Mule自带例子之flight-reservation

1 配置效果图

2 应用的配置文件

 <?xml version="1.0" encoding="UTF-8"?>

 <mule xmlns:scripting="http://www.mulesoft.org/schema/mule/scripting" xmlns:vm="http://www.mulesoft.org/schema/mule/vm" xmlns:json="http://www.mulesoft.org/schema/mule/json"
     xmlns:ajax="http://www.mulesoft.org/schema/mule/ajax" xmlns="http://www.mulesoft.org/schema/mule/core" xmlns:doc="http://www.mulesoft.org/schema/mule/documentation"
     xmlns:spring="http://www.springframework.org/schema/beans" version="CE-3.4.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-current.xsd
 http://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/current/mule.xsd
 http://www.mulesoft.org/schema/mule/ajax http://www.mulesoft.org/schema/mule/ajax/current/mule-ajax.xsd
 http://www.mulesoft.org/schema/mule/json http://www.mulesoft.org/schema/mule/json/current/mule-json.xsd
 http://www.mulesoft.org/schema/mule/vm http://www.mulesoft.org/schema/mule/vm/current/mule-vm.xsd
 http://www.mulesoft.org/schema/mule/scripting http://www.mulesoft.org/schema/mule/scripting/current/mule-scripting.xsd">

     <ajax:connector name="Ajax" serverUrl="http://0.0.0.0:9092/reservation" resourceBase="${app.home}/docroot" jsonCommented="true"    doc:name="Ajax" />

     <!-- 航班预定流，主要通过调用processReservation来完成航班信息的处理 -->
     <flow name="makeReservation">
         <ajax:inbound-endpoint channel="/searchFlights" connector-ref="Ajax" responseTimeout="10000" doc:name="Ajax" />
         <flow-ref name="processReservation" doc:name="processReservation"/>
     </flow>

     <!--
     航班预定信息处理流
         对航班的安排做的假设：
             航班号以3结尾，不可获得，直接抛出FlightUnavailableException异常
             航班号不是以3结尾，可进入下一步处理：
                 航班号以2结尾，可取得座位信息'20A'；否则抛出没有座位信息异常'No seat info available'，并把'No seat info available'赋给座位信息部分
      -->
     <flow name="processReservation">

         <json:json-to-object-transformer returnClass="org.mule.example.ReservationRequest" doc:name="JSON to ReservationRequest" />    

         <!-- 把请求的负载保存到session对象中（payload的类型为ReservationRequest） -->
         <set-session-variable variableName="reservationRequest" value="#[payload]" doc:name="Save orignal request in Session" />

         <!-- 设置响应消息的负载 -->
         <set-payload value="#[new org.mule.example.ReservationResponse()]" doc:name="Set ReservationResponse Payload" />

         <!-- 把请求消息中的flighs设置到响应消息中 （payload的类型为ReservationResponse） -->
         <expression-component doc:name="Add request flight to response">
             <![CDATA[payload.setFlights(reservationRequest.flights)]]>
         </expression-component>

         <set-variable variableName="totalPrice" value="#[0]" doc:name="Initialize totalPrice" /> <!-- 设置一个totalPrice变量，值为0 -->

         <!-- 迭代处理payload（payload的类型为ReservationResponse，里面有请求信息flights） -->
         <foreach collection="#[payload.flights]" doc:name="Foreach on flights">
             <scripting:transformer doc:name="Search flight availability">
                 <scripting:script engine="Groovy"><![CDATA[
 if (payload.flightNumber.endsWith('3'))
     throw new org.mule.example.FlightUnavailableException()
 else
     payload]]>
                 </scripting:script>
             </scripting:transformer>

             <!--
             此处声明了一个地址为vm://acquireFlightPriceQueue VM出站端点，即把响应消息扔到了acquireSeatsInfoQueue队列
             而acquireSeatsInfo流，在地址vm://acquireFlightPriceQueue上等待请求
             exchange-pattern="request-response" 表示该VM出站端点 等待acquireSeatsInfo流给的响应
             -->
             <vm:outbound-endpoint exchange-pattern="request-response" path="acquireSeatsInfoQueue" doc:name="Acquire Seats Info"/>
             <!-- 再把响应消息扔到了acquireFlightPriceQueue队列，等待响应 -->
             <vm:outbound-endpoint exchange-pattern="request-response" path="acquireFlightPriceQueue" doc:name="Acquire Flight Price" />

