M2mqtt incorporate in my asp.net mvc project. Face problem to synch subscribe informations.
When more than one clients published on one specific topic, client can subscribe them easily.
suppose in one situation when published happen then client is down/offline when he alive then only get the last published message not all published messages.
What to do?Is it a problem on MQTT?How alive client get all published messages.
M2mqtt connection with broker use by bellow syntax
public static MqttClient SmartHomeMQTT { get; set; }
SmartHomeMQTT = new MqttClient(brokerAddress, MqttSettings.MQTT_BROKER_DEFAULT_SSL_PORT, true, new X509Certificate(Resource.ca), null, MqttSslProtocols.TLSv1_2, client_RemoteCertificateValidationCallback);
SmartHomeMQTT.Connect("6ea592c5-4b2f-481a-bb0a-eccbe8579d14", "####", "####", false, 3600);
**Note:**Connect method parameter four set to false for clean_session property but it's not work.
To ensure that subscribers receive all messages, even ones that are published when they are offline (known as message persistence), you need to do a few things:
Make sure that 'Clean Session' is turned off in the subscribers
Ensure that each subscriber is using a unique Client ID
Use a QoS of 1 or 2
You don't say which MQTT server you are using, but you need to ensure that the server implementation supports it too.
Related
I have to create calendar push notification but didn't undersatnd how to create channel subscription ?
private void perormWatch(Calendar service, String user) throws Exception {
Channel content = new Channel();
content.setId("abcd#gmail.com");
content.setType("web_hook");
content.setAddress("http://localhost:8888/calendarNotiication");
com.google.api.services.calendar.Calendar.CalendarList.Watch cal = service.calendarList().watch(content);
}
I assume that you want to set up a channel with CalendarList.watch(). To do so you must satisfy three minimum requirements:
An id that uniquely identifies this new channel within your project.
The type property set on web_hook
An address over HTTPS where you want to receive the notifications.
By keeping that in mind, you only have to update your script to match the requirements. First of all the address is set to an invalid URL in the example. It must start with https, not http. Please be aware that only valid SSL certificates are acceptable (i.e. not selfsigned certificates, revoked or badly formed). Also please check that the id is truly unique within your project. Those small modifications should suffice in the example code, but feel free to update your question and leave a comment if you need further solutions.
I'm using the new Symfony Messenger Component 4.1 and RabbitMQ 3.6.10-1 to queue and asynchronously send email and SMS notifications from my Symfony 4.1 web application. My Messenger configuration (messenger.yaml) looks like this:
framework:
messenger:
transports:
amqp: '%env(MESSENGER_TRANSPORT_DSN_NOTIFICATIONS)%'
routing:
'App\NotificationBundle\Entity\NotificationQueueEntry': amqp
When a new notification is to be sent, I queue it like this:
use Symfony\Component\Messenger\MessageBusInterface;
// ...
$notificationQueueEntry = new NotificationQueueEntry();
// [Set notification details such as recipients, subject, and message]
$this->messageBus->dispatch($notificationQueueEntry);
Then I start the consumer like this on the command line:
$ bin/console messenger:consume-messages
I have implemented a SendNotificationHandler service where the actual delivery happens. The service configuration:
App\NotificationBundle\MessageHandler\SendNotificationHandler:
arguments:
- '#App\NotificationBundle\Service\NotificationQueueService'
tags: [ messenger.message_handler ]
And the class:
class SendNotificationHandler
{
public function __invoke(NotificationQueueEntry $entry): void
{
$this->notificationQueueService->sendNotification($entry);
}
}
Until this point, everything works smoothly and the notifications get delivered.
Now my question: It may happen that an email or SMS cannot be delivered due to a (temporary) network failure. In such a case, I would like my system to retry the delivery after a specified amount of time, up to a specified maximum number of retries. What is the way to go to achieve this?
I have read about Dead Letter Exchanges, however, I could not find any documentation or example on how to integrate this with the Symfony Messenger Component.
