**Description**

I have noticed that the stable REST API doesn't have the ability to run a task (which is possible from the airflow web interface.
I think it would be nice to have either:
- Run task 
- Run all failing tasks (rerun from point of failure)
this ability for integrations.

**Use case / motivation**

I would like the ability to identify the failing tasks on a specific DAG Run and rerun only them.
I would like to do it remotely (non-interactive) using the REST API.
I could write a script that run only the failing tasks, but I couldn't find a way to "Run" a task, when I have the task instance ID.

**Are you willing to submit a PR?**

Not at this stage

**Related Issues**



airflow/api_connexion/schemas/task_instance_schema.py
"""Schema for the task instance reference schema"""
    task_id = fields.Str()
    dag_run_id = fields.Str()
    dag_id = fields.Str()
    execution_date = fields.DateTime()
    def get_attribute(self, obj, attr, default):
        """Overwritten marshmallow function"""
        task_instance_attr = ['task_id', 'execution_date', 'dag_id']
        if attr in task_instance_attr:
            obj = obj[0]  
            return get_value(obj, attr, default)
        return obj[1]
class TaskInstanceReferenceCollection(NamedTuple):
    """List of objects with metadata about taskinstance and dag_run_id"""
    task_instances: List[Tuple[TaskInstance, str]]
class TaskInstanceReferenceCollectionSchema(Schema):
    """Collection schema for task reference"""
    task_instances = fields.List(fields.Nested(TaskInstanceReferenceSchema))
task_instance_schema = TaskInstanceSchema()
task_instance_collection_schema = TaskInstanceCollectionSchema()
task_instance_batch_form = TaskInstanceBatchFormSchema()
clear_task_instance_form = ClearTaskInstanceFormSchema()
set_task_instance_state_form = SetTaskInstanceStateFormSchema()
task_instance_reference_schema = TaskInstanceReferenceSchema()
task_instance_reference_collection_schema = TaskInstanceReferenceCollectionSchema()