prompt: You will be provided with a partial code base and an issue statement explaining a problem to resolve.
  <issue>
  id and last_modified should be stripped before validating the JSON schema
  Otherwise it obliges everyone to add `id` and `last_modified` to their JSON schema or use `additionalProperties : true`.
  - http://spacetelescope.github.io/understanding-json-schema/reference/object.html#properties
  - See #256  
  - See #548 
  
  ``` diff
           try:
  -            jsonschema.validate(new, schema)
  +            stripped = copy.deepcopy(new)
  +            stripped.pop(self.model.id_field, None)
  +            stripped.pop(self.model.modified_field, None)
  +            jsonschema.validate(stripped, schema)
  ```
  
  id and last_modified should be stripped before validating the JSON schema
  Otherwise it obliges everyone to add `id` and `last_modified` to their JSON schema or use `additionalProperties : true`.
  - http://spacetelescope.github.io/understanding-json-schema/reference/object.html#properties
  - See #256  
  - See #548 
  
  ``` diff
           try:
  -            jsonschema.validate(new, schema)
  +            stripped = copy.deepcopy(new)
  +            stripped.pop(self.model.id_field, None)
  +            stripped.pop(self.model.modified_field, None)
  +            jsonschema.validate(stripped, schema)
  ```
  
  
  </issue>
  <code>
  [start of kinto/views/records.py]
  1 import jsonschema
  2 from cliquet import resource
  3 from cliquet.errors import raise_invalid
  4 from jsonschema import exceptions as jsonschema_exceptions
  5 from pyramid.security import Authenticated
  6 from pyramid.settings import asbool
  7 
  8 from kinto.views import object_exists_or_404
  9 
  10 
  11 class RecordSchema(resource.ResourceSchema):
  12     class Options:
  13         preserve_unknown = True
  14 
  15 
  16 _parent_path = '/buckets/{{bucket_id}}/collections/{{collection_id}}'
  17 
  18 
  19 @resource.register(name='record',
  20                    collection_path=_parent_path + '/records',
  21                    record_path=_parent_path + '/records/{{id}}')
  22 class Record(resource.ShareableResource):
  23 
  24     mapping = RecordSchema()
  25     schema_field = 'schema'
  26 
  27     def __init__(self, *args, **kwargs):
  28         super(Record, self).__init__(*args, **kwargs)
  29 
  30         # Check if already fetched before (in batch).
  31         collections = self.request.bound_data.setdefault('collections', {})
  32         collection_uri = self.get_parent_id(self.request)
  33         if collection_uri not in collections:
  34             # Unknown yet, fetch from storage.
  35             collection_parent_id = '/buckets/%s' % self.bucket_id
  36             collection = object_exists_or_404(self.request,
  37                                               collection_id='collection',
  38                                               parent_id=collection_parent_id,
  39                                               object_id=self.collection_id)
  40             collections[collection_uri] = collection
  41 
  42         self._collection = collections[collection_uri]
  43 
  44     def get_parent_id(self, request):
  45         self.bucket_id = request.matchdict['bucket_id']
  46         self.collection_id = request.matchdict['collection_id']
  47         return '/buckets/%s/collections/%s' % (self.bucket_id,
  48                                                self.collection_id)
  49 
  50     def is_known_field(self, field_name):
  51         """Without schema, any field is considered as known."""
  52         return True
  53 
  54     def process_record(self, new, old=None):
  55         """Validate records against collection schema, if any."""
  56         new = super(Record, self).process_record(new, old)
  57 
  58         schema = self._collection.get('schema')
  59         settings = self.request.registry.settings
  60         schema_validation = 'experimental_collection_schema_validation'
  61         if not schema or not asbool(settings.get(schema_validation)):
  62             return new
  63 
  64         collection_timestamp = self._collection[self.model.modified_field]
  65 
  66         try:
  67             jsonschema.validate(new, schema)
  68             new[self.schema_field] = collection_timestamp
  69         except jsonschema_exceptions.ValidationError as e:
  70             field = e.path.pop() if e.path else e.validator_value.pop()
  71             raise_invalid(self.request, name=field, description=e.message)
  72 
  73         return new
  74 
  75     def collection_get(self):
  76         result = super(Record, self).collection_get()
  77         self._handle_cache_expires(self.request.response)
  78         return result
  79 
  80     def get(self):
  81         result = super(Record, self).get()
  82         self._handle_cache_expires(self.request.response)
  83         return result
  84 
  85     def _handle_cache_expires(self, response):
  86         """If the parent collection defines a ``cache_expires`` attribute,
  87         then cache-control response headers are sent.
  88 
  89         .. note::
  90 
  91             Those headers are also sent if the
  92             ``kinto.record_cache_expires_seconds`` setting is defined.
  93         """
  94         is_anonymous = Authenticated not in self.request.effective_principals
  95         if not is_anonymous:
  96             return
  97 
  98         cache_expires = self._collection.get('cache_expires')
  99         if cache_expires is None:
  100             by_bucket = 'kinto.%s_record_cache_expires_seconds' % (
  101                 self.bucket_id)
  102             by_collection = '%s_%s_record_cache_expires_seconds' % (
  103                 self.bucket_id, self.collection_id)
  104             settings = self.request.registry.settings
  105             cache_expires = settings.get(by_collection,
  106                                          settings.get(by_bucket))
  107 
  108         if cache_expires is not None:
  109             response.cache_expires(seconds=cache_expires)
  110
  [end of kinto/views/records.py]
  </code>
  
