metakernel: Error method is noncompliant to Jupyter protocol

I posted this issue on the octave_kernel repo, but after digging into the source, I discovered it may be generic to all kernels based on Metakernel. So here’s the issue description again: So when a kernel errors out, you should be sending back an execute-reply like this:

{
    #...
    'content':{
        'status':'error',
        'ename':<your_error_name>,
        'evalue':<your_error_data>,
        'traceback':<your_traceback>
    }
    #...
}

That way Jupyter can process that as a proper error and not just assume it is any old STDOUT. Right now it would be a the easiest (?) fix to just rename what you are already returning to ‘traceback’ and insert some dummy values for the fields that you can’t get easily.

It would be really awesome if this were fixed because it’s breaking my use case!