Synnefo » snf-ganeti

A note on JSON as used by RAPI

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JSON_ as used by Ganeti RAPI does not conform to the specification in

:rfc:`4627`. Section 2 defines a JSON text to be either an object

(``{"key": "value", …}``) or an array (``[1, 2, 3, …]``). In violation

of this RAPI uses plain strings (``"master-candidate"``, ``"1234"``) for

some requests or responses. Changing this now would likely break

existing clients and cause a lot of trouble.

.. highlight:: ruby

Unlike Python's `JSON encoder and decoder

<http://docs.python.org/library/json.html>`_, other programming

languages or libraries may only provide a strict implementation, not

allowing plain values. For those, responses can usually be wrapped in an

array whose first element is then used, e.g. the response ``"1234"``

becomes ``["1234"]``. This works equally well for more complex values.

Example in Ruby::

  require "json"

  # Insert code to get response here

  response = "\"1234\""

  decoded = JSON.parse("[#{response}]").first

Short of modifying the encoder to allow encoding to a less strict

format, requests will have to be formatted by hand. Newer RAPI requests

already use a dictionary as their input data and shouldn't cause any

problems.