What you need to do is tell RabbitMQ, that the message is rejected instead of acknowledged. By default the messenger will take care of this inside the AmqpReceiver. As you can see there, if you throw an exception that implements the RejectMessageExceptionInterface inside your handler, the message will automatically be rejected for you.
You could also "simulate" this behaviour with custom middleware. I created something like it, in a small demo application. The mechanism consists of a middleware that wraps the (serialized) original message inside a new RetryMessage and sends it via a custom message bus to a different queue, used as a dead letter exchange. The handler for that message will then unpack the RetryMessage (getting the original message and deserializing it) and transmit it over the default bus:
See:
RetryMessage
RetryMiddleware
messenger.yaml
RetryMessageHandler
This is a basic setup which rejects the message and allows you to consume it again instantly(!). You probably want to add additional information such as headers for timestamps when delaying the consumption to improve on this. For this you should look at writing your own receiver, middleware and/or handler.
In the signalr, for each tag that opens, the ConnectionId registers for the user.
I use the following code to send messages to users.
1
2
hubContext.Clients.Clients (user.ConnectionIds.ToLi st ()); receiveNotification (message, userID, link);
The problem I have is that I want to send a message to the user once, not to the number of ConnectionId.
How can I find one of its active ConnectionIds and just send that message?
Is there a better way?
I also worked on this link
https://stackoverflow.com/questions/...ovider-new-2-0
But because of
I do not use request.User.Identity.Name, this method does not work. I'm using my user id. I'm reading the table.
value of request.User.Identity.Name in my app is empty because i'm reading user information from table in database
Thanks for your advice
You can retain connection and user information in a Map that is stored in memory.
private readonly Dictionary<T, HashSet<string>> _connections =
new Dictionary<T, HashSet<string>>();
You can find the fulle example here :
https://learn.microsoft.com/en-us/aspnet/signalr/overview/guide-to-the-api/mapping-users-to-connections
I'm using Signalr for a realtime notifications for when you get a new message or friend request, and when you view them it changes a "HasBeenViewed" field to true in the database.
The problem is that when Signalr checks for new notifications it doesn't see the changed "HasBeenViewed" field, it thinks it is still false. In the database itself i can confirm that HasBeenViewed has been changed correctly.
The query in Signalr does correctly recognize if a new message/friend request has been added, or if one has been removed. It just doesn't see the updated value for HasBeenViewed.
If I restart IIS then it Signalr finally does see the updated HasBeenViewed value and displays the notifications correctly. However, if a new notification gets sent and viewed, then it is back to not recognizing the viewed status on the new notifications.
Here is my code for the notification check. Using ASP.NET Core. I'm querying from a repository to an MS SQL database.
public void NotificationCheck(string userName)
{
var user = _repo.Query<ApplicationUser>().Where(u => u.UserName == userName).Include(u => u.FreindRequests).Include(u => u.Messages).FirstOrDefault();
var messageCount = user.Messages.Where(m => m.HasBeenViewed == false).Count();
var friendRequests = user.FreindRequests.Where(f => f.HasBeenViewed == false).Count();
Clients.Caller.notificationCount(friendRequests + messageCount);
}
I'm not sure what the problem is. I'm guessing there is some interaction between the query and signalr hub where it is storing it in memory instead of getting the new information every time, but i'm not sure what to do to fix it.
Thanks for any help
Without using SQLDependency triggers, your best option is the manage the message state in the client, and just use the sql database for long term persistence, that way you can get the status of messages when the user logs in, and you have immediate access to state in the client.
I am trying to create an ASP.NET page that connects to QuickBooks Online Edition, read a couple of values, and display the results. So far I have downloaded the QuickBooks SDK but I have been unable to find a simple step-by-step example on how to create an asp.net page to connect to QuickBooks Online. The QuickBooks SDK documentation and the SDK itself is very confusing and overwhelming. Anyone know of a simple step by step tutorial on where to get started... or maybe a hint on the very first thing to do.
