Python记录到StringIO处理程序

Question

我有一个python测试,我想测试日志记录是否正常工作.例如,我有一个创建用户的函数,最后日志记录将响应写入日志文件.

logger = logging.getLogger('mylogger')
logger.setLevel(logging.DEBUG)
handler = logging.handlers.WatchedFileHandler('mylogfile.log')
formatter = logging.Formatter('%(asctime)s: %(message)s',
                              '%d/%b/%Y:%H:%M:%S %z')
handler.setFormatter(formatter)
logger.addHandler(handler)
logger.info('Some log text')

在我的测试用例中,我想将日志输出发送到StringIO.

class MyTest(unittest.TestCase):
    def setUp(self):
        stream = StringIO()
        self.handler = logging.StreamHandler(stream)
        log = logging.getLogger('mylogger')
        log.removeHandler(log.handlers[0])
        log.addHandler(self.handler)

    def tearDown(self):
        log = logging.getLogger('mylogger')
        log.removeHandler(self.handler)
        self.handler.close()

问题是,我不确定我应该如何测试我的记录器是否正常工作.

Answer 1

这是一个有效的示例,请确保设置日志级别,并刷新缓冲区.

class MyTest(unittest.TestCase):
    def setUp(self):
        self.stream = StringIO()
        self.handler = logging.StreamHandler(self.stream)
        self.log = logging.getLogger('mylogger')
        self.log.setLevel(logging.INFO)
        for handler in self.log.handlers: 
            self.log.removeHandler(handler)
        self.log.addHandler(self.handler)
    def testLog(self):
        self.log.info("test")
        self.handler.flush()
        print '[', self.stream.getvalue(), ']'
        self.assertEqual(self.stream.getvalue(), 'test')

    def tearDown(self):
        self.log.removeHandler(self.handler)
        self.handler.close()

if __name__=='__main__':
    unittest.main()

进一步阅读,这里是一个Temporily捕获Python日志记录到字符串缓冲区的示例,它显示了如何进行格式化.