nornir.core.task

class nornir.core.task.AggregatedResult(name: str, **kwargs: MultiResult)

Dict-like object that aggregates the results for all devices.

You can access each individual result by doing my_aggr_result["hostname_of_device"].

property failed: bool: If True at least a host failed.

property failed_hosts: dict[str, nornir.core.task.MultiResult]: Hosts that failed during the execution of the task.

raise_on_error() → None

Raise an exception if at least a task failed.

Raises:: nornir.core.exceptions.NornirExecutionError – When at least a task failed

class nornir.core.task.MultiResult(name: str)

List-like object with the results of all the subtasks for a particular device/task.

property changed: bool: If True at least a task changed the system.

property failed: bool: If True at least a task failed.

raise_on_error() → None

Raise an exception if at least a task failed.

Raises:: nornir.core.exceptions.NornirExecutionError – When at least a task failed

class nornir.core.task.Result(host: Host | None, result: Any = None, changed: bool = False, diff: str = '', failed: bool = False, exception: BaseException | None = None, severity_level: int = 20, **kwargs: Any)

Result of running individual tasks.

Parameters:

changed (bool) – True if the task is changing the system
diff (obj) – Diff between state of the system before/after running this task
result (obj) – Result of the task execution, see task’s documentation for details
host (nornir.core.inventory.Host) – Reference to the host that lead to this result
failed (bool) – Whether the execution failed or not
severity_level (logging.LEVEL) – Severity level associated to the result of the excecution
exception (Exception) – uncaught exception thrown during the exection of the task (if any)

changed

True if the task is changing the system

Type:: bool

diff

Diff between state of the system before/after running this task

Type:: obj

result

Result of the task execution, see task’s documentation for details

Type:: obj

host

Reference to the host that lead ot this result

Type:: nornir.core.inventory.Host

failed

Whether the execution failed or not

Type:: bool

severity_level

Severity level associated to the result of the excecution

Type:: logging.LEVEL

exception

uncaught exception thrown during the exection of the task (if any)

Type:: Exception

class nornir.core.task.Task(task: Callable[..., Any], nornir: Nornir, global_dry_run: bool, processors: Processors, name: str | None = None, severity_level: int = 20, parent_task: Task | None = None, **kwargs: str)

Wrapper around a function that has to be run against multiple devices.

You won’t probably have to deal with this class yourself as nornir.core.Nornir.run() will create it automatically.

Parameters:

task (callable) – function or callable we will be calling
name (string) – name of task, defaults to task.__name__
severity_level (logging.LEVEL) – Severity level associated to the task
**kwargs – Parameters that will be passed to the task

task

function or callable we will be calling

Type:: callable

name

name of task, defaults to task.__name__

Type:: string

params: Parameters that will be passed to the task.

self.results

Intermediate results

Type:: nornir.core.task.MultiResult

host

Host we are operating with. Populated right before calling the task

Type:: nornir.core.inventory.Host

nornir

Populated right before calling the task

Type:: nornir.core.Nornir

severity_level

Severity level associated to the task

Type:: logging.LEVEL

copy() → Task

Return a copy of this task with no host and no results yet.

start() records the host it ran against and the results it produced on the task object itself, so the runners hand each host its own copy rather than sharing one task across hosts.

Returns:: A task with the same callable, parameters, processors and severity level as self.
Return type:: Task

is_dry_run(override: bool | None = None) → bool

Return whether the current task is a dry run or not.

Returns:: True if the task is a dry run, False otherwise.

run(task: Callable[..., Any], **kwargs: Any) → MultiResult

Call a task from within a task.

For instance:

def grouped_tasks(task):
    task.run(my_first_task)
    task.run(my_second_task)

nornir.run(grouped_tasks)

This method will ensure the subtask is run only for the host in the current thread.

Returns:

Results of the subtask and its own subtasks

Return type:

nornir.core.task.MultiResult

Raises:

Exception – the host attribute has not been set, which happens when calling this from outside a nested task
nornir.core.exceptions.NornirSubTaskError – the subtask failed

start(host: Host) → MultiResult

Run the task for the given host.

Parameters:: host (nornir.core.inventory.Host) – Host we are operating with. Populated right before calling the task
Returns:: Results of the task and its subtasks
Return type:: nornir.core.task.MultiResult