Update schema to conform to v4 json schema

IPython/nbformat/v4/v4.withref.json

@@ -1,46 +1,41 b''
 {
-    "$schema": "http://json-schema.org/draft-03/schema#",
+    "$schema": "http://json-schema.org/draft-04/schema#",
     "description": "IPython Notebook v4.0 JSON schema.",
     "type": "object",
     "additionalProperties": false,
+    "required": ["metadata", "nbformat_minor", "nbformat", "cells"],
     "properties": {
         "metadata": {
             "description": "Notebook root-level metadata.",
             "type": "object",
-            "required": true,
             "additionalProperties": true,
             "properties": {
                 "kernel_info": {
                     "description": "Kernel information.",
                     "type": "object",
-                    "required": false,
+                    "required": ["name", "language"],
                     "properties": {
                         "name": {
                             "description": "Name of the kernel specification.",
-                            "type": "string",
-                            "required": true
+                            "type": "string"
                         },
                         "language": {
                             "description": "The programming language which this kernel runs.",
-                            "type": "string",
-                            "required": true
+                            "type": "string"
                         },
                         "codemirror_mode": {
                             "description": "The codemirror mode to use for code in this language.",
-                            "type": "string",
-                            "required": false
+                            "type": "string"
                         }
                     }
                 },
                 "signature": {
                     "description": "Hash of the notebook.",
-                    "type": "string",
-                    "required": false
+                    "type": "string"
                 },
                 "orig_nbformat": {
                     "description": "Original notebook format (major number) before converting the notebook between versions.",
                     "type": "integer",
-                    "required": false,
                     "minimum": 1
                 }
             }
@@ -48,22 +43,20 b''
         "nbformat_minor": {
             "description": "Notebook format (minor number). Incremented for backward compatible 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,
             "maximum": 4
         },
         "cells": {
             "description": "Array of cells of the current notebook.",
             "type": "array",
-            "required": true,
             "items": {
-                "type": [
+                "type": "object",
+                "oneOf": [
                     {"$ref": "/definitions/raw_cell"},
                     {"$ref": "/definitions/markdown_cell"},
                     {"$ref": "/definitions/heading_cell"},
@@ -79,22 +72,20 b''
             "description": "Notebook raw nbconvert cell.",
             "type": "object",
             "additionalProperties": false,
+            "required": ["cell_type", "metadata"],
             "properties": {
                 "cell_type": {
                     "description": "String identifying the type of cell.",
-                    "enum": ["raw"],
-                    "required": true
+                    "enum": ["raw"]
                 },
                 "metadata": {
                     "description": "Cell-level metadata.",
                     "type": "object",
-                    "required": true,
                     "additionalProperties": true,
                     "properties": {
                         "format": {
                             "description": "Raw cell metadata format for nbconvert.",
-                            "type": "string",
-                            "required": false
+                            "type": "string"
                         },
                         "name": {"$ref": "/definitions/misc/metadata_name"},
                         "tags": {"$ref": "/definitions/misc/metadata_tags"}
@@ -108,16 +99,15 b''
             "description": "Notebook markdown cell.",
             "type": "object",
             "additionalProperties": false,
+            "required": ["cell_type", "metadata"],
             "properties": {
                 "cell_type": {
                     "description": "String identifying the type of cell.",
-                    "enum": ["markdown"],
-                    "required": true
+                    "enum": ["markdown"]
                 },
                 "metadata": {
                     "description": "Cell-level metadata.",
                     "type": "object",
-                    "required": true,
                     "properties": {
                         "name": {"$ref": "/definitions/misc/metadata_name"},
                         "tags": {"$ref": "/definitions/misc/metadata_tags"}
@@ -132,16 +122,15 b''
             "description": "Notebook heading cell.",
             "type": "object",
             "additionalProperties": false,
+            "required": ["cell_type", "metadata", "source", "level"],
             "properties": {
                 "cell_type": {
                     "description": "String identifying the type of cell.",
-                    "enum": ["heading"],
-                    "required": true
+                    "enum": ["heading"]
                 },
                 "metadata": {
                     "description": "Cell-level metadata.",
                     "type": "object",
-                    "required": true,
                     "properties": {
                         "name": {"$ref": "/definitions/misc/metadata_name"},
                         "tags": {"$ref": "/definitions/misc/metadata_tags"}
@@ -152,7 +141,6 b''
                 "level": {
                     "description": "Level of heading cells.",
                     "type": "integer",
-                    "required": true,
                     "minimum": 1,
                     "maximum": 6
                 }
@@ -163,27 +151,24 b''
             "description": "Notebook code cell.",
             "type": "object",
             "additionalProperties": false,
+            "required": ["cell_type", "metadata", "source", "outputs", "prompt_number"],
             "properties": {
                 "cell_type": {
                     "description": "String identifying the type of cell.",
-                    "enum": ["code"],
-                    "required": true
+                    "enum": ["code"]
                 },
                 "metadata": {
                     "description": "Cell-level metadata.",
                     "type": "object",
-                    "required": true,