             <!-- 更新totalPrice变量的值，把本次迭代的票价加到总价中 -->
             <set-variable variableName="totalPrice" value="#[totalPrice + payload.ticketPrice]" doc:name="Add price to totalPrice" />
         </foreach>

         <expression-component doc:name="Add total price to reservation">
             <![CDATA[payload.totalPrice = flowVars['totalPrice']]]>
         </expression-component>
         <!-- 把响应对象转换为JSON, 航班预定处理结束 -->
         <json:object-to-json-transformer doc:name="Object to JSON" />

         <!-- 异常捕获区 -->
         <choice-exception-strategy doc:name="Choice Exception Strategy">
             <!--  -->
             <catch-exception-strategy when="#[exception.causedBy(org.mule.example.FlightUnavailableException)]" doc:name="Catch Exception Strategy">
                 <scripting:transformer doc:name="Add no avaiilability error">
                     <scripting:script engine="Groovy">
                         <![CDATA[
 def payload = new org.mule.example.ReservationResponse()
 payload.addError('There is no availability for the selected flight!')
 payload]]>
                     </scripting:script>
                 </scripting:transformer>
                 <json:object-to-json-transformer doc:name="Object to JSON" />
             </catch-exception-strategy>

             <catch-exception-strategy doc:name="Catch Exception Strategy">
                 <scripting:transformer doc:name="Add exception message">
                     <scripting:script engine="Groovy">
                         <![CDATA[
 def payload = new org.mule.example.ReservationResponse()
 payload.addError('Error processing request!')
 payload]]>
                     </scripting:script>
                 </scripting:transformer>
                 <set-property propertyName="http.status" value="500" doc:name="Set http status 500" />
                 <json:object-to-json-transformer doc:name="Object to JSON" />
             </catch-exception-strategy>
         </choice-exception-strategy>
     </flow>

     <!--
     应用启动时，该流服务随之启动，然后在vm://acquireFlightPriceQueue上等待请求
      -->
     <flow name="acquireSeatsInfo">
         <!-- 在acquireSeatsInfoQueue路径上等待输入座位信息 -->
         <vm:inbound-endpoint exchange-pattern="request-response" path="acquireSeatsInfoQueue" doc:name="VM"/>

         <!-- 使用脚本进行处理 -->
         <scripting:component doc:name="Acquire seats info service">
             <scripting:script engine="Groovy"><![CDATA[
 if (payload.flightNumber.endsWith('2'))
     payload.seatInfo = '20A'
 else
     throw new Exception('No seat info available')
 payload]]></scripting:script>
         </scripting:component>

         <!-- 异常处理 -->
         <catch-exception-strategy doc:name="Catch Exception Strategy">
             <expression-component doc:name="Add no seat info available message"><![CDATA[payload.seatInfo = 'No seat info available']]></expression-component>
         </catch-exception-strategy>
     </flow>

     <!-- 

     如：下面的path="acquireFlightPriceQueue"配置拼写不对
 ********************************************************************************
 Message               : There is no receiver registered on connector "connector.VM.mule.default" for endpointUri vm://acquireFlightPriceQueue
 Code                  : MULE_ERROR-0
 在端点地址为vm://acquireFlightPriceQueue的连接器上没有注册接收者
 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 Exception stack is:
 1. There is no receiver registered on connector "connector.VM.mule.default" for endpointUri vm://acquireFlightPriceQueue (org.mule.api.transport.NoReceiverForEndpointException)
   org.mule.transport.vm.VMMessageDispatcher:85 (http://www.mulesoft.org/docs/site/current3/apidocs/org/mule/api/transport/NoReceiverForEndpointException.html)
 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 Root Exception stack trace:
 org.mule.api.transport.NoReceiverForEndpointException: There is no receiver registered on connector "connector.VM.mule.default" for endpointUri vm://acquireFlightPriceQueue
     at org.mule.transport.vm.VMMessageDispatcher.doSend(VMMessageDispatcher.java:85)
     at org.mule.transport.AbstractMessageDispatcher.process(AbstractMessageDispatcher.java:81)
     at org.mule.transport.AbstractConnector$DispatcherMessageProcessor.process(AbstractConnector.java:2627)
     + 3 more (set debug level logging or '-Dmule.verbose.exceptions=true' for everything)
 ********************************************************************************
     航班的票价计算怪怪的，编号*2： payload.ticketPrice = Integer.valueOf(payload.flightNumber) * 2
      -->
     <flow name="acquireFlightPrice">
         <vm:inbound-endpoint exchange-pattern="request-response" path="acquireFlightPriceQueue" doc:name="acquireFlightPrice"/>
         <expression-component doc:name="acquireFlightPrice">
             <![CDATA[payload.ticketPrice = Integer.valueOf(payload.flightNumber) * 2]]>
         </expression-component>
     </flow>
 </mule>

