the title is quite general but my doubt is specific.
I have doubt regarding where to write the service logic code (in service control handler or in ServiceMain),as in whatever the functionality the service would perform . Is it in ServiceMain ?
I have looked upon these topics on MSDN relate to service. But ,didn't help me
http://msdn.microsoft.com/en-us/library/ms687414%28VS.85%29.aspx
http://msdn.microsoft.com/en-us/library/ms685984%28v=vs.85%29.aspx
Basically, I want to start a socket listening on windows using a service. This listening socket logic code will be in service file because of I am going to use winexe utility to send this service from linux box to windows box. currently, winexe sends the winexesvc service file on windows. So, ultimately I am going to replace the existing winexesvc service so that it will perform listening on a particular port function when sent on windows. (Service skeleton would remain same but its task performing logic will change,right?). please tell if I am missing anything.
Thanks in advance.
Service control handler should only, well, handle control messages that are sent to the service (the ones shown in the examples you linked are SERVICE_CONTROL_STOP and SERVICE_CONTROL_INTERROGATE). These control messages are sent to the service from the environment.
The logic of your service should be implemented in the ServiceMain function, when all required initialization is done. In the example at the URL in your post, the service logic code is put into the SvcInit function (which is probably not the most appropriate name for a function that implements logic of a service).
Related
I have created WCF service in .net.
It is called by Java client, how do I read parameters when service is being called?
Here is my code:
public string getMethod(string id, string name)
{
string str = name;
return str;
}
Here is my WPF application code, I have added web reference:
WebReference.Service1Soap client = new WebReference.Service1Soap();
string str = client.getMethod(id, name);
How do I read values of "id" and "name" called from Java client?
I am stuck here, please help me please!!
Any help would be greatly appreciated.
Thanks!!
The simplest way:
Run a local instance of the service in debug mode, or attach the visual studio debugger to WCF service host process.
Put a breakpoint in the getMethod() service operation code
Call the service with the java client.
Check the values using a watch or just mouseover.
EDIT.. from comments...
but I have set debug point, still it is not happening
That means that your java client call is not being made successfully. If your java client cannot call the service then you need to sort that out first. Please post a new question to address this, or there are plenty of stuff on google: https://www.google.co.uk/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=problem+calling+wcf+from+java
I need those parameter values in WPF application and I have to read
it. How to do it?
You can't send a message to a service and then have that data relayed to another client (WPF) unless you use callbacks via a duplex binding like wsDualHttpBinding, which is not a nice solution in my opinion. More reading here: http://www.codeproject.com/Articles/491844/A-Beginners-Guide-to-Duplex-WCF
If your java client needs to call into a WPF then you'll need to use ServiceHost inside your WPF application and host a WCF service from there. Look here for an example: http://blogs.msdn.com/b/brunoterkaly/archive/2013/11/01/wcf-service-hosting-how-to-host-a-wcf-service-from-inside-a-windows-presentation-foundation-application.aspx
EDIT 2
From Java, service client has been made successfully, and it is
getting the response. But how do I read parameters, and is there any
way or code, that "we come to know that .net service is being called".
Then the only thing you can do is either host the WCF service inside your WPF application, or use a duplex WCF binding on the service, and have the WPF application subscribe by registering a callback delegate. This way the service can call back to the client when something happens (a call is made).
Alternatively you could use a shared database which is updated with the call values when the java client makes the call. Your WPF app can then poll or use a SqlDependency to know when the data has changed.
I use NLog's WebService target in Silverlight and run into a problem if the logging service is unavailable.
What happens is that all calls to the logging service hang for a long time until they time out.
This is firstly ugly and secondly problematic in the face of a request limit, which I have under my given circumstances. After the request limit is reached due to several pending logging requests, the application also fails to make requests that are not logging related.
Ideally I'd like a WebService target that sends the requests sequentially, but I can't configure it to do that, can I?
Since I have full control about the logging server I could also move to a different target, but I'd rather have a purely configuration-based solution.
Some time back I implemented a logging target like that for Silverlight. We were using Common.Logging for .NET and it did not support Silverlight. So, we ported part of Common.Logging to Silverlight and implemented a "logging service adapter" to send our logging messages to a logging service. I implemented a logging queue using the producer/consumer pattern. Maybe you will find it useful.
In the end, the project that I was working on when I implemented this didn't go anywhere, so this particular piece of code is not in use.
Using WCF service via async interface from worker thread, how do I ensure that events are sent from the client "in order"
I'm not sure if I'm on the right lines but this is what I'm trying to do, I have a Silverlight application and a WCF service, the Silverlight app "subscribes" to the WCF service using PollingDuplex and the service can send data to any connected clients which works.
The service is marked with [ServiceContract(CallbackContract = typeof(IServiceCallback))] and it is single instanced
The problem is there is another service which should be able to call a standard method on this service to pass it data that will get distributed to the connected Silverlight clients, but because of the above settings it requires it to use callbacks (I can't change the other service).
Is there a way to have both types of operations, callback and standard in the same service if that makes sense?
Thanks for your time
Yes. It is possible. I guess CallbackContract parameter will not stop you from using your service as a regular request/response service (though I have not tried it).
But for the same contract, you may have to define two end points with different bindings, one with PollingDuplexHttpBinding and another one with basicHttpBinding (with silverlight this is the only other option).
You have to make sure that you are calling the right operation from the clients using duplex and basic http bindings.
I am reading a lot of conflicting information about how and when to close a WCF service.
Some people say you don't need to.
Some people say in the same place where you make the Async call
Some people say in the completed method.
Can someone point me to a place where microsoft actually says how to use this method? Also when do you call it?
Are you referring to client or service side closing
For client closing this is the recommended pattern - http://blogs.msdn.com/b/drnick/archive/2007/05/04/the-try-catch-abort-pattern.aspx
For services you can close the service host. For eg. in the self hosted service say using a windows NT Service, on Service shutdown you want to close the host so that clean up like un-registering ports etc. happen gracefully.
If you want to the try/catch/abort patten works for invocation and also for close. So you can provide a timeout and if you get a timeout exception, abort the instance.
I have a Linux/c client app that connects to a WCF web service over HTTP/SOAP (BasicHTTPBinding). I am using gSOAP. Can I implement the calls to the web-service using callback? I want to get the data asynchronously as call back.
Update: I have updated the question title.
WCF does support Duplex services, or those that have the ability to call back to the requesting client. Duplex services can be very complicated, as they are not only stateful, but they impose an contract implementation requirement on their clients.
Duplex services require the use of the WSDuplexHttpBinding. You will need to make use of the OperationContext to get a reference to the callback channel. Your clients MUST implement the callback contract in some class, and provide an InstanceContext that contains an instance of the callback class to the client proxy. Communications in both directions must be supported, and if the client is behind its own firewall or across the internet, this can be a complicated matter to resolve. Take care when writing duplex services...they are often more trouble than they are worth...so make sure you really need it. ;-)
The following page might be helpful:
http://msdn.microsoft.com/en-us/library/ms731064.aspx
The basicHttpBinding does not support callbacks. Another approach might be to have another method that the client can poll on for the response.
I am facing the same issue and the approach I am trying is to have a pair of gsoap servers/clients. Basically each process will listen on a port for soap calls and make its client calls to the other server. This way I avoid the polling or other complex approaches. The code has to be obviously thread safe for whatever business logic is implemented but the client/server combo pair is the simplest solution i have thought of so far.
Obviously one needs to be in control of both sides of the solutions the mentioned server and the mentioned client.