{
    "description": "custom json structure with references to generate notebook schema",
    "notebook":{
      "type": "object",
      "description": "notebook v3.0 root schema",
      "$schema": "http://json-schema.org/draft-03/schema",
      "id": "#notebook",
      "required": true,
      "additionalProperties": false,
      "properties":{
        "metadata": {
          "type": "object",
          "id": "metadata",
          "required": true,
          "description": "the metadata atribute can contain any additionnal information",
          "additionalProperties": true,
          "properties":{
            "name": {
              "id": "name",
              "description": "the title of the notebook",
              "type": "string",
              "id": "name",
              "required": true
            }
          }
        },
        "nbformat_minor": {
          "description": "Notebook format, minor number. Incremented for slight variation of notebook format.",
          "type": "integer",
          "minimum": 0,
          "id": "nbformat_minor",
          "required": true
        },
        "nbformat": {
          "description": "Notebook format, major number. Incremented between backward incompatible change is introduced.",
          "type": "integer",
          "minimum": 3,
          "id": "nbformat",
          "required": true
        },
        "worksheets": {
          "description": "Array of worksheet, not used by the current implementation of ipython yet",
          "type": "array",
          "id": "worksheets",
          "required": true,
          "items": {"$ref": "/worksheet"}
        }
      }
    },

    "worksheet": {
      "additionalProperties": false,
      "properties":{
        "cells": {
          "type": "array",
          "$schema": "http://json-schema.org/draft-03/schema",
          "description": "array of cells of the current worksheet",
          "id": "#cells",
          "required": true,
          "items": {"$ref": "/any_cell"}

        },
        "metadata": {
          "type": "object",
          "description": "metadata of the current worksheet",
          "id": "metadata",
          "required": true
        }
      }
    },

    "text_cell": {
      "type": "object",
      "description": "scheme for text cel and childrenm (level only optionnal argument for HEader cell)",
      "$schema": "http://json-schema.org/draft-03/schema",
      "id": "#cell",
      "required": true,
      "additionalProperties": false,
      "properties":{
        "cell_type": {
          "type": "string",
          "id": "cell_type",
          "required": true
        },
        "level": {
          "type": "integer",
          "minimum": 1,
          "maximum": 6,
          "id": "level",
          "required": false
        },
        "metadata": {
          "type": "object",
          "id": "metadata",
          "required": true
        },
        "source": {
          "description": "for code cell, the source code",
          "type": "array",
          "id": "source",
          "required": true,
          "items":
            {
              "type": "string",
              "description": "each item represent one line of the source code written, terminated by \n",
              "id": "0",
              "required": true
            }
        }
      }

    },

    "any_cell": {
        "description": "Meta cell type that match any cell type",
        "type": [{"$ref": "/text_cell"},{"$ref":"/code_cell"}],
        "$schema": "http://json-schema.org/draft-03/schema"
    },

    "code_cell":{
      "type": "object",
      "$schema": "http://json-schema.org/draft-03/schema",
      "description": "Cell used to execute code",
      "id": "#cell",
      "required": true,
      "additionalProperties": false,
      "properties":{
        "cell_type": {
          "type": "string",
          "id": "cell_type",
          "required": true
        },
        "metadata": {
          "type": "object",
          "id": "metadata",
          "required": true
        },
        "collapsed": {
          "type": "boolean",
          "required": true
        },
        "input": {
          "description": "user input for text cells",
          "type": "array",
          "id": "input",
          "required": true,
          "items":
            {
              "type": "string",
              "id": "input",
              "required": true
            }
        },
        "outputs": {
            "description": "output for code cell, to be definied",
            "required": true,
            "type": "array"
        },
        "prompt_number": {
            "type": ["integer","null"],
            "required": true,
            "minimum": 0
        },
        "language": {
            "type": "string",
            "required": true
        }
      }

    }
}