime;
+ this.paymentTime = paymentTime;
+ this.messageTime = messageTime;
+ this.employeeTime = employeeTime;
+ this.finalSiteMsgShown = false;
}
- private Commander buildCommanderObjectWithoutPaymentDB() {
- return buildCommanderObjectWithoutPaymentDB(false);
+ void placeOrder(Order order) throws Exception {
+ sendShippingRequest(order);
}
- private Commander buildCommanderObjectWithoutPaymentDB(boolean includeException) {
- var l = new DatabaseUnavailableException();
- PaymentService paymentService;
- ShippingService shippingService;
- MessagingService messagingService;
- EmployeeHandle employeeHandle;
- if (includeException) {
- paymentService = new PaymentService
- (null, l);
- shippingService = new ShippingService(null, l);
- messagingService = new MessagingService(null, l);
- employeeHandle = new EmployeeHandle
- (null, l);
- } else {
- paymentService = new PaymentService
- (null);
- shippingService = new ShippingService(null);
- messagingService = new MessagingService(null);
- employeeHandle = new EmployeeHandle
- (null);
+ private void sendShippingRequest(Order order) throws Exception {
+ var list = shippingService.exceptionsList;
+ Retry.Operation op = (l) -> {
+ if (!l.isEmpty()) {
+ if (DatabaseUnavailableException.class.isAssignableFrom(l.get(0).getClass())) {
+ LOG.debug(ORDER_ID + ": Error in connecting to shipping service, "
+ + "trying again..", order.id);
+ } else {
+ LOG.debug(ORDER_ID + ": Error in creating shipping request..", order.id);
+ }
+ throw l.remove(0);
+ }
+ String transactionId = shippingService.receiveRequest(order.item, order.user.address);
+ //could save this transaction id in a db too
+ LOG.info(ORDER_ID + ": Shipping placed successfully, transaction id: {}",
+ order.id, transactionId);
+ LOG.info("Order has been placed and will be shipped to you. Please wait while we make your"
+ + " payment... ");
+ sendPaymentRequest(order);
+ };
+ Retry.HandleErrorIssue handleError = (o, err) -> {
+ if (ShippingNotPossibleException.class.isAssignableFrom(err.getClass())) {
+ LOG.info("Shipping is currently not possible to your address. We are working on the problem"
+ + " and will get back to you asap.");
+ finalSiteMsgShown = true;
+ LOG.info(ORDER_ID + ": Shipping not possible to address, trying to add problem "
+ + "to employee db..", order.id);
+ employeeHandleIssue(o);
+ } else if (ItemUnavailableException.class.isAssignableFrom(err.getClass())) {
+ LOG.info("This item is currently unavailable. We will inform you as soon as the item "
+ + "becomes available again.");
+ finalSiteMsgShown = true;
+ LOG.info(ORDER_ID + ": Item {}" + " unavailable, trying to add "
+ + "problem to employee handle..", order.id, order.item);
+ employeeHandleIssue(o);
+ } else {
+ LOG.info("Sorry, there was a problem in creating your order. Please try later.");
+ LOG.error(ORDER_ID + ": Shipping service unavailable, order not placed..", order.id);
+ finalSiteMsgShown = true;
+ }
+ };
+ var r = new Retry<>(op, handleError, numOfRetries, retryDuration,
+ e -> DatabaseUnavailableException.class.isAssignableFrom(e.getClass()));
+ r.perform(list, order);
+ }
+
+ private void sendPaymentRequest(Order order) {
