1 // Copyright 2015 The Weave Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef LIBWEAVE_SRC_COMPONENT_MANAGER_H_
6 #define LIBWEAVE_SRC_COMPONENT_MANAGER_H_
7 
8 #include <map>
9 #include <memory>
10 
11 #include <base/callback_list.h>
12 #include <base/time/clock.h>
13 #include <base/values.h>
14 #include <weave/error.h>
15 
16 #include "src/commands/command_queue.h"
17 
18 namespace weave {
19 
20 class CommandInstance;
21 
22 enum class UserRole {
23   kViewer,
24   kUser,
25   kManager,
26   kOwner,
27 };
28 
29 // A simple notification record event to track component state changes.
30 // The |timestamp| records the time of the state change.
31 // |changed_properties| contains a property set with the new property values
32 // which were updated at the time the event was recorded.
33 struct ComponentStateChange {
ComponentStateChangeComponentStateChange34   ComponentStateChange(base::Time time,
35                        const std::string& path,
36                        std::unique_ptr<base::DictionaryValue> properties)
37       : timestamp{time},
38         component{path},
39         changed_properties{std::move(properties)} {}
40   base::Time timestamp;
41   std::string component;
42   std::unique_ptr<base::DictionaryValue> changed_properties;
43 };
44 
45 class ComponentManager {
46  public:
47   using UpdateID = uint64_t;
48   using Token =
49       std::unique_ptr<base::CallbackList<void(UpdateID)>::Subscription>;
50   struct StateSnapshot {
51     UpdateID update_id;
52     std::vector<ComponentStateChange> state_changes;
53   };
54 
ComponentManager()55   ComponentManager() {}
~ComponentManager()56   virtual ~ComponentManager() {}
57 
58   // Loads trait definition schema.
59   virtual bool LoadTraits(const base::DictionaryValue& dict,
60                           ErrorPtr* error) = 0;
61 
62   // Same as the overload above, but takes a json string to read the trait
63   // definitions from.
64   virtual bool LoadTraits(const std::string& json, ErrorPtr* error) = 0;
65 
66   // Sets callback which is called when new trait definitions are added.
67   virtual void AddTraitDefChangedCallback(const base::Closure& callback) = 0;
68 
69   // Adds a new component instance to device.
70   // |path| is a path to the parent component (or empty string if a root-level
71   // component is being added).
72   // |name| is a component name being added.
73   // |traits| is a list of trait names this component supports.
74   virtual bool AddComponent(const std::string& path,
75                             const std::string& name,
76                             const std::vector<std::string>& traits,
77                             ErrorPtr* error) = 0;
78 
79   // Adds a new component instance to device, as a part of component array.
80   // |path| is a path to the parent component.
81   // |name| is an array root element inside the child components.
82   // |traits| is a list of trait names this component supports.
83   virtual bool AddComponentArrayItem(const std::string& path,
84                                      const std::string& name,
85                                      const std::vector<std::string>& traits,
86                                      ErrorPtr* error) = 0;
87 
88   // Removes an existing component instance from device.
89   // |path| is a path to the parent component (or empty string if a root-level
90   // component is being removed).
91   // |name| is a name of the component to be removed.
92   virtual bool RemoveComponent(const std::string& path,
93                                const std::string& name,
94                                ErrorPtr* error) = 0;
95 
96   // Removes an element from component array.
97   // |path| is a path to the parent component.
98   // |index| is a zero-based element index in the component array.
99   virtual bool RemoveComponentArrayItem(const std::string& path,
100                                         const std::string& name,
101                                         size_t index,
102                                         ErrorPtr* error) = 0;
103 
104   // Sets callback which is called when new components are added.
105   virtual void AddComponentTreeChangedCallback(
106       const base::Closure& callback) = 0;
107 
108   // Adds a new command instance to the command queue. The command specified in
109   // |command_instance| must be fully initialized and have its name, component,
110   // id populated.
111   virtual void
112   AddCommand(std::unique_ptr<CommandInstance> command_instance) = 0;
113 
114   // Parses the command definition from a json dictionary. The resulting command
115   // instance is populated with all the required fields and partially validated
116   // against syntax/schema.
117   // The new command ID is returned through optional |id| param.
118   virtual std::unique_ptr<CommandInstance> ParseCommandInstance(
119       const base::DictionaryValue& command,
120       Command::Origin command_origin,
121       UserRole role,
122       std::string* id,
123       ErrorPtr* error) = 0;
124 
125   // Find a command instance with the given ID in the command queue.
126   virtual CommandInstance* FindCommand(const std::string& id) = 0;
127 
128   // Command queue monitoring callbacks (called when a new command is added to
129   // or removed from the queue).
