can callbacks be implemented with the new @task decorator in airflow

Airflow provides examples of task callbacks for success and failures of a task. It gives an example with an EmptyOperator as such:

import datetime
import pendulum

from airflow import DAG
from airflow.operators.empty import EmptyOperator


def task_failure_alert(context):
    print(f"Task has failed, task_instance_key_str: {context['task_instance_key_str']}")


def dag_success_alert(context):
    print(f"DAG has succeeded, run_id: {context['run_id']}")


with DAG(
    dag_id="example_callback",
    schedule=None,
    start_date=pendulum.datetime(2021, 1, 1, tz="UTC"),
    dagrun_timeout=datetime.timedelta(minutes=60),
    catchup=False,
    on_success_callback=None,
    on_failure_callback=task_failure_alert,
    tags=["example"],
):

    task1 = EmptyOperator(task_id="task1")
    task2 = EmptyOperator(task_id="task2")
    task3 = EmptyOperator(task_id="task3", on_success_callback=[dag_success_alert])
    task1 >> task2 >> task3

My question can I use these callbacks with taskflow API on the new airflow 2.0 .

Something like:

@task(task_id="some_task",on_success_callback="this_func")
def this_func(context):
    print 'the function succeeed'

Yes you can, you need to define the function "this_func" and call it (no as string). also you can not call the task function and the callback with the same name.

def this_func(context):
    ...

@task(on_success_callback=this_func)
def some_task():
    ...