3 相关类定义

1）Flight -- 航班信息类

 package org.mule.example;

 import java.io.Serializable;

 public class Flight implements Serializable {

     /**
      *
      */
     private static final long serialVersionUID = -841916700389246787L;

     private String flightNumber;
     private String seatInfo;
     private Double ticketPrice;

     public String getFlightNumber() {
         return flightNumber;
     }

     public void setFlightNumber(String flightNumber) {
         this.flightNumber = flightNumber;
     }

     public String getSeatInfo() {
         return seatInfo;
     }

     public void setSeatInfo(String seatInfo) {
         this.seatInfo = seatInfo;
     }

     public Double getTicketPrice() {
         return ticketPrice;
     }

     public void setTicketPrice(Double ticketPrice) {
         this.ticketPrice = ticketPrice;
     }
 }

2）ReservationRequest -- 请求消息负载内容类

 package org.mule.example;

 import java.io.Serializable;

 public class ReservationRequest implements Serializable {

     /**
      *
      */
     private static final long serialVersionUID = 3502244785792589115L;

     private Flight[] flights;

     public Flight[] getFlights() {
         return flights;
     }

     public void setFlights(Flight[] flights) {
         this.flights = flights;
     }
 }

3）ReservationResponse 响应消息负载内容类

 package org.mule.example;

 import java.io.Serializable;
 import java.util.ArrayList;
 import java.util.List;

 public class ReservationResponse implements Serializable {

     private List<String> errors = new ArrayList<String>();

     private Flight[] flights;
     public Double totalPrice;

     public Double getTotalPrice() {
         return totalPrice;
     }
     public void setTotalPrice(Double totalPrice) {
         this.totalPrice = totalPrice;
     }

     public List<String> getErrors() {
         return errors;
     }
     public void setErrors(List<String> errors) {
         this.errors = errors;
     }

     public Flight[] getFlights() {
         return flights;
     }
     public void setFlights(Flight[] flights) {
         this.flights = flights;
     }

     //------ 添加错误信息---------------------
     public void addError(String error) {
         errors.add(error);
     }

     //------- 原始请求对象---------------------
     private ReservationRequest originalRequest;

     public ReservationRequest getOriginalRequest() {
         return originalRequest;
     }

     public void setOriginalRequest(ReservationRequest originalRequest) {
         this.originalRequest = originalRequest;
     }
 }

4）FlightUnavailableException 异常类

 package org.mule.example;

 public class FlightUnavailableException extends Exception {

 }

4 Ajax访问页面

1）index.html

 <!DOCTYPE html>
 <html>
 <head>
     <link href="flight-reservation.css" rel="stylesheet" type="text/css"/>
     <script type="text/javascript" src="mule-resource/js/mule.js"></script>
     <script type="text/javascript" src="flight-reservation.js"></script>
 </head>
 <body onload="onload();">
 <div class="content">
     <div class="flightReservationHeader"> Flight Reservation System </div>
     <div id="title"> Search Best Flight </div>
     <div class="searchBox">
         <form id="searchFlight">
             <div class="cities">
                 <div id="origin">
                     <div>Origin</div>
                     <select class="origin" id="originCity">
                         <option value=""></option>
                         <option value="BUE">Buenos Aires (BUE)</option>
                     </select>
                 </div>
                 <div id="destination">
                     <div>Destination</div>
                     <select class="destination" id="destinationCity">
                         <option value=""></option>
                         <option value="MOW">Moscu (MOW) </option>
                         <option value="HKG">Hong Kong (HKG) </option>
                         <option value="TW">Tai Wang (TW)</option>
                     </select>
                 </div>
             </div>
         </form>
         <div id="makeSearch">
             <input id="searchButton" type="button" value="Search" onClick="makeSearch(dojo.byId('originCity').value, dojo.byId('destinationCity').value)">
         </div>
     </div>
     <div class="response">
         <div id="error"><div id="errorMessage"></div></div>
         <div id="searchResults"></div>
     </div>
 </div>
 </body>
 </html>

2) flight-reservation.js

 function onload() {
     dojo.byId("error").style.display = "none";
     dojo.byId("searchResults").style.display = "none";
 }