+ if (System.currentTimeMillis() - order.createdTime >= this.paymentTime) {
+ if (order.paid.equals(PaymentStatus.TRYING)) {
+ order.paid = PaymentStatus.NOT_DONE;
+ sendPaymentFailureMessage(order);
+ LOG.error(ORDER_ID + ": Payment time for order over, failed and returning..", order.id);
+ } //if succeeded or failed, would have been dequeued, no attempt to make payment
+ return;
}
-
-
- return new Commander(employeeHandle, paymentService, shippingService,
- messagingService, null, numOfRetries, retryDuration,
- queueTime, queueTaskTime, paymentTime, messageTime, employeeTime);
+ var list = paymentService.exceptionsList;
+ var t = new Thread(() -> {
+ Retry.Operation op = (l) -> {
+ if (!l.isEmpty()) {
+ if (DatabaseUnavailableException.class.isAssignableFrom(l.get(0).getClass())) {
+ LOG.debug(ORDER_ID + ": Error in connecting to payment service,"
+ + " trying again..", order.id);
+ } else {
+ LOG.debug(ORDER_ID + ": Error in creating payment request..", order.id);
+ }
+ throw l.remove(0);
+ }
+ if (order.paid.equals(PaymentStatus.TRYING)) {
+ var transactionId = paymentService.receiveRequest(order.price);
+ order.paid = PaymentStatus.DONE;
+ LOG.info(ORDER_ID + ": Payment successful, transaction Id: {}",
+ order.id, transactionId);
+ if (!finalSiteMsgShown) {
+ LOG.info("Payment made successfully, thank you for shopping with us!!");
+ finalSiteMsgShown = true;
+ }
+ sendSuccessMessage(order);
+ }
+ };
+ Retry.HandleErrorIssue handleError = (o, err) -> {
+ if (PaymentDetailsErrorException.class.isAssignableFrom(err.getClass())) {
+ if (!finalSiteMsgShown) {
+ LOG.info("There was an error in payment. Your account/card details "
+ + "may have been incorrect. "
+ + "Meanwhile, your order has been converted to COD and will be shipped.");
+ finalSiteMsgShown = true;
+ }
+ LOG.error(ORDER_ID + ": Payment details incorrect, failed..", order.id);
+ o.paid = PaymentStatus.NOT_DONE;
+ sendPaymentFailureMessage(o);
+ } else {
+ if (o.messageSent.equals(MessageSent.NONE_SENT)) {
+ if (!finalSiteMsgShown) {
+ LOG.info("There was an error in payment. We are on it, and will get back to you "
+ + "asap. Don't worry, your order has been placed and will be shipped.");
+ finalSiteMsgShown = true;
+ }
+ LOG.warn(ORDER_ID + ": Payment error, going to queue..", order.id);
+ sendPaymentPossibleErrorMsg(o);
+ }
+ if (o.paid.equals(PaymentStatus.TRYING) && System
+ .currentTimeMillis() - o.createdTime < paymentTime) {
+ var qt = new QueueTask(o, TaskType.PAYMENT, -1);
+ updateQueue(qt);
+ }
+ }
+ };
+ var r = new Retry<>(op, handleError, numOfRetries, retryDuration,
+ e -> DatabaseUnavailableException.class.isAssignableFrom(e.getClass()));
+ try {
+ r.perform(list, order);
+ } catch (Exception e1) {
+ e1.printStackTrace();
+ }
+ });
+ t.start();
}
- @Test
- void testPlaceOrder() throws Exception {
- Commander c = buildCommanderObject();
- var order = new Order(new User("K", "J"), "pen", 1f);
- c.placeOrder(order);
- assertFalse(StringUtils.isBlank(order.id));
+ private void updateQueue(QueueTask qt) {
+ if (System.currentTimeMillis() - qt.order.createdTime >= this.queueTime) {
+ // since payment time is lesser than queuetime it would have already failed..