Yishai's answer is partially correct, but not entirely.
You can have your ASP .NET application log in and issue requests without having to send the user over to the QuickBooks Online log in page if you make sure to set the security preferences correctly when you connect up your application to QuickBooks Online Edition.
During the application registration process/connection process, it will ask you if you want to turn on or off login security with a prompt as below. You must tell it you want to turn off login security if you want to be able to access QuickBooks Online Edition data without forcing the user to log in every time. The prompt is something like:
"Do you want to turn on login security?"
You must select:
"No. Anyone who can log into [Application Name] can use the connection".
Outside of that, Yishai is correct about the process. To re-iterate, in a nutshell:
Register for a QBOE account
Register your integrated application with Intuit's AppReg service
Visit a specific link to tie your AppReg application to your QBOE account (make sure you turn off login security when it asks you!)
Make HTTPS POST requests to Intuit's servers to sign on using the connection ticket Intuit will provide you with
Make HTTPS POST requests to send qbXML requests to Intuit's servers, which you can use to add, modify, delete, and query records within QuickBooks Online Edition.
There is some additional documentation and some example requests on my QuickBooks development and integration wiki, specifically the QuickBooks Online Edition integration page.
I have built a solution that does what you're asking in PHP which adds, modifies, and queries data within QuickBooks Online Edition without requiring the user to log in everytime, and it works like a champ. It pushes and pulls order data between a PHP shopping cart (VirtueMart) and QuickBooks Online Edition. The PHP code is available here:
QuickBooks PHP Framework
As a side note, unless you're very familiar with generating SSL certificates and sending them via HTTPS POSTs, you'll save yourself a whole lot of trouble by using the DESKTOP model of communication, and not the HOSTED model. Just make sure to keep your connection ticket securely encrypted.
Also, Yishai's suggestion to: "One is to programatically hit up their login page and submit the credentials as if you were a user. I'm sure its not "supported" but it would likely work." goes specifically against the security/developer guidelines Intuit and the SDK set forth. If they catch you doing that, they'll ban your application from connecting to QuickBooks.
Here are all the steps I took to get this working. Special thanks to Keith Palmer for his comments, answers, and his website which really helped me get this working.
Register your application at http://appreg.quickbooks.com. This will give you your App ID and Application Name. I used these settings:
Target Application: QBOE
Environment: Production
Application Type: Desktop
(using Desktop made things much easier as far as not needing certificates)
A verification key is sent to your email address which you need to enter on page 2 of this wizard.
Set up your QBOE Connection. Once you finish registering your application in Step 1, you will then have an Application ID. Use this ID in the url below to set up your QBOE Connection:
https://login.quickbooks.com/j/qbn/sdkapp/confirm?serviceid=2004&appid=APP_ID
NOTE: Make sure to replace APP_ID in the above url with the Application ID that was created when you registered your application.
The wizard will take you through the following steps:
Specifying a name for your connection.
Granting Access Rights - I gave All Accounting rights since this was easiest.
Specify Login Security - I turned Login Security Off. This is important since it makes submitting the xml to the QBOE much easier since you do not need to get a session ticket for each user.
You will then be given a Connection Key.
At this point you now have the 3 important pieces of information in order to gain access to your QuickBooks Online Edition (QBOE) account.
Application Name
Application ID
Connection Key
Post the XML to QBOE with the 3 pieces of access information and the actual request into your QBOE database. Here is sample c# code that will post to the QBOE gateway. This will return all customers in your QuickBooks database. Make sure to update the xml below with your Application Name, Application ID, and Connection Key.