 //发送航班请求
 function makeSearch(origin, destination) {
     var request="";

     if (origin == "BUE" && destination == "MOW")
     {

         var request = {
                 "flights": [
                         {"flightNumber":912},
                         {"flightNumber":1022},
                         {"flightNumber":732}
                            ]
                     };
         mule.rpc("/searchFlights", JSON.stringify(request), processResponse);
     }
     else if (origin == "BUE" && destination == "HKG")
     {
         var request = {
                 "flights":[
                         {"flightNumber":822},
                         {"flightNumber":1133}
                           ]
                     };
         mule.rpc("/searchFlights", JSON.stringify(request), processResponse);
     }
     else if (origin == "BUE" && destination == "TW")
     {
         var request = {
                 "flights":[
                         {"flightNumber":822},
                         {"flightNumber":1004}
                           ]
                     };
         mule.rpc("/searchFlights", JSON.stringify(request), processResponse);
     }
     else
     {
         var request={"Invalid Request":[]};
         mule.rpc("/searchFlights", JSON.stringify(request), processResponse);
     }
 }

 //处理响应
 function processResponse(message) {
     resp = JSON.parse("[" + message.data + "]")[0];

     if(resp.errors == "")
     {
         dojo.byId("error").style.display = "none";
         dojo.byId("searchResults").style.display = "block";

         var results = "<table class='results'>";
         results += "<th>Flight Number</th><th>Seat assignment</th><th>Price</th>"

         for(var i = 0; i < resp.flights.length;i++)
         {
             results +="<tr><td>" + resp.flights[i].flightNumber + "</td><td>" + resp.flights[i].seatInfo + "</td><td>$" + resp.flights[i].ticketPrice + "</td></tr>";
         }

         results += "<tr><td colspan='3'><div id='totalPrice'>Total price is $" + resp.totalPrice + "</div></td><tr>"
         results += "</table>";

         dojo.byId("searchResults").innerHTML = results;
     }
     else
     {
         dojo.byId("error").style.display = "block";
         dojo.byId("searchResults").style.display = "none";
         dojo.byId("errorMessage").innerHTML = resp.errors;
     }
 }

3) flight-reservation.css

 .content {
     padding: 20px 0 20px 50px;
     width: 620px;
     color: #003399;
     background-color: #F8F8FF
 }

 .flightReservationHeader {
     text-align: center;
     font-weight: bold;
     padding-bottom: 20px;
     font-size: 1.8em;
 }

 #title {
     padding-top: 5px;
     font-weight: bold;
     background-color: #E8EDFF;
     width: 150px;
     height: 25px;
     border: 2px solid #B9C9FE;
     text-align: center
 }

 .searchBox {
     width: 550px;
     background-color: #E8EDFF;
     border: 2px solid #B9C9FE;
     position: relative;
     padding-bottom: 30px;
     padding-top: 20px
 }

 .cities {
     padding: 10px 35px 10px 35px
 }

 #origin {
     float: left;
     padding-right: 50px
 }

 .origin {
     width: 215px
 }

 .destination {
     width: 215px
 }

 #destination {
     float: left
 }

 #makeSearch {
     clear: both;
     padding: 20px 0 10px 40px;
     position: relative;
 }

 #searchButton {
     background-color: #B9C9FE
 }

 #error {
     width: 550px;
     height: 50px;
     color: #FF0000;
     text-align: center;
     background-color: #FFDAB9;
     border: 2px solid #FF0000;
     display: none
 }

 #errorMessage {
     padding: 10px
 }

 .response {
     padding-top: 30px
 }

 .response table {
     width: 550px;
 }

 .response table th {
     background: none repeat scroll 0 0 #B9C9FE;
     border-bottom: 1px solid #FFFFFF;
     border-top: 4px solid #AABCFE;
     color: #003399;
     padding: 8px
 }

 .response table td {
     background: none repeat scroll 0 0 #E8EDFF;
     border-bottom: 1px solid #FFFFFF;
     border-top: 1px solid transparent;
     color: #666699;
     padding: 8px;
 }

 #totalPrice {
     float: right;
     font-weight: bold
 }

5 执行效果分析

1）flights编号都以'2'结尾，所以正常运行

2）该请求包含了一个以'3'结尾的航班编号，触发该航班不可得异常

3）尾号为2的航班，分配的座位都是'20A'；尾号为3的航班，不可得；尾号不是2、3的航班没座位