WCF Client configuration - base address? - wcf

I'm connecting a WCF client to a group of services all implementing the same contract and all at the same host. I was hoping that there would be a way to combine the endpoint definitions to cut down on configuration clutter. I also would rather not do it programmaticly - just by configuration. Right now, my config has this repeated many times:
<endpoint address="http://hostname/ServiceA.svc"
binding="wsHttpBinding" bindingConfiguration="WSHttpBinding_MyBinding"
contract="ServiceReference.ISearchService" name="ServiceA">
</endpoint>
<endpoint address="http://hostname/ServiceB.svc"
binding="wsHttpBinding" bindingConfiguration="WSHttpBinding_MyBinding"
contract="ServiceReference.ISearchService" name="ServiceB">
</endpoint>
// continued for ServiceC, ServiceD, etc
For server configurations, there is some notion of "baseAddressPrefixFilters" that can be used for this purpose - is there anything for client configuration?

There is the concept of a base address in WCF - unfortunately, that only works if you self-host, e.g. host your service in a console app or NT service. However, that only works on the server side - there's nothing similar on the client side. On the client side, you always have to define the complete, full service address your endpoint should connect to.
If you host in IIS, your service address is determined by the server name, the virtual directory (and possibly subdirectories under that) and the name of the *.svc file used to host the service in IIS. This is a fixed system convention and you cannot influence it, unfortunately (.NET 4 will bring some remedy to that).

Related

What to use as WCF net.tcp host baseAddress on different servers?

In my App.config, i have this base address specified ("jerrycan" is the name of my computer):
<service behaviorConfiguration="helloWorldServiceBehavior" name="OpdService.OpdService">
<endpoint address="/service" binding="netTcpBinding" bindingConfiguration="NewBinding0"
name="MainEndPoint" contract="OpdService.IOpdService">
<identity>
<dns value="jerrycan" />
</identity>
</endpoint>
<endpoint kind="udpDiscoveryEndpoint" />
<host>
<baseAddresses>
<add baseAddress="net.tcp://jerrycan:8000" />
<add baseAddress="http://jerrycan/service" />
</baseAddresses>
<timeouts openTimeout="00:00:15" />
</host>
</service>
Everything works fine until I run service on other computer — clients can find service through UDP discovery, but aren't able to connect, as service continues to send old address. When I change "jerrycan" to "localhost", only local clients are able to connect to service (but on any computer). Any clients on other computers try to connect to "localhost" with no success.
So what should I use as host address if I want to be able to run service on different computers without recompile? Should I store address somewhere in config file for every computer, or should I change address in runtime? I think, I'm missing something simple and fundamental here.
Or maybe I should use localhost (as in many wcf samples) and it's my client connection code who brings the problems:
EndpointAddress endpointAddress = findResponse.Endpoints[0].Address;
OpdChannelFactory = new DuplexChannelFactory<OpdServiceReference.IOpdService>(CallbackHandler,
new NetTcpBinding("MainEndPoint"), endpointAddress);
Again, when I use "localhost" as base address, "localhost" comes as endpoint address in findResponse.
Edit:
It seems like I found solution here: http://btw-blog.blogspot.com/2011/02/dynamic-base-address-for-wcf-service.html
The point is to replace host name in base address with * symbol (wildcard). It will be changed with actual host name in run time.
Haven't tested everything yet, but looks like it actually works.
It seems like I found solution here: http://btw-blog.blogspot.com/2011/02/dynamic-base-address-for-wcf-service.html
The point is to replace host name in base address with "*" symbol (wildcard). It will be changed with actual host name in run time.
Tested it and it worked great.
Right now your service endpoint address is:
net.tcp://jerrycan:8000/service
When you create clients on the computer which is hosting the service (jerrycan-pc) of course the local clients will be able to access the service by referencing
net.tcp://localhost:8000/service
and obviously other clients (on other computers on your network) can not connect to the service if they try to contact localhost, because the endpoint: net.tcp://localhost:8000/service, is calling the local computer which in this case is not hosting the service (only for jerrycan-pc). If jerrycan-pc is hosting the service, clients on jerrycan-pc can call the service by referencing localhost, but clients on say mike-pc must either try to call jerrycan-pc or jerrycan-pc's IP. If you change the endpoint in your service configuration to your service hosts IP or even computer name, and reference the service on other computers using the IP of the service host/computer name then they will be able to access it. For example if jerrycan-pc is hosting the service and it has an IP of 192.168.1.5, your clients can consume the service by referencing this endpoint:
net.tcp://192.168.1.5:8000/service
So in your service config change localhost to the IP address or PC name and try to contact that address on your clients instead of contacting localhost.

