Reading, writing of CDD and CJT JSON formats.

components/cloud_devices/description_items.h

+// Copyright 2014 The Chromium 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 COMPONENTS_CLOUD_DEVICES_CAPABILITY_INTERFACES_H_
+#define COMPONENTS_CLOUD_DEVICES_CAPABILITY_INTERFACES_H_
+
+// Defines common templates that could be used to create device specific
+// capabilities and print tickets.
+
+#include <vector>
+
+#include "base/logging.h"
+
+#include "components/cloud_devices/cloud_device_description.h"
+
+namespace base {
+class DictionaryValue;
+}
+
+namespace cloud_devices {
+
+// All traits below specify how to serialize and validate capabilities and
+// ticket items.
+// Traits should have following methods:
+//   // Returns true if capability semantically valid.
+//   static bool IsValid(const Option&);
+//
+//   // Returns json path relative to the root of CDD/CJT.
+//   static std::string GetItemPath();
+//
+//   // Loads ticket item. Returns false if failed.
+//   static bool Load(const base::DictionaryValue& dict, ContentType* option);
+//
+//   // Saves ticket item.
+//   static void Save(ContentType option, base::DictionaryValue* dict);
+
+// Represents a CDD capability that is stored as a JSON list
+// Ex: "<CAPABILITY_NAME>": [ {<VALUE>}, {<VALUE>}, {<VALUE>} ]
+// Option specifies data type for <VALUE>.
+// Traits specifies how <VALUE> is stored in JSON and semantic validation.
+template <class Option, class Traits>
+class ListCapability {
+ public:
+  ListCapability();
+  ~ListCapability();
+
+  bool LoadFrom(const CloudDeviceDescription& description);
+  void SaveTo(CloudDeviceDescription* description) const;
+
+  void Reset() {
+    options_.clear();
+  }
+
+  bool IsValid() const;
+
+  bool empty() const {
+    return options_.empty();
+  }
+
+  size_t size() const {
+    return options_.size();
+  }
+
+  const Option& operator[](size_t i) const {
+    return options_[i];
+  }
+
+  bool Contains(const Option& option) const{
+    return std::find(options_.begin(), options_.end(), option) !=
+           options_.end();
+  }
+
+  void AddOption(const Option& option) {
+    options_.push_back(option);
+  }
+
+ private:
+  typedef std::vector<Option> OptionVector;
+  OptionVector options_;
+
+  DISALLOW_COPY_AND_ASSIGN(ListCapability);
+};
+
+// Represents CDD capability stored as JSON list with default_value value.
+// Ex: "<CAPABILITY_NAME>": { "option": [{ "is_default": true, <VALUE>},
+//                                       {<VALUE>} ]}
+// Option specifies data type for <VALUE>.
+// Traits specifies how <VALUE> is stored in JSON and semantic validation.
+template <class Option, class Traits>
+class SelectionCapability {
+ public:
+  SelectionCapability();
+  ~SelectionCapability();
+
+  bool LoadFrom(const CloudDeviceDescription& description);
+  void SaveTo(CloudDeviceDescription* description) const;
+
+  void Reset() {
+    options_.clear();
+    default_idx_ = -1;
+  }
+
+  bool IsValid() const;
+
+  bool empty() const {
+    return options_.empty();
+  }
+
+  size_t size() const {
+    return options_.size();
+  }
+
+  const Option& operator[](size_t i) const {
+    return options_[i];
+  }
+
+  bool Contains(const Option& option) const{
+    return std::find(options_.begin(), options_.end(), option) !=
+           options_.end();
+  }
+
+  const Option& GetDefault() const {
+    CHECK_GE(default_idx_, 0);
+    return options_[default_idx_];
+  }
+
+  void AddOption(const Option& option) {
+    AddDefaultOption(option, false);
+  }
+
+  void AddDefaultOption(const Option& option, bool is_default) {
+    options_.push_back(option);
+    if (is_default) {
+      DCHECK_EQ(default_idx_, -1);
+      // Point to the last element.
+      default_idx_ = size() - 1;
+    }
+  }
+
+ private:
+  typedef std::vector<Option> OptionVector;
+
+  OptionVector options_;
+  int default_idx_;
+
+  DISALLOW_COPY_AND_ASSIGN(SelectionCapability);
+};
+
+// Represents CDD capability that can be true or false.
+// Ex: "<CAPABILITY_NAME>": { "default_value": true }
+// Traits specifies how <VALUE> is stored in JSON and semantic validation.
+template <class Traits>
+class BooleanCapability {
+ public:
+  BooleanCapability();
+  ~BooleanCapability();
+
+  bool LoadFrom(const CloudDeviceDescription& description);
+  void SaveTo(CloudDeviceDescription* description) const;
+
+  void Reset() {
+    default_value_ = false;
+  }
+
+  void set_default_value(bool value) {
+    default_value_ = value;
+  }
+
+  bool default_value() const {
+    return default_value_;
+  }
+
+ private:
+  bool default_value_;
+
+  DISALLOW_COPY_AND_ASSIGN(BooleanCapability);
+};
+
+// Represents CDD capability for which existence is only important.
+// Ex: "<CAPABILITY_NAME>": { }
+// Traits specifies how <VALUE> is stored in JSON and semantic validation.
+template <class Traits>
+class EmptyCapability {
+ public:
+  EmptyCapability() {};
+  ~EmptyCapability() {};
+
+  bool LoadFrom(const CloudDeviceDescription& description);
+  void SaveTo(CloudDeviceDescription* description) const;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(EmptyCapability);
+};
+
+// Represents CJT items.
+// Ex: "<CAPABILITY_NAME>": {<VALUE>}
+// Option specifies data type for <VALUE>.
+// Traits specifies how <VALUE> is stored in JSON and semantic validation.
+template <class Option, class Traits>
+class TicketItem {
+ public:
+  TicketItem();
+  ~TicketItem();
+
+  bool LoadFrom(const CloudDeviceDescription& description);
+  void SaveTo(CloudDeviceDescription* description) const;
+
+  void Reset() {
+    value_ = Option();
+  }
+
+  bool IsValid() const;
+
+  const Option& value() const {
+    return value_;
+  }
+
+  void set_value(const Option& value) {
+    value_ = value;
+  }
+
+ private:
+  Option value_;
+
+  DISALLOW_COPY_AND_ASSIGN(TicketItem);
+};
+
+}  // namespace cloud_devices
+
+#endif  // COMPONENTS_CLOUD_DEVICES_CAPABILITY_INTERFACES_H_