log middleware

log_middleware.py

# duration: api 耗时，按秒计
# duration_ms: api 耗时，按毫秒计
# level: api 耗时档次，分为
#        LEVEL-A: x < 1 sec
#        LEVEL-B: 1 sec < x < 5 sec
#        LEVEL-C: 5 sec < x < 10 sec
#        LEVEL-D: x > 10 sec
# method: http 请求方法
# status_code: 请求响应状态
# user_agent: HTTP_USER_AGENT
DURATION_LOG_FORMATTER = ('{level} {x_forwarded_for} {user_agent} {method}'
                          ' {path} {status_code} {duration}')
class DurationMiddleware(object):
    def process_request(self, request):
        request.duration_start = time.time()

    def process_response(self, request, response):
        duration = time.time() - request.duration_start
        if duration < 1:
            level = 'LEVEL-A'
        elif duration < 5:
            level = 'LEVEL-B'
        elif duration < 10:
            level = 'LEVEL-C'
        else:
            level = 'LEVEL-D'

        info = {'x_user_real_ip': request.META.get('HTTP_X_USER_REAL_IP', '-'),
                'remote_addr': request.META.get('REMOTE_ADDR', '-'),
                'x_forwarded_for': request.META.get('HTTP_X_FORWARDED_FOR',
                                                    '-'),
                'user_agent':  request.META.get('HTTP_USER_AGENT', '-'),
                'path': request.path.encode('utf8'),
                'duration': str(decimal.Decimal(duration).quantize(
                    decimal.Decimal('0.001'))),
                'duration_ms': str(decimal.Decimal(duration * 1000).quantize(
                    decimal.Decimal('1'))),
                'level': level,
                'method': request.method,
                'status_code': getattr(response, 'status_code', '-')}
        try:
            msg = settings.DURATION_LOG_FORMATTER.format(**info)
            if 'messenger' in request.path or level != 'LEVEL-A':
                logging.info(msg)
        except Exception:
            logging.error(
                'illegal format in settings.DURATION_LOG_FORMATTER, info: %s',
                info, exc_info=True)
        del request.duration_start
        return response