preparing to split chameleon out of voltha
this is a prep step to make chameleon independent
of voltha. Chameleon will move out of voltha but
repo will drop chameleon in the same place as it
currently is. This means that voltha's build process
will not change and the code changes to chameleon
will automatically be applied to the correct repo.
Change-Id: I754d6b5b28ea99333b19140d6c1a94e8198f9d3a
diff --git a/utils/structlog_setup.py b/utils/structlog_setup.py
new file mode 100644
index 0000000..6a149c0
--- /dev/null
+++ b/utils/structlog_setup.py
@@ -0,0 +1,113 @@
+#
+# Copyright 2017 the original author or authors.
+#
+# Licensed 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.
+#
+
+"""Setting up proper logging for Voltha"""
+
+import logging
+import logging.config
+from collections import OrderedDict
+
+import structlog
+from structlog.stdlib import BoundLogger, INFO
+
+try:
+ from thread import get_ident as _get_ident
+except ImportError:
+ from dummy_thread import get_ident as _get_ident
+
+
+class FluentRenderer(object):
+ def __call__(self, logger, name, event_dict):
+ # in order to keep structured log data in event_dict to be forwarded as
+ # is to the fluent logger, we need to pass it into the logger framework
+ # as the first positional argument.
+ args = (event_dict, )
+ kwargs = {}
+ return args, kwargs
+
+
+class PlainRenderedOrderedDict(OrderedDict):
+ """Our special version of OrderedDict that renders into string as a dict,
+ to make the log stream output cleaner.
+ """
+ def __repr__(self, _repr_running={}):
+ 'od.__repr__() <==> repr(od)'
+ call_key = id(self), _get_ident()
+ if call_key in _repr_running:
+ return '...'
+ _repr_running[call_key] = 1
+ try:
+ if not self:
+ return '{}'
+ return '{%s}' % ", ".join("%s: %s" % (k, v)
+ for k, v in self.items())
+ finally:
+ del _repr_running[call_key]
+
+
+def setup_logging(log_config, instance_id, verbosity_adjust=0, fluentd=None):
+ """
+ Set up logging such that:
+ - The primary logging entry method is structlog
+ (see http://structlog.readthedocs.io/en/stable/index.html)
+ - By default, the logging backend is Python standard lib logger
+ - Alternatively, fluentd can be configured with to be the backend,
+ providing direct bridge to a fluent logging agent.
+ """
+
+ def add_exc_info_flag_for_exception(_, name, event_dict):
+ if name == 'exception':
+ event_dict['exc_info'] = True
+ return event_dict
+
+ def add_instance_id(_, __, event_dict):
+ event_dict['instance_id'] = instance_id
+ return event_dict
+
+ # if fluentd is specified, we need to override the config data with
+ # its host and port info
+ if fluentd is not None:
+ fluentd_host = fluentd.split(':')[0].strip()
+ fluentd_port = int(fluentd.split(':')[1].strip())
+
+ handlers = log_config.get('handlers', None)
+ if isinstance(handlers, dict):
+ for _, defs in handlers.iteritems():
+ if isinstance(defs, dict):
+ if defs.get('class', '').endswith('FluentHandler'):
+ defs['host'] = fluentd_host
+ defs['port'] = fluentd_port
+
+ # Configure standard logging
+ logging.config.dictConfig(log_config)
+ logging.root.level -= 10 * verbosity_adjust
+
+ processors = [
+ add_exc_info_flag_for_exception,
+ structlog.processors.StackInfoRenderer(),
+ structlog.processors.format_exc_info,
+ add_instance_id,
+ FluentRenderer(),
+ ]
+ structlog.configure(logger_factory=structlog.stdlib.LoggerFactory(),
+ context_class=PlainRenderedOrderedDict,
+ wrapper_class=BoundLogger,
+ processors=processors)
+
+ # Mark first line of log
+ log = structlog.get_logger()
+ log.info("first-line")
+ return log