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Transfer data from Windows Service to Console Application repeatedly

Here is my scenario, I have a windows service that runs a task every 20 minutes, the task is: requesting updates from an API hosted by a remote website.
The response is a list of JSON objects, When the Service receives the list, it carries out a set of operations then appends more JSON objects, finally the service must push the list to a running console application.
My very specific question is: how to transfer this data from the windows service to the console App both directly and professionally
By directly I mean without intermediate solution like writing in a temp file or saving in SQL table ... etc.
By professionally I mean the best optimal solution especially without p/Invoke from the service to the console App.

You would definitely need a medium to communicate between these two processes. The communication can be done in a lot of ways on the same system.
With your explanation in Question it looks like one way communication. May be you can go for Inter-process communication via sockets(raw level) or Use a messaging framework for communication(WCF/SignalR) or you can even use a Message Queue system(MSMQ/RabbitMQ) etc.
You can get a specific answer if you can narrow down your question.

A nice, clean, 'modern' way of doing this, would be to host a Web API directly in the console application, and accept JSON input.
This is relatively easy to set up, and very easy to test and use.
Other methods include .NET remoting (which is not very modern any more), some other kind of service, like WCF, or any of the multitude of windows IPC methods.

I wrote an answer here that has some applicable code. Basically, the OP there wanted to send strings from a Windows Forms application to a console application and have the console application print the strings.
My recommendation is to use a Message Queue.
A few quick notes: first, you may have to enable the feature in Windows if you've never done so. Also, I guess under certain configurations of Windows you can't create the Message Queue directly from C#; if that's the case for you, you can create it manually (or there's probably a way to do it as part of an install script or something).
Here's the Windows Forms code:
private void button1_Click(object sender, EventArgs e)
{
// Or whatever name you end up calling it if you created the queue manually
const string myQueue = ".\\myQueue";
// It's possible that this won't work on certain computers
// If not, you'll have to create the queue manually
// You'll also need to turn the Message Queueing feature on in Windows
// See the following for instructions (for Windows 7 and 8): https://technet.microsoft.com/en-us/library/cc730960(v=ws.11).aspx
if (!MessageQueue.Exists(myQueue))
{
MessageQueue.Create(myQueue);
}
using (MessageQueue queue = new MessageQueue(myQueue))
{
queue.Formatter = new XmlMessageFormatter(new[] { typeof(string) });
queue.Send("Test");
}
}
Console application:
static void Main(string[] args)
{
// Or whatever name you use
const string myQueue = ".\\myQueue";
// See my comment on the corresponding line in the Windows Forms application
if (!MessageQueue.Exists(myQueue))
{
MessageQueue.Create(myQueue);
}
MessageQueue queue = new MessageQueue(myQueue);
queue.Formatter = new XmlMessageFormatter(new[] { typeof(string) });
while (true)
{
Message message = queue.Receive();
string messageText = message.Body.ToString();
// Close if we received a message to do so
if (messageText.Trim().ToLower() == "exit")
{
break;
}
else
{
Console.WriteLine(messageText);
}
}
}

Using Static Wrapper Class

In my search for a WebSockets library, I came across this website that provides Delphi and C# versions in download section. It grabbed my attention especially because the client-side of my application is developed using Delphi, and I'm trying to develop the server-side using C#.
Looking at the Chat sample for C#, I realized that it uses a wrapper class (sgcWebSocketLib) around the unmanaged DLL written in Delphi. Here is an excerpt from sgcWebSocketLib.cs:
public sealed class sgcWebSocketLib
{
private static volatile sgcWebSocketLib instance;
private static object syncRoot = new Object();
private sgcWebSocketLib()
{
}
public static sgcWebSocketLib Instance
{
get
{
if (instance == null)
{
lock (syncRoot)
{
if (instance == null)
instance = new sgcWebSocketLib();
}
}
return instance;
}
}
... //the rest is omitted
}
and the code from Start button in Chat server (a typical WinForms application):
private void btnStart_Click(object sender, EventArgs e)
{
string vOptions = "";
... //setting options according to UI values
sgcWebSocketLib.Instance.Server_LoadOptions(vOptions);
sgcWebSocketLib.Instance.Server_Start();
}
Now, here is the actual question: this Chat server uses a static property of sgcWebSocketLib class, and starts sending/receiving WebSocket stuff. Can I use the same approach in an ASP.Net application (WebForms or MVC)? Can I write the Chat server in ASP.Net using this wrapper class?
PS: I know there is SignalR and maybe others. But it has some limitations (IIS 8, Windows Server 2012 requirement for WebSocket) beside the unanswered communication problem with a Delphi VCL client.

Yes you can.
You will just have to pay attention to the Idle Time-out settings for your worker process (defaults to 20 minutes) as well as your Recycling settings (default is once every 29 hours). You may want to disable both settings if you want your application to never be recycled / go idle regardless of other parameters.
Recycling / idling will cause the worker process to shutdown, thus you'll lose any static variable and they'll have to be re instantiated when the process starts back up.
Check this answer for more info.