+ // additional check not needed
+ LOG.trace(ORDER_ID + ": Queue time for order over, failed..", qt.order.id);
+ return;
+ } else if (qt.taskType.equals(TaskType.PAYMENT) && !qt.order.paid.equals(PaymentStatus.TRYING)
+ || qt.taskType.equals(TaskType.MESSAGING) && (qt.messageType == 1
+ && !qt.order.messageSent.equals(MessageSent.NONE_SENT)
+ || qt.order.messageSent.equals(MessageSent.PAYMENT_FAIL)
+ || qt.order.messageSent.equals(MessageSent.PAYMENT_SUCCESSFUL))
+ || qt.taskType.equals(TaskType.EMPLOYEE_DB) && qt.order.addedToEmployeeHandle) {
+ LOG.trace(ORDER_ID + ": Not queueing task since task already done..", qt.order.id);
+ return;
+ }
+ var list = queue.exceptionsList;
+ Thread t = new Thread(() -> {
+ Retry.Operation op = (list1) -> {
+ if (!list1.isEmpty()) {
+ LOG.warn(ORDER_ID + ": Error in connecting to queue db, trying again..", qt.order.id);
+ throw list1.remove(0);
+ }
+ queue.add(qt);
+ queueItems++;
+ LOG.info(ORDER_ID + ": {}" + " task enqueued..", qt.order.id, qt.getType());
+ tryDoingTasksInQueue();
+ };
+ Retry.HandleErrorIssue handleError = (qt1, err) -> {
+ if (qt1.taskType.equals(TaskType.PAYMENT)) {
+ qt1.order.paid = PaymentStatus.NOT_DONE;
+ sendPaymentFailureMessage(qt1.order);
+ LOG.error(ORDER_ID + ": Unable to enqueue payment task,"
+ + " payment failed..", qt1.order.id);
+ }
+ LOG.error(ORDER_ID + ": Unable to enqueue task of type {}"
+ + ", trying to add to employee handle..", qt1.order.id, qt1.getType());
+ employeeHandleIssue(qt1.order);
+ };
+ var r = new Retry<>(op, handleError, numOfRetries, retryDuration,
+ e -> DatabaseUnavailableException.class.isAssignableFrom(e.getClass()));
+ try {
+ r.perform(list, qt);
+ } catch (Exception e1) {
+ e1.printStackTrace();
+ }
+ });
+ t.start();
}
- @Test
- void testPlaceOrderWithServiceException() throws Exception {
- Commander c = buildCommanderObjectWithoutPaymentDB();
- var order = new Order(new User("K", null), "pen", 1f);
- c.placeOrder(order);
- assertFalse(StringUtils.isBlank(order.id));
+ private void tryDoingTasksInQueue() { //commander controls operations done to queue
+ var list = queue.exceptionsList;
+ var t2 = new Thread(() -> {
+ Retry.Operation op = (list1) -> {
+ if (!list1.isEmpty()) {
+ LOG.warn("Error in accessing queue db to do tasks, trying again..");
+ throw list1.remove(0);
+ }
+ doTasksInQueue();
+ };
+ Retry.HandleErrorIssue handleError = (o, err) -> {
+ };
+ var r = new Retry<>(op, handleError, numOfRetries, retryDuration,
+ e -> DatabaseUnavailableException.class.isAssignableFrom(e.getClass()));
+ try {
+ r.perform(list, null);
+ } catch (Exception e1) {
+ e1.printStackTrace();
+ }
+ });
+ t2.start();
}
- @Test
- void testPlaceOrderWithServiceExceptionAndList() throws Exception {
- Commander c = buildCommanderObjectWithoutPaymentDB(true);
- var order = new Order(new User("K", null), "pen", 1f);
- c.placeOrder(order);
- assertFalse(StringUtils.isBlank(order.id));
+ private void tryDequeue() {
+ var list = queue.exceptionsList;
+ var t3 = new Thread(() -> {
+ Retry.Operation op = (list1) -> {
+ if (!list1.isEmpty()) {
+ LOG.warn("Error in accessing queue db to dequeue task, trying again..");
+ throw list1.remove(0);
+ }
+ queue.dequeue();
+ queueItems--;
+ };
+ Retry.HandleErrorIssue handleError = (o, err) -> {
+ };
