Class Event

• Defined in File Event.hpp

Nested Relationships

Nested Types

• Class Event::Active

• Class Event::Initializer

• Class Event::Standby

Inheritance Relationships

Base Type

• public rmf_task::Event

Derived Type

• public rmf_task_sequence::events::Bundle (Class Bundle)

Class Documentation

class Event : public rmf_task::Event

Subclassed by rmf_task_sequence::events::Bundle

Public Types

using ActivePtr = std::shared_ptr<Active>

using Description = Activity::Description

using ConstDescriptionPtr = std::shared_ptr<const Description>

using StandbyPtr = std::shared_ptr<Standby>

using InitializerPtr = std::shared_ptr<Initializer>

using ConstInitializerPtr = std::shared_ptr<const Initializer>

class Active : public rmf_task_sequence::Activity::Active

Public Functions

virtual ConstStatePtr state() const = 0

Get the state of this event. The state object returned by this function must always be the same state object, and it must remain the same state object that would have been provided by the Event::Standby that kicked off this Event::Active.

virtual rmf_traffic::Duration remaining_time_estimate() const = 0

Estimate how much longer this event will take to complete.

virtual ~Active() = default

class Initializer

The Event::Initializer class is the Event equivalent to the rmf_task::Activator class. It consumes an Event::Description and produces

Public Types

template<typename Description>
using Initialize = std::function<StandbyPtr(const AssignIDPtr &id, const std::function<rmf_task::State()> &get_state, const ConstParametersPtr &parameters, const Description &description, std::function<void()> update)>

Signature for initializing an Event

Warning

The update function must not be triggered during initialization because upstream event handlers will not be ready to handle it. The event state will always be checked right after initialization is finished anyway, so there is no need to trigger this.

Template Parameters:

Description – A class that implements the Event::Description interface

Param id:

[in] An object to help assign an ID to each event

Param get_state:

[in] A callback for retrieving the current state of the robot

Param parameters:

[in] A reference to the parameters for the robot

Param description:

[in] The down-casted description of the event

Param backup_state:

[in] The serialized backup state of the Event, if the Event is being restored from a crash or disconnection. If the Event is not being restored, a std::nullopt will be passed in here.

Param update:

[in] A callback that will be triggered when a notable change happens for this event.

Return:

an Event in a Standby state

template<typename Description>
using Restore = std::function<ActivePtr(const AssignIDPtr &id, const std::function<rmf_task::State()> &get_state, const ConstParametersPtr &parameters, const Description &description, const nlohmann::json &backup_state, std::function<void()> update, std::function<void()> checkpoint, std::function<void()> finished)>

Signature for restoring an Event

Warning

The update function must not be triggered during initialization because upstream event handlers will not be ready to handle it. The event state will always be checked right after initialization is finished anyway, so there is no need to trigger this.

Template Parameters:

Description – A class that implements the Event::Description interface

Param id:

[in] An object to help assign an ID to each event

Param get_state:

[in] A callback for retrieving the current state of the robot

Param parameters:

[in] A reference to the parameters for the robot

Param description:

[in] The down-casted description of the event

Param backup_state:

[in] The backup state of the Event.

Param update:

[in] A callback that will be triggered when a notable change happens for this event.

Param checkpoint:

[in] A callback that will be triggered when the event reaches a “checkpoint” meaning that the task state should be backed up.

Param finished:

[in] A callback that will be triggered when the event reaches a Finished state

Return:

a restored Event in an Active state

Public Functions

Initializer()

Construct an empty Initializer.

template<typename Desc>
void add(Initialize<Desc> initializer, Restore<Desc> restorer)

Add a callback to convert from a Description to an event in standby mode.

StandbyPtr initialize(const AssignIDPtr &id, const std::function<rmf_task::State()> &get_state, const ConstParametersPtr &parameters, const Event::Description &description, std::function<void()> update) const

Initialize an event

Warning

The update function must not be triggered during initialization because upstream event handlers will not be ready to handle it. The event state will always be checked right after initialization is finished anyway, so there is no need to trigger this.

Parameters:

• id – [in] An object to help assign an ID to each event

• get_state – [in] A callback for retrieving the current state of the robot

• parameters – [in] A reference to the parameters for the robot

• description – [in] The description of the event

• update – [in] A callback that will be triggered when a notable change happens for this event.

Returns:

an Event in a Standby state

ActivePtr restore(const AssignIDPtr &id, const std::function<rmf_task::State()> &get_state, const ConstParametersPtr &parameters, const Event::Description &description, const nlohmann::json &backup, std::function<void()> update, std::function<void()> checkpoint, std::function<void()> finished) const

Signature for restoring an Event

Warning

The update function must not be triggered during initialization because upstream event handlers will not be ready to handle it. The event state will always be checked right after initialization is finished anyway, so there is no need to trigger this.

Parameters:

• id – [in] An object to help assign an ID to each event

• get_state – [in] A callback for retrieving the current state of the robot

• parameters – [in] A reference to the parameters for the robot

• description – [in] The down-casted description of the event

• backup_state – [in] The backup state of the Event.

• update – [in] A callback that will be triggered when a notable change happens for this event.

• checkpoint – [in] A callback that will be triggered when the event reaches a “checkpoint” meaning that the task state should be backed up.

• finished – [in] A callback that will be triggered when the event reaches a Finished state

Returns:

a restored Event in an Active state

class Standby

The interface of an event that is in a standby mode. This interface is what will be provided by the Event::Initializer. When the right conditions are met for the event to begin, the owner of the event should trigger the begin() function.

Public Functions

virtual ConstStatePtr state() const = 0

Get the state of this event. The state object returned by this function must always be the same state object, and it must remain the relevant state object for this Event after begin(~) has been called.

virtual rmf_traffic::Duration duration_estimate() const = 0

Estimate how long this event will take once it has started.

virtual ActivePtr begin(std::function<void()> checkpoint, std::function<void()> finished) = 0

Tell this event to begin. This function should be implemented to always return the same Event::Active instance if it gets called more than once.

Parameters:

• checkpoint – [in] A callback that will be triggered when the event reaches a “checkpoint” meaning that the task state should be backed up.

• finished – [in] A callback that will be triggered when the event reaches a Finished state

virtual ~Standby() = default