Question

我希望创建一个从API返回的所有错误的字符串。列表中可能会返回多个错误。每个错误都是一个字典，我希望访问它的字符串：

  result: {
       errors: [{
          error: 'invalid_input',
          code: 409,
          reason: 'the inputted date field does not match required format'

       },
       {
          error: 'invalid_input',
          code: 409,
          reason: 'the inputted message field does not match required format'
        }

  }

我试过的是：

return_string = ""
if errors in result:
    for error in errors:
        returned_string += " {}".format(error['reason'])

有更多的pythonic方式吗？

Answer 1

您的代码中存在多个拼写错误。但是使用 ~~list comprehension~~ 生成器表达式的Pythonic方式更多：

return_string = ""
if "errors" in result:
    return_string = " ".join(error['reason'] for error in result['errors'])

甚至在一行中：

return_string = " ".join(error['reason'] for error in result.get('errors', []))

Answer 2

result = {
       "errors": [{
          "error": 'invalid_input',
          "code": 409,
          "reason": 'the inputted date field does not match required format'

       },
       {
          "error": 'invalid_input',
          "code": 409,
          "reason": 'the inputted message field does not match required format'
        }]

  }

return_string = ""
if result.get("errors", None):
    for error in result["errors"]:
        return_string += " {}\n".format(error['reason'])
print return_string

<强>输出：

the inputted date field does not match required format
 the inputted message field does not match required format

Answer 3

您可以使用operator.itemgetter和map从您的字典列表中获取reason密钥，例如

>>> from operator import itemgetter
>>> error_list = list(map(itemgetter('reason'),r['errors']))

这将为您提供类似

的输出

>>> ['the inputted date field does not match required format', 'the inputted message field does not match required format']

接下来，您可以使用join将这些字符串连接在一起作为一条错误消息

>>> "".join(error_list)
>>> 'the inputted date field does not match required formatthe inputted message field does not match required format'

您还可以指定要分隔这两个字符串的字符

>>> " ".join(error_list) #Whitespace
>>> 'the inputted date field does not match required format the inputted message field does not match required format'

如果你喜欢单行

>>> " ".join(map(itemgetter('reason'),r['errors']))

在Python中连接字符串

3 个答案: