/// <summary>
/// Create a Queue that will be used by the Consumer.
/// </summary>
/// <param name="queue">Queue to create.</param>
/// <returns>Instance of the created Queue.</returns>
private queueType CreateQueue(queueType queue)
{
string url = $"{EnvironmentUtils.ParseServiceUrl(Environment, ServiceType.UTILITY, InfrastructureServiceNames.queues)}";
string body = SerialiseQueue(queue);
string xml = HttpUtils.PostRequest(url, RegistrationService.AuthorisationToken, body);
if (log.IsDebugEnabled) log.Debug($"Response from POST {url} request ...");
if (log.IsDebugEnabled) log.Debug(xml);
return DeserialiseQueue(xml);
}
/// <summary>
/// Create a Queue that will be used by the Consumer.
/// </summary>
/// <param name="queue">Queue to create.</param>
/// <returns>Instance of the created Queue.</returns>
private queueType CreateQueue(queueType queue)
{
string url = $"{EnvironmentUtils.ParseServiceUrl(Environment, ServiceType.UTILITY, InfrastructureServiceNames.queues)}";
string requestBody = SerialiseQueue(queue);
string responseBody = HttpUtils.PostRequest(
url,
RegistrationService.AuthorisationToken,
requestBody,
contentTypeOverride: ContentType.ToDescription(),
acceptOverride: Accept.ToDescription());
if (log.IsDebugEnabled)
{
log.Debug($"Response from POST {url} request ...");
}
if (log.IsDebugEnabled)
{
log.Debug(responseBody);
}
return(DeserialiseQueue(responseBody));
}
/// <summary>
/// <see cref="IEventConsumer.Start(string, string)">Start</see>
/// </summary>
public void Start(string zoneId = null, string contextId = null)
{
if (log.IsDebugEnabled) log.Debug($"Started Consumer to wait for SIF Events of type {TypeName}.");
try
{
// Register the Event Consumer with the SIF Broker.
RegistrationService.Register(ref environment);
// Retrieve the Subscription identifier (if exist).
string subscriptionId = SessionsManager.ConsumerSessionService.RetrieveSubscriptionId(
Environment.ApplicationInfo.ApplicationKey,
Environment.SolutionId,
Environment.UserToken,
Environment.InstanceId);
// If the Subscription identifier does NOT exist, create a Subscription and associated Queue.
if (string.IsNullOrWhiteSpace(subscriptionId))
{
// For the SIF Broker, the name property is a mandatory.
queueType queue = new queueType
{
name = $"{TypeName}-event-consumer"
};
Queue = CreateQueue(queue);
subscriptionType subscription = new subscriptionType()
{
contextId = contextId,
queueId = Queue.id,
serviceName = $"{TypeName}s",
serviceType = ServiceType.OBJECT.ToDescription(),
zoneId = zoneId
};
Subscription = CreateSubscription(subscription);
// Store Queue and Subscription identifiers.
SessionsManager.ConsumerSessionService.UpdateQueueId(
Queue.id,
Environment.ApplicationInfo.ApplicationKey,
Environment.SolutionId,
Environment.UserToken,
Environment.InstanceId);
SessionsManager.ConsumerSessionService.UpdateSubscriptionId(
Subscription.id,
Environment.ApplicationInfo.ApplicationKey,
Environment.SolutionId,
Environment.UserToken,
Environment.InstanceId);
}
// If the Subscription identifier does exist, retrieve the Queue.
else
{
try
{
string queueId = SessionsManager.ConsumerSessionService.RetrieveQueueId(
Environment.ApplicationInfo.ApplicationKey,
Environment.SolutionId,
Environment.UserToken,
Environment.InstanceId);
Queue = RetrieveQueue(queueId);
}
catch (Exception e)
{
string errorMessage = $"Could not retrieve Queue details due to the following error:\n{e.GetBaseException().Message}.";
if (log.IsErrorEnabled) log.Error($"{errorMessage}\n{e.StackTrace}");
throw e;
}
}
// Manage SIF Events using background tasks.
cancellationTokenSource = new CancellationTokenSource();
CancellationToken cancellationToken = cancellationTokenSource.Token;
task = Task.Factory.StartNew(
() => ProcessEvents(cancellationToken),
cancellationToken,
TaskCreationOptions.LongRunning,
TaskScheduler.Default);
}
catch (RegistrationException e)
{
string errorMessage = $"Error registering the Event Consumer:\n{e.GetBaseException().Message}.\n{e.StackTrace}";
if (log.IsErrorEnabled) log.Error(e, errorMessage);
throw e;
}
catch (Exception e)
{
string errorMessage = $"Error starting the Event Consumer:\n{e.GetBaseException().Message}.\n{e.StackTrace}";
if (log.IsErrorEnabled) log.Error(e, errorMessage);
throw e;
}
}
/// <summary>
/// Serialise a queueType object.
/// </summary>
/// <param name="queue">queueType object.</param>
/// <returns>XML string representation of the queueType object.</returns>
private string SerialiseQueue(queueType queue)
{
return SerialiserFactory.GetXmlSerialiser<queueType>().Serialise(queue);
}
/// <summary>
/// Serialise a queueType object.
/// </summary>
/// <param name="queue">queueType object.</param>
/// <returns>String representation of the queueType object.</returns>
private string SerialiseQueue(queueType queue)
{
return(SerialiserFactory.GetSerialiser <queueType>(ContentType).Serialise(queue));
}
