LoggingMiddleware

Complexity

Total Complexity

8

Size/Duplication

Total Lines	69
Duplicated Lines	0 %

Importance

Changes	1
Bugs	0	Features	0

3 Methods

Rating	Name	Duplication	Size	Complexity
C	__call__()	0	60	7
A	__init__()	0	3	1
A	custom_start_response()	0	9	3

# Licensed to the StackStorm, Inc ('StackStorm') under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import time
import types

from st2common.constants.api import REQUEST_ID_HEADER
from st2common import log as logging
from st2common.router import Request

LOG = logging.getLogger(__name__)

try:
    clock = time.perf_counter
except AttributeError:
    clock = time.time


class LoggingMiddleware(object):
    """
    Logs all incoming requests and outgoing responses
    """

    def __init__(self, app, router):
        self.app = app
        self.router = router

    def __call__(self, environ, start_response):
        start_time = clock()
        status_code = []
        content_length = []

        request = Request(environ)

        # Log the incoming request
        values = {
            'method': request.method,
            'path': request.path,
            'remote_addr': request.remote_addr,
            'query': request.GET.dict_of_lists(),
            'request_id': request.headers.get(REQUEST_ID_HEADER, None)
        }

        LOG.info('%(request_id)s - %(method)s %(path)s with query=%(query)s' %

Specify string format arguments as logging function parameters

                 values, extra=values)

        def custom_start_response(status, headers, exc_info=None):
            status_code.append(int(status.split(' ')[0]))

            for name, value in headers:
                if name.lower() == 'content-length':
                    content_length.append(int(value))
                    break

            return start_response(status, headers, exc_info)

        retval = self.app(environ, custom_start_response)

        endpoint, path_vars = self.router.match(request)

        log_result = endpoint.get('x-log-result', True)

        if isinstance(retval, types.GeneratorType):
            content_length = [float('inf')]
            log_result = False

        # Log the incoming request
        values = {
            'method': request.method,
            'path': request.path,
            'remote_addr': request.remote_addr,
            'status': status_code[0],
            'runtime': float("{0:.3f}".format((clock() - start_time) * 10**3)),
            'content_length': content_length[0] if content_length else len(b''.join(retval)),
            'request_id': request.headers.get(REQUEST_ID_HEADER, None)
        }

        if log_result:
            values['result'] = retval[0]
            log_msg = '%(request_id)s - %(status)s %(content_length)s %(runtime)sms\n%(result)s'\
                      % values
        else:
            log_msg = '%(request_id)s - %(status)s %(content_length)s %(runtime)sms' % values

        LOG.info(log_msg, extra=values)

        return retval