/// <summary>
/// Send a 'batch of <see cref="EventData"/> with the same partitionKey' to EventHub. All <see cref="EventData"/>'s with a partitionKey are guaranteed to land on the same partition.
/// Multiple PartitionKey's will be mapped to one Partition.
/// <para>
/// There are 3 ways to send to EventHubs, to understand this particular type of send refer to the overload <see cref="SendAsync(EventData, string)"/>,
/// which is the same type of send and is used to send single <see cref="EventData"/>.
/// </para>
/// Sending a batch of <see cref="EventData"/>'s is useful in the following cases:
/// <para>i. Efficient send - sending a batch of <see cref="EventData"/> maximizes the overall throughput by optimally using the number of sessions created to EventHubs service.</para>
/// <para>ii. Sending multiple events in One Transaction. This is the reason why all events sent in a batch needs to have same partitionKey (so that they are sent to one partition only).</para>
/// </summary>
/// <param name="eventDatas">the batch of events to send to EventHub</param>
/// <param name="partitionKey">the partitionKey will be hashed to determine the partitionId to send the EventData to. On the Received message this can be accessed at <see cref="EventData.SystemPropertiesCollection.PartitionKey"/>.</param>
/// <returns>A Task that completes when the send operation is done.</returns>
/// <seealso cref="SendAsync(EventData)"/>
/// <see cref="PartitionSender.SendAsync(EventData)"/>
public async Task SendAsync(IEnumerable <EventData> eventDatas, string partitionKey)
{
// eventDatas null check is inside ValidateEvents
int count = EventDataSender.ValidateEvents(eventDatas);
EventHubsEventSource.Log.EventSendStart(this.ClientId, count, partitionKey);
Activity activity = EventHubsDiagnosticSource.StartSendActivity(this.ClientId, this.ConnectionStringBuilder, partitionKey, eventDatas, count);
Task sendTask = null;
try
{
sendTask = this.InnerSender.SendAsync(eventDatas, partitionKey);
await sendTask.ConfigureAwait(false);
}
catch (Exception exception)
{
EventHubsEventSource.Log.EventSendException(this.ClientId, exception.ToString());
EventHubsDiagnosticSource.FailSendActivity(activity, this.ConnectionStringBuilder, partitionKey, eventDatas, exception);
throw;
}
finally
{
EventHubsEventSource.Log.EventSendStop(this.ClientId);
EventHubsDiagnosticSource.StopSendActivity(activity, this.ConnectionStringBuilder, partitionKey, eventDatas, sendTask);
}
}
/// <summary>
/// Send <see cref="EventData"/> to a specific EventHub partition. The targeted partition is pre-determined when this PartitionSender was created.
/// <para>
/// There are 3 ways to send to EventHubs, to understand this particular type of send refer to the overload <see cref="SendAsync(EventData)"/>, which is the same type of send and is used to send single <see cref="EventData"/>.
/// </para>
/// Sending a batch of <see cref="EventData"/>'s is useful in the following cases:
/// <para>i. Efficient send - sending a batch of <see cref="EventData"/> maximizes the overall throughput by optimally using the number of sessions created to EventHubs' service.</para>
/// <para>ii. Sending multiple <see cref="EventData"/>'s in a Transaction. To acheive ACID properties, the Gateway Service will forward all <see cref="EventData"/>'s in the batch to a single EventHub partition.</para>
/// </summary>
/// <example>
/// Sample code:
/// <code>
/// EventHubClient client = EventHubClient.Create("__connectionString__");
/// PartitionSender senderToPartitionOne = client.CreatePartitionSender("1");
///
/// while (true)
/// {
/// var events = new List<EventData>();
/// for (int count = 1; count < 11; count++)
/// {
/// var payload = new PayloadEvent(count);
/// byte[] payloadBytes = Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(payload));
/// var sendEvent = new EventData(payloadBytes);
/// var applicationProperties = new Dictionary<string, string>();
/// applicationProperties["from"] = "csharpClient";
/// sendEvent.Properties = applicationProperties;
/// events.Add(sendEvent);
/// }
///
/// await senderToPartitionOne.SendAsync(events);
/// Console.WriteLine("Sent Batch... Size: {0}", events.Count);
///
/// }
/// </code>
/// </example>
/// <param name="eventDatas">batch of events to send to EventHub</param>
/// <returns>a Task that completes when the send operation is done.</returns>
/// <exception cref="MessageSizeExceededException">the total size of the <see cref="EventData"/> exceeds a pre-defined limit set by the service. Default is 256k bytes.</exception>
/// <exception cref="EventHubsException">Event Hubs service encountered problems during the operation.</exception>
public async Task SendAsync(IEnumerable <EventData> eventDatas)
{
Guard.ArgumentNotNull(nameof(eventDatas), eventDatas);
if (eventDatas is EventDataBatch && !string.IsNullOrEmpty(((EventDataBatch)eventDatas).PartitionKey))
{
throw Fx.Exception.InvalidOperation(Resources.PartitionSenderInvalidWithPartitionKeyOnBatch);
}
int count = EventDataSender.ValidateEvents(eventDatas);
EventHubsEventSource.Log.EventSendStart(this.ClientId, count, null);
Activity activity = EventHubsDiagnosticSource.StartSendActivity(this.ClientId, this.EventHubClient.ConnectionStringBuilder, this.PartitionId, eventDatas, count);
Task sendTask = null;
try
{
sendTask = this.InnerSender.SendAsync(eventDatas, null);
await sendTask.ConfigureAwait(false);
}
catch (Exception exception)
{
EventHubsEventSource.Log.EventSendException(this.ClientId, exception.ToString());
EventHubsDiagnosticSource.FailSendActivity(activity, this.EventHubClient.ConnectionStringBuilder, this.PartitionId, eventDatas, exception);
throw;
}
finally
{
EventHubsEventSource.Log.EventSendStop(this.ClientId);
EventHubsDiagnosticSource.StopSendActivity(activity, this.EventHubClient.ConnectionStringBuilder, this.PartitionId, eventDatas, sendTask);
}
}