/// <summary>
/// Initializes a new instance of the <see cref="CommittedExternalEvent"/> class.
/// </summary>
/// <param name="eventLogSequenceNumber">The event log sequence number of the Event.</param>
/// <param name="occurred">The <see cref="DateTimeOffset"/> when the Event was committed to the Event Store.</param>
/// <param name="eventSourceId">The <see cref="EventSourceId"/> of the Event.</param>
/// <param name="executionContext">The <see cref="ExecutionContext"/> in which the Event was committed.</param>
/// <param name="externalEventLogSequenceNumber">The event log sequence number of the Event in the event log of the external Microservice that committed the event.</param>
/// <param name="received">The <see cref="DateTimeOffset"/> when the Event was received over the Event Horizon.</param>
/// <param name="event">An instance of the Event that was committed to the Event Store.</param>
public CommittedExternalEvent(
EventLogSequenceNumber eventLogSequenceNumber,
DateTimeOffset occurred,
EventSourceId eventSourceId,
ExecutionContext executionContext,
EventLogSequenceNumber externalEventLogSequenceNumber,
DateTimeOffset received,
IEvent @event)
: base(eventLogSequenceNumber, occurred, eventSourceId, executionContext, @event)
{
ExternalEventLogSequenceNumber = externalEventLogSequenceNumber;
Received = received;
}
/// <summary>
/// Initializes a new instance of the <see cref="CommittedAggregateEvent"/> class.
/// </summary>
/// <param name="eventLogSequenceNumber">The event log sequence number of the Event.</param>
/// <param name="occurred">The <see cref="DateTimeOffset" /> when the Event was committed to the Event Store.</param>
/// <param name="eventSourceId">The <see cref="EventSourceId" /> of the Event.</param>
/// <param name="aggregateRoot">The <see cref="Type"/> of the Aggregate Root that applied the Event to the Event Source.</param>
/// <param name="aggregateRootVersion">The version of the <see cref="AggregateRoot"/> that applied the Event.</param>
/// <param name="executionContext">The <see cref="ExecutionContext"/> in which the Event was committed.</param>
/// <param name="event">An instance of the Event that was committed to the Event Store.</param>
public CommittedAggregateEvent(
EventLogSequenceNumber eventLogSequenceNumber,
DateTimeOffset occurred,
EventSourceId eventSourceId,
Type aggregateRoot,
AggregateRootVersion aggregateRootVersion,
ExecutionContext executionContext,
IEvent @event)
: base(eventLogSequenceNumber, occurred, eventSourceId, executionContext, @event)
{
AggregateRoot = aggregateRoot;
AggregateRootVersion = aggregateRootVersion;
}
/// <summary>
/// Initializes a new instance of the <see cref="EventContext"/> class.
/// </summary>
/// <param name="sequenceNumber">The <see cref="EventLogSequenceNumber">sequence number</see> that uniquely identifies the event in the event log which it was committed.</param>
/// <param name="eventSourceId">The <see cref="EventSourceId"/> that the event was committed to.</param>
/// <param name="occurred">The <see cref="DateTimeOffset"/> when the event was committed to the <see cref="IEventStore"/>.</param>
/// <param name="executionContext">The <see cref="ExecutionContext"/> in which the event was committed to the <see cref="IEventStore"/>.</param>
public EventContext(
EventLogSequenceNumber sequenceNumber,
EventSourceId eventSourceId,
DateTimeOffset occurred,
ExecutionContext executionContext)
: this(
sequenceNumber,
eventSourceId,
occurred,
executionContext,
new EventIdentifier(executionContext.Microservice, executionContext.Tenant, sequenceNumber))
{
}
/// <summary>
/// Initializes a new instance of the <see cref="EventContext"/> class.
