I have singleton azure-redis database client used in our application. However on Azure portal it shows connected clients 4.99K. I am not sure who are those clients and why it is showing 4.99K clients connected when I have singleton instance?
Sample Code:
using StackExchange.Redis;
if (instance == null)
{
lock (syncRoot)
{
if (instance == null)
{
try
{
_cacheService = GetConnectionMultiplexer();
instance = _cacheService.GetDatabase();
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
}
}
}
}
Per our discussion in comments, this is the same issue as described here:
Why are connections to Azure Redis Cache so high?
Related
I'm new to JMS and am trying to setup Apache Active MQ for a messaging application as an alternative to Azure Service Bus that I'm very familiar with. I would like to setup topics and durable subscribers as and administrative task, and would like the runtime process to consume messages from those existing durable subscriber only based upon its name and, possibly, client id.
How do I retrieve an existing durable subscriber, without knowing the selector?
All the documentation and the samples I've read show that the only way to consume a message is to call the session.createDurableSubscriber() method.
Additionaly, I prefer to use the AMQP abstraction over JMS. So I found the following code to retrieve an existing subscriber:
public static ReceiverLink RecoverDurableSource(Session session, string topicPath, string subscriptionName)
{
Source recovered = null;
using (var attached = new ManualResetEvent(false))
{
void OnAttached(ILink link, Attach Attach)
{
recovered = (Source)Attach.Source;
attached.Set();
}
ReceiverLink receiver = null;
try
{
receiver = new ReceiverLink(session, subscriptionName, (Source)null, OnAttached);
if (!attached.WaitOne(TimeSpan.FromSeconds(5)))
return null;
CloseReceiverLink(receiver);
return recovered != null
? new ReceiverLink(session, subscriptionName, recovered, null)
: null
;
}
finally
{
if (recovered == null)
CloseReceiverLink(receiver);
}
}
}
private static void CloseReceiverLink(ReceiverLink receiver)
{
if (receiver == null)
return;
if (receiver.Error == null || Equals(receiver.Error.Condition, new Symbol("amqp:not-found")))
receiver.Close();
}
However, this code has the nasty side effect to re-create and default durable subscriber (manifested in this code by the ReceiverLink object) with the same name and then, if it exists, re-creating it with the correct Sourceobject.
But this may disrupt the reception of messages at the time this method is called.
I created an Edge browser extension which uses Native Messaging to a native app running via a Desktop Bridge technology. I used the SecureInput as a sample, which contains the Edge extension, UWP host and a Win32 Desktop Bridge app.
I need the Win32 Desktop Bridge app to connect to a web service using HTTP and WebSocket, so I added an internetClientServer and a privateNetworkClientServer capabilities to the package manifest, beside the already existed runFullTrust one.
The Win32 Desktop Bridge app activates just fine, and it is able to connect to the web server using HTTP. But as soon as it tries to open a WebSocket connection, the BackgroundTaskInstance on the UWP host receives a cancellation request with a BackgroundTaskCancellationReason.SystemPolicy as a reason, and the Desktop Bridge application closes. Unfortunately, the documentation for the BackgroundTaskCancellationReason.SystemPolicy does not explain much about true reasons of the cancellation request.
I tried to use two WebSocket classes: the System.Net.WebSockets.ClientWebSocket and the Windows.Networking.Sockets.MessageWebSocket, with the same result. No fancy code, just regular
var socket = new MessageWebSocket();
...
await socket.ConnectAsync(new Uri("wss://127.0.0.1:9001/myservice"));
The same WebSocket service endpoint is available from other WS clients, so I guess there is no server/firewall/antivirus issue here.
I also played with the CheckNetIsolation tool, adding loopback exemption for the Edge browser and for the package, with no effect. The HTTP works fine without the loopback exemption.
What may be a true reason of the task cancellation, and what can be a possible way to prevent it?
