for循环中的错误/异常处理-python

时间:2018-07-05 20:32:43

标签: python for-loop error-handling exception-handling google-cloud-nl

我正在使用Google Cloud NL API来分析某些描述的观点。对于某些行,错误InvalidArgument: 400 The language vi is not supported for document_sentiment analysis.不断弹出,我想围绕它建立一个方法,而不是拼命尝试找出发生这种情况的原因并清除负责的行。不幸的是,我是Python的新手,不确定如何正确地做它。

我的代码如下:

description_list = []
sentimentscore_list=[]
magnitude_list=[]

# Create a Language client
language_client = google.cloud.language.LanguageServiceClient()


for i in range(len(description)):      # use the translated description if the original description is not in English
    if description_trans[i] == '':
        descr = description[i]
    else:
        descr = description_trans[i]


    document = google.cloud.language.types.Document(
        content=descr,
        type=google.cloud.language.enums.Document.Type.PLAIN_TEXT)

    # Use Language to detect the sentiment of the text.
    response = language_client.analyze_sentiment(document=document)
    sentiment = response.document_sentiment
    sentimentscore_list.append(sentiment.score)
    magnitude_list.append(sentiment.magnitude)
    # Add the description that was actually used to the description list
    description_list.append(descr)

任何人都可以向我解释如何将for循环(或后者的后半部分)包装到错误/异常处理中,以使其仅“跳过”无法读取的内容并继续执行。下一个?另外,我希望仅在实际分析描述时才添加“ description_list”(而不是在错误处理中被卡住)。

我们非常感谢您的帮助!!谢谢:)


编辑:有人要求我提供更完整的错误回溯:

回溯(最近通话最近一次):

  File "<ipython-input-64-6e3db1d976c9>", line 1, in <module>
    runfile('/Users/repos/NLPAnalysis/GoogleTest.py', wdir='/Users/repos/NLPAnalysis')

  File "/Users/anaconda3/lib/python3.6/site-packages/spyder/utils/site/sitecustomize.py", line 710, in runfile
    execfile(filename, namespace)

  File "/Users/anaconda3/lib/python3.6/site-packages/spyder/utils/site/sitecustomize.py", line 101, in execfile
    exec(compile(f.read(), filename, 'exec'), namespace)

  File "/Users/repos/NLPAnalysis/GoogleTest.py", line 45, in <module>
    response = language_client.analyze_sentiment(document=document)

  File "/Users/anaconda3/lib/python3.6/site-packages/google/cloud/language_v1/gapic/language_service_client.py", line 180, in analyze_sentiment
    return self._analyze_sentiment(request, retry=retry, timeout=timeout)

  File "/Users/anaconda3/lib/python3.6/site-packages/google/api_core/gapic_v1/method.py", line 139, in __call__
    return wrapped_func(*args, **kwargs)

  File "/Users/anaconda3/lib/python3.6/site-packages/google/api_core/retry.py", line 260, in retry_wrapped_func
    on_error=on_error,

  File "/Users/anaconda3/lib/python3.6/site-packages/google/api_core/retry.py", line 177, in retry_target
    return target()

  File "/Users/anaconda3/lib/python3.6/site-packages/google/api_core/timeout.py", line 206, in func_with_timeout
    return func(*args, **kwargs)

  File "/Users/anaconda3/lib/python3.6/site-packages/google/api_core/grpc_helpers.py", line 56, in error_remapped_callable
    six.raise_from(exceptions.from_grpc_error(exc), exc)

  File "<string>", line 3, in raise_from

InvalidArgument: 400 The language vi is not supported for document_sentiment analysis.

2 个答案:

答案 0 :(得分:1)

在回溯中,查看第四行,它与代码中的同一行并引起异常。除了在我们认为会引起异常的代码块之外,我们总是尝试一下。其他所有内容都放在块外。

try:
    response = language_client.analyze_sentiment(document=document)
except InvalidArgument:
    continue
# Assuming none of these would work if we don't get response?
description_list.append(descr)
sentiment = response.document_sentiment
entimentscore_list.append(sentiment.score)
magnitude_list.append(sentiment.magnitude)
# Add the description that was actually used to the description list

我们尝试以获取语言客户端的响应,这引发了一个异常,提示 InvalidArgument ,我们抓住了。现在我们知道我们不需要做任何事情,我们使用 continue 继续进行下一个迭代。

您可能需要导入InvalidArgument,例如-

from google.api_core.exceptions import InvalidArgument

在代码中使用它之前。

您对继续是正确的。有关continue statementhow to handle exceptions in python的更多信息。

答案 1 :(得分:1)

我同意ThatBird的观点,即在try-block中包装太多代码会使调试内部错误变得复杂。我建议使用python的 continue 关键字。

try:
    # smallest block of code you foresee an error in
    response = language_client.analyze_sentiment(document=document) # I think your exception is being raised in this call
except InvalidArgument as e:
    # your trace shows InvalidArgument being raised and it appears you dont care about it
    continue # continue to next iteration since this error is expected
except SomeOtherOkayException as e:
    # this is an example exception that is also OK and "skippable"
    continue # continue to next iteration
except Exception as e:
    # all other exceptions are BAD and unexpected.This is a larger problem than just this loop
    raise e # break the looping and raise to calling function

sentiment = response.document_sentiment
sentimentscore_list.append(sentiment.score)
magnitude_list.append(sentiment.magnitude)
# Add the description that was actually used to the description list
description_list.append(descr)
# more code here...

从本质上讲,您正在明确地捕获预期的异常,并在发生异常时将其丢弃并继续进行下一个异常。您应该提出所有其他异常。