metrics: enable input metrics

Signed-off-by: Shizuo Fujita <[email protected]>

Author: Watson1978

lib/fluent/command/fluentd.rb

@@ -155,7 +155,7 @@
   cmd_opts[:strict_config_value] = b
 }
 
-op.on('--enable-input-metrics', "Enable input plugin metrics on fluentd", TrueClass) {|b|
+op.on('--enable-input-metrics', "[DEPRECATED] Enable input plugin metrics on fluentd", TrueClass) {|b|
   cmd_opts[:enable_input_metrics] = b
 }
 

lib/fluent/root_agent.rb

@@ -86,7 +86,6 @@ def initialize(log:, system_config: SystemConfig.new, start_in_parallel: false)
       @without_source = system_config.without_source || false
       @source_only_mode = SourceOnlyMode.new(system_config.with_source_only, start_in_parallel)
       @source_only_buffer_agent = nil
-      @enable_input_metrics = system_config.enable_input_metrics || false
 
       suppress_interval(system_config.emit_error_log_interval) unless system_config.emit_error_log_interval.nil?
     end
@@ -414,9 +413,7 @@ def add_source(type, conf)
       input.context_router = @event_router
       input.configure(conf)
       input.event_emitter_apply_source_only if @source_only_mode.enabled?
-      if @enable_input_metrics
-        @event_router.add_metric_callbacks(input.plugin_id, Proc.new {|es| input.metric_callback(es) })
-      end
+      @event_router.add_metric_callbacks(input.plugin_id, Proc.new {|es| input.metric_callback(es) })
       @inputs << input
 
       input

lib/fluent/supervisor.rb

@@ -631,7 +631,6 @@ def self.default_options
         ignore_repeated_log_interval: nil,
         without_source: nil,
         with_source_only: nil,
-        enable_input_metrics: nil,
         enable_size_metrics: nil,
         use_v1_config: true,
         strict_config_value: nil,

lib/fluent/system_config.rb

@@ -51,7 +51,7 @@ class SystemConfig
     config_param :strict_config_value, :bool, default: nil
     config_param :enable_msgpack_time_support, :bool, default: nil
     config_param :disable_shared_socket, :bool, default: nil
-    config_param :enable_input_metrics, :bool, default: nil
+    config_param :enable_input_metrics, :bool, default: nil, deprecated: "input metrics is always enabled. This parameter is existed for compatibility."
     config_param :enable_size_metrics, :bool, default: nil
     config_param :enable_jit, :bool, default: false
     config_param :file_permission, default: nil do |v|

test/test_root_agent.rb

@@ -17,7 +17,6 @@ def test_initialize
   data(
     'suppress interval' => [{'emit_error_log_interval' => 30}, {:@suppress_emit_error_log_interval => 30}],
     'without source' => [{'without_source' => true}, {:@without_source => true}],
-    'enable input metrics' => [{'enable_input_metrics' => true}, {:@enable_input_metrics => true}],
     )
   def test_initialize_with_opt(data)
     opt, expected = data