Scenario class

Bases: _Entity, Submittable, _Labeled

Instance of a Business case to solve.

A scenario holds a set of tasks (instances of Task class) to submit for execution in order to solve the Business case. Each task can be connected to some data nodes as input or output forming an execution graph. The scenario can be submitted for execution, and the tasks will be orchestrated to solve the Business case.
A scenario also holds a set of additional data nodes (instances of DataNode class) for extra data related to the scenario.

Note

It is not recommended to instantiate a Scenario directly. Instead, it should be created with the create_scenario() function.

Example

import taipy as tp
from taipy import Config

def by_two(x: int):
    return x * 2

if __name__ == "__main__":
    # Configure scenarios
    input_cfg = Config.configure_data_node("my_input")
    result_cfg = Config.configure_data_node("my_result")
    task_cfg = Config.configure_task("my_double", function=by_two, input=input_cfg, output=result_cfg)
    scenario_cfg = Config.configure_scenario("my_scenario", task_configs=[task_cfg])

    # Create a new scenario from the configuration
    scenario = tp.create_scenario(scenario_cfg)

    # Write the input data and submit the scenario
    scenario.my_input.write(3)
    scenario.submit()

    # Read the result
    print(scenario.my_result.read())  # Output: 6

    # Retrieve all scenarios
    all_scenarios = tp.get_scenarios()

Attributes¶

additional_data_nodes `property` `writable` ¶

additional_data_nodes: Dict[str, DataNode]

The dictionary of the scenario's additional data nodes.

Additional data nodes are data nodes that are not part of the scenario's graph but are used to store extra data. They are not connected to the scenario's tasks.

config_id `property` ¶

config_id: str

The identifier of the ScenarioConfig.

creation_date `property` `writable` ¶

creation_date: datetime

The date and time of the scenario's creation.

cycle `property` `writable` ¶

cycle: Optional[Cycle]

The cycle of the scenario

data_nodes `property` ¶

data_nodes: Dict[str, DataNode]

The dictionary of the scenario's data nodes.

id `instance-attribute` ¶

id: ScenarioId = scenario_id or _new_id(config_id)

The unique identifier of this scenario.

is_primary `property` `writable` ¶

is_primary: bool

True if the scenario is the primary of its cycle. False otherwise.

name `property` `writable` ¶

name: Optional[str]

The human-readable name of the scenario.

owner_id `property` ¶

owner_id: Optional[str]

The identifier of the scenario cycle.

properties `property` ¶

properties: _Properties

The dictionary of additional properties.

sequences `property` `writable` ¶

sequences: Dict[str, Sequence]

The dictionary of the scenario's sequences.

The sequences are subsets of tasks that can be submitted together independently of the rest of the scenario's tasks.

subscribers `property` `writable` ¶

subscribers: _ListAttributes

The list of callbacks to be called on Job's status change.

tags `property` `writable` ¶

tags: Set[str]

The set of scenario's tags.

tasks `property` `writable` ¶

tasks: Dict[str, Task]

The dictionary of the scenario's tasks.

version `property` ¶

version: str

The application version of the scenario.

The string indicates the application version of the scenario. If not provided, the latest version is used.

Methods¶

add_sequence() ¶

add_sequence(
    name: str,
    tasks: Union[List[Task], List[TaskId]],
    properties: Optional[Dict] = None,
    subscribers: Optional[List[_Subscriber]] = None,
) -> None

Add a sequence to the scenario.

Parameters:

Name	Type	Description	Default
`name`	`str`	The name of the sequence.	required
`tasks`	`Union[List[Task], List[TaskId]]`	The list of scenario's tasks to add to the sequence.	required
`properties`	`Optional[Dict]`	The optional properties of the sequence.	`None`
`subscribers`	`Optional[List[_Subscriber]]`	The optional list of callbacks to be called on `Job`'s status change.	`None`

Raises:

Type	Description
`SequenceTaskDoesNotExistInScenario`	If a task in the sequence does not exist in the scenario.
`SequenceAlreadyExists`	If a sequence with the same name already exists in the scenario.

add_sequences() ¶

add_sequences(
    sequences: Dict[str, Union[List[Task], List[TaskId]]]
) -> None

Add multiple sequences to the scenario.

