相关疑难解决方法(0)

Python raise和raise fromPython 之间的区别是什么？

try:
    raise ValueError
except Exception as e:
    raise IndexError

产量

Traceback (most recent call last):
  File "tmp.py", line 2, in <module>
    raise ValueError
ValueError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "tmp.py", line 4, in <module>
    raise IndexError
IndexError

和

try:
    raise ValueError
except Exception as e:
    raise IndexError from e

产量

Traceback (most recent call last):
  File "tmp.py", line 2, in <module>
    raise ValueError …

我有一个小的 python 代码，我在其中使用了异常处理。

def handler(event):
    try:
        client = boto3.client('dynamodb')
        response = client.scan(TableName=os.environ["datapipeline_table"])
        return response
    except Exception as error:
        logging.exception("GetPipelinesError: %s",json.dumps(error))
        raise GetPipelinesError(json.dumps({"httpStatus": 400, "message": "Unable to fetch Pipelines"}))

class GetPipelinesError(Exception):
    pass

pylint 警告给了我“考虑使用 'from' 关键字明确重新提高”。我很少看到其他帖子，他们使用 from 并引发错误。我做了这样的修改

except Exception as GetPipelinesError:
    logging.exception("GetPipelinesError: %s",json.dumps(GetPipelinesError))
    raise json.dumps({"httpStatus": 400, "message": "Unable to fetch Pipelines"}) from GetPipelinesError

这是正确的做法吗？