buffet: GCD command defintion. Compound object type support.
Added support for "object" type. Refactored parameter validation
to make sure we have object schema context when we validate
a value of parameter.
Parameter |schema| was used in two different contexts, as both
a base parameter definition and as a custom object definition.
Renamed the former to be 'base_schema' and latter as
'object_schema' to remove the confusion.
Extracted common data type manipulation functions into
schema_utils.cc/.h files.
BUG=chromium:374860
TEST=All unit tests pass.
Change-Id: I6c3549849a258bcc94b3d754acd14e072438d140
Reviewed-on: https://chromium-review.googlesource.com/204793
Tested-by: Alex Vakulenko <avakulenko@chromium.org>
Reviewed-by: Christopher Wiley <wiley@chromium.org>
Commit-Queue: Alex Vakulenko <avakulenko@chromium.org>
diff --git a/buffet/commands/schema_utils.h b/buffet/commands/schema_utils.h
new file mode 100644
index 0000000..ff9d461
--- /dev/null
+++ b/buffet/commands/schema_utils.h
@@ -0,0 +1,118 @@
+// Copyright 2014 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BUFFET_COMMANDS_SCHEMA_UTILS_H_
+#define BUFFET_COMMANDS_SCHEMA_UTILS_H_
+
+#include <limits>
+#include <map>
+#include <memory>
+#include <string>
+#include <type_traits>
+#include <vector>
+
+#include <base/values.h>
+
+#include <buffet/error.h>
+
+namespace buffet {
+
+class PropValue;
+class ObjectSchema;
+
+namespace native_types {
+// C++ representation of object values.
+using Object = std::map<std::string, std::shared_ptr<PropValue>>;
+} // namespace native_types
+// Converts an object to string.
+std::string ToString(const native_types::Object& obj);
+
+// InheritableAttribute class is used for specifying various command parameter
+// attributes that can be inherited from a base (parent) schema.
+// The |value| still specifies the actual attribute values, whether it
+// is inherited or overridden, while |is_inherited| can be used to identify
+// if the attribute was inherited (true) or overridden (false).
+template<typename T>
+class InheritableAttribute {
+ public:
+ InheritableAttribute() = default;
+ explicit InheritableAttribute(T val)
+ : value(std::move(val)), is_inherited(true) {}
+ InheritableAttribute(T val, bool inherited)
+ : value(std::move(val)), is_inherited(inherited) {}
+ T value{};
+ bool is_inherited{true};
+};
+
+// A bunch of helper function to create base::Value for specific C++ classes,
+// including vectors of types. These are used in template classes below
+// to simplify specialization logic.
+std::unique_ptr<base::Value> TypedValueToJson(bool value, ErrorPtr* error);
+std::unique_ptr<base::Value> TypedValueToJson(int value, ErrorPtr* error);
+std::unique_ptr<base::Value> TypedValueToJson(double value, ErrorPtr* error);
+std::unique_ptr<base::Value> TypedValueToJson(const std::string& value,
+ ErrorPtr* error);
+std::unique_ptr<base::Value> TypedValueToJson(const native_types::Object& value,
+ ErrorPtr* error);
+template<typename T>
+std::unique_ptr<base::Value> TypedValueToJson(const std::vector<T>& values,
+ ErrorPtr* error) {
+ std::unique_ptr<base::ListValue> list(new base::ListValue);
+ for (const auto& v : values) {
+ auto json = TypedValueToJson(v, error);
+ if (!json)
+ return std::unique_ptr<base::Value>();
+ list->Append(json.release());
+ }
+ return std::move(list);
+}
+
+// Similarly to CreateTypedValue() function above, the following overloaded
+// helper methods allow to extract specific C++ data types from base::Value.
+// Also used in template classes below to simplify specialization logic.
+bool TypedValueFromJson(const base::Value* value_in,
+ const ObjectSchema* object_schema,
+ bool* value_out, ErrorPtr* error);
+bool TypedValueFromJson(const base::Value* value_in,
+ const ObjectSchema* object_schema,
+ int* value_out, ErrorPtr* error);
+bool TypedValueFromJson(const base::Value* value_in,
+ const ObjectSchema* object_schema,
+ double* value_out, ErrorPtr* error);
+bool TypedValueFromJson(const base::Value* value_in,
+ const ObjectSchema* object_schema,
+ std::string* value_out, ErrorPtr* error);
+bool TypedValueFromJson(const base::Value* value_in,
+ const ObjectSchema* object_schema,
+ native_types::Object* value_out, ErrorPtr* error);
+
+bool operator==(const native_types::Object& obj1,
+ const native_types::Object& obj2);
+
+// CompareValue is a helper function to help with implementing EqualsTo operator
+// for various data types. For most scalar types it is using operator==(),
+// however, for floating point values, rounding errors in binary representation
+// of IEEE floats/doubles can cause straight == comparison to fail for seemingly
+// equivalent values. For these, use approximate comparison with the error
+// margin equal to the epsilon value defined for the corresponding data type.
+// This is used when looking up values for implementation of OneOf constraints
+// which should work reliably for floating points also ("number" type).
+
+// Compare exact types using ==.
+template<typename T>
+inline typename std::enable_if<!std::is_floating_point<T>::value, bool>::type
+CompareValue(const T& v1, const T& v2) {
+ return v1 == v2;
+}
+
+// Compare non-exact types (such as double) using precision margin (epsilon).
+template<typename T>
+inline typename std::enable_if<std::is_floating_point<T>::value, bool>::type
+CompareValue(const T& v1, const T& v2) {
+ return std::abs(v1 - v2) <= std::numeric_limits<T>::epsilon();
+}
+
+} // namespace buffet
+
+#endif // BUFFET_COMMANDS_SCHEMA_UTILS_H_