Note

To provide properties and subscribers for the sequences, use Scenario.add_sequence instead.

Parameters:

Name	Type	Description	Default
`sequences`	`Dict[str, Union[List[Task], List[TaskId]]]`	A dictionary containing sequences to add. Each key is a sequence name, and the value must be a list of the scenario tasks.	required

Raises:

Type	Description
`SequenceTaskDoesNotExistInScenario`	If a task in the sequence does not exist in the scenario.

add_tag() ¶

add_tag(tag: str) -> None

Add a tag to this scenario.

If the scenario's cycle already have another scenario tagged with tag the other scenario will be untagged.

Parameters:

Name	Type	Description	Default
`tag`	`str`	The tag to add to this scenario.	required

data_nodes_being_edited() ¶

data_nodes_being_edited() -> Set[DataNode]

Return the set of data nodes that are being edited.

Returns:

Type	Description
`Set[DataNode]`	The set of data nodes that are being edited.

get_inputs() ¶

get_inputs() -> Set[DataNode]

Return the set of input data nodes of this submittable.

Returns:

Type	Description
`Set[DataNode]`	The set of input data nodes.

get_intermediate() ¶

get_intermediate() -> Set[DataNode]

Return the set of intermediate data nodes of the submittable entity.

Returns:

Type	Description
`Set[DataNode]`	The set of intermediate data nodes.

get_label() ¶

get_label() -> str

Returns the scenario simple label prefixed by its owner label.

Returns:

Type	Description
`str`	The label of the scenario as a string.

get_outputs() ¶

get_outputs() -> Set[DataNode]

Return the set of output data nodes of the submittable entity.

Returns:

Type	Description
`Set[DataNode]`	The set of output data nodes.

get_simple_label() ¶

get_simple_label() -> str

Returns the scenario simple label.

Returns:

Type	Description
`str`	The simple label of the scenario as a string.

has_tag() ¶

has_tag(tag: str) -> bool

Indicate if the scenario has a given tag.

Parameters:

Name	Type	Description	Default
`tag`	`str`	The tag to search among the set of scenario's tags.	required

Returns:

Type	Description
`bool`	True if the scenario has the tag given as parameter. False otherwise.

is_deletable() ¶

is_deletable() -> ReasonCollection

Indicate if the scenario can be deleted.

Returns:

Type	Description
`ReasonCollection`	True if the scenario can be deleted. False otherwise.

is_ready_to_run() ¶

is_ready_to_run() -> ReasonCollection

Indicate if the entity is ready to be run.

Returns:

Type	Description
`ReasonCollection`	A ReasonCollection object that can function as a Boolean value, which is True if the given entity is ready to be run or there is no reason to be blocked, False otherwise.

remove_sequence() ¶

remove_sequence(name: str) -> None

Remove a sequence from the scenario.

Parameters:

Name	Type	Description	Default
`name`	`str`	The name of the sequence to remove.	required

remove_sequences() ¶

remove_sequences(sequence_names: List[str]) -> None

Remove multiple sequences from the scenario.

Parameters:

Name	Type	Description	Default
`sequence_names`	`List[str]`	A list of sequence names to remove.	required

remove_tag() ¶

remove_tag(tag: str) -> None

Remove a tag from this scenario.

Parameters:

Name	Type	Description	Default
`tag`	`str`	The tag to remove from the set of the scenario's tags.	required

rename_sequence() ¶

rename_sequence(old_name, new_name) -> None

Rename a scenario sequence.

Parameters:

Name	Type	Description	Default
`old_name`	`str`	The current name of the sequence to rename.	required
`new_name`	`str`	The new name of the sequence.	required

Raises:

Type	Description
`SequenceAlreadyExists`	If a sequence with the same name already exists in the scenario.

set_primary() ¶

set_primary() -> None

Promote the scenario as the primary scenario of its cycle.

If the cycle already has a primary scenario, it will be demoted, and it will no longer be primary for the cycle.

submit() ¶

submit(
    callbacks: Optional[List[Callable]] = None,
    force: bool = False,
    wait: bool = False,
    timeout: Optional[Union[float, int]] = None,
    **properties
) -> Submission

Submit this scenario for execution.

