/// <summary>
/// Enqueue a Web Service record into the record queue
/// </summary>
public static void EnqueueRequestRecord(string queueName, RequestRecord newRecord)
{
bool enableQueueOptimization = false; // turn off the queue optimization (doesn't work with introduction of tags)
List <RequestRecord> requests = new List <RequestRecord>();
DataContractJsonSerializer dc = new DataContractJsonSerializer(requests.GetType());
if (newRecord.SerializedBody == null)
{
newRecord.SerializeBody();
}
using (IsolatedStorageFile file = IsolatedStorageFile.GetUserStoreForApplication())
{
lock (fileLocks[queueName])
{
// if the file opens, read the contents
using (IsolatedStorageFileStream stream = new IsolatedStorageFileStream(QueueFilename(queueName), FileMode.OpenOrCreate, file))
{
try
{
// if the file opened, read the record queue
requests = dc.ReadObject(stream) as List <RequestRecord>;
if (requests == null)
{
requests = new List <RequestRecord>();
}
}
catch (Exception ex)
{
stream.Position = 0;
string s = new StreamReader(stream).ReadToEnd();
TraceHelper.AddMessage(String.Format("Exception in deserializing RequestRQueue: {0}; record: {1}", ex.Message, s));
}
if (enableQueueOptimization == true)
{
OptimizeQueue(newRecord, requests);
}
else
{
// this is a new record so add the new record at the end
requests.Add(newRecord);
}
// reset the stream and write the new record queue back to the file
stream.SetLength(0);
stream.Position = 0;
dc.WriteObject(stream, requests);
stream.Flush();
}
}
}
}
/// <summary>
/// Helper method to update an existing queue record with new information
/// </summary>
/// <param name="requests"></param>
/// <param name="existingRecord"></param>
/// <param name="newRecord"></param>
/// <returns>Whether an update was performed</returns>
private static bool UpdateExistingRecord(List <RequestRecord> requests, RequestRecord existingRecord, RequestRecord newRecord)
{
switch (existingRecord.ReqType)
{
case RequestRecord.RequestType.Delete:
// the existing record in the queue is a delete - this situation can't happen unless there is local corruption (but not necessarily queue corruption)
// there can be no further action
if (System.Diagnostics.Debugger.IsAttached)
{
throw new Exception("trying to do something to an already deleted entry");
}
return(false);
case RequestRecord.RequestType.Insert:
// the existing record in the queue is an insert
switch (newRecord.ReqType)
{
case RequestRecord.RequestType.Delete:
// the entity was created and deleted while offline
// the existing record needs to be removed
requests.Remove(existingRecord);
return(true);
case RequestRecord.RequestType.Insert:
// this doesn't make sense because it violates the Guid uniqueness principle
// since the record already exists, we're not going to insert a new one - take no action
if (System.Diagnostics.Debugger.IsAttached)
{
throw new Exception("insert after an insert");
}
return(false);
case RequestRecord.RequestType.Update:
// an update on top of an insert
// replace the new value in the existing insert record with the "new" value in the update
switch (existingRecord.BodyTypeName)
{
case "Tag":
List <Tag> newRecordTagList = (List <Tag>)newRecord.Body;
existingRecord.Body = newRecordTagList[1];
break;
case "Item":
List <Item> newRecordFolder = (List <Item>)newRecord.Body;
existingRecord.Body = newRecordFolder[1];
break;
case "Folder":
List <Folder> newRecordFolderList = (List <Folder>)newRecord.Body;
existingRecord.Body = newRecordFolderList[1];
break;
}
// reserialize the body
existingRecord.SerializeBody();
return(true);
}
break;
case RequestRecord.RequestType.Update:
// the existing record in the queue is an update
switch (newRecord.ReqType)
{
case RequestRecord.RequestType.Delete:
// the entity was updated and now deleted while offline
// the existing record needs to be amended to a delete record
existingRecord.Copy(newRecord);
return(true);
case RequestRecord.RequestType.Insert:
// this doesn't make sense because it violates the Guid uniqueness principle
// since the record already exists, we're not going to insert a new one - take no action
if (System.Diagnostics.Debugger.IsAttached)
{
throw new Exception("insert after an update");
}
return(false);
case RequestRecord.RequestType.Update:
// an update on top of an update
// replace the new value in the existing record with the "new" new value
switch (existingRecord.BodyTypeName)
{
case "Tag":
List <Tag> existingRecordTagList = (List <Tag>)existingRecord.Body;
List <Tag> newRecordTagList = (List <Tag>)newRecord.Body;
existingRecordTagList[1] = newRecordTagList[1];
break;
case "Item":
List <Item> existingRecordFolder = (List <Item>)existingRecord.Body;
List <Item> newRecordFolder = (List <Item>)newRecord.Body;
existingRecordFolder[1] = newRecordFolder[1];
break;
case "Folder":
List <Folder> existingRecordFolderList = (List <Folder>)existingRecord.Body;
List <Folder> newRecordFolderList = (List <Folder>)newRecord.Body;
existingRecordFolderList[1] = newRecordFolderList[1];
break;
}
// reserialize the body
existingRecord.SerializeBody();
return(true);
}
break;
}
// no case was triggered - this is an exceptional situation
