ValueError: preexec_fn is not supported on Windows platforms

[quoctienkt]

Apache Airflow version

2.5.1

What happened

I'm following Airflow tutorial, and I faced error when come to this doc:
Tutorials - Testing section

This is error stack trace:

D:\Documents\Projects\Learning\Airflow>airflow tasks test tutorial sleep 2015-06-01
c:\users\quoct\appdata\local\programs\python\python38\lib\site-packages\airflow\models\base.py:49 MovedIn20Warning: [31mDeprecated API features detected! These feature(s) are not compatible with SQLAlchemy 2.0. [32mTo prevent incompatible upgrades prior to updating applications, ensure requirements files are pinned to "sqlalchemy<2.0". [36mSet environment variable SQLALCHEMY_WARN_20=1 to show all deprecation warnings.  Set environment variable SQLALCHEMY_SILENCE_UBER_WARNING=1 to silence this message.[0m (Background on SQLAlchemy 2.0 at: 
https://sqlalche.me/e/b8d9)
[2023-02-25 21:16:09,229] {dagbag.py:538} INFO - Filling up the DagBag from C:\Users\quoct\airflow\dags
[2023-02-25 21:16:09,644] {taskmixin.py:205} WARNING - Dependency <Task(BashOperator): create_entry_group>, delete_entry_group already registered for DAG: example_complex
[2023-02-25 21:16:09,645] {taskmixin.py:205} WARNING - Dependency <Task(BashOperator): delete_entry_group>, create_entry_group already registered for DAG: example_complex
[2023-02-25 21:16:09,646] {taskmixin.py:205} WARNING - Dependency <Task(BashOperator): create_entry_gcs>, delete_entry already registered for DAG: example_complex
[2023-02-25 21:16:09,646] {taskmixin.py:205} WARNING - Dependency <Task(BashOperator): delete_entry>, create_entry_gcs already registered for DAG: example_complex
[2023-02-25 21:16:09,647] {taskmixin.py:205} WARNING - Dependency <Task(BashOperator): create_tag>, delete_tag already registered for DAG: example_complex
[2023-02-25 21:16:09,648] {taskmixin.py:205} WARNING - Dependency <Task(BashOperator): delete_tag>, create_tag already registered for DAG: example_complex
[2023-02-25 21:16:09,818] {taskmixin.py:205} WARNING - Dependency <Task(_PythonDecoratedOperator): prepare_email>, send_email already registered for DAG: example_dag_decorator
[2023-02-25 21:16:09,819] {taskmixin.py:205} WARNING - Dependency <Task(EmailOperator): send_email>, prepare_email already registered for DAG: example_dag_decorator
[2023-02-25 21:16:09,893] {taskmixin.py:205} WARNING - Dependency <Task(_PythonDecoratedOperator): print_the_context>, log_sql_query already registered for DAG: example_python_operator
[2023-02-25 21:16:09,894] {taskmixin.py:205} WARNING - Dependency <Task(_PythonDecoratedOperator): log_sql_query>, print_the_context already registered for DAG: example_python_operator
[2023-02-25 21:16:09,896] {taskmixin.py:205} WARNING - Dependency <Task(_PythonDecoratedOperator): print_the_context>, log_sql_query already registered for DAG: example_python_operator
[2023-02-25 21:16:09,897] {taskmixin.py:205} WARNING - Dependency <Task(_PythonDecoratedOperator): log_sql_query>, print_the_context already registered for DAG: example_python_operator
[2023-02-25 21:16:09,899] {taskmixin.py:205} WARNING - Dependency <Task(_PythonDecoratedOperator): print_the_context>, log_sql_query already registered for DAG: example_python_operator
[2023-02-25 21:16:09,900] {taskmixin.py:205} WARNING - Dependency <Task(_PythonDecoratedOperator): log_sql_query>, print_the_context already registered for DAG: example_python_operator
[2023-02-25 21:16:09,901] {taskmixin.py:205} WARNING - Dependency <Task(_PythonDecoratedOperator): print_the_context>, log_sql_query already registered for DAG: example_python_operator
[2023-02-25 21:16:09,902] {taskmixin.py:205} WARNING - Dependency <Task(_PythonDecoratedOperator): log_sql_query>, print_the_context already registered for DAG: example_python_operator
c:\users\quoct\appdata\local\programs\python\python38\lib\site-packages\airflow\cli\commands\task_command.py:159 RemovedInAirflow3Warning: Calling `DAG.create_dagrun()` without an explicit data interval is deprecated
[2023-02-25 21:16:10,813] {taskinstance.py:1083} INFO - Dependencies all met for <TaskInstance: tutorial.sleep __airflow_temporary_run_2023-02-25T14:16:10.736460+00:00__ [None]>
[2023-02-25 21:16:10,821] {taskinstance.py:1083} INFO - Dependencies all met for <TaskInstance: tutorial.sleep __airflow_temporary_run_2023-02-25T14:16:10.736460+00:00__ [None]>
[2023-02-25 21:16:10,822] {taskinstance.py:1279} INFO -
--------------------------------------------------------------------------------
[2023-02-25 21:16:10,822] {taskinstance.py:1280} INFO - Starting attempt 1 of 4
[2023-02-25 21:16:10,823] {taskinstance.py:1281} INFO -
--------------------------------------------------------------------------------
[2023-02-25 21:16:10,824] {taskinstance.py:1300} INFO - Executing <Task(BashOperator): sleep> on 2015-06-01T00:00:00+00:00
[2023-02-25 21:16:10,984] {taskinstance.py:1507} INFO - Exporting the following env vars:
AIRFLOW_CTX_DAG_EMAIL=airflow@example.com
AIRFLOW_CTX_DAG_OWNER=airflow
AIRFLOW_CTX_DAG_ID=tutorial
AIRFLOW_CTX_TASK_ID=sleep
AIRFLOW_CTX_EXECUTION_DATE=2015-06-01T00:00:00+00:00
AIRFLOW_CTX_TRY_NUMBER=1
AIRFLOW_CTX_DAG_RUN_ID=__airflow_temporary_run_2023-02-25T14:16:10.736460+00:00__
[2023-02-25 21:16:11,004] {subprocess.py:63} INFO - Tmp dir root location: 
 C:\Users\quoct\AppData\Local\Temp
[2023-02-25 21:16:11,006] {subprocess.py:75} INFO - Running command: ['bash', '-c', 'sleep 5']
[2023-02-25 21:16:11,007] {taskinstance.py:1768} ERROR - Task failed with exception
Traceback (most recent call last):
  File "c:\users\quoct\appdata\local\programs\python\python38\lib\site-packages\airflow\operators\bash.py", line 187, in execute        
    result = self.subprocess_hook.run_command(
  File "c:\users\quoct\appdata\local\programs\python\python38\lib\site-packages\airflow\hooks\subprocess.py", line 77, in run_command   
    self.sub_process = Popen(
  File "c:\users\quoct\appdata\local\programs\python\python38\lib\subprocess.py", line 761, in __init__
    raise ValueError("preexec_fn is not supported on Windows "
ValueError: preexec_fn is not supported on Windows platforms

