{
    "$schema": "http://json-schema.org/draft-03/schema#",
    "description": "IPython Notebook v4.0 JSON schema.",
    "type": "object",
    "additionalProperties": false,
    "properties": {
        "metadata": {
            "description": "Notebook root-level metadata.",
            "type": "object",
            "required": true,
            "additionalProperties": true,
            "properties": {
                "language": {
                    "description": "Language of the notebook's kernel.",
                    "type": "string",
                    "required": true
                },
                "kernel_info": {
                    "description": "Other kernel information, to be determined."
                    "type": "object",
                    "required": true,
                    "additionalProperties": true
                }
            }
        },
        "nbformat_minor": {
            "description": "Notebook format (minor number). Incremented for slight changes to the notebook format.",
            "type": "integer",
            "required": true,
            "minimum": 0
        },
        "nbformat": {
            "description": "Notebook format (major number). Incremented between backwards incompatible changes to the notebook format.",
            "type": "integer",
            "required": true,
            "minimum": 4
        },
        "orig_nbformat": {
            "description": "Original notebook format (major number) before converting the notebook between versions.",
            "type": "integer",
            "required": false,
            "minimum": 1
        },
        "cells": {
            "description": "Array of cells of the current notebook.",
            "type": "array",
            "required": true,
            "items": {
                "type": [
                    {"$ref": "#/definitions/text_cell"},
                    {"$ref": "#/definitions/heading_cell"},
                    {"$ref": "#/definitions/code_cell"}
                ]
            }
        }
    },

    "definitions": {

        "text_cell": {
            "description": "Notebook text cell.",
            "type": "object",
            "additionalProperties": false,
            "properties": {
                "cell_type": {
                    "description": "String identifying the type of cell.",
                    "enum": ["markdown", "raw"],
                    "required": true
                },
                "metadata": {
                    "description": "Cell-level metadata.",
                    "type": "object",
                    "required": true,
                    "additionalProperties": true
                },
                "source": {
                    "description": "Contents of the cell, represented as an array of lines (each terminated by \n).",
                    "type": "array",
                    "required": true,
                    "items": {
                        "type": "string",
                        "pattern": "^.*\n$"
                    }
                }
            }
        },

        "heading_cell": {
            "description": "Notebook heading cell.",
            "type": "object",
            "additionalProperties": false,
            "properties": {
                "cell_type": {
                    "description": "String identifying the type of cell.",
                    "enum": ["heading"],
                    "required": true
                },
                "metadata": {
                    "description": "Cell-level metadata.",
                    "type": "object",
                    "required": true,
                    "additionalProperties": true
                },
                "source": {
                    "description": "Contents of the cell, represented as an array of lines (each terminated by \n).",
                    "type": "array",
                    "required": true,
                    "items": {
                        "type": "string",
                        "pattern": "^.*\n$"
                    }
                },
                "level": {
                    "description": "Level of heading cells.",
                    "type": "integer",
                    "required": true,
                    "minimum": 1,
                    "maximum": 6
                }
            }
        },

        "code_cell": {
            "description": "Notebook code cell.",
            "type": "object",
            "additionalProperties": false,
            "properties": {
                "cell_type": {
                    "description": "String identifying the type of cell.",
                    "enum": ["code"],
                    "required": true
                },
                "metadata": {
                    "description": "Cell-level metadata.",
                    "type": "object",
                    "required": true,
                    "additionalProperties": true
                },
                "source": {
                    "description": "Contents of the cell, represented as an array of lines (each terminated by \n).",
                    "type": "array",
                    "required": true,
                    "items": {
                        "type": "string",
                        "pattern": "^.*\n$"
                    }
                }
                "outputs": {
                    "description": "Outputs of cell, to be defined.",
                    "type": "array",
                    "required": true
                },
                "collapsed": {
                    "description": "Whether the cell is collapsed/expanded.",
                    "type": "boolean",
                    "required": true
                },
                "autoscroll": {
                    "description": "Whether the cell's output should autoscroll.",
                    "type": "boolean",
                    "required": true
                },
                "prompt_number": {
                    "description": "The code cell's prompt number. Will be null if the cell has not been run.",
                    "type": ["integer", "null"],
                    "required": true,
                    "minimum": 0
                }
            }
        }
    }
}