Class: LogStash::Agent

Inherits:
Object
  • Object
show all
Includes:
Util::Loggable
Defined in:
lib/logstash/agent.rb

Constant Summary collapse

STARTED_AT =
Time.now.freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(settings = LogStash::SETTINGS, source_loader = nil) ⇒ Agent

initialize method for LogStash::Agent

Parameters:

  • params (Hash)

    potential parameters are: :name [String] - identifier for the agent :auto_reload [Boolean] - enable reloading of pipelines :reload_interval [Integer] - reload pipelines every X seconds



31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
# File 'lib/logstash/agent.rb', line 31

def initialize(settings = LogStash::SETTINGS, source_loader = nil)
  @logger = self.class.logger
  @settings = settings
  @auto_reload = setting("config.reload.automatic")
  @ephemeral_id = SecureRandom.uuid

  # Mutex to synchonize in the exclusive method
  # Initial usage for the Ruby pipeline initialization which is not thread safe
  @webserver_control_lock = Mutex.new

  @convergence_lock = Mutex.new

  # Special bus object for inter-pipelines communications. Used by the `pipeline` input/output
  @pipeline_bus = org.logstash.plugins.pipeline.PipelineBus.new

  @pipelines_registry = LogStash::PipelinesRegistry.new

  @name = setting("node.name")
  @http_host = setting("http.host")
  @http_port = setting("http.port")
  @http_environment = setting("http.environment")
  # Generate / load the persistent uuid
  id

  # Set the global FieldReference parsing mode
  if @settings.set?('config.field_reference.parser')
    # TODO: i18n
    logger.warn("deprecated setting `config.field_reference.parser` set; field reference parsing is strict by default")
  end

  # This is for backward compatibility in the tests
  if source_loader.nil?
    @source_loader = LogStash::Config::SourceLoader.new
    @source_loader.add_source(LogStash::Config::Source::Local.new(@settings))
  else
    @source_loader = source_loader
  end

  # Normalize time interval to seconds
  @reload_interval = setting("config.reload.interval") / 1_000_000_000.0

  @collect_metric = setting("metric.collect")

  # Create the collectors and configured it with the library
  configure_metrics_collectors

  @state_resolver = LogStash::StateResolver.new(metric)

  @pipeline_reload_metric = metric.namespace([:stats, :pipelines])
  @instance_reload_metric = metric.namespace([:stats, :reloads])
  initialize_agent_metrics

  @dispatcher = LogStash::EventDispatcher.new(self)
  LogStash::PLUGIN_REGISTRY.hooks.register_emitter(self.class, dispatcher)
  dispatcher.fire(:after_initialize)

  @running = Concurrent::AtomicBoolean.new(false)
end

Instance Attribute Details

#dispatcherObject (readonly)

Returns the value of attribute dispatcher.



23
24
25
# File 'lib/logstash/agent.rb', line 23

def dispatcher
  @dispatcher
end

#ephemeral_idObject (readonly)

Returns the value of attribute ephemeral_id.



23
24
25
# File 'lib/logstash/agent.rb', line 23

def ephemeral_id
  @ephemeral_id
end

#loggerObject

Returns the value of attribute logger.



24
25
26
# File 'lib/logstash/agent.rb', line 24

def logger
  @logger
end

#metricObject (readonly)

Returns the value of attribute metric.



23
24
25
# File 'lib/logstash/agent.rb', line 23

def metric
  @metric
end

#nameObject (readonly)

Returns the value of attribute name.



23
24
25
# File 'lib/logstash/agent.rb', line 23

def name
  @name
end

#pipeline_busObject (readonly)

Returns the value of attribute pipeline_bus.



23
24
25
# File 'lib/logstash/agent.rb', line 23

def pipeline_bus
  @pipeline_bus
end

#settingsObject (readonly)

Returns the value of attribute settings.



23
24
25
# File 'lib/logstash/agent.rb', line 23

def settings
  @settings
end

Instance Method Details

#auto_reload?Boolean

Returns:

  • (Boolean)


136
137
138
# File 'lib/logstash/agent.rb', line 136

def auto_reload?
  @auto_reload
end

#converge_state_and_updateObject



148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
# File 'lib/logstash/agent.rb', line 148

def converge_state_and_update
  results = @source_loader.fetch

  unless results.success?
    if auto_reload?
      logger.debug("Could not fetch the configuration to converge, will retry", :message => results.error, :retrying_in => @reload_interval)
      return
    else
      raise "Could not fetch the configuration, message: #{results.error}"
    end
  end

  converge_result = resolve_actions_and_converge_state(results.response)
  update_metrics(converge_result)

  logger.info(
      "Pipelines running",
      :count => running_pipelines.size,
      :running_pipelines => running_pipelines.keys,
      :non_running_pipelines => non_running_pipelines.keys
  ) if converge_result.success? && converge_result.total > 0

  dispatch_events(converge_result)

  converge_result
rescue => e
  logger.error("An exception happened when converging configuration", :exception => e.class, :message => e.message, :backtrace => e.backtrace)
end

