beagled/QueryExecutor.cs

   1 //
   2 // QueryExecutor.cs
   3 //
   4 // Copyright (C) 2005 Novell, Inc.
   5 //
   6
   7 //
   8 // Permission is hereby granted, free of charge, to any person obtaining a
   9 // copy of this software and associated documentation files (the "Software"),
  10 // to deal in the Software without restriction, including without limitation
  11 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12 // and/or sell copies of the Software, and to permit persons to whom the
  13 // Software is furnished to do so, subject to the following conditions:
  14 //
  15 // The above copyright notice and this permission notice shall be included in
  16 // all copies or substantial portions of the Software.
  17 //
  18 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  21 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  23 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  24 // DEALINGS IN THE SOFTWARE.
  25 //
  26
  27 using System;
  28 using System.Collections;
  29 using System.Xml.Serialization;
  30
  31 using Beagle.Util;
  32
  33 namespace Beagle.Daemon {
  34
  35         [RequestMessage (typeof (Query))]
  36         public class QueryExecutor : RequestMessageExecutor {
  37
  38                 private Query query;
  39                 private QueryResult result;
  40
  41                 private void DisconnectResult ()
  42                 {
  43                         this.result.HitsAddedEvent -= OnResultHitsAdded;
  44                         this.result.HitsSubtractedEvent -= OnResultHitsSubtracted;
  45                         this.result.FinishedEvent -= OnResultFinished;
  46                         this.result.CancelledEvent -= OnResultCancelled;
  47
  48                         this.result.Cancel ();
  49                         this.result.Dispose ();
  50                 }
  51
  52                 private void AttachResult ()
  53                 {
  54                         this.result.HitsAddedEvent += OnResultHitsAdded;
  55                         this.result.HitsSubtractedEvent += OnResultHitsSubtracted;
  56                         this.result.FinishedEvent += OnResultFinished;
  57                         this.result.CancelledEvent += OnResultCancelled;
  58                 }
  59
  60                 public void OnResultHitsAdded (QueryResult result, ICollection some_hits)
  61                 {
  62                         HitsAddedResponse response = new HitsAddedResponse (some_hits);
  63
  64                         this.SendAsyncResponse (response);
  65                 }
  66
  67                 public void OnResultHitsSubtracted (QueryResult result, ICollection some_uris)
  68                 {
  69                         HitsSubtractedResponse response = new HitsSubtractedResponse (some_uris);
  70
  71                         this.SendAsyncResponse (response);
  72                 }
  73
  74                 public void OnResultFinished (QueryResult result)
  75                 {
  76                         this.SendAsyncResponse (new FinishedResponse ());
  77                 }
  78
  79                 public void OnResultCancelled (QueryResult result)
  80                 {
  81                         this.SendAsyncResponse (new CancelledResponse ());
  82                 }
  83
  84                 private void OnQueryDriverChanged (Queryable queryable, IQueryableChangeData change_data)
  85                 {
  86                         if (this.result != null)
  87                                 QueryDriver.DoOneQuery (queryable, this.query, this.result, change_data);
  88                 }
  89
  90                 public override ResponseMessage Execute (RequestMessage req)
  91                 {
  92                         this.query = (Query) req;
  93
  94                         this.result = new QueryResult ();
  95                         AttachResult ();
  96
  97                         QueryDriver.ChangedEvent += OnQueryDriverChanged;
  98                         QueryDriver.DoQuery (query,
  99                                              this.result,
 100                                              new RequestMessageExecutor.AsyncResponse (this.SendAsyncResponse));
 101
 102                         // Don't send a response; we'll be sending them async
 103                         return null;
 104                 }
 105
 106                 public override void Cleanup ()
 107                 {
 108                         DisconnectResult ();
 109                 }
 110         }
 111 }