All the Tasks of the scenario will be submitted for execution.

Parameters:

Name	Type	Description	Default
`callbacks`	`List[Callable]`	The list of callable functions to be called on status change.	`None`
`force`	`bool`	Force execution even if the data nodes are in cache.	`False`
`wait`	`bool`	Wait for the orchestrated jobs created from the scenario submission to be finished in asynchronous mode.	`False`
`timeout`	`Union[float, int]`	The optional maximum number of seconds to wait for the jobs to be finished before returning. If not provided and wait is True, the function waits indefinitely.	`None`
`**properties`	`dict[str, any]`	A keyworded variable length list of additional arguments.	`{}`

Returns:

Type	Description
`Submission`	A `Submission` containing the information of the submission.

subscribe(
    callback: Callable[[Scenario, Job], None],
    params: Optional[List[Any]] = None,
) -> None

Subscribe a function to be called on Job status change.

The subscription is applied to all jobs created from the scenario's execution.

Note

Notification will be available only for jobs created after this subscription.

Parameters:

Name	Type	Description	Default
`callback`	`Callable[[Scenario, Job], None]`	The callable function to be called on status change.	required
`params`	`Optional[List[Any]]`	The parameters to be passed to the callback.	`None`

unsubscribe() ¶

unsubscribe(
    callback: Callable[[Scenario, Job], None],
    params: Optional[List[Any]] = None,
) -> None

Unsubscribe a function that is called when the status of a Job changes.

Note

The function will continue to be called for ongoing jobs.

Parameters:

Name	Type	Description	Default
`callback`	`Callable[[Scenario, Job], None]`	The callable function to unsubscribe.	required
`params`	`Optional[List[Any]]`	The parameters to be passed to the callback.	`None`

update_sequence() ¶

update_sequence(
    name: str,
    tasks: Union[List[Task], List[TaskId]],
    properties: Optional[Dict] = None,
    subscribers: Optional[List[_Subscriber]] = None,
) -> None

Update an existing sequence.

Parameters:

Name	Type	Description	Default
`name`	`str`	The name of the sequence to update.	required
`tasks`	`Union[List[Task], List[TaskId]]`	The new list of scenario's tasks.	required
`properties`	`Optional[Dict]`	The new properties of the sequence.	`None`
`subscribers`	`Optional[List[_Subscriber]]`	The new list of callbacks to be called on `Job`'s status change.	`None`

Raises:

Type	Description
`SequenceTaskDoesNotExistInScenario`	If a task in the list does not exist in the scenario.
`SequenceAlreadyExists`	If a sequence with the same name already exists in the scenario.

Scenario class

Attributes¶

additional_data_nodes property writable ¶

config_id property ¶

creation_date property writable ¶

cycle property writable ¶

data_nodes property ¶

id instance-attribute ¶

is_primary property writable ¶

name property writable ¶

owner_id property ¶

properties property ¶

sequences property writable ¶

subscribers property writable ¶

tags property writable ¶

tasks property writable ¶

version property ¶

Methods¶

add_sequence() ¶

add_sequences() ¶

add_tag() ¶

data_nodes_being_edited() ¶

get_inputs() ¶

get_intermediate() ¶

get_label() ¶

get_outputs() ¶

get_simple_label() ¶

has_tag() ¶

is_deletable() ¶

is_ready_to_run() ¶

remove_sequence() ¶

remove_sequences() ¶

remove_tag() ¶

rename_sequence() ¶

set_primary() ¶

submit() ¶

subscribe() ¶

unsubscribe() ¶

update_sequence() ¶

additional_data_nodes `property` `writable` ¶

config_id `property` ¶

creation_date `property` `writable` ¶

cycle `property` `writable` ¶

data_nodes `property` ¶

id `instance-attribute` ¶

is_primary `property` `writable` ¶

name `property` `writable` ¶

owner_id `property` ¶

properties `property` ¶

sequences `property` `writable` ¶

subscribers `property` `writable` ¶

tags `property` `writable` ¶

tasks `property` `writable` ¶

version `property` ¶