What you think should happen instead

No response

How to reproduce

Create a python file with below code:

from datetime import datetime, timedelta
from textwrap import dedent

# The DAG object; we'll need this to instantiate a DAG
from airflow import DAG

# Operators; we need this to operate!
from airflow.operators.bash import BashOperator

import subprocess
subprocess.call('preexec_fn', shell=True)

with DAG(
    "tutorial",
    # These args will get passed on to each operator
    # You can override them on a per-task basis during operator initialization
    default_args={
        "depends_on_past": False,
        "email": ["tutorial@test.com"],
        "email_on_failure": False,
        "email_on_retry": False,
        "retries": 1,
        "retry_delay": timedelta(minutes=5),
        # 'queue': 'bash_queue',
        # 'pool': 'backfill',
        # 'priority_weight': 10,
        # 'end_date': datetime(2016, 1, 1),
        # 'wait_for_downstream': False,
        # 'sla': timedelta(hours=2),
        # 'execution_timeout': timedelta(seconds=300),
        # 'on_failure_callback': some_function,
        # 'on_success_callback': some_other_function,
        # 'on_retry_callback': another_function,
        # 'sla_miss_callback': yet_another_function,
        # 'trigger_rule': 'all_success'
    },
    description="A simple tutorial DAG",
    schedule=timedelta(days=1),
    start_date=datetime(2021, 1, 1),
    catchup=False,
    tags=["example"],
) as dag:

    # t1, t2 and t3 are examples of tasks created by instantiating operators
    t1 = BashOperator(
        task_id="print_date",
        bash_command="date",
    )

    t2 = BashOperator(
        task_id="sleep",
        depends_on_past=False,
        bash_command="sleep 5",
        retries=3,
    )
    t1.doc_md = dedent(
        """\
    #### Task Documentation
    You can document your task using the attributes `doc_md` (markdown),
    `doc` (plain text), `doc_rst`, `doc_json`, `doc_yaml` which gets
    rendered in the UI's Task Instance Details page.
    ![img](http://montcs.bloomu.edu/~bobmon/Semesters/2012-01/491/import%20soul.png)
    **Image Credit:** Randall Munroe, [XKCD](https://xkcd.com/license.html)
    """
    )

    dag.doc_md = __doc__  # providing that you have a docstring at the beginning of the DAG; OR
    dag.doc_md = """
    This is a documentation placed anywhere
    """  # otherwise, type it like this
    templated_command = dedent(
        """
    {% for i in range(5) %}
        echo "{{ ds }}"
        echo "{{ macros.ds_add(ds, 7)}}"
    {% endfor %}
    """
    )

    t3 = BashOperator(
        task_id="templated",
        depends_on_past=False,
        bash_command=templated_command,
    )

    t1 >> [t2, t3]

Then run

# initialize the database tables
airflow db init

# print the list of active DAGs
airflow dags list

# prints the list of tasks in the "tutorial" DAG
airflow tasks list tutorial

# prints the hierarchy of tasks in the "tutorial" DAG
airflow tasks list tutorial --tree

# command layout: command subcommand [dag_id] [task_id] [(optional) date]

# testing print_date
airflow tasks test tutorial print_date 2015-06-01

# testing sleep
airflow tasks test tutorial sleep 2015-06-01

Operating System

Window 10 21H2 19044.2604

Versions of Apache Airflow Providers

No response

Deployment

Other

Deployment details

No response

Anything else

No response

Are you willing to submit PR?

• Yes I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct

[boring-cyborg]

Thanks for opening your first issue here! Be sure to follow the issue template!

[potiuk]

Correct. Airflow does not work on windows natively (this is documented in our prerequisites) - see note at https://airflow.apache.org/docs/apache-airflow/stable/installation/prerequisites.html . The issue that thracks it is #10388 - for now you need to use WSL2 if you want to run airflow on Windows.

[quoctienkt]

@potiuk
Thanks for quick response!