Re: [core] Designs to resolve streaming issues in SenML

[Michael Koster <[e-mail]>]

Hi Carsten,

Yes, of course! This approach reminds me of JSON streaming, where actual delimiters are inserted into a text stream, but this is much better because it uses the JSON array itself to encapsulate elements that can be individually parsed.

That makes the outer element an array and the inner elements either array type or map map type, and the map can be extended to embed element types representing the links, forms, and data within the base element dictionary.

It would be useful if the order of top level element types could be arbitrary e.g.: [ {},[],[],[],{},[],{},{} ... ]

So for example, to use this format I will extend the base element map as you indicated:

[ 
  { "bn": "urn:dev:mac:0024befffe804ff1/",
    "l": [
       {"href"...}...
    ]

  },
  [ { "n": "voltage", "t": 0, "u": "V", "v": 120.1 },
    { "n": "current", "t": 0, "u": "A", "v": 1.2 } 
  ]
]

If the order of top element types is optional, then the presence also could be, so I can adapt the new format by extending the base element to include links, forms, and items (getting rid of the “e” tag):

[ 
  { 
    "bn": “/light/brightness",
    "l": [
      { “href”: “change”,
        “rt”: [“change”,”form”],
        “ct”: “application/forms+senml+json”
      },
      { “href”: “tbr”,
        “rt”: [“property”, “item”, “param"],
        “ct”: “application/senml+json”
      },      
      { “href”: “tt”,
        “rt”: [“property”, “item”, “param"],
        “ct”: “application/senml+json”
      },
      { “href”: “actuations”,
        “rt”: “actuation”,
        “ct”: “application/collection+senml+json”
      }     
    ],
    “f”: [
      { “id”: “change”,
        "href”: “actuations”,
        “ct”: “application/collection+json”,
        “method”: “post”,
        “type”: “change”
        “template”: {
          “tbr”: “$targetbrightness”
          “tt”: “$transitiontime”
        }
      }
    ],
    “i”: [
      { “n”: “tbr”,
        “v”: “44.3”,
      },
      { “n”: “tt”,
        “v”: “1.0”,
      }
    ]	
  }
]

Having a top level array will allow me to accommodate collective operations on multiple object (bases) and allow the underlying implementation to chunk things at lease to the granularity of base objects mapped to top level elements.

So I’m OK with this if it allows me to use base elements as above.

Best regards,

Michael



> On Jan 16, 2016, at 8:09 AM, Carsten Bormann <[e-mail]> wrote:
> 
> Michael Koster wrote:
>> What is missing still from everything after -01 is the element tag that
>> I am re-using to indicate links and forms in the document:
> 
> What would be wrong with including this in the metadata part of -02:
> 
>   [{"bn": "urn:dev:mac:0024befffe804ff1/",
>     "l": [
>      {"href"...}...
>     ]},
>    [ { "n": "voltage", "t": 0, "u": "V", "v": 120.1 },
>      { "n": "current", "t": 0, "u": "A", "v": 1.2 } ]
>   ]
> 
> Grüße, Carsten