#executeObject



90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
# File 'lib/logstash/agent.rb', line 90

def execute
  @thread = Thread.current # this var is implicitly used by Stud.stop?
  LogStash::Util.set_thread_name("Agent thread")
  logger.debug("Starting agent")

  transition_to_running

  converge_state_and_update

  start_webserver

  if auto_reload?
    # `sleep_then_run` instead of firing the interval right away
    Stud.interval(@reload_interval, :sleep_then_run => true) do
      # TODO(ph) OK, in reality, we should get out of the loop, but I am
      # worried about the implication of that change so instead when we are stopped
      # we don't converge.
      #
      # Logstash currently expect to be block here, the signal will force a kill on the agent making
      # the agent thread unblock
      #
      # Actually what we really need is one more state:
      #
      # init => running => stopping => stopped
      converge_state_and_update unless stopped?
    end
  else
    # exit with error status if the initial converge_state_and_update did not create any pipeline
    return 1 if @pipelines_registry.empty?

    while !Stud.stop?
      # exit if all pipelines are terminated and none are reloading
      break if no_pipeline?

      # exit if there are no user defined pipelines (not system pipeline) and none are reloading
      break if !running_user_defined_pipelines?

      sleep(0.5)
    end
  end

  return 0
ensure
  transition_to_stopped
end

#get_pipeline(pipeline_id) ⇒ Object

Backward compatibility proxies to the PipelineRegistry



238
239
240
# File 'lib/logstash/agent.rb', line 238

def get_pipeline(pipeline_id)
  @pipelines_registry.get_pipeline(pipeline_id)
end

#idObject



196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
# File 'lib/logstash/agent.rb', line 196

def id
  return @id if @id

  uuid = nil
  if ::File.exists?(id_path)
    begin
      uuid = ::File.open(id_path) {|f| f.each_line.first.chomp }
    rescue => e
      logger.warn("Could not open persistent UUID file!",
                  :path => id_path,
                  :error => e.message,
                  :class => e.class.name)
    end
  end

  if !uuid
    uuid = SecureRandom.uuid
    logger.info("No persistent UUID file found. Generating new UUID",
                :uuid => uuid,
                :path => id_path)
    begin
      ::File.open(id_path, 'w') {|f| f.write(uuid) }
    rescue => e
      logger.warn("Could not write persistent UUID file! Will use ephemeral UUID",
                  :uuid => uuid,
                  :path => id_path,
                  :error => e.message,
                  :class => e.class.name)
    end
  end

  @id = uuid
end

#id_pathObject



230
231
232
# File 'lib/logstash/agent.rb', line 230

def id_path
  @id_path ||= ::File.join(settings.get("path.data"), "uuid")
end

#no_pipeline?Boolean

Returns:

  • (Boolean)


270
271
272
# File 'lib/logstash/agent.rb', line 270

def no_pipeline?
  @pipelines_registry.running_pipelines.empty?
end

#non_running_pipelinesObject



250
251
252
# File 'lib/logstash/agent.rb', line 250

def non_running_pipelines
  @pipelines_registry.non_running_pipelines
end

#pipelines_countObject



242
243
244
# File 'lib/logstash/agent.rb', line 242

def pipelines_count
  @pipelines_registry.size
end

#running?Boolean

Returns:

  • (Boolean)


140
141
142
# File 'lib/logstash/agent.rb', line 140

def running?
  @running.true?
end

#running_pipelinesObject



246
247
248
# File 'lib/logstash/agent.rb', line 246

def running_pipelines
 @pipelines_registry.running_pipelines
end

#running_pipelines?Boolean

Returns:

  • (Boolean)


254
255
256
# File 'lib/logstash/agent.rb', line 254

def running_pipelines?
  @pipelines_registry.running_pipelines.any?
end

#running_pipelines_countObject



258
259
260
# File 'lib/logstash/agent.rb', line 258

def running_pipelines_count
  @pipelines_registry.running_pipelines.size
end

#running_user_defined_pipelinesObject



266
267
268
# File 'lib/logstash/agent.rb', line 266

def running_user_defined_pipelines
  @pipelines_registry.running_user_defined_pipelines
end

#running_user_defined_pipelines?Boolean

Returns:

  • (Boolean)


262
263
264
# File 'lib/logstash/agent.rb', line 262

def running_user_defined_pipelines?
  @pipelines_registry.running_user_defined_pipelines.any?
end

#shutdownObject



184
185
186
187
188
189
190
191
192
193
194
# File 'lib/logstash/agent.rb', line 184

def shutdown
  # Since we're shutting down we need to shutdown the DAG of pipelines that are talking to each other
  # in order of dependency.
  pipeline_bus.setBlockOnUnlisten(true)

  stop_collecting_metrics
  transition_to_stopped
  converge_result = shutdown_pipelines
  stop_webserver
  converge_result
end

#stopped?Boolean

Returns:

  • (Boolean)


144
145
146
# File 'lib/logstash/agent.rb', line 144

def stopped?
  @running.false?
end

#uptimeInteger

Calculate the Logstash uptime in milliseconds

Returns:

  • (Integer)

    Uptime in milliseconds



180
181
182
# File 'lib/logstash/agent.rb', line 180

def uptime
  ((Time.now.to_f - STARTED_AT.to_f) * 1000.0).to_i
end