[mythtv] V2 Service API Problem with more than 9 parameters - Qt restriction

[Peter Bennett]

Regarding the conversion of service APIs to the new web server framework.

I am getting this from the converted Video Service:

2021-07-06 09:28:41.737791 W  MetaMethod: Method 'UpdateVideoMetadata' 
takes more than 9 parameters; will probably fail

On looking at the code I find that it is issuing this message from 
libs/libmythbase/http/mythhttpmetamethod.cpp:56

Apparently it uses QMetaMethod, which allows only up to 9 parameters. 
Many of our service methods use more than that, for example the method 
mentioned in the warning takes 38 parameters.

I did test UpdateVideoMetadata with only three of the optional 
parameters and it worked, but I assume if I use more than 9 or past the 
ninth, it will not work. I have not tested to see what actually happens.

Before I start testing and digging into the code to see what can be 
changed to accommodate this, does anybody have any knowledge of what the 
plan was here? When the new framework was designed was this just ignored 
or is there a planned method of dealing with it?

Peter