RetryAbleTask Class

A Task representing with_retry scenarios.

It inherits from WhenAllTask because retryable scenarios are Tasks with equivalent to WhenAll Tasks with dynamically increasing lists of children. At every failure, we add a Timer child and a Task child to the list of pending tasks.

Constructor

RetryAbleTask(child: TaskBase, retry_options: RetryOptions, context)

Parameters

Name	Description
child Required
retry_options Required
context Required

Methods

change_state	Transition a running Task to a terminal state: success or failure.
handle_completion	Manage sub-task completion events.
propagate	Notify parent Task of this Task's state change.
set_is_played	Set the is_played flag for the Task. Needed for updating the orchestrator's is_replaying flag.
set_value	Set the value of this Task: either an exception of a result.
try_set_value	Transition a Retryable Task to a terminal state and set its value.

change_state

Transition a running Task to a terminal state: success or failure.

change_state(state: TaskState)

Parameters

Name	Description
state Required	TaskState The terminal state to assign to this Task

Exceptions

Type	Description
Exception	When the input state is RUNNING

handle_completion

Manage sub-task completion events.

handle_completion(child: TaskBase)

Parameters

Name	Description
child Required	TaskBase The sub-task that completed

Exceptions

Type	Description
Exception	When the calling sub-task was not registered with this Task's pending sub-tasks.

propagate

Notify parent Task of this Task's state change.

propagate()

set_is_played

Set the is_played flag for the Task.

Needed for updating the orchestrator's is_replaying flag.

set_is_played(is_played: bool)

Parameters

Name	Description
is_played Required	bool Whether the latest event for this Task has been played before.

set_value

Set the value of this Task: either an exception of a result.

set_value(is_error: bool, value: Any)

Parameters

Name	Description
is_error Required	bool Whether the value represents an exception of a result.
value Required	Any The value of this Task

Exceptions

Type	Description
Exception	When the Task failed but its value was not an Exception

try_set_value

Transition a Retryable Task to a terminal state and set its value.

try_set_value(child: TaskBase)

Parameters

Name	Description
child Required	TaskBase A sub-task that just completed

Attributes

id_

Obtain the task's ID.

Since this is an internal-only abstraction, the task ID is represented by the ID of its inner/wrapped task plus a suffix: "_retryable_proxy"

Returns

Type	Description
[type]	[description]

is_completed

Get indicator of whether the task completed.

Note that completion is not equivalent to success.