We have developed the wcf service with the existing web service code. the existing customer wants to consume that service only changing the new url. They do not want to replace the proxy class. is it possible in any case.
The customer is able to consume the same with replacing the proxy and config. but he does not want to replace the proxy. please share ur comments whether it is possible or not.
You may be able to do this by configuring an endpoint using basicHttpBinding. I believe you will also need to force the use of the XML Serializer, and I don't know how to do that offhand, so someone else will have to help you with that. I'm concerned that there could still be small differences that would cause errors using the same proxy class.
On the other hand, if performance isn't the top consideration, you could create an ASMX service using the original class and method attributes from the old service. This ASMX service would then call the WCF service.
BTW, the ASMX service could call the WCF service on a fast endpoint. If they were running on the same server, they could use netNamedPipesBinding, for instance, but in any case could use netTcpBinding, which uses binary over TCP/IP. That would mitigate the performance difference from the extra hop.
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I am developing a wcf service (basicHttpBinding) that should also be consumed by non .net clients (e.g. Java clients). But now I wonder how the client can define his client config file. Or is this file only needed for .net-clients? (I am thinking of configurations like maxReceivedMessageSize or maxItemsInObjectGraph for example).
Each development platform (call it as you want: SOAP stack, Framework, API) has its own way to configure communication. You don't need to bother with it. You just need to expose correct WSDL and client's developer will be responsible for configuring the client application based on his needs.
If you want to extend documentation of your service in WSDL you can use wsdl:documentation. WCF doesn't offer it by default but you can use this technology sample to extend WCF. You can use such documentation for example to describe that service operation can return large amount of data. Another approach to add wsdl:documentation is using WCF Extras.
From the sound of it, the client shouldn't have access to those configuration options. For instance, why should a client to the WCF service be able to specify the maxReceivedMessageSize?
What you probably want to do is define these configuration options on the server-side. If a client makes a call and there is a conflict with one of your options (i.e. the client exceeds maxReceivedMessageSize), you'll want to throw a SoapException back to the client.
If you want to let the client have access to the configuration settings before he or she sends a request, you can always implement a simple web service method that sends back the values.
I have a WCF deployed on IIS. Now by adding web reference of it i am using it on my app.
So I have two questions:
Is it the best method of consuming WCF.
If the answer of first question is yes then what is the role of svcutil.exc, I mean what is the use of creating wcf proxy class. and if the answer is "No" then why?
It is the easiest solution if you develop with visual studio and have access the remote WCF service.
If you are developing using another IDE, you might want to use SvcUtil to generate your proxies.
If you prefer to have a simple CS file containing the generated client, you might also choose to generate it using SvcUtil.
You may also completely ignore SvcUtil and the Service Reference wizard and use the ChannelFactory class to generate proxies dynamically.
You should use "Add Service Reference" in Visual Studio (not Add Web Reference) for WCF.
It is the easiest way - since you can do it right in Visual Studio. What it does under the covers is basically call svcutil.exe (or you can do that manually, from the command line yourself), and create a service proxy class for use on the client side.
The use of svcutil.exe is many fold - you can create a client proxy class from a running service (or from an existing WSDL/XSD file), you can verify services, you can export metadata from a service for clients to consume, and a great many more options. It's the "Swiss Army Knife" of WCF tools.
WCF uses a concept that all calls to your service must go through a client proxy - this is the place where the entire WCF runtime lives, and where all the WCF extensibility points are located. This proxy converts your call to a method on the client into a serialized message that gets sent across the network to the server for processing, and it also handles "unpacking" the response from the call back into classes and objects on your client side for your use.
Adding a service reference is the quickest and easiest way but not always the best way. If you want performance then using ChannelFactory<T> is the way to go. You should know different ways to create a client side proxy and customisations that you can do.
An excellent resource is WcfGuidanceForWpf. Don't let the WPF in it scare you as it is really an excellent guidance for general WCF as well.
I have a WCF Service that I want my client to be able to consume from IIS without going through a proxy. The client was consuming asmx service in vbscript using the htc behavior:
<div id="oWSInterop" style="behavior:url(webservice.htc)"></div>
oWSInterop.useService "http://localhost/WSInteroperability.asmx", "WSInteroperability"
Set response = oWSInterop.WSInteroperability.callServiceSync("BuildSingleDoc", 1002, 19499, XMLEncode(sAdditionalDetail))
So basically I just want to make this work with making as few changes as possible on the existing client. Am I forced to use a proxy (that is, a class on the client side that exposes the operations in the WCF service) when consuming a WCF service? I do understand the benefits of a proxy and am not opposed to using it for most other client implementations, but in this case I'm not sure I have the time to deal with it on the client - i just want it to work the way it has been with only the endpoint changing.
