无法设置气流，“启动气流数据库”时出错答案

【问题标题】：Not able to setup airflow, getting error while "Initiating Airflow Database"无法设置气流，“启动气流数据库”时出错
【发布时间】：2020-04-07 04:42:54
【问题描述】：

无法设置气流，“启动气流数据库”时出错。我收到以下错误：

  File "/Library/Frameworks/Python.framework/Versions/3.8/bin/airflow", line 26, in <module>
    from airflow.bin.cli import CLIFactory
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/airflow/bin/cli.py", line 79, in <module>
    api_module = import_module(conf.get('cli', 'api_client'))  # type: Any
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/importlib/__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/airflow/api/client/local_client.py", line 24, in <module>
    from airflow.api.common.experimental import delete_dag
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/airflow/api/common/experimental/delete_dag.py", line 25, in <module>
    from airflow.models.serialized_dag import SerializedDagModel
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/airflow/models/serialized_dag.py", line 32, in <module>
    from airflow.serialization.serialized_objects import SerializedDAG
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/airflow/serialization/serialized_objects.py", line 28, in <module>
    import cattr
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/cattr/__init__.py", line 2, in <module>
    from .converters import Converter, UnstructureStrategy
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/cattr/converters.py", line 3, in <module>
    from ._compat import (
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/cattr/_compat.py", line 86, in <module>
    from typing import _Union
ImportError: cannot import name '_Union' from 'typing' (/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/typing.py)

和路径有关吗？

【问题讨论】：

标签： python installation airflow

【解决方案1】：

这是cattrs 与 Python 3.8 中的一个错误，未解决的问题：https://github.com/Tinche/cattrs/issues/46

我建议使用 Python 3.7

【讨论】：

【解决方案2】：

我已经使用 python 3.8 重新创建了这个问题，看起来已经有补丁代码准备好在新版本的气流中发布。

同时我建议将您的 python 版本降级到 3.7.x 并重新运行气流 initdb 命令。

（我已经使用 python 3.7.7 在我的沙箱中成功安装了气流）

【讨论】：