JSON Referencing and Schema

Persistent Computing on the Web with

JSON Schema and Referencing

Kris Zyp

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Overview

•JSON Referencing

•JSON Schema

•The possiblities...


JSON + Hyperlinks = JSON Referencing


http://www.sitepen.com/blog/2008/06/17/json-referencing-in-dojo/

JSON Referencing

•Cyclic

•Multiple references

•Cross-message references

•Cross-site references


JSON Referencing (ID Based)

{“name”:”Kris Zyp”,“id”:”kriszyp”,“children”:[{“id”:”jennikazyp”,“name”:”Jennika Zyp”}],“spouse”:{“name”:”Nicole Zyp”,“spouse”:{“$ref”:”kriszyp”},“children”:[{“$ref”:”jennikazyp”}]

}}


JSON Referencing (Path Based)

{“name”:”Kris Zyp”,“children”:[{“name”:”Jennika Zyp”}],“spouse”:{“name”:”Nicole Zyp”,“spouse”:{“$ref”:”#”},“children”:{“$ref”:”#.children”}

}}


JSON Referencing (ID + Path)

{“name”:”Kris Zyp”,“id”:”kriszyp”,“children”:[{“name”:”Jennika Zyp”}],“friends”:[{“$ref”:”jesse#.spouse”}]

}


JSON + Schema = JSON Schema


JSON Schema

schema:{"description":"A person", "type":"object", "properties": {"name": {"type":"string"}, "age" : {"type":"integer", "maximum":125}}}

instance:{“name”:”Kris”, “age”:30}


JSON Schema

Schema:{"description":"A person", "type":"object", "properties": {"name": {"type":"string"}, "age" : {"type":"integer", "maximum":125,

“optional”:true}, “friends”: {“type”:”array”,

“items”:{“type”:”object”}} }}

instance:{“name”:”Kris”, “friends”:[{“name”:”Nikki”}]}


JSON Schema

Schema:{“type”:”array”,“items”:[{“type”:”string”},{“type”:”number”}]

}

instance:[“foo”,44]


JSON Schema

Schema:{"description":"A person", "type":["object",”string”]}

instance:“foo”

instance:{“prop”:3}


JSON Schema

Schema:{"description":"A person", "type":["object",”string”]}

instance:“foo”

instance:{“prop”:3}


JSON Schema

schema:{"description":"A person", "type":"object", "properties": {"name": {"type":"string"}, "gender" : {"type":"string",

"enum”:[“male”,”female”]}}, “additionalProperties”:false}

instance:{“name”:”Kris”, “gender”:”male”}


What can we do with these?


JSON Schema + JSON Referencing

{"description":"A Social Person", “id”:”socialperson”, "type":"object", "properties": {"name": {"type":"string"}, "age" : {

"type":"integer", "maximum":125

}, "friends" : {

“type” : ”array”,“items” : {“$ref”:”socialperson”}

} }, “extends”:{“$ref”:”person”}}


http://blog.medryx.org/2008/07/24/jsonreststore-overview/

JSON Referencing + REST

•Lazy loading - Generic clients can auto-load objects as necessary

•Object identificationcan be used for saving state changes


JSON Referencing + REST

GET /Person/3

{ “name”:”Kris”, “friends”:[

{“$ref”:”4”},{“$ref”:”5”}

]}


JSON Referencing + JSON-RPC

POST /person/kriszyp

{“method”:”addFriend”,“id”:”1”,“params”:[{“$ref”:”jessesmith”}]

}


Applying data definitions to code


JSON Schema + Typed Code


JSON Schema Interfaces


JSON Schema Interface

{"description":"A person", "type":"object", "properties": {"name": {"type":"string"} }, “methods”:{ “getName”:{“returns”:{“type”:”string”}, “params”:[]}, “setName”:{“params”:[{“type”:”string”}]}, }}


Cross-site Referencing

{“name”:”Kris Zyp”,“id”:”kriszyp”,“friends”:[{“$ref”:”http://thezyps.com/person/nikki”},{“$ref”:”http://social.com/user/33”}

]}


Cross-site Typing


Mobile code (run anywhere)

•Code can run anywhere

-Server JavaScript Environment

-Browser JavaScript Environment

•Consistent persisted data structures across environments


Connecting and structuring data for the

futureJSON Schema and JSON

Referencing


JSON Referencing and Schema

Technology