skip additionalProperties validation on notebooks from the future

adding new keys is considered backward-compatible change,
so these additional keys should be ignored.

IPython/nbformat/tests/test3plus.ipynb

@@ -0,0 +1,164 b''
+{
+ "metadata": {
+  "cell_tags": [
+   [
+    "<None>",
+    null
+   ]
+  ],
+  "name": ""
+ },
+ "nbformat": 3,
+ "nbformat_minor": 5,
+ "extra": 5,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "nbconvert latex test"
+     ]
+    },
+    {
+     "cell_type": "markdown",
+     "extra_key": ["list"],
+     "metadata": {},
+     "source": [
+      "**Lorem ipsum** dolor sit amet, consectetur adipiscing elit. Nunc luctus bibendum felis dictum sodales. Ut suscipit, orci ut interdum imperdiet, purus ligula mollis *justo*, non malesuada nisl augue eget lorem. Donec bibendum, erat sit amet porttitor aliquam, urna lorem ornare libero, in vehicula diam diam ut ante. Nam non urna rhoncus, accumsan elit sit amet, mollis tellus. Vestibulum nec tellus metus. Vestibulum tempor, ligula et vehicula rhoncus, sapien turpis faucibus lorem, id dapibus turpis mauris ac orci. Sed volutpat vestibulum venenatis."
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "another_attr": {},
+     "source": [
+      "Printed Using Python"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "key": "value",
+     "input": [
+      "print(\"hello\")"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "meta": 5,
+       "stream": "stdout",
+       "text": [
+        "hello\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Pyout"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "from IPython.display import HTML\n",
+      "HTML(\"\"\"\n",
+      "<script>\n",
+      "console.log(\"hello\");\n",
+      "</script>\n",
+      "<b>HTML</b>\n",
+      "\"\"\")"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "html": [
+        "\n",
+        "<script>\n",
+        "console.log(\"hello\");\n",
+        "</script>\n",
+        "<b>HTML</b>\n"
+       ],
+       "metadata": {},
+       "output_type": "pyout",
+       "key": "value",
+       "prompt_number": 3,
+       "text": [
+        "<IPython.core.display.HTML at 0x1112757d0>"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "%%javascript\n",
+      "console.log(\"hi\");"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "javascript": [
+        "console.log(\"hi\");"
+       ],
+       "metadata": {},
+       "output_type": "display_data",
+       "text": [
+        "<IPython.core.display.Javascript at 0x1112b4b50>"
+       ]
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 3,
+     "metadata": {},
+     "source": [
+      "Image"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "from IPython.display import Image\n",
+      "Image(\"http://ipython.org/_static/IPy_header.png\")"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "metadata": {},
+       "output_type": "pyout",
+       "more": "data",
+       "png": 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L0amUWggcqrXO8gg2FKHG2CdW4Uem9XvBlUflu7RUaiByU3lPa92ZKN8cSav8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\nHMRRca/E5hVINNIVwI2B56z6/3ExLRI31pXNAAAAAElFTkSuQmCC\n",
+       "prompt_number": 6,
+       "text": [
+        "<IPython.core.display.Image at 0x111275490>"
+       ]
+      }
+     ],
+     "prompt_number": 6
+    }
+   ],
+   "keys": ["value", "s"],
+   "metadata": {}
+  }
+ ]
+}
  No newline at end of file

IPython/nbformat/tests/test_validator.py

@@ -43,3 +43,12 b' class TestValidator(TestsBase):'
             validate(nb)
         self.assertEqual(isvalid(nb), False)
 
+    def test_future(self):
+        """Test than a notebook from the future with extra keys passes validation"""
+        with self.fopen(u'test3plus.ipynb', u'r') as f:
+            nb = read(f)
+        with self.assertRaises(ValidationError):
+            validate(nb, version=3)
+
+        self.assertEqual(isvalid(nb, version=3), False)
+        self.assertEqual(isvalid(nb), True)