/// </summary>
/// <param name="sequenceNumber">The <see cref="EventLogSequenceNumber">sequence number</see> that uniquely identifies the event in the event log which it was committed.</param>
/// <param name="eventSourceId">The <see cref="EventSourceId"/> that the event was committed to.</param>
/// <param name="occurred">The <see cref="DateTimeOffset"/> when the event was committed to the <see cref="IEventStore"/>.</param>
/// <param name="executionContext">The <see cref="ExecutionContext"/> in which the event was committed to the <see cref="IEventStore"/>.</param>
/// <param name="uniqueIdentifier">The <see cref="EventIdentifier"/> that uniquely identifies the event.</param>
protected EventContext(
EventLogSequenceNumber sequenceNumber,
EventSourceId eventSourceId,
DateTimeOffset occurred,
ExecutionContext executionContext,
EventIdentifier uniqueIdentifier)
{
SequenceNumber = sequenceNumber;
EventSourceId = eventSourceId;
Occurred = occurred;
ExecutionContext = executionContext;
UniqueIdentifier = uniqueIdentifier;
}
/// <summary>
/// Initializes a new instance of the <see cref="CommittedEvent"/> class.
/// </summary>
/// <param name="eventLogSequenceNumber">The event log sequence number of the Event.</param>
/// <param name="occurred">The <see cref="DateTimeOffset" /> when the Event was committed to the Event Store.</param>
/// <param name="eventSourceId">The <see cref="EventSourceId" /> of the Event.</param>
/// <param name="executionContext">The <see cref="ExecutionContext"/> in which the Event was committed.</param>
/// <param name="event">An instance of the Event that was committed to the Event Store.</param>
public CommittedEvent(
EventLogSequenceNumber eventLogSequenceNumber,
DateTimeOffset occurred,
EventSourceId eventSourceId,
ExecutionContext executionContext,
IEvent @event)
{
EventLogSequenceNumber = eventLogSequenceNumber;
Occurred = occurred;
ExecutionContext = executionContext;
Event = @event;
EventSource = eventSourceId;
}
/// <summary>
/// Initializes a new instance of the <see cref="ExternalEventContext"/> class.
/// </summary>
/// <param name="sequenceNumber">The <see cref="EventLogSequenceNumber">sequence number</see> that uniquely identifies the event in the event log which it was received.</param>
/// <param name="eventSourceId">The <see cref="EventSourceId"/> that the event was committed to.</param>
/// <param name="occurred">The <see cref="DateTimeOffset"/> when the event was committed to the <see cref="IEventStore"/>.</param>
/// <param name="executionContext">The <see cref="ExecutionContext"/> in which the event was committed to the <see cref="IEventStore"/>.</param>
/// <param name="externalEventLogSequenceNumber">The <see cref="EventLogSequenceNumber">sequence number</see> that uniquely identifies the event in the event log which it was committed (the external Microservice event log).</param>
/// <param name="received">The <see cref="DateTimeOffset"/> when the Event was received over the Event Horizon.</param>
public ExternalEventContext(
EventLogSequenceNumber sequenceNumber,
EventSourceId eventSourceId,
DateTimeOffset occurred,
ExecutionContext executionContext,
EventLogSequenceNumber externalEventLogSequenceNumber,
DateTimeOffset received)
: base(
sequenceNumber,
eventSourceId,
occurred,
executionContext,
new EventIdentifier(executionContext.Microservice, executionContext.Tenant, externalEventLogSequenceNumber))
{
ExternalEventLogSequenceNumber = externalEventLogSequenceNumber;
Received = received;
}
/// <summary>
/// Composes an event identifier <see cref="string"/> from its components.
/// </summary>
/// <param name="microservice">The <see cref="Microservice"/> that committed the event.</param>
/// <param name="tenant">The <see cref="TenantId"/> that committed the event.</param>
/// <param name="sequenceNumber">The <see cref="EventLogSequenceNumber"/> of the event that was committed.</param>
/// <returns>An event identifier <see cref="string"/>.</returns>
/// <remarks>
/// The event identifier string is the Base64 encoding of the concatenated bytes of the microservice ++ tenant ++ event log sequence number (40 bytes total).
/// When converting the values to bytes, they are in the order that they are transmitted over gRPC as defined by the contracts - i.e. little endian.
