Apologies in advance if this topic has been discussed somewhere, but I couldn’t find anything definitive in the forum archives. Or for that matter if the answer is self-evident.
I have a device that emits an xml message stream in response to receiving an HTTP get. The return xml schema varies by message content–there are approximately 4 different schemas that I can see, and messages are broadcast approximately every 3 seconds after the initial wget triggers the server response. Does openLuup have a way to set-up a callback similar to the UDP style callback? And secondly, I read the source code notes in xml.lua about the basic internal xml parser, but wasn’t sure what the boundaries were for its use, or the syntax for calling it.
The functionality I need is fairly straight forward. I need to start the message service via a wget which would activate the openLuup listener, parse the xml response (and reissue the wget if the connection drops), scan, and then act on the data. I know a listener can be done programmatically as many of the plugins do exactly that, but would much prefer a simpler call directly to openLuup to handle the listening. ;D
Any insights are greatly appreciated.
As a basic approach, I would choose the method that requires the least amount of overhead processing while maintaining a reliable connection as there is no need for any program modification of the call to the NVR. A parameter to set a “timeout” before a retry would be nice, though of course that can be handled in the listener call.