A Step represents a user-defined step, that is, a method annotated with the @step decorator.
It contains Task objects associated with the step, that is, all executions of the step. The step may contain multiple Tasks in the case of a foreach step.
Constructor
Step(pathspec: Optional[str] = None,
attempt: Optional[int] = None)
Parameters
Path to the step (e.g., ‘FlowName/RunID/StepName’).
Specific attempt number (only applicable to Task or DataArtifact).
Properties
The step ID (step name).
Returns a Task object belonging to this step.
This is useful when the step only contains one task (a linear step for example).
Returns: A task in the step or None.
finished_at
finished_at: Optional[datetime]
environment_info
environment_info: Optional[Dict[str, Any]]
parent_steps
parent_steps: Iterator[Step]
Step objects.
child_steps
child_steps: Iterator[Step]
Step objects.
Tags associated with the run this object belongs to (user and system tags).
user_tags: FrozenSet[str]
system_tags: FrozenSet[str]
created_at
Date and time this object was first created.
parent: Optional[MetaflowObject]
pathspec
Pathspec of this object (e.g., ‘FlowName/RunID/StepName’).
path_components
path_components: List[str]
origin_pathspec
origin_pathspec: Optional[str]
Methods
tasks()
tasks(*tags: str) -> Iterable[Task]
Task objects in the step. This is an alias to iterating the object itself.
Parameters:
tags (str): No op (legacy functionality)
Yields: Task objects in this step.
control_task
control_task: Optional[Task]
control_tasks()
control_tasks(*tags: str) -> Iterator[Task]
tags (str): Tags to match
Yields: Control Task objects for this step.
__iter__()
__iter__() -> Iterator[Task]
Task of this Step.
Yields: Task objects in this Step.
__getitem__()
__getitem__(task_id: str) -> Task
Task object with the task ID ‘task_id’.
Parameters:
Returns: Task for this task ID in this Step.
Raises: KeyError if the task_id does not identify a valid Task object.
__contains__()
__contains__(id: str) -> bool
id (str): Name of the child object
Returns: True if the child exists or False otherwise.
is_in_namespace()
is_in_namespace() -> bool
Usage Examples
Access a single task
from metaflow import Step
step = Step('MyFlow/123/start')
task = step.task
if task:
print(f"Task ID: {task.id}")
print(f"Task finished: {task.finished}")
print(f"Task data: {task.data}")
Iterate over all tasks in a foreach
from metaflow import Step
step = Step('MyFlow/123/process')
for task in step:
print(f"Task {task.id}:")
print(f" Index: {task.index}")
print(f" Successful: {task.successful}")
Access specific task
from metaflow import Step
step = Step('MyFlow/123/process')
task = step['42']
print(f"Task data: {task.data.result}")
Check step completion
from metaflow import Step
step = Step('MyFlow/123/train')
if step.finished_at:
print(f"Step finished at: {step.finished_at}")
else:
print("Step is still running")
Navigate step graph
from metaflow import Step
step = Step('MyFlow/123/process')
print("Parent steps:")
for parent in step.parent_steps:
print(f" {parent.id}")
print("Child steps:")
for child in step.child_steps:
print(f" {child.id}")
Access environment info
from metaflow import Step
step = Step('MyFlow/123/train')
if step.environment_info:
print(f"Environment: {step.environment_info}")
