[apps-discuss] JSON patch: "test" operation

[Julian Reschke <[e-mail]>]

Hi,

this came up during discussions of patch formats on the Apache 
jackrabbit-dev mailing list:

Would it make sense to add a "test" operation that allows checking the 
state of the JSON object to be modified?

It would be consistent with other diff formats that use context 
information in order to check whether the patch "cleanly applies".

An example would be:

    [
          { "test": "/vsn", "value" : 17 },
          { "replace": "/vsn", "value" : 18 },
          { "replace": "/balance", "value": 1234 }
    ]

And yes, concurrency control can also be achieved using conditional HTTP 
methods, but that doesn't mean that they don't make sense in the patch 
format as well.

Best regards, Julian