Cling UPnP not returning Actions

Question

I am using cling UPnP framework in android to connect to UPnP enabled device. I am successful in creating a device and browsing for available devices in the network. But for the samsung TV in the network the framework in not returning any actions. Here I am adding the service detail for the RenderingControl

<service>
<serviceType>urn:schemas-upnp-org:service:RenderingControl:1</serviceType>
<serviceId>urn:upnp-org:serviceId:RenderingControl</serviceId>
<controlURL>/upnp/control/RenderingControl1</controlURL>
<eventSubURL>/upnp/event/RenderingControl1</eventSubURL>
<SCPDURL>RenderingControl1.xml</SCPDURL>
</service>

This is the url for fetching the service descriptor xml file

> http://<ip address>:52235/dmr/SamsungMRDesc.xml

But the SCPDURL is relative and I am wondering whether the cling framework is searching for

http://<ip address>:52235/RenderingControl1.xml

instead of

http://<ip address>:52235/dmr/RenderingControl1.xml

Is it the reason for no actions being displayed for the services in cling UPnP or am I doing something really stupid?

How can I properly do this with cling UPnP?

Pavel Zdenek Pavel Zdenek · Accepted Answer · 2012-09-12T19:24:46

Just a clarification beforehand: the URL *SamsungMRDesc.xml is a device descriptor, not a service descriptor as you've written, right?

The <SCPDURL> per UPnP spec is "relative to the URL at which the device description is located". So yes, the correct absolute SCPDURL is the second one. But i would be highly surprised if there was really such severe bug in Cling. So to offer some theories:

What do you mean by "no actions being displayed in Cling UPnP" ? Is that some existing example app or your code? Cling itself does not provide any GUI. Might there be a bug in that code?
Are you absolutely sure about the device descriptor URL (SamsungMRDesc)? Is it reachable manually, i.e. by simply copy&pasting the URL into web browser?
What you see if you copy&paste the SCPDURL into web browser? Are there some <action> nodes under <actionList>?
Have you tried to query your Samsung TV with DeviceSpy from Intel Developer Tools ? You can see what an other UPnP stack sees, besides Cling. Furthermore, you can right-click on a Device node as well as Service node and see where DeviceSpy looks for the descriptions.
As a last instance, you can sniff what's being sent back and forth with Wireshark. Start with setting Wireshark IP filter to the address of your Samsung TV.

Theories 4 and 5 obviously require a PC connected to the same network as the TV (and your Android).

Cling UPnP not returning Actions

1 Answers