A client-side proxy class to call the service?
Yes, you definitely need that (unless you do REST-based WCF services, which you can call with a HttpClient alone) - that's where the whole WCF runtime lives and does its magic.
If you want to call up REST-based services, you can do this without any proxy whatsoever - but then you're left to do XML or JSON parsing yourself. It can be done, but it might not be such a great idea.
What's the problem with the proxy?? It's really just a small wrapper that bundles up your calls into a serialized message and sends it to the server side. No big harm, in my opinion....
What are you seeing? What makes you thank that proxy is an issue? If that is server-side code, it should use the browsers settings (WinINet) which should work fine. Perhaps the "localhost" would be an issue, though, since to the client that still means "talk to yourself" (i.e. not the server).
If that is server side you'll probably need to configure WinHTTP appropriately; in particular, to skip the proxy for local addresses. Of course, "localhost" should loop-back anyway...
I have two related questions about Web services:
(1) I'm currently writing a set of applications, and it occurred to me that maybe I'm not using the right tool for the job. Here is the spec:
There are many Windows servers behind different VPNs and firewalls.
Each of the servers has a Windows service running, that reports various information about it to a centralized server, via a Web service, both of which I've written, and have access to.
So I'm both the producer and the consumer, and I'm staying on the same platform (.NET). Maybe a web service isn't the way to go? I'm using one purely because it's easy to write and deploy, and I'm the most comfortable with them. Should I really be using WCF for this?
(2) In the web service, I'm creating a State object to represent the state of the server, and sending it as a parameter. However, adding a service reference creates a proxy of the State class. It seems gacky to copy the properties of the State object to the proxy, and then send the proxy. Should I just replace the proxy class with the real class in the auto-generated code (i.e., include a reference to the State class instead)?
By "web services" I assume you mean an ASMX? I would go with WCF is possible, simply because you lose nothing but gain lots of flexibility. You could, for example, switch from XML-over-HTTP to Binary-over-TCP through a simple config change.
I would suggest to use WCF and use the Net.Tcp binding. It should be efficient enough for 300 clients. For the proxy class issue use the /reference option for the svcutil tool when you generate the proxy. This will allow you to share classes between server and client. I would not use this option if interoperability was a concern but since you stated that you develop both the clietn and the service and all in .Net it is a valid use in your case.
Your distinction between "Web Services" and WCF is a false distinction.
ASMX Web Services is the original .NET SOAP Web Service technology, introduced in .NET 1.0. It has been replaced by WCF, which can everything that ASMX can do, plus a whole lot more (including support for the WS-* standards).
Microsoft now considers ASMX Web Services, and the XML Serializer they're based on, to be "legacy technology". See "Microsoft says: ASMX Web Services are a “Legacy Technology”".
With WCF, since you have control of both sides of the operation, and can share the .dll in which the service contract is defined, you can and perhaps should be using ChannelFactory<IYourServiceContractHere> instead of auto-generating those ugly proxy classes with service references.
Here's the first hit I found on this topic: http://blogs.msdn.com/juveriak/archive/2008/02/03/using-channels-vs-proxies-in-wcf.aspx
If it is platform independent, I would certainly recommend WCF.
I've done exactly what your describing to great effect across more than 300 locations. I don't think you made the wrong call.
Another thing you could consider that would work well is using MSMQ. In this case, however, you'll either need to write event triggers (COM) or an event queue processing service.
I need to upgrade our web services to use WCF instead of ASMX. If the signatures of the web services stays the same, will existing clients that already call the ASMX service have to change anything on their end? Is there anyway to still use WCF but not force them to change anything?
Option 1 :
Using the current ASMX's WSDL, generate the client using svcutil.exe
Grab the generated interface and create a WCF service based on this interface
Output : One new WCF endpoint configured with basicHttpBinding. Clients need to update the URL at which they're sending the messages.
Option 2 :
Refactor your ASMX code. Move all the logic into a separate DLL.
Create a WCF service and use the logic in the refactored DLL.
Output : 2 endpoints, one for ASMX and another one for WCF
If you use the BasicHttpBinding for your new WCF service, and implement the same methods with the same message structure, existing callers should be able to call into this new WCF service without any change on their part.
There's also an AspNetCompatibilityRequirements attribute in order to get around some potential compatibility issue - see the MSDN documentation on it.
Marc