/// <summary>
/// This method creates the command handler. You can override this method to set additional properties.
/// </summary>
/// <param name="holder">The command holder</param>
/// <returns>Returns the handler.</returns>
protected virtual H CommandHandlerCreate(CommandHolder holder)
{
var handler = new H();
handler.Initialise(holder);
return(handler);
}
/// <summary>
/// This method will notify the command container when a commands is added or removed.
/// </summary>
/// <param name="key">The key.</param>
/// <param name="remove">Set this to true to remove the command mapping, false is default.</param>
protected virtual void CommandNotify(CommandHolder key, bool remove = false, bool isQuorum = false)
{
try
{
OnCommandChange?.Invoke(this, new CommandChange(remove, key.Message, isQuorum));
}
catch (Exception ex)
{
Logger?.LogException($"Command {GetType().Name} Change Notification failed", ex);
}
}
/// <summary>
/// This method scans through the command and registers commands that are defined using the metadata tags.
/// </summary>
protected virtual void CommandsRegisterReflection()
{
foreach (var signature in this.CommandMethodAttributeSignatures(true))
{
var handler = new CommandHolder(CommandChannelAdjust(signature.Item1)
, (rq, rs) => signature.Item2.Action(rq, rs, PayloadSerializer)
, referenceId: signature.Item3);
CommandRegister(handler);
}
}
/// <summary>
/// This method is used to register a command holder for a particular method.
/// </summary>
/// <param name="cHolder">The holder.</param>
protected void CommandRegister(CommandHolder cHolder)
{
mSupported.Add(cHolder, CommandHandlerCreate(cHolder));
switch (mPolicy.CommandNotify)
{
case CommandNotificationBehaviour.OnRegistration:
CommandNotify(cHolder, false);
break;
case CommandNotificationBehaviour.OnRegistrationIfStarted:
if (Status == ServiceStatus.Running)
{
CommandNotify(cHolder, false);
}
break;
}
}
/// <summary>
/// This method registers a particular command.
/// </summary>
/// <param name="channelId">The message channelId</param>
/// <param name="messageType">The command channelId</param>
/// <param name="actionType">The command action</param>
/// <param name="command">The action delegate to execute.</param>
protected void CommandRegister(MessageFilterWrapper key,
Func <TransmissionPayload, List <TransmissionPayload>, Task> action,
Func <TransmissionPayload, List <TransmissionPayload>, Task> deadLetterAction = null,
Func <Exception, TransmissionPayload, List <TransmissionPayload>, Task> exceptionAction = null)
{
if (key == null)
{
throw new ArgumentNullException("CommandRegister: key cannot be null");
}
Func <TransmissionPayload, List <TransmissionPayload>, Task> command = async(rq, rs) =>
{
bool error = false;
Exception actionEx = null;
try
{
//Depending on the message type, execute the deadletter action.
if (rq.IsDeadLetterMessage && deadLetterAction != null)
{
await deadLetterAction(rq, rs);
}
else
{
await action(rq, rs);
}
}
catch (Exception ex)
{
if (exceptionAction == null)
{
throw;
}
error = true;
actionEx = ex;
}
try
{
if (error)
{
await exceptionAction(actionEx, rq, rs);
}
}
catch (Exception ex)
{
throw;
}
};
if (key.Header.IsPartialKey && key.Header.ChannelId == null)
{
throw new Exception("You must supply a channel when using a partial key.");
}
var cHolder = new CommandHolder(key);
mSupported.Add(cHolder, CommandHandlerCreate(key, command));
switch (mPolicy.CommandNotify)
{
case CommandNotificationBehaviour.OnRegistration:
CommandNotify(cHolder, false);
break;
case CommandNotificationBehaviour.OnRegistrationIfStarted:
if (Status == ServiceStatus.Running)
{
CommandNotify(cHolder, false);
}
break;
}
}
/// <summary>
/// This is the constructor for registering a manual command.
/// </summary>
/// <param name="message">The message filter wrapper route to identify the command.</param>
/// <param name="command">The command to process.</param>
/// <param name="referenceId">The optional reference id for tracking.</param>
public CommandInline(MessageFilterWrapper message
, Func <TransmissionPayload, List <TransmissionPayload>, IPayloadSerializationContainer, Task> command
, string referenceId = null) : base(null)
{
mCommandHolder = new CommandHolder(message, async(rq, rs) => await command(rq, rs, PayloadSerializer), referenceId);
}
/// <summary>
/// This method initialises the holder.
/// </summary>
/// <param name="parent">The name of the parent container.</param>
/// <param name="key"></param>
/// <param name="action"></param>
public virtual void Initialise(CommandHolder holder)
{
Key = holder.Message;
Action = holder.Command;
}