IPython/nbformat/validator.py

@@ -4,6 +4,7 b''
 from __future__ import print_function
 import json
 import os
+import warnings
 
 try:
     from jsonschema import ValidationError
@@ -24,13 +25,34 b' from IPython.utils.importstring import import_item'
 
 validators = {}
 
-def get_validator(version=None):
+def _relax_additional_properties(obj):
+    """relax any `additionalProperties`"""
+    if isinstance(obj, dict):
+        for key, value in obj.items():
+            if key == 'additionalProperties':
+                print(obj)
+                value = True
+            else:
+                value = _relax_additional_properties(value)
+            obj[key] = value
+    elif isinstance(obj, list):
+        for i, value in enumerate(obj):
+            obj[i] = _relax_additional_properties(value)
+    return obj
+
+def get_validator(version=None, version_minor=None):
     """Load the JSON schema into a Validator"""
     if version is None:
         from .current import nbformat as version
 
-    if version not in validators:
-        v = import_item("IPython.nbformat.v%s" % version)
+    v = import_item("IPython.nbformat.v%s" % version)
+    current_minor = v.nbformat_minor
+    if version_minor is None:
+        version_minor = current_minor
+
+    version_tuple = (version, version_minor)
+
+    if version_tuple not in validators:
         try:
             v.nbformat_schema
         except AttributeError:
@@ -39,10 +61,15 b' def get_validator(version=None):'
         schema_path = os.path.join(os.path.dirname(v.__file__), v.nbformat_schema)
         with open(schema_path) as f:
             schema_json = json.load(f)
-        validators[version] = Validator(schema_json)
-    return validators[version]
 
-def isvalid(nbjson, ref=None, version=None):
+        if current_minor < version_minor:
+            # notebook from the future, relax all `additionalProperties: False` requirements
+            schema_json = _relax_additional_properties(schema_json)
+
+        validators[version_tuple] = Validator(schema_json)
+    return validators[version_tuple]
+
+def isvalid(nbjson, ref=None, version=None, version_minor=None):
     """Checks whether the given notebook JSON conforms to the current
     notebook format schema. Returns True if the JSON is valid, and
     False otherwise.
@@ -51,14 +78,14 b' def isvalid(nbjson, ref=None, version=None):'
     `validate` function instead.
     """
     try:
-        validate(nbjson, ref, version)
+        validate(nbjson, ref, version, version_minor)
     except ValidationError:
         return False
     else:
         return True
 
 
-def better_validation_error(error, version):
+def better_validation_error(error, version, version_minor):
     """Get better ValidationError on oneOf failures
 
     oneOf errors aren't informative.
@@ -79,10 +106,11 b' def better_validation_error(error, version):'
             try:
                 validate(error.instance,
                     ref,
-                    version=version
+                    version=version,
+                    version_minor=version_minor,
                 )
             except ValidationError as e:
-                return better_validation_error(e, version)
+                return better_validation_error(e, version, version_minor)
             except:
                 # if it fails for some reason,
                 # let the original error through
@@ -91,20 +119,21 b' def better_validation_error(error, version):'
     return error
 
 
-def validate(nbjson, ref=None, version=None):
+def validate(nbjson, ref=None, version=None, version_minor=None):
     """Checks whether the given notebook JSON conforms to the current
     notebook format schema.
 
     Raises ValidationError if not valid.
     """
     if version is None:
-        from .current import nbformat
-        version = nbjson.get('nbformat', nbformat)
+        from .reader import get_version
+        (version, version_minor) = get_version(nbjson)
 
-    validator = get_validator(version)
+    validator = get_validator(version, version_minor)
 
     if validator is None:
         # no validator
+        warnings.warn("No schema for validating v%s notebooks" % version, UserWarning)
         return
 
     try:
@@ -113,5 +142,5 b' def validate(nbjson, ref=None, version=None):'
         else:
             return validator.validate(nbjson)
     except ValidationError as e:
-        raise better_validation_error(e, version)
+        raise better_validation_error(e, version, version_minor)