mcs/class/Mono.Messaging.RabbitMQ/Mono.Messaging.RabbitMQ/RabbitMQMessageEnumerator.cs

   1 //
   2 // Mono.Messaging.RabbitMQ
   3 //
   4 // Authors:
   5 //        Michael Barker (mike@middlesoft.co.uk)
   6 //
   7 // (C) 2008 Michael Barker
   8 //
   9
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31 using System;
  32
  33 using Mono.Messaging;
  34
  35 using RabbitMQ.Client;
  36 using RabbitMQ.Client.Content;
  37 using RabbitMQ.Client.Events;
  38 using RabbitMQ.Client.Exceptions;
  39 using RabbitMQ.Client.MessagePatterns;
  40 using RabbitMQ.Util;
  41
  42 namespace Mono.Messaging.RabbitMQ {
  43
  44         public class RabbitMQMessageEnumerator : IMessageEnumerator {
  45
  46                 private readonly MessageFactory helper;
  47                 private readonly QueueReference qRef;
  48                 private IConnection cn = null;
  49                 private BasicDeliverEventArgs current = null;
  50                 private IModel model = null;
  51                 private Subscription subscription = null;
  52
  53                 public RabbitMQMessageEnumerator (MessageFactory helper,
  54                                                   QueueReference qRef) {
  55                         this.helper = helper;
  56                         this.qRef = qRef;
  57                 }
  58
  59                 public IMessage Current {
  60                         get {
  61                                 if (current == null)
  62                                         throw new InvalidOperationException ();
  63
  64                                 return CreateMessage (current);
  65                         }
  66                 }
  67
  68                 public IntPtr CursorHandle {
  69                         get { throw new NotImplementedException (); }
  70                 }
  71
  72                 public void Close ()
  73                 {
  74                         if (subscription != null) {
  75                                 subscription.Close ();
  76                                 subscription = null;
  77                         }
  78
  79                         if (model != null) {
  80                                 model.Dispose ();
  81                                 model = null;
  82                         }
  83
  84                         if (cn != null) {
  85                                 cn.Dispose ();
  86                                 cn = null;
  87                         }
  88                 }
  89
  90                 public void Dispose (bool disposing)
  91                 {
  92                 }
  93
  94                 public void Dispose ()
  95                 {
  96                         Close ();
  97                 }
  98
  99                 public void Reset ()
 100                 {
 101                         Close ();
 102                 }
 103
 104                 private IModel Model {
 105                         get {
 106                                 if (cn == null) {
 107                                         ConnectionFactory cf = new ConnectionFactory ();
 108                                         cf.Address = qRef.Host;
 109                                         cn = cf.CreateConnection ();
 110                                 }
 111
 112                                 if (model == null) {
 113                                         model = cn.CreateModel ();
 114                                 }
 115
 116                                 return model;
 117                         }
 118                 }
 119
 120                 private Subscription Subscription {
 121                         get {
 122                                 if (subscription == null) {
 123                                         IModel ch = Model;
 124
 125                                         string finalName = ch.QueueDeclare (qRef.Queue, false);
 126
 127                                         subscription = new Subscription (ch, finalName);
 128                                 }
 129
 130                                 return subscription;
 131                         }
 132                 }
 133
 134                 public bool MoveNext ()
 135                 {
 136                         Subscription sub = Subscription;
 137                         return sub.Next (500, out current);
 138                 }
 139
 140                 public bool MoveNext (TimeSpan timeout)
 141                 {
 142                         int to = MessageFactory.TimeSpanToInt32 (timeout);
 143                         return Subscription.Next (to, out current);
 144                 }
 145
 146                 public IMessage RemoveCurrent ()
 147                 {
 148                         if (current == null)
 149                                 throw new InvalidOperationException ();
 150
 151                         IMessage msg = CreateMessage (current);
 152                         Subscription.Ack (current);
 153                         return msg;
 154                 }
 155
 156                 public IMessage RemoveCurrent (IMessageQueueTransaction transaction)
 157                 {
 158                         throw new NotSupportedException ("Unable to remove messages within a transaction");
 159                 }
 160
 161                 public IMessage RemoveCurrent (MessageQueueTransactionType transactionType)
 162                 {
 163                         throw new NotSupportedException ("Unable to remove messages within a transaction");
 164                 }
 165
 166                 public IMessage RemoveCurrent (TimeSpan timeout)
 167                 {
 168                         // Timeout makes no sense for this implementation, so we just work
 169                         // the same as the non-timeout based one.
 170
 171                         if (current == null)
 172                                 throw new InvalidOperationException ();
 173
 174                         IMessage msg = CreateMessage (current);
 175                         Subscription.Ack (current);
 176                         return msg;
 177                 }
 178
 179                 public IMessage RemoveCurrent (TimeSpan timeout, IMessageQueueTransaction transaction)
 180                 {
 181                         throw new NotImplementedException ();
 182                 }
 183
 184                 public IMessage RemoveCurrent (TimeSpan timeout, MessageQueueTransactionType transactionType)
 185                 {
 186                         throw new NotImplementedException ();
 187                 }
 188
 189                 private IMessage CreateMessage (BasicDeliverEventArgs result)
 190                 {
 191                         return helper.ReadMessage (qRef, result);
 192                 }
 193
 194         }
 195 }