/// <summary>
/// Parses a download feed message
/// </summary>
/// <param name="version">The version of the protocol being used</param>
/// <param name="operationType">The operation that is being performed</param>
/// <param name="messageBody">The ValueSet that contains all of the fields</param>
private static ISocialInfoMessage ParseDownloadFeedMessage(
UInt32 version,
OperationType operationType,
ValueSet messageBody)
{
UInt32 operationId = (UInt32)ParseField(messageBody, MessageBodyPayloadField.OperationId);
string ownerRemoteId = ParseField(messageBody, MessageBodyPayloadField.OwnerRemoteId) as string;
// This is an optional field
string lastFeedItemRemoteId = ParseField(
messageBody,
MessageBodyPayloadField.LastFeedItemRemoteId,
false) as string;
DateTimeOffset?lastFeedItemTimestamp =
ParseField(messageBody, MessageBodyPayloadField.LastFeedItemTimestamp) as DateTimeOffset?;
UInt32 itemCount = (UInt32)ParseField(messageBody, MessageBodyPayloadField.ItemCount);
bool isFetchMore = (bool)ParseField(messageBody, MessageBodyPayloadField.IsFetchMore);
Type objectType = null;
switch (operationType)
{
case OperationType.DownloadContactFeed:
objectType = typeof(DownloadContactFeedMessage);
break;
case OperationType.DownloadDashboardFeed:
objectType = typeof(DownloadDashboardFeedMessage);
break;
case OperationType.DownloadHomeFeed:
objectType = typeof(DownloadHomeFeedMessage);
break;
default:
throw new ArgumentException("Unexpected feed type");
}
// Create the message using the type information from above
ISocialInfoMessage message = Activator.CreateInstance(
objectType,
new object[]
{
version,
operationId,
ownerRemoteId,
lastFeedItemRemoteId,
lastFeedItemTimestamp.Value.DateTime,
itemCount,
isFetchMore
}) as ISocialInfoMessage;
return(message);
}
/// <summary>
/// Parses a message and creates the appropriate ISocialMessage type.
/// </summary>
/// <param name="messageBody">
/// The ValueSet that contains all of the key-value pairs
/// </param>
/// <returns>An ISocialInfoMessage for the operation</returns>
public static ISocialInfoMessage CreateSocialInfoMessage(ValueSet messageBody)
{
// Get the operation type to determine which type of message to create.
UInt32 type = (UInt32)ParseField(messageBody, MessageBodyPayloadField.Type);
// Get the version of the message
UInt32 version = (UInt32)ParseField(messageBody, MessageBodyPayloadField.Version);
// At this point, we have enough information to construct the specific message type.
OperationType operationType = (OperationType)(type);
ISocialInfoMessage message = null;
switch (operationType)
{
case OperationType.GoodBye:
message = new GoodByeMessage(version);
break;
case OperationType.DownloadContactFeed:
case OperationType.DownloadDashboardFeed:
case OperationType.DownloadHomeFeed:
message = ParseDownloadFeedMessage(version, operationType, messageBody);
break;
case OperationType.GetNext:
message = new GetNextOperationMessage(version);
break;
case OperationType.OperationResult:
message = ParseOperationResultMessage(version, messageBody);
break;
default:
throw new ArgumentException("The operation type is not valid.");
}
return(message);
}
public async void Run(IBackgroundTaskInstance taskInstance)
{
// Get the task deferral and the app service connection
this.mTaskDeferral = taskInstance.GetDeferral();
AppServiceTriggerDetails triggerDetails =
taskInstance.TriggerDetails as AppServiceTriggerDetails;
this.mAppServiceConnection = triggerDetails.AppServiceConnection;
// Continue processing messages until the GoodBye message is sent
bool continueProcessing = true;
// Before exiting, this method needs to complete the deferral that
// was acquired. Catch all exceptions that may be thrown.
try
{
while (continueProcessing)
{
// Create a next operation message to send to the app
GetNextOperationMessage getNextOperationMessage =
new GetNextOperationMessage(SocialAppContactVersion);
// Send a message to the app
AppServiceResponse response =
await this.mAppServiceConnection.SendMessageAsync(
getNextOperationMessage.Serialize());
if (response == null)
{
throw new InvalidOperationException("A null response was received.");
}
// Check the status
if (response.Status != AppServiceResponseStatus.Success)
{
throw new Exception(String.Format(
"App service response was unsuccessful. Status = {0}",
response.Status));
}
// Parse the response to get the correct message type
ISocialInfoMessage message =
SocialInfoMessageFactory.CreateSocialInfoMessage(response.Message);
// Check the version of the message
// If the version of the message is not the expected version by this agent,
// then there was a protocol change in the People app. You will need to
// contact the People app team at Microsoft to get the most up-to-date
// protocol definition.
if (message.MajorVersion != cSocialAppContactMajorVersion)
{
throw new InvalidOperationException(
"This version of the protocol is not supported.");
}
// Handle the message based on its type
switch (message.OperationType)
{
case OperationType.DownloadContactFeed:
case OperationType.DownloadDashboardFeed:
case OperationType.DownloadHomeFeed:
// Cast the message to an ISocialInfoDownloadFeedMessage
ISocialInfoDownloadFeedMessage downloadFeedMessage =
message as ISocialInfoDownloadFeedMessage;
// Keep track of the operation ID to report it
UInt32 operationId = downloadFeedMessage.OperationId;
// Save the error code associated with the operation
UInt32 errorCode = 0;
try
{
// Download the feed
await downloadFeedMessage.DownloadFeedAsync();
}
catch (Exception exception)
{
errorCode = (UInt32)exception.HResult;
}
// Create the operation result message
OperationResultMessage resultMessage =
new OperationResultMessage(
SocialAppContactVersion,
errorCode,
downloadFeedMessage.OperationId);
// Send the result back to the app
await this.mAppServiceConnection.SendMessageAsync(
resultMessage.Serialize());
break;
case OperationType.GoodBye:
continueProcessing = false;
break;
default:
throw new InvalidOperationException(
"The selected operation type is not supported.");
}
}
}
catch
{
// Throw the exception
throw;
}
finally
{
// Complete the task deferral
this.mTaskDeferral.Complete();
this.mTaskDeferral = null;
this.mAppServiceConnection = null;
}
}