+ var r = new Retry(op, handleError, numOfRetries, retryDuration,
+ e -> DatabaseUnavailableException.class.isAssignableFrom(e.getClass()));
+ try {
+ r.perform(list, null);
+ } catch (Exception e1) {
+ e1.printStackTrace();
+ }
+ });
+ t3.start();
}
+
+ private void sendSuccessMessage(Order order) {
+ if (System.currentTimeMillis() - order.createdTime >= this.messageTime) {
+ LOG.trace(ORDER_ID + ": Message time for order over, returning..", order.id);
+ return;
+ }
+ var list = messagingService.exceptionsList;
+ Thread t = new Thread(() -> {
+ Retry.Operation op = handleSuccessMessageRetryOperation(order);
+ Retry.HandleErrorIssue handleError = (o, err) -> {
+ handleSuccessMessageErrorIssue(order, o);
+ };
+ var r = new Retry<>(op, handleError, numOfRetries, retryDuration,
+ e -> DatabaseUnavailableException.class.isAssignableFrom(e.getClass()));
+ try {
+ r.perform(list, order);
+ } catch (Exception e1) {
+ e1.printStackTrace();
+ }
+ });
+ t.start();
+ }
+
+ private void handleSuccessMessageErrorIssue(Order order, Order o) {
+ if ((o.messageSent.equals(MessageSent.NONE_SENT) || o.messageSent
+ .equals(MessageSent.PAYMENT_TRYING))
+ && System.currentTimeMillis() - o.createdTime < messageTime) {
+ var qt = new QueueTask(order, TaskType.MESSAGING, 2);
+ updateQueue(qt);
+ LOG.info(ORDER_ID + ": Error in sending Payment Success message, trying to"
+ + " queue task and add to employee handle..", order.id);
+ employeeHandleIssue(order);
+ }
+ }
+
+ private Retry.Operation handleSuccessMessageRetryOperation(Order order) {
+ return (l) -> {
+ if (!l.isEmpty()) {
+ if (DatabaseUnavailableException.class.isAssignableFrom(l.get(0).getClass())) {
+ LOG.debug(ORDER_ID + ERROR_CONNECTING_MSG_SVC
+ + "(Payment Success msg), trying again..", order.id);
+ } else {
+ LOG.debug(ORDER_ID + ": Error in creating Payment Success"
+ + " messaging request..", order.id);
+ }
+ throw l.remove(0);
+ }
+ if (!order.messageSent.equals(MessageSent.PAYMENT_FAIL)
+ && !order.messageSent.equals(MessageSent.PAYMENT_SUCCESSFUL)) {
+ var requestId = messagingService.receiveRequest(2);
+ order.messageSent = MessageSent.PAYMENT_SUCCESSFUL;
+ LOG.info(ORDER_ID + ": Payment Success message sent,"
+ + REQUEST_ID, order.id, requestId);
+ }
+ };
+ }
+
+ private void sendPaymentFailureMessage(Order order) {
+ if (System.currentTimeMillis() - order.createdTime >= this.messageTime) {
+ LOG.trace(ORDER_ID + ": Message time for order over, returning..", order.id);
+ return;
+ }
+ var list = messagingService.exceptionsList;
+ var t = new Thread(() -> {
+ Retry.Operation op = (l) -> {
+ handlePaymentFailureRetryOperation(order, l);
+ };
+ Retry.HandleErrorIssue handleError = (o, err) -> {
+ handlePaymentErrorIssue(order, o);
+ };
+ var r = new Retry<>(op, handleError, numOfRetries, retryDuration,
+ e -> DatabaseUnavailableException.class.isAssignableFrom(e.getClass()));
+ try {
+ r.perform(list, order);
+ } catch (Exception e1) {
+ e1.printStackTrace();
+ }
+ });
+ t.start();
+ }
+
+ private void handlePaymentErrorIssue(Order order, Order o) {
+ if ((o.messageSent.equals(MessageSent.NONE_SENT) || o.messageSent
+ .equals(MessageSent.PAYMENT_TRYING))
+ && System.currentTimeMillis() - o.createdTime < messageTime) {
+ var qt = new QueueTask(order, TaskType.MESSAGING, 0);
+ updateQueue(qt);
