Rewrite colander schema

cornice/schemas/__init__.py

@@ -0,0 +1,91 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this file,
+# You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from __future__ import absolute_import
+
+import importlib
+
+from pyramid import path
+
+from cornice.schemas import generic
+from cornice import util
+
+
+def get_adapter(name):
+    try:
+        a = adapters[name]
+    except KeyError:
+        raise AdapterNotFoundError(name)
+    return a
+
+
+def use(schema, request):
+    schema = _apply_compat_if_required(schema)
+    schema = _python_path_resolver.maybe_resolve(schema)
+
+    for bind in _adapters:
+        try:
+            adapter = bind(schema)
+        except generic.UnsuitableSchemaCtrl:
+            continue
+
+        break
+    else:
+        raise generic.InvalidSchemaError(
+            'No schema adapter found for: {!r}'.format(schema))
+
+    payload, errors = adapter(request)
+
+    for err in errors:
+        request.errors.add(err.location, err.field, err.desc)
+    request.validated.update(payload)
+
+
+def _apply_compat_if_required(schema):
+    # only dotted name should be forced to use backward compatible adapter.
+    # Because it points to colander schema class or instance in previous
+    # releases. Without this hack, such objects will be handled by new colander
+    # adapter now.
+    if isinstance(schema, util.string_types):
+        schema = CorniceSchema.from_colander(schema)
+    return schema
+
+
+class _PredefinedAdapter(generic.GenericAdapter):
+    def __init__(self, schema):
+        super(_PredefinedAdapter, self).__init__(schema)
+        if not isinstance(self.schema, generic.GenericAdapter):
+            raise generic.UnsuitableSchemaCtrl
+
+    def __call__(self, request):
+        return self.schema(request)
+
+
+_python_path_resolver = path.DottedNameResolver(__name__)
+
+
+adapters = {}
+_adapters = [
+    _PredefinedAdapter]
+for name in ('.compat', '.colander', '.generic'):
+    try:
+        # TODO: rewrite using stevedore
+        mod = importlib.import_module(name, __name__)
+    except ImportError:
+        continue
+
+    payload = mod.init()
+    if isinstance(payload, generic.AdapterDescriptor):
+        _adapters.append(payload.adapter)
+        adapters[payload.name] = payload.adapter
+    else:
+        try:
+            _adapters.extend(payload)
+        except TypeError:
+            _adapters.append(payload)
+
+
+AdapterNotFoundError = generic.AdapterNotFoundError
+InvalidSchemaError = generic.InvalidSchemaError
+CorniceSchema = generic.CorniceSchema