  I need you to solve this issue by generating a single patch file that I can apply directly to this repository using git apply. Please respond with a single patch file in the following format.
  <patch>
  diff --git a/file.py b/file.py
  --- a/file.py
  +++ b/file.py
  @@ -1,27 +1,35 @@
   def euclidean(a, b):
  -    while b:
  -        a, b = b, a % b
  -    return a
  +    if b == 0:
  +        return a
  +    return euclidean(b, a % b)
   
   
   def bresenham(x0, y0, x1, y1):
       points = []
       dx = abs(x1 - x0)
       dy = abs(y1 - y0)
  -    sx = 1 if x0 < x1 else -1
  -    sy = 1 if y0 < y1 else -1
  -    err = dx - dy
  +    x, y = x0, y0
  +    sx = -1 if x0 > x1 else 1
  +    sy = -1 if y0 > y1 else 1
   
  -    while True:
  -        points.append((x0, y0))
  -        if x0 == x1 and y0 == y1:
  -            break
  -        e2 = 2 * err
  -        if e2 > -dy:
  -            err -= dy
  -            x0 += sx
  -        if e2 < dx:
  -            err += dx
  -            y0 += sy
  +    if dx > dy:
  +        err = dx / 2.0
  +        while x != x1:
  +            points.append((x, y))
  +            err -= dy
  +            if err < 0:
  +                y += sy
  +                err += dx
  +            x += sx
  +    else:
  +        err = dy / 2.0
  +        while y != y1:
  +            points.append((x, y))
  +            err -= dx
  +            if err < 0:
  +                x += sx
  +                err += dy
  +            y += sy
  +
  +    points.append((x, y))
       return points
  
  </patch>
golden_diff: diff --git a/kinto/views/records.py b/kinto/views/records.py
  --- a/kinto/views/records.py
  +++ b/kinto/views/records.py
  @@ -1,3 +1,5 @@
  +import copy
  +
   import jsonschema
   from cliquet import resource
   from cliquet.errors import raise_invalid
  @@ -64,12 +66,17 @@
           collection_timestamp = self._collection[self.model.modified_field]
   
           try:
  -            jsonschema.validate(new, schema)
  -            new[self.schema_field] = collection_timestamp
  +            stripped = copy.deepcopy(new)
  +            stripped.pop(self.model.id_field, None)
  +            stripped.pop(self.model.modified_field, None)
  +            stripped.pop(self.model.permissions_field, None)
  +            stripped.pop(self.schema_field, None)
  +            jsonschema.validate(stripped, schema)
           except jsonschema_exceptions.ValidationError as e:
               field = e.path.pop() if e.path else e.validator_value.pop()
               raise_invalid(self.request, name=field, description=e.message)
   
  +        new[self.schema_field] = collection_timestamp
           return new
   
       def collection_get(self):
  