if (System.Diagnostics.Debugger.IsAttached)
{
throw new Exception("queue corrupted");
}
return(false);
}
/// <summary>
/// Enqueue a Web Service record into the record queue
/// </summary>
public static void EnqueueRequestRecord(RequestRecord newRecord)
{
bool enableQueueOptimization = false; // turn off the queue optimization (doesn't work with introduction of tags)
List<RequestRecord> requests = new List<RequestRecord>();
DataContractJsonSerializer dc = new DataContractJsonSerializer(requests.GetType());
if (newRecord.SerializedBody == null)
newRecord.SerializeBody();
using (IsolatedStorageFile file = IsolatedStorageFile.GetUserStoreForApplication())
{
lock (fileLock)
{
// if the file opens, read the contents
using (IsolatedStorageFileStream stream = new IsolatedStorageFileStream(@"RequestRecords.xml", FileMode.OpenOrCreate, file))
{
try
{
// if the file opened, read the record queue
requests = dc.ReadObject(stream) as List<RequestRecord>;
if (requests == null)
requests = new List<RequestRecord>();
}
catch (Exception)
{
stream.Position = 0;
string s = new StreamReader(stream).ReadToEnd();
}
if (enableQueueOptimization == true)
{
OptimizeQueue(newRecord, requests);
}
else
{
// this is a new record so add the new record at the end
requests.Add(newRecord);
}
// reset the stream and write the new record queue back to the file
stream.SetLength(0);
stream.Position = 0;
dc.WriteObject(stream, requests);
stream.Flush();
}
}
}
}
/// <summary>
/// Helper method to update an existing queue record with new information
/// </summary>
/// <param name="requests"></param>
/// <param name="existingRecord"></param>
/// <param name="newRecord"></param>
/// <returns>Whether an update was performed</returns>
private static bool UpdateExistingRecord(List<RequestRecord> requests, RequestRecord existingRecord, RequestRecord newRecord)
{
switch (existingRecord.ReqType)
{
case RequestRecord.RequestType.Delete:
// the existing record in the queue is a delete - this situation can't happen unless there is local corruption (but not necessarily queue corruption)
// there can be no further action
if (System.Diagnostics.Debugger.IsAttached)
throw new Exception("trying to do something to an already deleted entry");
return false;
case RequestRecord.RequestType.Insert:
// the existing record in the queue is an insert
switch (newRecord.ReqType)
{
case RequestRecord.RequestType.Delete:
// the entity was created and deleted while offline
// the existing record needs to be removed
requests.Remove(existingRecord);
return true;
case RequestRecord.RequestType.Insert:
// this doesn't make sense because it violates the Guid uniqueness principle
// since the record already exists, we're not going to insert a new one - take no action
if (System.Diagnostics.Debugger.IsAttached)
throw new Exception("insert after an insert");
return false;
case RequestRecord.RequestType.Update:
// an update on top of an insert
// replace the new value in the existing insert record with the "new" value in the update
switch (existingRecord.BodyTypeName)
{
case "Tag":
List<Tag> newRecordTagList = (List<Tag>)newRecord.Body;
existingRecord.Body = newRecordTagList[1];
break;
case "Task":
List<Task> newRecordTaskList = (List<Task>)newRecord.Body;
existingRecord.Body = newRecordTaskList[1];
break;
case "TaskList":
List<TaskList> newRecordTaskListList = (List<TaskList>)newRecord.Body;
existingRecord.Body = newRecordTaskListList[1];
break;
}
// reserialize the body
existingRecord.SerializeBody();
return true;
}
break;
case RequestRecord.RequestType.Update:
// the existing record in the queue is an update
switch (newRecord.ReqType)
{
case RequestRecord.RequestType.Delete:
// the entity was updated and now deleted while offline
// the existing record needs to be amended to a delete record
existingRecord.Copy(newRecord);
return true;
case RequestRecord.RequestType.Insert:
// this doesn't make sense because it violates the Guid uniqueness principle
// since the record already exists, we're not going to insert a new one - take no action
if (System.Diagnostics.Debugger.IsAttached)
throw new Exception("insert after an update");
return false;
case RequestRecord.RequestType.Update:
// an update on top of an update
// replace the new value in the existing record with the "new" new value
switch (existingRecord.BodyTypeName)
{
case "Tag":
List<Tag> existingRecordTagList = (List<Tag>)existingRecord.Body;
List<Tag> newRecordTagList = (List<Tag>)newRecord.Body;
existingRecordTagList[1] = newRecordTagList[1];
break;
case "Task":
List<Task> existingRecordTaskList = (List<Task>)existingRecord.Body;
List<Task> newRecordTaskList = (List<Task>)newRecord.Body;
existingRecordTaskList[1] = newRecordTaskList[1];
break;
case "TaskList":
List<TaskList> existingRecordTaskListList = (List<TaskList>)existingRecord.Body;
List<TaskList> newRecordTaskListList = (List<TaskList>)newRecord.Body;
existingRecordTaskListList[1] = newRecordTaskListList[1];
break;
}
// reserialize the body
existingRecord.SerializeBody();
return true;
}
break;
}
// no case was triggered - this is an exceptional situation
if (System.Diagnostics.Debugger.IsAttached)
throw new Exception("queue corrupted");
return false;
}