More descriptive 'invalid json' message

[Vagabond]

When invalid json is provided, can we provide more information? The JSON provide and any parsing errors we get (if possible) would help diagnosing problems.

cc @jrwest

[engelsanchez]

@Vagabond @jrwest this is for the bucket type commands only, right? This would be very nice to have, but doesn't sound like an RC blocker. @jonmeredith ok to move to a later milestone?

[jonmeredith]

I'm concerned about the usability of the json-on-command-line stuff. Without seeing an example of the output it's hard to know.

[macintux]

$ ./riak-admin bucket-type create foo '{p:b}'
Cannot create bucket type foo: invalid json
$ ./riak-admin bucket-type create foo '{"p":"b"}'
Cannot create bucket type foo: no props field found in json

So we definitely alert on the primary problem if parsing works, but if invalid JSON is supplied, mochijson2 doesn't give us much help:

1> mochijson2:decode("{p:b}").
** exception error: no case clause matching <<"{p:b}">>
     in function  mochijson2:tokenize/2 (src/mochijson2.erl, line 529)
     in call from mochijson2:decode_object/3 (src/mochijson2.erl, line 330)
     in call from mochijson2:json_decode/2 (src/mochijson2.erl, line 307)

I don't think there's anything we can realistically do about this for RC. Removing the milestone, feel free to put it back.

[reiddraper]

Pushed to 2.1 milestone.