+ LOG.warn(ORDER_ID + ": Error in sending Payment Failure message, "
+ + "trying to queue task and add to employee handle..", order.id);
+ employeeHandleIssue(o);
+ }
+ }
+
+ private void handlePaymentFailureRetryOperation(Order order, List l) throws Exception {
+ if (!l.isEmpty()) {
+ if (DatabaseUnavailableException.class.isAssignableFrom(l.get(0).getClass())) {
+ LOG.debug(ORDER_ID + ERROR_CONNECTING_MSG_SVC
+ + "(Payment Failure msg), trying again..", order.id);
+ } else {
+ LOG.debug(ORDER_ID + ": Error in creating Payment Failure"
+ + " message request..", order.id);
+ }
+ throw l.remove(0);
+ }
+ if (!order.messageSent.equals(MessageSent.PAYMENT_FAIL)
+ && !order.messageSent.equals(MessageSent.PAYMENT_SUCCESSFUL)) {
+ var requestId = messagingService.receiveRequest(0);
+ order.messageSent = MessageSent.PAYMENT_FAIL;
+ LOG.info(ORDER_ID + ": Payment Failure message sent successfully,"
+ + REQUEST_ID, order.id, requestId);
+ }
+ }
+
+ private void sendPaymentPossibleErrorMsg(Order order) {
+ if (System.currentTimeMillis() - order.createdTime >= this.messageTime) {
+ LOG.trace("Message time for order over, returning..");
+ return;
+ }
+ var list = messagingService.exceptionsList;
+ var t = new Thread(() -> {
+ Retry.Operation op = (l) -> {
+ handlePaymentPossibleErrorMsgRetryOperation(order, l);
+ };
+ Retry.HandleErrorIssue handleError = (o, err) -> {
+ handlePaymentPossibleErrorMsgErrorIssue(order, o);
+ };
+ var r = new Retry<>(op, handleError, numOfRetries, retryDuration,
+ e -> DatabaseUnavailableException.class.isAssignableFrom(e.getClass()));
+ try {
+ r.perform(list, order);
+ } catch (Exception e1) {
+ e1.printStackTrace();
+ }
+ });
+ t.start();
+ }
+
+ private void handlePaymentPossibleErrorMsgErrorIssue(Order order, Order o) {
+ if (o.messageSent.equals(MessageSent.NONE_SENT) && order.paid
+ .equals(PaymentStatus.TRYING)
+ && System.currentTimeMillis() - o.createdTime < messageTime) {
+ var qt = new QueueTask(order, TaskType.MESSAGING, 1);
+ updateQueue(qt);
+ LOG.warn(ORDER_ID + ": Error in sending Payment Error message, "
+ + "trying to queue task and add to employee handle..", order.id);
+ employeeHandleIssue(o);
+ }
+ }
+
+ private void handlePaymentPossibleErrorMsgRetryOperation(Order order, List l)
+ throws Exception {
+ if (!l.isEmpty()) {
+ if (DatabaseUnavailableException.class.isAssignableFrom(l.get(0).getClass())) {
+ LOG.debug(ORDER_ID + ERROR_CONNECTING_MSG_SVC
+ + "(Payment Error msg), trying again..", order.id);
+ } else {
+ LOG.debug(ORDER_ID + ": Error in creating Payment Error"
+ + " messaging request..", order.id);
+ }
+ throw l.remove(0);
+ }
+ if (order.paid.equals(PaymentStatus.TRYING) && order.messageSent
+ .equals(MessageSent.NONE_SENT)) {
+ var requestId = messagingService.receiveRequest(1);
+ order.messageSent = MessageSent.PAYMENT_TRYING;
+ LOG.info(ORDER_ID + ": Payment Error message sent successfully,"
+ + REQUEST_ID, order.id, requestId);
+ }
+ }
+
+ private void employeeHandleIssue(Order order) {
+ if (System.currentTimeMillis() - order.createdTime >= this.employeeTime) {
+ LOG.trace(ORDER_ID + ": Employee handle time for order over, returning..", order.id);
+ return;
+ }
+ var list = employeeDb.exceptionsList;
+ var t = new Thread(() -> {
+ Retry.Operation op = (l) -> {
+ if (!l.isEmpty()) {
