#
# Fluentd
#
#    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.
#

# The following Fluentd parser plugin, aims to simplify the parsing of multiline
# logs found in Kubernetes nodes. Since many log files shared the same format and
# in order to simplify the configuration, this plugin provides a 'kubernetes' format
# parser (built on top of MultilineParser).
#
# When tailing files, this 'kubernetes' format should be applied to the following
# log file sources:
#
#  - /var/log/kubelet.log
#  - /var/log/kube-proxy.log
#  - /var/log/kube-apiserver.log
#  - /var/log/kube-controller-manager.log
#  - /var/log/kube-scheduler.log
#  - /var/log/rescheduler.log
#  - /var/log/glbc.log
#  - /var/log/cluster-autoscaler.log
#
# Usage:
#
# ---- fluentd.conf ----
#
# <source>
#    type tail
#    format kubernetes
#    path ./kubelet.log
#    read_from_head yes
#    tag kubelet
# </source>
#
# ----   EOF       ---

require 'fluent/parser'

module Fluent
  class KubernetesParser < Fluent::TextParser::MultilineParser
    Fluent::Plugin.register_parser("kubernetes", self)

    CONF_FORMAT_FIRSTLINE = %q{/^\w\d{4}/}
    CONF_FORMAT1 = %q{/^(?<severity>\w)(?<time>\d{4} [^\s]*)\s+(?<pid>\d+)\s+(?<source>[^ \]]+)\] (?<message>.*)/}
    CONF_TIME_FORMAT = "%m%d %H:%M:%S.%N"

    def configure(conf)
      conf['format_firstline'] = CONF_FORMAT_FIRSTLINE
      conf['format1'] = CONF_FORMAT1
      conf['time_format'] = CONF_TIME_FORMAT
      super
    end
  end
end
