**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/models/dag.py
scheduler_lock = Column(Boolean)
    
    pickle_id = Column(Integer)
    
    
    
    
    fileloc = Column(String(2000))
    
    owners = Column(String(2000))
    
    description = Column(Text)
    
    default_view = Column(String(25))
    
    schedule_interval = Column(Interval)
    
    tags = relationship('DagTag', cascade='all,delete-orphan', backref=backref('dag'))
    concurrency = Column(Integer, nullable=False)
    has_task_concurrency_limits = Column(Boolean, nullable=False)
    
    next_dagrun = Column(UtcDateTime)
    
    next_dagrun_create_after = Column(UtcDateTime)
    __table_args__ = (
        Index('idx_root_dag_id', root_dag_id, unique=False),
        Index('idx_next_dagrun_create_after', next_dagrun_create_after, unique=False),
    )
    NUM_DAGS_PER_DAGRUN_QUERY = conf.getint('scheduler', 'max_dagruns_to_create_per_loop', fallback=10)
    def __init__(self, **kwargs):