Ok, I resolved the issue. Thanks to this comment by Tom Shane I stumbled upon, I realized that the BackgroundTaskCancellationReason.SystemPolicy tells that the background task is closed by the system to release some system resources, and that in my case it happened because I didn't obtain a deferral in my async event handler. When the event handler yielded without a deferral, the system decided it can shut the task down. Below is a digested version of the code:
static class Program
{
static AppServiceConnection connection = null;
[STAThread]
static void Main(string[] args)
{
Thread appServiceThread = new Thread(new ThreadStart(ThreadProc));
appServiceThread.Start();
Application.Run();
}
static async void ThreadProc()
{
try {
connection = new AppServiceConnection();
connection.AppServiceName = "...";
connection.PackageFamilyName = Windows.ApplicationModel.Package.Current.Id.FamilyName;
connection.RequestReceived += OnRequestReceived;
connection.ServiceClosed += OnServiceClosed;
var status = await connection.OpenAsync();
....
}
catch (Exception e) { ... }
}
private static async void OnRequestReceived(AppServiceConnection sender, AppServiceRequestReceivedEventArgs args)
{
var defer = args.GetDeferral(); // <== that was missing, rookie mistake!
try {
var msg = ParseMessage(args.Request.Message);
if (msg.type.Equals("ws")) {
// this method was truly async
// and every time it yielded the issue was revealed
await HandleWsMessage(request, msg);
}
else if (msg.type.Equals("http")) {
// but this method was actually synchronous despite being marked as "async"
// and it never yielded, masking the issue for HTTP client
await HandleHttpMessage(request, msg);
}
}
catch (Exception e) { ... }
finally {
defer.Complete();
}
}
}
I am having difficulty with a chatbot that I developed which works fine locally but after it was deployed to dev.botframework.com it does not appear to work.
My code is below and it breaks at the line...
await Conversation.SendAsync(activity, () => new MyBot.AppServices.ServiceLUIS()); where it states
{"Authorization for Microsoft App ID a8641a16-932c-49a5-af8b-a58ab2ce251f failed with status code Unauthorized and reason phrase 'Unauthorized'"}.
I have tried the instructions at Troubleshooting Bot Framework Authentication with the following results:
Step 1: Connect without password on localhost - Worked fine!
Step 2: Verify AppID and Password are Correct - They are!
Step 3: Enable security and run on localhost - This does not work :( However the endpoint is correct as are the MicrosoftAppID and Password
Step 4: Connect to your bot using the Bot Framework Developer Portal - This also works! However when using the web chat feature within the portal I also get an internal server error
Where it is breaking is on a call to my LUIS service so to me it seems like my Bot doesn't have authorization to call my LUIS model. However I can't seem to find anything in Azure where my bot is published and LUIS Model resides where I would allow LUIS model to authorize access to my BOT. Also don't see anything in Luis.ai or Bot Framework Portal.
Any ideas on how best to resolve would really be helpful!
namespace MyBot
{
[BotAuthentication]
public class MessagesController : ApiController
{
/// <summary>
/// POST: api/Messages
/// Receive a message from a user and reply to it
/// </summary>
public async Task<HttpResponseMessage> Post([FromBody]Activity activity)
{
try
{
if (activity.Type == ActivityTypes.Message)
{
**await Conversation.SendAsync(activity, () => new MyBot.AppServices.ServiceLUIS());**
}
else
{
ConnectorClient connector = new ConnectorClient(new Uri(activity.ServiceUrl));
var reply = HandleSystemMessage(activity);
if (reply != null)
await connector.Conversations.ReplyToActivityAsync(reply);
HandleSystemMessage(activity);
}
var response = Request.CreateResponse(HttpStatusCode.OK);
return response;
}
catch (Exception e)
{
return null;
}
}
private Activity HandleSystemMessage(Activity message)
{
if (message.Type == ActivityTypes.DeleteUserData)
{
// Implement user deletion here
// If we handle user deletion, return a real message
}
else if (message.Type == ActivityTypes.ConversationUpdate)
{
// Handle conversation state changes, like members being added and removed
// Use Activity.MembersAdded and Activity.MembersRemoved and Activity.Action for info
// Not available in all channels
}
else if (message.Type == ActivityTypes.ContactRelationUpdate)
{
// Handle add/remove from contact lists
// Activity.From + Activity.Action represent what happened
}
else if (message.Type == ActivityTypes.Typing)
{
// Handle knowing tha the user is typing
}
else if (message.Type == ActivityTypes.Ping)
{
}
return null;
}
}
}
Solved! Ended up creating another new key and password for the bot and republishing and it worked! –
I want to get the Queue Depth for a Transmission Queue (XMIT queue) using WebSphere MQ Classes for .Net , can someone kindly help me giving a specific link/Pseudocode or .Net Classes/API to identify the XMIT queue depth. I have gone through the .Net API but didn't find any info on XMIT queue.
