SDK should Honor FunctionName attribute

[MikeStall]

We added a FunctionName attribute #1075
It's only a placeholder used by VS tooling, but SDK should honor this attribute too and plumb it through.

1. Function indexing
2. {sys.MethodName}
3. JobHost.Call? (maybe moot since that uses MethodInfo, but double check)
4. Dashboard
5. New InvokeFunctionFilterAttribute attribute that specifies function names

[paulbatum]

sys.MethodName should be the actual name of the method, it shouldn't be overridden by the functionname attribute

[MikeStall]

@paulbatum - I'd disagree. The actual C# method name should be viewed as an implementation detail - we don't want things taking a direct dependency on that. VS Tooling includes [FunctionName] attributes by default and that's what they show up in Script. For example, Bot uses {sys.MethodName} and expects to get the Script function name which would be [FunctionName].

[fabiocav]

I agree that {sys.MethodName} should reflect the method name as opposed to the logical function name. If we want to expose a way to get the function name, we should probably introduce a {sys.FunctionName} instead, as passing the function name when binding to the method would be surprising/confusing.

[MikeStall]

@fabiocav - please see my comments above. Exposing the reflection name would actually be incorrect; and there's not a good reason to add that low-level functionality.

[fabiocav]

I agree, but I'd argue that, given its name today, that's what people would expect. We don't refer to the function name as a method name anywhere. Introducing a FunctionName and perhaps deprecating MethodName would probably be the right approach.

[MikeStall]

This is recently new surface area. If it's a naming issue, we can do a full rename MethodName --> FunctionName, and we just need to update BOT. But we shouldn't have anything handing out the underlying Reflection name.

[paulbatum]

I'm fine with that, assuming we never disclosed sys.methodname publicly and therefore not a breaking change

[MikeStall]

It was added here: 962dfa6 on April 24th.