HTTP binding: input with no transformation

[Vlad (Vlad Ivanov)]

Is it possible to use HTTP binding with no transformation, like “default” in mqtt? Leaving transformation field blank results in a error, so does “default”. The closest thing I found was REGEX((.*)), but invoking regex processing just to return the same string seems like a waste of cpu time for me. Is there a “nop” transformation I could use with HTTP?

[rlkoshak (Rich Koshak)]

There was just recently some discussion about this for the TCP binding:

Opinion on TCP binding enhancement?

I agree as well. The more the same we can keep the syntax between the different binding configs (and Things for OH 2) the easier it is for users to learn and transfer their knowledge to other bindings.

I think that binding was updated to support “default”. It seems like the same update, for the same reasons should be made to HTTP binding as well.

@watou, does that make sense?

[watou (John Cocula)]

@Vlad

invoking regex processing just to return the same string seems like a waste of cpu time for me.

I agree. I think the syntax for <transformationrule> should be the same as in the MQTT binding (and as it will be in the TCP/UDP binding once this PR is further tested and merged).

It might also make sense to have the binding notice if REGEX((.*)) is given, and simply return the entire string, bypassing the actual RegEx code path.