You can use the MQ .NET PCF interface to query queue attributes. Below is the sample code snippet.
Note: MQ .NET PCF interface is undocumented interface and may not be supported. You will need to consult IBM.
public static void InquireQueue()
{
PCFMessageAgent messageAgent = null;
try
{
// Create connection to queue manager
messageAgent = new PCFMessageAgent("QM3");
// Build Inquire command to query attributes a queue
PCFMessage pcfMsg = new PCFMessage(MQC.MQCMD_INQUIRE_Q);
pcfMsg.AddParameter(MQC.MQCA_Q_NAME, "TO.QM2");
// Send request and receive response
PCFMessage[] pcfResponse = messageAgent.Send(pcfMsg);
// Process and print response.
int pcfResponseLen = pcfResponse.Length;
for (int pcfResponseIdx = 0; pcfResponseIdx < pcfResponseLen; pcfResponseIdx++)
{
PCFParameter[] parameters = pcfResponse[pcfResponseIdx].GetParameters();
foreach (PCFParameter pm in parameters)
{
// We just want to print current queue depth only
if (pm.Parameter == MQC.MQIA_CURRENT_Q_DEPTH)
Console.WriteLine("Queue Depth" + " - " + pm.GetValue());
}
}
}
catch (PCFException pcfEx)
{
Console.Write(pcfEx);
}
catch (MQException ex)
{
Console.Write(ex);
}
finally
{
if (messageAgent != null)
messageAgent.Disconnect();
}
}
Is there any direct way to check if a Cluster/Session is connected/valid/ok?
I mean, I have a com.datastax.driver.core.Session created into a neverending thread and I'd like to assure the session is ok every time is needed. I use the next cluster initialization, but I'm not sure this is enough...
Cluster.builder().addContactPoint(url)
.withRetryPolicy(DowngradingConsistencyRetryPolicy.INSTANCE)
.withReconnectionPolicy(new ConstantReconnectionPolicy(1000L)).build());
In fact when using the DataStax Java Driver, you have a hidden/magic capability embedded:
The driver is aware of the full network topology (nodes topology across datacenters and nodes availabilities).
Thus, the only thing you have to do is to initialise your cluster with a few nodes(1) and then you can be sure at every moment that if there is at least one available node your request will be performed correctly. Because the driver is topology aware, if one node (even initialisation nodes) goes out of availability, the driver will automagically route your request to another available node.
In summary, your code is good(1).
(1): You should provide a few nodes in order to be fault tolerant in the cluster initialisation phase. Indeed, if one initialisation node is down, the driver has then the possibility to contact another one to discover the full topology.
I have a local development environment setup where I am starting up my java application and Cassandra (Docker) container at the same time, so Cassandra will normally not be in a ready state when the java application first attempts to connect.
When this is starting up the application will throw a NoHostAvailableException when the Cluster instance attempts to create a Session. Subsequent attempts to create a Session from the Cluster will then throw an IllegalStateException because the cluster instance was closed after the first exception.
What I did to rememdy this was to create a check method that attempts to create a Cluster and Session and then immediately closes these. See this:
private void waitForCassandraToBeReady(String keyspace, Cluster.Builder builder) {
RuntimeException exception = null;
int retries = 0;
while (retries++ < 40) {
Session session = null;
Cluster cluster = null;
try {
cluster = builder.build();
session = cluster.connect(keyspace);
log.info("Cassandra is available");
return;
} catch (RuntimeException e) {
log.warn("Cassandra not available, try {}", retries);
exception = e;
} finally {
if (session != null && !session.isClosed()) session.close();
if (cluster != null && !cluster.isClosed()) cluster.close();
}
sleep();
}
log.error("Retries exceeded waiting for Cassandra to be available");
if (exception != null) throw exception;
else throw new RuntimeException("Cassandra not available");
}
After this method returns, I then create a create a Cluster and Session independent of this check method.