verification_info: {"golden_diff": "diff --git a/kinto/views/records.py b/kinto/views/records.py\n--- a/kinto/views/records.py\n+++ b/kinto/views/records.py\n@@ -1,3 +1,5 @@\n+import copy\n+\n import jsonschema\n from cliquet import resource\n from cliquet.errors import raise_invalid\n@@ -64,12 +66,17 @@\n         collection_timestamp = self._collection[self.model.modified_field]\n \n         try:\n-            jsonschema.validate(new, schema)\n-            new[self.schema_field] = collection_timestamp\n+            stripped = copy.deepcopy(new)\n+            stripped.pop(self.model.id_field, None)\n+            stripped.pop(self.model.modified_field, None)\n+            stripped.pop(self.model.permissions_field, None)\n+            stripped.pop(self.schema_field, None)\n+            jsonschema.validate(stripped, schema)\n         except jsonschema_exceptions.ValidationError as e:\n             field = e.path.pop() if e.path else e.validator_value.pop()\n             raise_invalid(self.request, name=field, description=e.message)\n \n+        new[self.schema_field] = collection_timestamp\n         return new\n \n     def collection_get(self):\n", "issue": "id and last_modified should be stripped before validating the JSON schema\nOtherwise it obliges everyone to add `id` and `last_modified` to their JSON schema or use `additionalProperties : true`.\n- http://spacetelescope.github.io/understanding-json-schema/reference/object.html#properties\n- See #256  \n- See #548 \n\n``` diff\n         try:\n-            jsonschema.validate(new, schema)\n+            stripped = copy.deepcopy(new)\n+            stripped.pop(self.model.id_field, None)\n+            stripped.pop(self.model.modified_field, None)\n+            jsonschema.validate(stripped, schema)\n```\n\nid and last_modified should be stripped before validating the JSON schema\nOtherwise it obliges everyone to add `id` and `last_modified` to their JSON schema or use `additionalProperties : true`.\n- http://spacetelescope.github.io/understanding-json-schema/reference/object.html#properties\n- See #256  \n- See #548 \n\n``` diff\n         try:\n-            jsonschema.validate(new, schema)\n+            stripped = copy.deepcopy(new)\n+            stripped.pop(self.model.id_field, None)\n+            stripped.pop(self.model.modified_field, None)\n+            jsonschema.validate(stripped, schema)\n```\n\n", "before_files": [{"content": "import jsonschema\nfrom cliquet import resource\nfrom cliquet.errors import raise_invalid\nfrom jsonschema import exceptions as jsonschema_exceptions\nfrom pyramid.security import Authenticated\nfrom pyramid.settings import asbool\n\nfrom kinto.views import object_exists_or_404\n\n\nclass RecordSchema(resource.ResourceSchema):\n    class Options:\n        preserve_unknown = True\n\n\n_parent_path = '/buckets/{{bucket_id}}/collections/{{collection_id}}'\n\n\n@resource.register(name='record',\n                   collection_path=_parent_path + '/records',\n                   record_path=_parent_path + '/records/{{id}}')\nclass Record(resource.ShareableResource):\n\n    mapping = RecordSchema()\n    schema_field = 'schema'\n\n    def __init__(self, *args, **kwargs):\n        super(Record, self).__init__(*args, **kwargs)\n\n        # Check if already fetched before (in batch).\n        collections = self.request.bound_data.setdefault('collections', {})\n        collection_uri = self.get_parent_id(self.request)\n        if collection_uri not in collections:\n            # Unknown yet, fetch from storage.\n            collection_parent_id = '/buckets/%s' % self.bucket_id\n            collection = object_exists_or_404(self.request,\n                                              collection_id='collection',\n                                              parent_id=collection_parent_id,\n                                              object_id=self.collection_id)\n            collections[collection_uri] = collection\n\n        self._collection = collections[collection_uri]\n\n    def get_parent_id(self, request):\n        self.bucket_id = request.matchdict['bucket_id']\n        self.collection_id = request.matchdict['collection_id']\n        return '/buckets/%s/collections/%s' % (self.bucket_id,\n                                               self.collection_id)\n\n    def is_known_field(self, field_name):\n        \"\"\"Without schema, any field is considered as known.\"\"\"\n        return True\n\n    def process_record(self, new, old=None):\n        \"\"\"Validate records against collection schema, if any.\"\"\"\n        new = super(Record, self).process_record(new, old)\n\n        schema = self._collection.get('schema')\n        settings = self.request.registry.settings\n        schema_validation = 'experimental_collection_schema_validation'\n        if not schema or not asbool(settings.get(schema_validation)):\n            return new\n\n        collection_timestamp = self._collection[self.model.modified_field]\n\n        try:\n            jsonschema.validate(new, schema)\n            new[self.schema_field] = collection_timestamp\n        except jsonschema_exceptions.ValidationError as e:\n            field = e.path.pop() if e.path else e.validator_value.pop()\n            raise_invalid(self.request, name=field, description=e.message)\n\n        return new\n\n    def collection_get(self):\n        result = super(Record, self).collection_get()\n        self._handle_cache_expires(self.request.response)\n        return result\n\n    def get(self):\n        result = super(Record, self).get()\n        self._handle_cache_expires(self.request.response)\n        return result\n\n    def _handle_cache_expires(self, response):\n        \"\"\"If the parent collection defines a ``cache_expires`` attribute,\n        then cache-control response headers are sent.\n\n        .. note::\n\n            Those headers are also sent if the\n            ``kinto.record_cache_expires_seconds`` setting is defined.\n        \"\"\"\n        is_anonymous = Authenticated not in self.request.effective_principals\n        if not is_anonymous:\n            return\n\n        cache_expires = self._collection.get('cache_expires')\n        if cache_expires is None:\n            by_bucket = 'kinto.%s_record_cache_expires_seconds' % (\n                self.bucket_id)\n            by_collection = '%s_%s_record_cache_expires_seconds' % (\n                self.bucket_id, self.collection_id)\n            settings = self.request.registry.settings\n            cache_expires = settings.get(by_collection,\n                                         settings.get(by_bucket))\n\n        if cache_expires is not None:\n            response.cache_expires(seconds=cache_expires)\n", "path": "kinto/views/records.py"}]}