server.interfaces.AbstractSkill

class documentation

class AbstractSkill(AbstractCallable):

Skill interface for internal and external OPC UA access.

Async Method	`halt`	Halt (Stop) the skill. Machine internal interface.
Async Method	`reset`	Reset the skill. Machine internal interface.
Async Method	`start`	Start the skill. Machine internal interface.
Async Method	`suspend`	Suspend the skill (if the skill is suspendable). Machine internal interface.
Async Method	`wait_for_state`	Blocks until this skill either reached the given `state` or was unexpectedly halted.
Property	`current_state`	Current state of the skill.
Property	`is_finite`	Return `True` if this skill is finite.
Property	`name`	Name of the skill.
Property	`ua_state_machine`	OPC UA base node of state machine.
Async Method	`_condition_is_suspendable`	Check whether this skill is suspendable.
Async Method	`_get_definition`	Return the instantiation definition for the main OPC UA node. Is called from `ua_create_node`.
Async Method	`_ua_halt`	Handle the OPC UA `halt` method invocation.
Async Method	`_ua_reset`	Handle the OPC UA `reset` method invocation.
Async Method	`_ua_start`	Handle the OPC UA `start` method invocation.
Async Method	`_ua_suspend`	Handle the OPC UA `suspend` method invocation.

Inherited from AbstractCallable:

Async Method	`_condition_access_allowed`	Check if the provided `user` has access to this skill.
Async Method	`_condition_dependencies_ready`	Check whether ALL dependencies are ready (different meaning for different types).
Async Method	`_condition_startup_completed`	Check whether the parent component/machine startup is completed.

Inherited from AbstractUaObject (via AbstractCallable):

Method	`access_allowed`	Check whether `user` is currently allowed access to this `UaObject`.
Async Method	`condition_as_dependency_ready`	Check whether this object is ready as a dependency in composite skills, etc.
Property	`full_name`	Return the full name including the names of all parents, separated by '/'.
Property	`lock`	`Lock` instance protecting this `UaObject`.
Property	`logger`	Logger associated with the `UaObject` instance.
Property	`path`	Return the full path of the object.
Property	`server`	Server instance.
Property	`ua_node`	Raw OPC UA node.

@abstractmethod

async def halt(self): ¶

Halt (Stop) the skill. Machine internal interface.

Similar to calling the OPC UA method halt(), except that exceptions are not handled.

@abstractmethod

async def reset(self): ¶

Reset the skill. Machine internal interface.

Similar to calling the OPC UA method reset(), except that exceptions are not handled.

@abstractmethod

async def start(self): ¶

Start the skill. Machine internal interface.

Similar to calling the OPC UA method start(), except that exceptions are not handled.

@abstractmethod

async def suspend(self): ¶

Suspend the skill (if the skill is suspendable). Machine internal interface.

Similar to calling the OPC UA method suspend(), except that exceptions are not handled.

@abstractmethod

async def wait_for_state(self, state: SkillState): ¶

Blocks until this skill either reached the given state or was unexpectedly halted.

Parameters
state:`SkillState`	the state of this skill to wait for.

Raises
`SkillHaltedError`	If skill has unexpectedly halted.

@property
@abstractmethod

current_state: SkillState = ¶

Current state of the skill.

@property
@abstractmethod

is_finite: bool = ¶

Return True if this skill is finite.

This must be correct regardless where the logic is implemented (PLC, Remote, etc. vs. this Python instance).

@property
@abstractmethod

name: str = ¶

overrides server.interfaces.AbstractUaObject.name

Name of the skill.

@property
@abstractmethod

ua_state_machine: Node = ¶

OPC UA base node of state machine.

@abstractmethod

async def _condition_is_suspendable(self, _user: UserAuthorization) -> bool: ¶

Check whether this skill is suspendable.

Returns
`bool`	Always `True`, else an exception is raised.

Raises
`UaStatusCodeError`	If the skill is not suspendable.

@abstractmethod

async def _get_definition(self) -> UaObjectDefinition: ¶

Return the instantiation definition for the main OPC UA node. Is called from ua_create_node.

@uamethod
@abstractmethod

async def _ua_halt(self, _parent: NodeId, session: SessionProtocol) -> ua.StatusCode: ¶

Handle the OPC UA halt method invocation.

This callback is executed when an OPC UA client calls the halt method. Do not raise exceptions here, instead return the appropriate OPC UA status code!

Parameters
_parent:`NodeId`	Parent OPC UA `NodeId`.
session:`SessionProtocol`	OPC UA Client session that issued the method request.

Returns
`ua.StatusCode`	Undocumented

@uamethod
@abstractmethod

async def _ua_reset(self, _parent: NodeId, session: SessionProtocol) -> ua.StatusCode: ¶

Handle the OPC UA reset method invocation.

This callback is executed when an OPC UA client calls the reset method. Do not raise exceptions here, instead return the appropriate OPC UA status code!

Parameters
_parent:`NodeId`	Parent OPC UA `NodeId`.
session:`SessionProtocol`	OPC UA Client session that issued the method request.

Returns
`ua.StatusCode`	Undocumented

@uamethod
@abstractmethod

async def _ua_start(self, _parent: NodeId, session: SessionProtocol) -> ua.StatusCode: ¶

Handle the OPC UA start method invocation.

This callback is executed when an OPC UA client calls the start method. Do not raise exceptions here, instead return the appropriate OPC UA status code!

Parameters
_parent:`NodeId`	Parent OPC UA `NodeId`.
session:`SessionProtocol`	OPC UA Client session that issued the method request.

Returns
`ua.StatusCode`	Undocumented

@uamethod
@abstractmethod

async def _ua_suspend(self, _parent: NodeId, session: SessionProtocol) -> ua.StatusCode: ¶

Handle the OPC UA suspend method invocation.

This callback is executed when an OPC UA client calls the suspend method. Do not raise exceptions here, instead return the appropriate OPC UA status code!

Parameters
_parent:`NodeId`	Parent OPC UA `NodeId`.
session:`SessionProtocol`	OPC UA Client session that issued the method request.

Returns
`ua.StatusCode`	Undocumented