                     "additionalProperties": true,
                     "properties": {
                         "collapsed": {
                             "description": "Whether the cell is collapsed/expanded.",
-                            "type": "boolean",
-                            "required": false
+                            "type": "boolean"
                         },
                         "autoscroll": {
                             "description": "Whether the cell's output is scrolled, unscrolled, or autoscrolled.",
-                            "enum": [true, false, "auto"],
-                            "required": false
+                            "enum": [true, false, "auto"]
                         },
                         "name": {"$ref": "/definitions/misc/metadata_name"},
                         "tags": {"$ref": "/definitions/misc/metadata_tags"}
@@ -193,9 +178,9 b''
                 "outputs": {
                     "description": "Execution, display, or stream outputs.",
                     "type": "array",
-                    "required": true,
                     "items": {
-                        "type": [
+                        "type": "object",
+                        "oneOf": [
                             {"$ref": "/definitions/execute_result"},
                             {"$ref": "/definitions/display_data_output"},
                             {"$ref": "/definitions/stream_output"},
@@ -206,7 +191,6 b''
                 "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
                 }
             }
@@ -216,11 +200,11 b''
             "description": "Result of executing a code cell.",
             "type": "object",
             "additionalProperties": false,
+            "required": ["output_type", "metadata", "prompt_number"],
             "properties": {
                 "output_type": {
                     "description": "Type of cell output.",
-                    "enum": ["execute_result"],
-                    "required": true
+                    "enum": ["execute_result"]
                 },
                 "metadata": {"$ref": "/definitions/misc/output_metadata"},
                 "prompt_number": {"$ref": "/definitions/misc/prompt_number"}
@@ -232,11 +216,11 b''
             "description": "Data displayed as a result of code cell execution.",
             "type": "object",
             "additionalProperties": false,
+            "required": ["output_type", "metadata"],
             "properties": {
                 "output_type": {
                     "description": "Type of cell output.",
-                    "enum": ["display_data"],
-                    "required": true
+                    "enum": ["display_data"]
                 },
                 "metadata": {"$ref": "/definitions/misc/output_metadata"}
             },
@@ -247,22 +231,20 b''
             "description": "Stream output from a code cell.",
             "type": "object",
             "additionalProperties": false,
+            "required": ["output_type", "metadata", "stream"],
             "properties": {
                 "output_type": {
                     "description": "Type of cell output.",
-                    "enum": ["stream"],
-                    "required": true
+                    "enum": ["stream"]
                 },
                 "metadata": {"$ref": "/definitions/misc/output_metadata"},
                 "stream": {
                     "description": "The stream type/destination.",
-                    "type": "string",
-                    "required": true
+                    "type": "string"
                 },
                 "text/plain": {
                     "description": "The stream's text output, represented as an array of strings.",
-                    "type": ["string", "array"],
-                    "required": false
+                    "type": ["string", "array"]
                 }
             }
         },
@@ -271,28 +253,25 b''
             "description": "Output of an error that occurred during code cell execution.",
             "type": "object",
             "additionalProperties": false,
+            "required": ["output_type", "metadata", "ename", "evalue", "traceback"],
             "properties": {
                 "output_type": {
                     "description": "Type of cell output.",
-                    "enum": ["error"],
-                    "required": true
+                    "enum": ["error"]
                 },
                 "metadata": {"$ref": "/definitions/misc/output_metadata"},
                 "ename": {
                     "description": "The name of the error.",
-                    "type": "string",
-                    "required": true
+                    "type": "string"
                 },
                 "evalue": {
                     "description": "The value, or message, of the error.",
-                    "type": "string",
-                    "required": true
+                    "type": "string"
                 },
                 "traceback": {
                     "description": "The error's traceback, represented as an array of strings.",
                     "type": "array",
-                    "items": {"type": "string"},
-                    "required": true
+                    "items": {"type": "string"}
                 }
             }
         },
@@ -301,13 +280,11 b''
             "metadata_name": {
                 "description": "The cell's name. If present, must be a non-empty string.",
                 "type": "string",
-                "required": false,
                 "pattern": "^.+$"
             },
             "metadata_tags": {
                 "description": "The cell's tags. Tags must be unique, and must not contain commas.",
                 "type": "array",
-                "required": false,
                 "uniqueItems": true,
                 "items": {
                     "type": "string",
@@ -316,26 +293,22 b''
             },
             "source": {
                 "description": "Contents of the cell, represented as an array of lines.",
-                "type": ["string", "array"],
-                "required": true
+                "type": ["string", "array"]
             },
             "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
             },
             "mimetype": {
                 "^[a-zA-Z0-9+-]+/[a-zA-Z0-9+-]+$": {
                     "description": "The cell's mimetype output (e.g. text/plain), represented as either an array of strings or a string.",
-                    "type": ["string", "array"],
-                    "required": false
+                    "type": ["string", "array"]
                 }
             },
             "output_metadata": {
                 "description": "Cell output metadata.",
                 "type": "object",
-                "required": true,
                 "additionalProperties": true
             }
         }