单独的 RSS 提要链接

Question

我正在使用 feedparser 模块在我的程序中创建新闻提要。

雅虎！ Finance API 链接元素实际上有两个链接：Yahoo 链接和实际文章链接（外部站点/来源）。两者用星号隔开，以下为示例：

'http://us.rd.yahoo.com/finance/external/investors/rss/SIG=12shc077a/*http://www.investors.com/news/technology/click/pokemon-go-hurting-facebook-snapchat-usage/'

注意两个项目之间的星号。

我只是想知道是否有pythonic方法可以将这两者分开，并且只读取文件的第二个链接。

感谢您的宝贵时间。

这是我的相关代码：

def parse_feed(news_feed_message, rss_url):
    ''' This function parses the Yahoo! RSS API for data of the latest five articles, and writes it to the company news text file'''

    # Define the RSS feed to parse from, as the url passed in of the company the user chose
    feed = feedparser.parse(rss_url)

    # Define the file to write the news data to the company news text file
    outFile = open('C:\\Users\\nicks_000\\PycharmProjects\\untitled\\SAT\\GUI\\Text Files\\companyNews.txt', mode='w')

    # Create a list to store the news data parsed from the Yahoo! RSS
    news_data_write = []
    # Initialise a count
    count = 0
    # For the number of articles to append to the file, append the article's title, link, and published date to the news_elements list
    for count in range(10):
        news_data_write.append(feed['entries'][count].title)
        news_data_write.append(feed['entries'][count].published)
        news_data_write.append(feed['entries'][count].link)
        # Add one to the count, so that the next article is parsed
        count+=1
        # For each item in the news_elements list, convert it to a string and write it to the company news text file
        for item in news_data_write:
            item = str(item)
            outFile.write(item+'\n')
        # For each article, write a new line to the company news text file, so that each article's data is on its own line
        outFile.write('\n')
        # Clear the news_elements list so that data is not written to the file more than once
        del(news_data_write[:])
    outFile.close()

    read_news_file(news_feed_message)

Answer 1

您可以通过以下方式拆分：

link = 'http://us.rd.yahoo.com/finance/external/investors/rss/SIG=12shc077a/*http://www.investors.com/news/technology/click/pokemon-go-hurting-facebook-snapchat-usage/'

rss_link, article_link = link.split('*')

请记住，这要求链接始终包含星号，否则您将收到以下异常：

ValueError: not enough values to unpack (expected 2, got 1)

如果你只需要第二个链接，你也可以写：

_, article_link = link.split('*')

这表示您要丢弃第一个返回值。 另一种选择是：

article_link = link.split('*')[1]

关于您的代码：如果您在打开输出文件后的任何地方出现异常，它将无法正确关闭。使用 open 上下文管理器 (docs) 或 try ... finally 块 (docs) 确保无论发生什么都关闭文件。

上下文管理器：

with open('youroutputfile', 'w') as f:
    # your code
    f.write(…)

异常处理程序：

try:
    f = open('youroutputfile', 'w')
    f.write(…)
finally:
    f.close()