buffet: Adding GCD command definition schema - phase 1.
Initial implementation of GCD command definition schema
and parsing command definition provided as JSON.
This change introduces the class hierarchy to describe
parameter type description (ParamType-derived classes),
parameter values (ParamValue-derived classes), constraints,
and general object schema which is a collection of
parameter definition for an object which corresponds
almost directly into a GCD command definition.
Object definition parsing from JSON is implemented
as well as validation of parameter values with rich
error reporting.
This is a basis for future command definition implementation
and device draft definition for GCD devices.
BUG=chromium:374860
TEST=Unit tests pass
Change-Id: I82d185b155956ff31a2d2e33f75bec9605ef32ee
Reviewed-on: https://chromium-review.googlesource.com/201159
Reviewed-by: Christopher Wiley <wiley@chromium.org>
Commit-Queue: Alex Vakulenko <avakulenko@chromium.org>
Tested-by: Alex Vakulenko <avakulenko@chromium.org>
diff --git a/buffet/commands/object_schema.h b/buffet/commands/object_schema.h
new file mode 100644
index 0000000..0e48129
--- /dev/null
+++ b/buffet/commands/object_schema.h
@@ -0,0 +1,88 @@
+// 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_OBJECT_SCHEMA_H_
+#define BUFFET_COMMANDS_OBJECT_SCHEMA_H_
+
+#include <map>
+#include <memory>
+#include <string>
+
+#include <base/basictypes.h>
+
+#include "buffet/error.h"
+
+namespace base {
+class Value;
+class DictionaryValue;
+} // namespace base
+
+namespace buffet {
+
+class PropType;
+
+// ObjectSchema is a class representing an object definition in GCD command
+// schema. This could represent a GCD command definition, but also it can be
+// used when defining custom object types for command properties such as
+// output media type (paper) for print command. The schema definition for
+// these type of object description is the same.
+class ObjectSchema final {
+ public:
+ // Properties is a string-to-PropType map representing a list of
+ // properties defined for a command/object. The key is the parameter
+ // name and the value is the parameter type definition object.
+ using Properties = std::map<std::string, std::shared_ptr<PropType>>;
+
+ ObjectSchema() = default;
+
+ // Add a new parameter definition.
+ void AddProp(const std::string& name, std::shared_ptr<PropType> prop);
+ // Finds parameter type definition by name. Returns nullptr if not found.
+ const PropType* GetProp(const std::string& name) const;
+ // Gets the list of all the properties defined.
+ const Properties& GetProps() const { return properties_; }
+
+ // Saves the object schema to JSON. When |full_schema| is set to true,
+ // then all properties and constraints are saved, otherwise, only
+ // the overridden (not inherited) ones are saved.
+ std::unique_ptr<base::DictionaryValue> ToJson(bool full_schema,
+ ErrorPtr* error) const;
+ // Loads the object schema from JSON. If |schema| is not nullptr, it is
+ // used as a base schema to inherit omitted properties and constraints from.
+ bool FromJson(const base::DictionaryValue* value, const ObjectSchema* schema,
+ ErrorPtr* error);
+
+ private:
+ // Internal helper method to load individual parameter type definitions.
+ bool PropFromJson(const std::string& prop_name,
+ const base::Value& value,
+ const PropType* schemaProp,
+ Properties* properties, ErrorPtr* error) const;
+ // Helper function in case the parameter is defined as JSON string like this:
+ // "prop":"..."
+ bool PropFromJsonString(const std::string& prop_name,
+ const base::Value& value,
+ const PropType* schemaProp,
+ Properties* properties, ErrorPtr* error) const;
+ // Helper function in case the parameter is defined as JSON array like this:
+ // "prop":[...]
+ bool PropFromJsonArray(const std::string& prop_name,
+ const base::Value& value,
+ const PropType* schemaProp,
+ Properties* properties, ErrorPtr* error) const;
+ // Helper function in case the parameter is defined as JSON object like this:
+ // "prop":{...}
+ bool PropFromJsonObject(const std::string& prop_name,
+ const base::Value& value,
+ const PropType* schemaProp,
+ Properties* properties, ErrorPtr* error) const;
+
+ // Internal parameter type definition map.
+ Properties properties_;
+ DISALLOW_COPY_AND_ASSIGN(ObjectSchema);
+};
+
+} // namespace buffet
+
+#endif // BUFFET_COMMANDS_OBJECT_SCHEMA_H_
