Simple PowerShell Example

[DarioCalovic]

I am trying to get a simple example running on PowerShell. My gut is telling me, that i am doing something wrong with the EventHandler. All I am getting is a Exception calling "Request" with "3" argument(s): "Timeout occurred.". Any thoughts?

PowerShell Example

Import-Module "NATS.Client.dll"

$cf = New-Object NATS.Client.ConnectionFactory;

$servers = @(
    'nats://example-nats:4222'
)

$opts = [NATS.Client.ConnectionFactory]::GetDefaultOptions();
$opts.MaxReconnect = 2;
$opts.ReconnectWait = 1000;
$opts.Servers = $servers;
$opts.user = 'user'
$opts.password = 'secret'

$opts.AsyncErrorEventHandler += {
	param(
		[object]$sender,
		[NATS.Client.ErrEventArgs]$args
	) 
	Write-Host "error"
}

$c = $cf.CreateConnection($opts);

[System.EventHandler[NATS.Client.MsgHandlerEventArgs]] $h = {
	param(
		[object]$sender,
		[NATS.Client.MsgHandlerEventArgs]$args
	) 
	
	Write-Host "bar"
	
	# Reply
	$replyMsg = New-Object NATS.Client.Msg;
	$replyMsg.Data = [System.Text.Encoding]::UTF8.GetBytes("reply")
	$replyMsg.Subject = $args.Message.Reply;
	$c.Publish($replyMsg);
	$c.Flush();
}


[NATS.Client.IAsyncSubscription] $s = $c.SubscribeAsync("foo", $h)
# $s.Add_MessageHandler($h)
# $s.Start();

$m = $c.Request("foo", [System.Text.Encoding]::UTF8.GetBytes("hello world"), 2000);

$s.Unsubscribe();

# Draining and closing a connection
$c.Drain();

# Closing a connection
$c.Close();

C# Example

// Create a new connection factory to create
// a connection.
ConnectionFactory cf = new ConnectionFactory();

// Creates a live connection to the default
// NATS Server running locally
IConnection c = cf.CreateConnection();

// Setup an event handler to process incoming messages.
// An anonymous delegate function is used for brevity.
EventHandler<MsgHandlerEventArgs> h = (sender, args) =>
{
    // print the message
    Console.WriteLine(args.Message);

    // Here are some of the accessible properties from
    // the message:
    // args.Message.Data;
    // args.Message.Reply;
    // args.Message.Subject;
    // args.Message.ArrivalSubcription.Subject;
    // args.Message.ArrivalSubcription.QueuedMessageCount;
    // args.Message.ArrivalSubcription.Queue;

    // Unsubscribing from within the delegate function is supported.
    args.Message.ArrivalSubcription.Unsubscribe();
};

// The simple way to create an asynchronous subscriber
// is to simply pass the event in.  Messages will start
// arriving immediately.
IAsyncSubscription s = c.SubscribeAsync("foo", h);

// Alternatively, create an asynchronous subscriber on subject foo,
// assign a message handler, then start the subscriber.   When
// multicasting delegates, this allows all message handlers
// to be setup before messages start arriving.
IAsyncSubscription sAsync = c.SubscribeAsync("foo");
sAsync.MessageHandler += h;
sAsync.Start();

// Simple synchronous subscriber
ISyncSubscription sSync = c.SubscribeSync("foo");

// Using a synchronous subscriber, gets the first message available,
// waiting up to 1000 milliseconds (1 second)
Msg m = sSync.NextMessage(1000);

c.Publish("foo", Encoding.UTF8.GetBytes("hello world"));

// Unsubscribing
sAsync.Unsubscribe();

// Publish requests to the given reply subject:
c.Publish("foo", "bar", Encoding.UTF8.GetBytes("help!"));

// Sends a request (internally creates an inbox) and Auto-Unsubscribe the
// internal subscriber, which means that the subscriber is unsubscribed
// when receiving the first response from potentially many repliers.
// This call will wait for the reply for up to 1000 milliseconds (1 second).
m = c.Request("foo", Encoding.UTF8.GetBytes("help"), 1000);

// Draining and closing a connection
c.Drain();

// Closing a connection
c.Close();

[DarioCalovic]

I've got it with the Sync example:

While($True) {
    [NATS.Client.Msg] $m = $sSync.NextMessage(-1);
    Write-Host $m;

    # Invoke PowerShell Script from config

    # REPLY
    $replyMsg = New-Object NATS.Client.Msg;
	$replyMsg.Data = [System.Text.Encoding]::UTF8.GetBytes("reply")
	$replyMsg.Subject = $m.Reply;
	$c.Publish($replyMsg);
	$c.Flush();

}

[scottf]

The timeout suggests that there is no subscriber to receive the request. How / does powershell hold onto / keep alive the subscription [object] you made or does it just go away by the next statement?

[scottf]

@DarioCalovic Moved to .net client discussion