I have created a sweet ASP.NET 4.0 UDP listener via WCF that starts on Application_Start. As usual, everything is hunky dory on my local machine. On my local machine using the VS Dev Environment and setting it to not open any page upon debug, the listener starts without browsing to anything yet. However, whenever I deploy to my shared host, I must access the site via a web browser before the listener will start. I do not have access to the IIS control panel but I do have some limited setting changes I can make to IIS via "Website Panel" software. I believe the shared host uses IIS 7.5.
Is there a better way to solve this rather than creating a polling service from my home PC to send an HTTP request to the shared host every so often to kick off the listener?
Requirements
The client sends UDP packets over a configurable port. I cannot change anything other than the IP and port that the client uses to connect
The solution must work with my shared host since I cannot afford a VPS at this time - otherwise I would've created a Windows Service. I got around creating a window service before by creating a polling service via WCF Application_Start but that only works because the info the users would see have to be on a webpage therefore application_start would always be called. In this case, the users/clients are not necessarily accessing the webpage.
Ideas:
Somehow pull this into a .svc. That way when the .svc is accessed by the client, it kicks off the listener for everyone else. But how can a .svc running on port 80 accept UDP calls? I'm also not sure if the client will be able to connect to more than an IP:PORT (I don't think it'd accept a .svc path like URL.com/awesomeListener.svc).
Any suggestions? Thank you so much.
If you are running ASP.NET 4.0 you can set it to auto-start for you which will fire Application_Start:
http://weblogs.asp.net/scottgu/archive/2009/09/15/auto-start-asp-net-applications-vs-2010-and-net-4-0-series.aspx
Related
I have a .Net service hosted on IIS. The service was accessible from IP:Port/Service.asmx, until recently when I couldn't access it from IP or System name again but only from Localhost:port/Service.asmx. I have pinged the server and it is replying. I have also confirmed that the local ip is listening on port 80. Really I don't know what is wrong, I have been on this for so long.
That's a hard one. Things I'd try:
Rebooting system.
Set a breakpoint at the earliest part of the request pipeline to verify whether the request is making it into your .Net code
Make a browser request via IP for a static file like an image. Is that served? That lets you see if the server will respond for a request that likely isn't going through Asp.Net.
So when I run my two services locally, I can hit service A which sends a command to service B which picks it up and processes it. Pretty straight forward. However, when I publish these to my web server and I send a request to service A which sends it to service B (I can see the message in service B's queue) but it won't get picked up and processed. I created an endpoint on service B that simply returns an OK response -- if I call this endpoint, effectively "touching" the service, everything kicks on and the messages get processed from that point on.
I figured maybe this had something to do with with late compiling, so I changed the publish to precompile on publish, but I get the same result.
Is there a way to have the service start processing as soon as it is published? Also worth noting that both services are WebAPI 2
Another option (probably more “standard”) would be to move the “handlers” into a Windows Service instead of a web application.
For this Windows Service you can leverage the NServiceBus Host which will turn a standard class library into a Windows Service for you. They have a good amount of documentation about this here: https://docs.particular.net/nservicebus/hosting/nservicebus-host/?version=Host_6
I would argue that this is more stable as you can separate the processing of sending commands (Web Application / WebApi) and processing commands / publishing events (NSB Host). The host can sit on the web server itself or you can put these on a different server.
Our default architecture is to have a separate server run our NSB Hosts as you scale web applications and NSB Hosts differently. If you run the NSB Host on the web server, you can get issues where a web app gets too much traffic and takes the NSB Host processing down. You can always start simple with using 1 server for both, monitor the server and then move things around as traffic increases.
Not sure if this is the "right way" to do things, but what I ended up doing is setting up each site to be always running and auto initialize.
App pool set to "Always Running"
Website set preload enabled = true
Web.config has webServer entry for application initialization doAppInitAfterRestart="true"
Web Role added to server "Application Initialization"
With those things being set, the deployment process is basically to publish the site and iisreset. If there are better options, I'm still looking :)
I'm developing a webservice that will, when called, notify another program via a tcp connection. My problem is where to store the open tcp connection. The way I understand web services, they start and end with each HTTP Request, with no room for application wide variables, like the open tcp connection.
Please correct me if I'm wrong.
Specifically, in what part of the asmx file, or outside of it, should I place the code for listening for incoming tcp traffic?
Application events in Global.asax should fire for a web service hosted as an application in IIS. You can use these. Keep in mind that they will fire even if a web page and not the web service is accessed in the same application.
You can place the tcp connection as a static member of the service class and make a static constructor that handles the instantiation.
This will create the tcp connection before the first access of the web service is handled and then persist the connection as long as the hosting process is running. The only drawback with that approach is that the tcp connection is process wide. If you host two instances of the web service within the same process (quite unlikely) they will share the same tcp connection.
Fortunately for you, you are wrong.
Application-wide events do fire plus you have the access to all asp.net containers, the Application container for application-level variables, the Session container for session-level variables (if the client side supports cookies, the session id could even be passed in a cookie) and the Items container for request-level variables.
However, whether or not this helps you to store an additional tcp listener (if I understand correcly) is another story, not obvious one.
So i want to to create a web application using asp.net to connect to another application (for example a simple windows form) using sockets. The problem is i'm behind firewall and i don't have the authority to mess with the firewall settings, what other options can i do besides sockets?
My application is fairly simple, the web application will be hosted on the internet and has a "connect" button, when its click it establish connection with the windows form that is on another computer and display the message "Connected" if its connected. All this will be tested behind some kind of corporal firewall. How do i get around this?
The firewall is there specifically to stop this kind of thing.
The bestway around it would be to have the Forms app poll the server for connectivity - this can be made to look near real time by making the server receive the request, then wait until it gets a connect action, or time out after a few minutes and return nothing. Then the forms app would request again.
I think instead of using directly a web application, you should look forward to create a web service to solve both the purposes. You can have its reference in both of them. your Web Form will make a request to connect to the web service instead of application. That will solve both purposes.
I have a situation very similar to the one in this question:
Selective Cache clearing across load balanced servers (ASP.Net)
The difference is that due to our hosting configuration, I am unable to address individual servers by IP address. Assuming I cannot access specific servers via web requests, is it possible to access the HttpContext of a web application running on the same machine? I'm thinking I could accomplish this with a windows service that I could address by machine name, or alternately a console application, I just don't know if I can gain access to the web application cache either way.
You can expose content of the WebCache of an app through some Remoting/WCF code built into the web app. I hope you can use localhost to access it from an app on the same box.