In IIS < 8 you won't be able of bind the WebSocket port to the same port than the web application (that is exactly what IIS8 can do)
Even with IIS8, the AppDomain is unable to recycle if there are WebSockets connected. So using the info that #Xeaz provided may be good idea. Usually I keep them in separate applications, since there is no point in mixing a connection oriented app (WebSockets), with a request-response one (regular HTTP). The only favorable point in doing that with IIS8 is the fact that both can share the port, but that is not really an issue aside of open/map an additional TCP port in the network, since cookies do not mind the port and WebSocket is not even affected by the SOP.
If the client is using the WebSocket protocol RFC6455 correctly, it should not matter which implementation is connecting to. I develop a websocket server for .NET/Mono 4.5 that works on Windows 7, take it a look if you go with the .NET server option.

How to invoke WCF method programmatically from windows service

I have successfully compiled and run Windows Service with WCF. With installutil, the Windows Service is successfully getting installed and started. I think I am at the end of my development and just need to invoke/call the method DoJobs() inside WCF. I don't need any user interaction and so I don't have any Windows forms or anything. I just want to invoke/call my WCF function programmatically just after serviceHost.Open();
The base address in app.config file is
http://localhost:8733/Design_Time_Addresses/WcfServiceLibrary1/Service1/
I am deploying my WCF from Windows service with the following code.
// Create a ServiceHost for the CalculatorService type and provide the base address.
serviceHost = new ServiceHost(typeof(WcfServiceLibrary1.Service1));
// Open the ServiceHostBase to create listeners and start listening for messages.
serviceHost.Open();
I have also added the service reference and created the below proxy, but not sure of its use.
WcfServiceLibrary1.WCFServiceRef.Service1Client
I have searched tutorials, the examples show how to invoke the WCF function on button_click event of any form after running Windows service. I just want to do that programmatically on start-up of Windows Service.
EDIT: The code inside my DoJobs() fetches the active tab url of firefox with DDE Client, which throws exception when done only in a Windows Service project but runs successfully when done in WCF project. Please see this for reference.
So I made a C#.Net solution with WCF called from a Windows Service and then I called DoJobs() inside Windows Service as shown below.
WcfServiceLibrary1.WCFServiceRef.Service1Client wcfObj = null;
...
protected override void OnStart(string[] args)
{
if (serviceHost != null)
{
serviceHost.Close();
}
serviceHost = new ServiceHost(typeof(WcfServiceLibrary1.Service1));
serviceHost.Open();
if (wcfObj == null)
{
wcfObj = new WcfServiceLibrary1.WCFServiceRef.Service1Client();
wcfObj.DoJobs();
}
}
But, it makes the call happen at the windows service layer, and is throwing the same DdeClient exceptions.
Can the base address url help any way to programmatically invoke DoJobs() in Web-Service? OR there are some other solutions.
Any help is highly appreciated.
Thanks.

This is my aggregated answer from my various comments I made to your post and to Noctis's answer (specifically that we did not know you were using DDE in the OP):
You can't use Dynamic Data Exchange (DDE) in a Windows Service because the latter does not have a message pump. Also DDE requires a Window handle to be passed as a parameter to DDE functions. You can use DDE in programs which do have a message pump does as a WinForms app. See this article for more information
Once your GUI app is running you can either minimize it to a Sys Tray icon or hide the app completely so the user is unaware. Regardless of its visible nature you should have no problem utilising DDE since it will have a message pump.
Now it may be the case you could add a message pump to a Windows Service but I wouldn't recommend it because it falls into the category of because you can do a thing, does not mean you should do a thing. A topic for another time. It's very similar to a recent SO question about how to display a WinForm in a console app - by default you can't and if you managed to you end up with an odd hybrid with much re-inventing of wheels. Not to mention its an ugly hack.
In summary, my best advice is to proceed with a GUI app.

Assuming you have :
// I'm assuming this is your proxy?
var proxy = WcfServiceLibrary1.WCFServiceRef.Service1Client;
// All you need to do is :
proxy.DoJobs() ;
Having seen your update and Micky`s answers, I'm just wondering why you're using DDE. Not sure what your requirements look like, but you can always use your MSMQ to send messages and queue things.