/// </remarks>
public static string Compose(Microservice microservice, TenantId tenant, EventLogSequenceNumber sequenceNumber)
{
var microserviceBytes = microservice.Value.ToByteArray();
var tenantBytes = tenant.Value.ToByteArray();
var sequenceNumberBytes = BitConverter.GetBytes(sequenceNumber.Value);
if (!BitConverter.IsLittleEndian)
{
Array.Reverse(sequenceNumberBytes);
}
using var stream = new MemoryStream(40);
stream.Write(microserviceBytes);
stream.Write(tenantBytes);
stream.Write(sequenceNumberBytes);
return(Convert.ToBase64String(stream.ToArray()));
}
/// <summary>
/// Initializes a new instance of the <see cref="EventLogSequenceNumberIsOutOfOrder"/> class.
/// </summary>
/// <param name="sequenceNumber">The <see cref="EventLogSequenceNumber"/> the Event was committed to.</param>
/// <param name="expectedSequenceNumber">Expected <see cref="EventLogSequenceNumber"/>.</param>
public EventLogSequenceNumberIsOutOfOrder(EventLogSequenceNumber sequenceNumber, EventLogSequenceNumber expectedSequenceNumber)
: base($"Event Log Sequence is out of order because Event Log Sequence Number '{sequenceNumber}' is not greater than '{expectedSequenceNumber}'.")
{
}
/// <summary>
/// Tries to decompose an event identifier <see cref="string"/> to its components.
/// </summary>
/// <param name="eventIdentifier">The event identifier <see cref="string"/>.</param>
/// <param name="microservice">When this method returns, the <see cref="Microservice"/> that committed the event.</param>
/// <param name="tenant">When this method returns, the <see cref="TenantId"/> that committed the event.</param>
/// <param name="sequenceNumber">When this method returns, the <see cref="EventLogSequenceNumber"/> of the event that was committed.</param>
/// <returns><c>true</c> if the deomposition was successful; otherwise, <c>false</c>.</returns>
public static bool TryDecompose(string eventIdentifier, out Microservice microservice, out TenantId tenant, out EventLogSequenceNumber sequenceNumber)
{
var decoded = new Span <byte>(new byte[40]);
if (Convert.TryFromBase64String(eventIdentifier, decoded, out var read) && read == 40)
{
var microserviceBytes = decoded.Slice(0, 16);
var tenantBytes = decoded.Slice(16, 16);
var sequenceNumberBytes = decoded.Slice(32, 8);
if (!BitConverter.IsLittleEndian)
{
sequenceNumberBytes.Reverse();
}
microservice = new Guid(microserviceBytes);
tenant = new Guid(tenantBytes);
sequenceNumber = BitConverter.ToUInt64(sequenceNumberBytes);
return(true);
}
microservice = null;
tenant = null;
sequenceNumber = 0;
return(false);
}
/// <summary>
/// Initializes a new instance of the <see cref="EventIdentifier"/> class.
/// </summary>
/// <param name="microservice">The <see cref="Microservice"/> that committed the event.</param>
/// <param name="tenant">The <see cref="TenantId"/> that committed the event.</param>
/// <param name="sequenceNumber">The <see cref="EventLogSequenceNumber"/> of the event that was committed.</param>
public EventIdentifier(Microservice microservice, TenantId tenant, EventLogSequenceNumber sequenceNumber)
{
Value = Compose(microservice, tenant, sequenceNumber);
}
/// <summary>
/// Decomposes the <see cref="EventIdentifier"/> to its components.
/// </summary>
/// <param name="microservice">When this method returns, the <see cref="Microservice"/> that committed the event.</param>
/// <param name="tenant">When this method returns, the <see cref="TenantId"/> that committed the event.</param>
/// <param name="sequenceNumber">When this method returns, the <see cref="EventLogSequenceNumber"/> of the event that was committed.</param>
public void Decompose(out Microservice microservice, out TenantId tenant, out EventLogSequenceNumber sequenceNumber)
{
TryDecompose(Value, out microservice, out tenant, out sequenceNumber);
}