130   virtual void AddCommandAddedCallback(
131       const CommandQueue::CommandCallback& callback) = 0;
132   virtual void AddCommandRemovedCallback(
133       const CommandQueue::CommandCallback& callback) = 0;
134 
135   // Adds a command handler for specific component's command.
136   // |component_path| is a path to target component (e.g. "stove.burners[2]").
137   // |command_name| is a full path of the command, including trait name and
138   // command name (e.g. "burner.setPower").
139   virtual void AddCommandHandler(
140       const std::string& component_path,
141       const std::string& command_name,
142       const Device::CommandHandlerCallback& callback) = 0;
143 
144   // Finds a component instance by its full path.
145   virtual const base::DictionaryValue* FindComponent(const std::string& path,
146                                                      ErrorPtr* error) const = 0;
147   // Finds a definition of trait with the given |name|.
148   virtual const base::DictionaryValue* FindTraitDefinition(
149       const std::string& name) const = 0;
150 
151   // Finds a command definition, where |command_name| is in the form of
152   // "trait.command".
153   virtual const base::DictionaryValue* FindCommandDefinition(
154       const std::string& command_name) const = 0;
155 
156   // Checks the minimum required user role for a given command.
157   virtual bool GetMinimalRole(const std::string& command_name,
158                               UserRole* minimal_role,
159                               ErrorPtr* error) const = 0;
160 
161   // Returns the full JSON dictionary containing trait definitions.
162   virtual const base::DictionaryValue& GetTraits() const = 0;
163 
164   // Returns the full JSON dictionary containing component instances.
165   virtual const base::DictionaryValue& GetComponents() const = 0;
166 
167   // Component state manipulation methods.
168   virtual bool SetStateProperties(const std::string& component_path,
169                                   const base::DictionaryValue& dict,
170                                   ErrorPtr* error) = 0;
171   virtual bool SetStatePropertiesFromJson(const std::string& component_path,
172                                           const std::string& json,
173                                           ErrorPtr* error) = 0;
174   virtual const base::Value* GetStateProperty(const std::string& component_path,
175                                               const std::string& name,
176                                               ErrorPtr* error) const = 0;
177   virtual bool SetStateProperty(const std::string& component_path,
178                                 const std::string& name,
179                                 const base::Value& value,
180                                 ErrorPtr* error) = 0;
181 
182   virtual void AddStateChangedCallback(const base::Closure& callback) = 0;
183 
184   // Returns the recorded state changes since last time this method was called.
185   virtual StateSnapshot GetAndClearRecordedStateChanges() = 0;
186 
187   // Called to notify that the state patch with |id| has been successfully sent
188   // to the server and processed.
189   virtual void NotifyStateUpdatedOnServer(UpdateID id) = 0;
190 
191   // Returns an ID of last state change update. Each SetStatePropertyNNN()
192   // invocation increments this value by 1.
193   virtual UpdateID GetLastStateChangeId() const = 0;
194 
195   // Subscribes for device state update notifications from cloud server.
196   // The |callback| will be called every time a state patch with given ID is
197   // successfully received and processed by Weave server.
198   // Returns a subscription token. As soon as this token is destroyed, the
199   // respective callback is removed from the callback list.
200   virtual Token AddServerStateUpdatedCallback(
201       const base::Callback<void(UpdateID)>& callback) = 0;
202 
203   // Helper method for legacy API to obtain first component that implements
204   // the given trait. This is useful for routing commands that have no component
205   // path specified.
206   // Returns empty string if no components are found.
207   // This method only searches for component on the top level of components
208   // tree. No sub-components are searched.
209   virtual std::string FindComponentWithTrait(
210       const std::string& trait) const = 0;
211 
212   // Support for legacy APIs. Setting command and state definitions.
213   // This translates into modifying a trait definition.
214   virtual bool AddLegacyCommandDefinitions(const base::DictionaryValue& dict,
215                                            ErrorPtr* error) = 0;
216   virtual bool AddLegacyStateDefinitions(const base::DictionaryValue& dict,
217                                          ErrorPtr* error) = 0;
218   // Returns device state for legacy APIs.
219   virtual const base::DictionaryValue& GetLegacyState() const = 0;
220   // Returns command definitions for legacy APIs.
221   virtual const base::DictionaryValue& GetLegacyCommandDefinitions() const = 0;
222 
223   DISALLOW_COPY_AND_ASSIGN(ComponentManager);
224 };
225 
226 }  // namespace weave
227 
228 #endif  // LIBWEAVE_SRC_COMPONENT_MANAGER_H_
229