Fix Swift logging

Swift uses Syslog, but it uses a custom log format.  So this commit
adds a specific Heka decoder for Swift.

It also increases the log level from "warning" to "info" to make
Swift more verbose.  Note that "info" is the default log level in
Swift.

And it disables the Heka configuration for Swift when "enable_swift"
is set to "no".  This prevents Heka from creating 15 empty Swift log
files in the logs volume.

Partially implements: blueprint heka

Change-Id: If7a7d0707e71be2957178e2d45b5de51b788232e

ansible/roles/common/templates/heka-global.toml.j2

@@ -11,9 +11,20 @@ filename = "lua_decoders/os_syslog.lua"
   [syslog_log_decoder.config]
   hostname = "{{ ansible_hostname }}"
 
+[swift_log_decoder]
+type = "SandboxDecoder"
+filename = "lua_decoders/os_swift_log.lua"
+  [swift_log_decoder.config]
+  hostname = "{{ ansible_hostname }}"
+
+[multi_log_decoder]
+type = "MultiDecoder"
+subs = ["syslog_log_decoder", "swift_log_decoder"]
+cascade_strategy = "first-wins"
+
 [syslog_input]
 type = "UdpInput"
 net = "unixgram"
 address = "/var/lib/kolla/heka/log"
-decoder = "syslog_log_decoder"
+decoder = "multi_log_decoder"
 splitter = "NullSplitter"

ansible/roles/common/templates/heka.json.j2

@@ -46,7 +46,7 @@
             "perm": "0600"
         }
 {%- if not loop.last %},{% endif %}
-{% endfor %}
+{% endfor -%}
 
     ]
 }

ansible/roles/swift/templates/account.conf.j2

@@ -6,7 +6,7 @@ mount_check = false
 log_address = /var/lib/kolla/heka/log
 log_name = {{ service_name }}
 log_facility = LOG_LOCAL0
-log_level = warning
+log_level = INFO
 
 [pipeline:main]
 pipeline = account-server

ansible/roles/swift/templates/container.conf.j2

@@ -6,7 +6,7 @@ mount_check = false
 log_address = /var/lib/kolla/heka/log
 log_name = {{ service_name }}
 log_facility = LOG_LOCAL0
-log_level = warning
+log_level = INFO
 
 [pipeline:main]
 pipeline = container-server

ansible/roles/swift/templates/object.conf.j2

@@ -7,7 +7,7 @@ mount_check = false
 log_address = /var/lib/kolla/heka/log
 log_name = {{ service_name }}
 log_facility = LOG_LOCAL0
-log_level = warning
+log_level = INFO
 
 [pipeline:main]
 {% if service_name == 'swift-object-expirer' %}

ansible/roles/swift/templates/proxy-server.conf.j2

@@ -5,7 +5,7 @@ bind_port = {{ swift_proxy_server_port }}
 log_address = /var/lib/kolla/heka/log
 log_name = {{ service_name }}
 log_facility = LOG_LOCAL0
-log_level = warning
+log_level = INFO
 
 [pipeline:main]
 pipeline = catch_errors gatekeeper healthcheck cache container_sync bulk ratelimit authtoken keystoneauth slo dlo proxy-server

docker/heka/plugins/decoders/os_swift_log.lua

@@ -0,0 +1,49 @@
+-- Copyright 2016 Mirantis, Inc.
+--
+-- 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 code in this file was inspired by Heka's rsyslog.lua decoder plugin.
+-- https://github.com/mozilla-services/heka/blob/master/sandbox/lua/decoders/rsyslog.lua
+
+local syslog = require "syslog"
+local utils = require "os_utils"
+
+local msg = {
+    Timestamp   = nil,
+    Type        = 'Syslog',
+    Hostname    = read_config("hostname"),
+    Payload     = nil,
+    Pid         = nil,
+    Severity    = nil,
+    Fields      = nil
+}
+
+-- See https://github.com/openstack/swift/blob/2a8b455/swift/common/utils.py#L1423-L1424
+local swift_grammar = syslog.build_rsyslog_grammar('<%PRI%>%programname%: %msg%')
+
+function process_message ()
+    local log = read_message("Payload")
+
+    local fields = swift_grammar:match(log)
+    if not fields then return -1 end
+
+    msg.Severity = fields.pri.severity
+    fields.syslogfacility = fields.pri.facility
+    fields.pri = nil
+
+    msg.Payload = fields.msg
+    fields.msg = nil
+
+    msg.Fields = fields
+    return utils.safe_inject_message(msg)
+end