Pin Markupsafe until we are able to upgrade Flask/Jinja

[potiuk]

Markupsafe 2.1.0 breaks with error: import name 'soft_unicode' from 'markupsafe'
This should be removed when either this issue is closed:
pallets/markupsafe#284
or when we will be able to upgrade JINJA to newer version (currently limited due to Flask and
Flask Application Builder)

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[github-actions]

The PR most likely needs to run full matrix of tests because it modifies parts of the core of Airflow. However, committers might decide to merge it quickly and take the risk. If they don't merge it quickly - please rebase it to the latest main at your convenience, or amend the last commit of the PR, and push it with --force-with-lease.

[kaxil]

Yeah needs to be included in 2.2.4

[potiuk]

already did :)

[vinooganesh]

Thanks @potiuk @eladkal and @kaxil for the quick fix here! This actually does block new airflow installs, so really appreciate how quickly you two moved for this.

$ pip install apache-airflow==2.2.3 --ignore-installed 
$ airflow db init 
Traceback (most recent call last):
  File "/usr/local/bin/airflow", line 5, in <module>
    from airflow.__main__ import main
  File "/usr/local/lib/python3.8/dist-packages/airflow/__init__.py", line 34, in <module>
    from airflow import settings
  File "/usr/local/lib/python3.8/dist-packages/airflow/settings.py", line 35, in <module>
    from airflow.configuration import AIRFLOW_HOME, WEBSERVER_CONFIG, conf  # NOQA F401
  File "/usr/local/lib/python3.8/dist-packages/airflow/configuration.py", line 37, in <module>
    from airflow.exceptions import AirflowConfigException
  File "/usr/local/lib/python3.8/dist-packages/airflow/exceptions.py", line 26, in <module>
    from airflow.api_connexion.exceptions import NotFound as ApiConnextionNotFound
  File "/usr/local/lib/python3.8/dist-packages/airflow/api_connexion/exceptions.py", line 21, in <module>
    from airflow._vendor.connexion import FlaskApi, ProblemException, problem
  File "/usr/local/lib/python3.8/dist-packages/airflow/_vendor/connexion/__init__.py", line 5, in <module>
    from .apis import AbstractAPI  # NOQA
  File "/usr/local/lib/python3.8/dist-packages/airflow/_vendor/connexion/apis/__init__.py", line 1, in <module>
    from .abstract import AbstractAPI  # NOQA
  File "/usr/local/lib/python3.8/dist-packages/airflow/_vendor/connexion/apis/abstract.py", line 16, in <module>
    from ..spec import Specification
  File "/usr/local/lib/python3.8/dist-packages/airflow/_vendor/connexion/spec.py", line 5, in <module>
    import jinja2
  File "/usr/local/lib/python3.8/dist-packages/jinja2/__init__.py", line 12, in <module>
    from .environment import Environment
  File "/usr/local/lib/python3.8/dist-packages/jinja2/environment.py", line 25, in <module>
    from .defaults import BLOCK_END_STRING
  File "/usr/local/lib/python3.8/dist-packages/jinja2/defaults.py", line 3, in <module>
    from .filters import FILTERS as DEFAULT_FILTERS  # noqa: F401
  File "/usr/local/lib/python3.8/dist-packages/jinja2/filters.py", line 13, in <module>
    from markupsafe import soft_unicode
ImportError: cannot import name 'soft_unicode' from 'markupsafe' (/usr/local/lib/python3.8/dist-packages/markupsafe/__init__.py)

[eladkal]

This actually does block new airflow installs, so really appreciate how quickly you two moved for this.

It shouldn't really have any effect if you install airflow from constraint:
https://airflow.apache.org/docs/apache-airflow/stable/installation/installing-from-pypi.html#installation-tools

[vinooganesh]

Oh interesting, I wasn't aware of that method of installation. If other people find this, this seems to work for me:

pip install "apache-airflow[celery]==2.2.3" --constraint "https://raw.githubusercontent.com/apache/airflow/constraints-2.2.3/constraints-3.8.txt" --ignore-installed

Thanks!