+ LOG.warn(ORDER_ID + ": Error in connecting to employee handle,"
+ + " trying again..", order.id);
+ throw l.remove(0);
+ }
+ if (!order.addedToEmployeeHandle) {
+ employeeDb.receiveRequest(order);
+ order.addedToEmployeeHandle = true;
+ LOG.info(ORDER_ID + ": Added order to employee database", order.id);
+ }
+ };
+ Retry.HandleErrorIssue handleError = (o, err) -> {
+ if (!o.addedToEmployeeHandle && System
+ .currentTimeMillis() - order.createdTime < employeeTime) {
+ var qt = new QueueTask(order, TaskType.EMPLOYEE_DB, -1);
+ updateQueue(qt);
+ LOG.warn(ORDER_ID + ": Error in adding to employee db,"
+ + " trying to queue task..", order.id);
+ }
+ };
+ var r = new Retry<>(op, handleError, numOfRetries, retryDuration,
+ e -> DatabaseUnavailableException.class.isAssignableFrom(e.getClass()));
+ try {
+ r.perform(list, order);
+ } catch (Exception e1) {
+ e1.printStackTrace();
+ }
+ });
+ t.start();
+ }
+
+ private void doTasksInQueue() throws Exception {
+ if (queueItems != 0) {
+ var qt = queue.peek(); //this should probably be cloned here
+ //this is why we have retry for doTasksInQueue
+ LOG.trace(ORDER_ID + ": Started doing task of type {}", qt.order.id, qt.getType());
+ if (qt.getFirstAttemptTime() == -1) {
+ qt.setFirstAttemptTime(System.currentTimeMillis());
+ }
+ if (System.currentTimeMillis() - qt.getFirstAttemptTime() >= queueTaskTime) {
+ tryDequeue();
+ LOG.trace(ORDER_ID + ": This queue task of type {}"
+ + " does not need to be done anymore (timeout), dequeue..", qt.order.id, qt.getType());
+ } else {
+ if (qt.taskType.equals(TaskType.PAYMENT)) {
+ if (!qt.order.paid.equals(PaymentStatus.TRYING)) {
+ tryDequeue();
+ LOG.trace(ORDER_ID + ": This payment task already done, dequeueing..", qt.order.id);
+ } else {
+ sendPaymentRequest(qt.order);
+ LOG.debug(ORDER_ID + ": Trying to connect to payment service..", qt.order.id);
+ }
+ } else if (qt.taskType.equals(TaskType.MESSAGING)) {
+ if (qt.order.messageSent.equals(MessageSent.PAYMENT_FAIL)
+ || qt.order.messageSent.equals(MessageSent.PAYMENT_SUCCESSFUL)) {
+ tryDequeue();
+ LOG.trace(ORDER_ID + ": This messaging task already done, dequeue..", qt.order.id);
+ } else if (qt.messageType == 1 && (!qt.order.messageSent.equals(MessageSent.NONE_SENT)
+ || !qt.order.paid.equals(PaymentStatus.TRYING))) {
+ tryDequeue();
+ LOG.trace(ORDER_ID + ": This messaging task does not need to be done,"
+ + " dequeue..", qt.order.id);
+ } else if (qt.messageType == 0) {
+ sendPaymentFailureMessage(qt.order);
+ LOG.debug(ORDER_ID + TRY_CONNECTING_MSG_SVC, qt.order.id);
+ } else if (qt.messageType == 1) {
+ sendPaymentPossibleErrorMsg(qt.order);
+ LOG.debug(ORDER_ID + TRY_CONNECTING_MSG_SVC, qt.order.id);
+ } else if (qt.messageType == 2) {
+ sendSuccessMessage(qt.order);
+ LOG.debug(ORDER_ID + TRY_CONNECTING_MSG_SVC, qt.order.id);
+ }
+ } else if (qt.taskType.equals(TaskType.EMPLOYEE_DB)) {
+ if (qt.order.addedToEmployeeHandle) {
+ tryDequeue();
+ LOG.trace(ORDER_ID + ": This employee handle task already done,"
+ + " dequeue..", qt.order.id);
+ } else {
+ employeeHandleIssue(qt.order);
+ LOG.debug(ORDER_ID + ": Trying to connect to employee handle..", qt.order.id);
+ }
+ }
+ }
+ }
+ if (queueItems == 0) {
+ LOG.trace("Queue is empty, returning..");
+ } else {
+ Thread.sleep(queueTaskTime / 3);
+ tryDoingTasksInQueue();
+ }
+ }
+
}