Reinstantiation issue using Inter App Communication with Windows Phone

I am developing an WP8 app that uses a webbrowser control that shows statefull server content. On WP8 you can switch between apps manually. E.g. if you want to copy&paste some information from one app into a browser input field. If you switch that way, the current app instance stays alive. That means the web session and the current page of the browser control will stay available.
Now I want another app to send some data directly into the app with the browser control - without restarting it...
From what I know, there are three ways to handle inter app communication:
register a file type that will open the app by launching that file from local storage
register an app protocol and use Launcher.LaunchUriAsync() to submit parameters in a query string
use a shared storage file
Detailed information can be found here.
I think the last approach is not usefull, because after you have started the second app, there is now way to activate the calling app or is there any usefull way to reactivate the webbrowser app?
I tried the second approach, but I am running in an issue, because it starts a new instance by design. That means InitializePhoneApplication is called. There is the entry point for the custom UriMapper that reads the incoming parameters. So the old app instance is killed and all session data, cookies and input fields are gone. With WP webbrowser control you are not able to store the cookie and page state, so a fast app resume is not possible also.
private void InitializePhoneApplication()
{
if (this.phoneApplicationInitialized)
{
return;
}
RootFrame = new TransitionFrame();
RootFrame.Navigated += this.CompleteInitializePhoneApplication;
RootFrame.UriMapper = new AssociationUriMapper();
//...
this.phoneApplicationInitialized = true;
}
Is there any other way or a possibility to use the shown approaches to send data between apps without restarting them using LanchUri()?
That means, to send some data back to a running instance without reinitializing the whole app, so that the page state and session state are still available on the target app.
Best regards
Holger

FastAppResume is the solution. I haven't used it and thought it also reinitiates the app. But it doesnt. This example shows how to reuse the existing instance.
Regards
Holger

Push Notifications with PushSharp - the basics

I need to push notifications to tens of thousands of iOS devices that my app installed. I'm trying to do it with PushSharp, but I'm missing some fundamental concepts here. At first I tried to actually run this in a Windows service, but couldn't get it work - getting null reference errors coming from _push.QueueNotification() call. Then I did exactly what the documented sample code did and it worked:
PushService _push = new PushService();
_push.Events.OnNotificationSendFailure += new ChannelEvents.NotificationSendFailureDelegate(Events_OnNotificationSendFailure);
_push.Events.OnNotificationSent += new ChannelEvents.NotificationSentDelegate(Events_OnNotificationSent);
var cert = File.ReadAllBytes(HttpContext.Current.Server.MapPath("..pathtokeyfile.p12"));
_push.StartApplePushService(new ApplePushChannelSettings(false, cert, "certpwd"));
AppleNotification notification = NotificationFactory.Apple()
.ForDeviceToken(deviceToken)
.WithAlert(message)
.WithSound("default")
.WithBadge(badge);
_push.QueueNotification(notification);
_push.StopAllServices(true);
Issue #1:
This works perfectly and I see the notification pop up on the iPhone. However, since it's called a Push Service, I assumed it would behave like a service - meaning, I instantiate it and call _push.StartApplePushService() within a Windows service perhaps. And I thought to actually queue up my notifications, I could do this on the front-end (admin app, let's say):
PushService push = new PushService();
AppleNotification notification = NotificationFactory.Apple()
.ForDeviceToken(deviceToken)
.WithAlert(message)
.WithSound("default")
.WithBadge(badge);
push.QueueNotification(notification);
Obviously (and like I already said), it didn't work - the last line kept throwing a null reference exception.
I'm having trouble finding any other kind of documentation that would show how to set this up in a service/client manner (and not just call everything at once). Is it possible or am I missing the point of how PushSharp should be utilized?
Issue #2:
Also, I can't seem to find a way to target many device tokens at once, without looping through them and queuing up notifications one at a time. Is that the only way or am I missing something here as well?
Thanks in advance.

#baramuse explained it all, if you wish to see a service "processor" you can browse through my solution on https://github.com/vmandic/DevUG-PushSharp where I've implemented the workflow you seek for, i.e. a win service, win processor or even a web api ad hoc processor using the same core processor.

From what I've read and how I'm using it, the 'Service' keyword may have mislead you...
It is a service in a way that you configure it once and start it.
From this point, it will wait for you to push new notifications inside its queue system and it will raise events as soon as something happens (delivery report, delivery error...). It is asynchronous and you can push (=queue) 10000 notifications and wait for the results to come back later using the event handlers.
But still it's a regular object instance you will have to create and access as a regular one. It doesn't expose any "outside listener" (http/tcp/ipc connection for example), you will have to build that.
In my project I created a small selfhosted webservice (relying on ServiceStack) that takes care about the configuration and instance lifetime while only exposing the SendNotification function.
And about the Issue #2, there indeed isn't any "batch queue" but as the queue function returns straight away (enqueue and push later) it's just a matter of a looping into your device tokens list...
public void QueueNotification(Notification notification)
{
if (this.cancelTokenSource.IsCancellationRequested)
{
Events.RaiseChannelException(new ObjectDisposedException("Service", "Service has already been signaled to stop"), this.Platform, notification);
return;
}
notification.EnqueuedTimestamp = DateTime.UtcNow;
queuedNotifications.Enqueue(notification);
}