Plugin Debugging

To demonstrate plugin debugging we will first create a simple virtual device and then show how its Lua code can be debugged.

Creating a virtual device

A device is described in several XML files, each serving a specific purpose:

• Device file (usually D_<device_name>.xml), which includes fields like deviceType, friendlyName, and others,
• Implementation file (usually I_<device_name>.xml), which includes implementation, actionList, and other elements, and
• Service file (usually S_<device_name>.xml).
• Other files may be used to store Lua scripts or UI descriptions. See plugin creation tutorial for details.

To create a virtual device, follow these steps:

• Open a new editor tab in the IDE, add the following code and save it in a file named D_SimplyVirtual.xml (this is our device description).

<?xml version="1.0"?>
<root xmlns="urn:schemas-upnp-org:device-1-0">
  <specVersion>
    <major>1</major>
    <minor>0</minor>
  </specVersion>
  <device>
    <deviceType>urn:schemas-zerobrane-com:device:SimplyVirtual1</deviceType>
    <friendlyName>ZeroBrane Virtual Test</friendlyName>
    <manufacturer>ZeroBrane</manufacturer>
    <manufacturerURL>http://studio.zerobrane.com/vera</manufacturerURL>
    <implementationList>
      <implementationFile>I_SimplyVirtual.xml</implementationFile>
    </implementationList>
  </device>
</root>

• Open another tab, add the following code and save it in a file named I_SimplyVirtual.xml (this is our implementation description).

<?xml version="1.0"?>
<implementation>
  <functions>
  function simply_virtual_startup(lul_device)
    require('mobdebug').start('IDE-ip-address') -- address of computer running IDE
    luup.log("Simply virtual #" .. lul_device)
    require('mobdebug').done()
    return true
  end
  </functions>
  <startup>simply_virtual_startup</startup>
</implementation>

• Start a debugging session on a Lua script (not an .xml file!) and upload D_SimplyVirtual.xml and I_SimplyVirtual.xml files to the Vera device by using right click in the editor and select Upload to ... option from the context menu.
• Now go to your Vera device web interface at http://device-ip-address/cmh/ and select Apps, then Develop Apps, and Create device.
• Enter the name of the device file (D_SimplyVirtual.xml in our case) into Upnp Device Filename field.
• (optional) You may enter the name of the implementation file (I_SimplyVirtual.xml), but since we already added it as <implementationFile> to our device file, this is not needed.
• Enter Simply Virtual as the name of the device in the Description field.
• Select Create device.

In this example we used urn:schemas-zerobrane-com:device:SimplyVirtual1 as the device type, but you can reference one of the existing device types.

Debuging device startup Lua code

Note that we added require('mobdebug').start() and require('mobdebug').done() calls to the function we registered as startup function. This function will be called when the device is loaded and will make a debugging call to the IDE (by using the IP address of the IDE you specified in the start() call).

Now if you restart the luup engine from the Vera UI (by selecting the Reload button) or from the IDE (by selecting Restart Luup engine from the context menu in the editor) you will see a new tab opened in the IDE with the content of your “startup” function:

function simply_virtual_startup(lul_device)
  require('mobdebug').start('IDE-ip-address') -- address of computer running IDE
  luup.log("Simply virtual #" .. lul_device)
  require('mobdebug').done()
  return true -- http://wiki.micasaverde.com/index.php/Luup_Declarations#.3Cstartup.3E
end

You should now see the debugging suspended at the luup.log line. You can then step through the code (and will see the values printed to the output window), inspect variables, and use other debugging functions.