string requestUrl = null;
requestUrl = "https://apps.quickbooks.com/j/AppGateway";
HttpWebRequest WebRequestObject = null;
StreamReader sr = null;
HttpWebResponse WebResponseObject = null;
StreamWriter swr = null;
try
{
WebRequestObject = (HttpWebRequest)WebRequest.Create(requestUrl);
WebRequestObject.Method = "POST";
WebRequestObject.ContentType = "application/x-qbxml";
WebRequestObject.AllowAutoRedirect = false;
string post = #"<?xml version=""1.0"" encoding=""utf-8"" ?>
<?qbxml version=""6.0""?>
<QBXML>
<SignonMsgsRq>
<SignonDesktopRq>
<ClientDateTime>%%CLIENT_DATE_TIME%%</ClientDateTime>
<ApplicationLogin>APPLICATION_LOGIN</ApplicationLogin>
<ConnectionTicket>CONNECTION_TICKET</ConnectionTicket>
<Language>English</Language>
<AppID>APP_ID</AppID>
<AppVer>1</AppVer>
</SignonDesktopRq>
</SignonMsgsRq>
<QBXMLMsgsRq onError=""continueOnError"">
<CustomerQueryRq requestID=""2"" />
</QBXMLMsgsRq>
</QBXML>";
post = post.Replace("%%CLIENT_DATE_TIME%%", DateTime.Now.ToString("yyyy-MM-ddTHH:mm:ss"));
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.LoadXml(post);
post = xmlDoc.InnerXml;
WebRequestObject.ContentLength = post.Length;
swr = new StreamWriter(WebRequestObject.GetRequestStream());
swr.Write(post);
swr.Close();
WebResponseObject = (HttpWebResponse)WebRequestObject.GetResponse();
sr = new StreamReader(WebResponseObject.GetResponseStream());
string Results = sr.ReadToEnd();
}
finally
{
try
{
sr.Close();
}
catch
{
}
try
{
WebResponseObject.Close();
WebRequestObject.Abort();
}
catch
{
}
}
Couple things to note:
As pointed out by Keith Palmer the qbxml version needs to be 6.0 (even though the IDN Unified On-Screen Reference shows 7.0)
I needed to include the onError="continueOnError" attribute.
Setting the WebRequestObject.ContentLength property is required.
Content Type needs to be "application/x-qbxml"
And finally I received many "The remote server returned an error: (400) Bad Request." exceptions which were not helpful at all but in the end I was able to trace them to something wrong with the xml. So if you get this exception look to your xml as the source of the problem.
The outline of what you have to do are outlined in Chapter 7 of the QBSDK documentation (at least in the 7.0 version of the SDK that I have). You have to open a test account and get permission to connect to their servers.
Once you have your account setup, the basic authentication procedure consists of redirecting your user to the QuickBooks Online site to log in, and once the user has done that, QuickBooks calls back your application with an HTTPS post with a ticket, which is basically a session handle that you can use for your requests, so that the system knows you are authenticated. When you get that response, you parse it and send your own login request to the system based on what you got back.
Then (if I understood the documentation correctly) you are basically doing Https POSTS of xml files with the QuickBooks requests, and you get XML responses that you have to parse to get the data you want.
I hope that gets you started.
The rest of the SDK is documentation (which you will need to know how to form your requests and parse your responses) and everything else is concerned with how to communicate with the desktop product. The only thing you are going to need from the rest of the documentation is how to do error handling, which is really only important if you are posting data to QuickBooks. If you are just reading, it doesn't matter (either your request works out or it doesn't, you don't need to worry about if you need to retry or if that would result in duplicate data).
EDIT: Given your specific use case I see two options. (You aren't crazy, just not the typical QuickBooks Online scenario).
One is to programatically hit up their login page and submit the credentials as if you were a user. I'm sure its not "supported" but it would likely work.
The other is to cache the results (which you should probably do anyway) and have an admin screen where someone does log into QuickBooks online and update the results every morning or evening or whatever makes sense.
In most small businesses, they are going to opt for the first option, but the second one is going to work more consistently, robustly and actually be supported by Intuit if you have an issue.
This looks pretty close to what you need: www.QuickbooksConnector.com
Wasn't able to download it yet.