WCF Routing backup list in client

Is it possible to define a WCF backup list in a client, so that a single-point-of-contact routing service is not nessasary?
I have two services implementing the same contact (interface). If the first service is not avaliable I would like the client to know that the backup service is to be used.
Is this possible or do I have to create a routing service (single-point-of-contact) that the client would communication with?
<client>
<endpoint address="http://localhost:49192/OrdinaryCustomerService.svc"
binding="basicHttpBinding" bindingConfiguration="BasicHttpBinding_ICustomer"
contract="OrdinaryCustomerServiceReference.ICustomer" name="OrdinaryCustomerService" />
<endpoint address="http://localhost:49860/PremiumCustomerService.svc"
binding="basicHttpBinding" bindingConfiguration="BasicHttpBinding_ICustomer"
contract="PremiumCustomerServiceReference.ICustomer" name="PremiumCustomerService" />
</client>
<routing>
<backupLists>
<backupList name="CustomerBackupList">
<add endpointName="PremiumCustomerService"/>
</backupList>
</backupLists>
</routing>
Just an idea but i have a similar issue and i have been thinking about creating a routing service on the client (IIS webserver in my case) so that all request on the webserver can fail over to different web services. We also have multiple webservers for fail over so i would put a router on each.
Not ideal but best solution i have found so far. If the router on the IIS box goes down chances are the IIS will be down as well and therefore our system would have kicked over tot he other webserver anyway.
We also have proper wfc routers with backup for our middle teir but before it was a manual change to the webservice to handle this.

WCF - remote service without using IIS - base address?

I'm trying to get my head around the addressing of WCF services.
We have a client-server setup where the server occasionally (maybe once a day) needs to push data to each client. I want to have a lightweight WCF listener service on each client hosted in an NT service to receive that data. We already have such an NT service setup hosting some local WCF services for other tasks so the overhead of this is minimal.
Because of existing legacy code on the server I believe the service needs to be exposed as ASMX and use basicHttpBinding to allow it to connect.
Each client is registered on the server by the user (they need to configure them individually) so discovery is not the issue.
My question is, how does the addressing work? I imagine the user entering the client's address on the server in the form
http://0.0.0.0/MyService
or even
http://hostname/MyService
If so, how do I configure the client service in its App.config? Do I use localhost?
If not then what is the reccommended way of exposing the service to the server?
Note:
I don't want to host in IIS as that adds extra requirements to the hardware required for the client.
The clients will be almost certainly located on LANs, not over the public internet
You configure the base address of the service like so:
<system.serviceModel>
<services>
<service name="Ns.FooService">
<host>
<baseAddresses>
<add baseAddress="http://localhost:9999" />
</baseAddresses>
</host>
<endpoint
address="/foo"
binding="basicHttpBinding"
contract="Ns.IFooContract" />
</service>
</services>
</system.serviceModel>
And then your service could be accessible through http://servename:9999/foo. You may take a look at this article for more information.

WCF service running on localhost:4040

I hope this is a quick question. I have a WCF service running on IIS port 4040. I have added the following headers to this service
4040 (non load balanced domain)
4040 localhost
So locally I can reference this service as http://localhost:4040/service.svc and also by the fully qualified domain name. This is no problem for all the services on this machine, I can reference everything by localhost:4040
The issue comes when I try to access it from another server (as we have other apps that need to consume the service)
I get a 404 error, and was wondering whether the service is defaulting to being exposed on localhost loopback (127.0.0.1) therefore cannot be accessed.
The endpoint is defined as such:
<service behaviorConfiguration="ClaimChaseBehavior"
name="Modules.EClaims.ClaimChase">
<endpoint address=""
binding="basicHttpBinding"
contract="Domain.EClaims.DataInterfaces.IClaimChase" />
<endpoint address="mex" binding="mexHttpBinding"
contract="IMetadataExchange" />
</service>
Notice I don't define an address. The reason for this is to allow us to have a common config file (we are trying to get around defining machine domains/addresses and thus multiple configs)
Is there a way to make the WCF default to the machine IP instead of the loopback connector without defining the actual domain name
Hope this makes sense
Regards
Richard
When you're hosting your service in IIS, the address of the service is defined and controlled by the location of your *.svc file - you cannot override that by defining base addresses or explicit address on your service endpoints.
The service address will always be:
http://machinename/VirtualDirectory/YourService.svc
Marc
Check your web config. Have you spesified that the address of the service is localhost?
EDIT:
On second thoughts, it looks like a firewall problem, is port 4040 blocked by a local firewall?

dynamic refeences for WCF service

I have a WCF service hosted on IIS. I have a smartclient application which calls this WCF service through endpoints defined in app.config file.
Now when i publish this application using this configuration, IT throws an exception saying that no endpoint is listening at localhost.
How can i make it dynamic. By dynamic I mean IF i update the endpoint in app.config file the application should pick up that url instead of the url with which the application was published with.
I remember i could do it in webservices. Please help.
Your app.config would most likely contain something like:
<client>
<endpoint name="...."
address="........"
Check the address - that's the URL you're trying to connect to. You need to provide the server's address and port and path - no localhost, of course.
<client>
<endpoint name="...."
address="http://yourserver/yourVirtualDir/YourService.svc"
That should do the trick.
Marc