Should we model compilation errors as JSON-RPC errors?

@jvican how compile errors in a CompileResult should be communicated.

In the current implementation, a CompileResult contains no specific information as to compile errors, but by being a successful result it signals that the overall compilation succeded. In the case of any error, a JsonRpc error result is returned. Individual per-target CompileReport notifications communicate the results during compilation.

The argument for this mechanic is that a client can assume a successful result allows to resume normally with dependent tasks.

The argument against is that compile errors are a part of normal operation of the compiler, and only internal errors should trigger exception handling.

To be discussed for bsp 2.0

[olafurpg]

I recommend using JSON-RPC errors only for 1) error handling at the JSON-RPC layer and 2) internal server error. Application-level errors like “compilation failed” should be encoded in the protocol messages.

[jvican]

“error: code and message set in case an exception happens during the request.”

Yeah, which are JSON-RPC errors.

I also think that we should perhaps move valid errors like compilation failed to the BSP layer instead of JSON-RPC in BSP 2.0. That will be conceptually simpler.