WIP

Author: Watson1978

lib/fluent/plugin/in_opentelemetry_metrics.rb

@@ -21,10 +21,13 @@ class OpentelemetryMetricsInput < Input
     desc "The tag of the event."
     config_param :tag, :string
 
+    desc "The prefix of metric name."
+    config_param :metric_name_prefix, :string, default: "fluentd_"
+
     def start
       super
 
-      @metrics = Metrics.new
+      @metrics = Metrics.new(metric_name_prefix: metric_name_prefix)
       timer_execute(:in_opentelemetry_metrics, @emit_interval) do
         router.emit(@tag, Fluent::EventTime.now, { "type" => Opentelemetry::RECORD_TYPE_METRICS, "message" => JSON.generate(@metrics.metrics_data) })
       end
@@ -41,8 +44,9 @@ def to_nano_sec
     class Metrics
       using Extension
 
-      def initialize
+      def initialize(metric_name_prefix:)
         @start_time_unix_nano = Time.now.to_nano_sec
+        @metric_name_prefix = metric_name_prefix.to_s
       end
 
       def metrics_data
@@ -67,14 +71,14 @@ def scope_metrics
         time = Time.now
 
         metrics = []
-        monitor.plugins_info_all.map do |record|
+        monitor.plugins_info_all.each do |record|
           attrs = {
             plugin_id: record["plugin_id"],
             plugin: "#{record['plugin_category']}_#{record['type']}",
             plugin_category: record["plugin_category"],
             plugin_type: record["type"]
           }
-          metrics_value(time, record, attrs, metrics)
+          metrics.concat(metrics_value(time, record, attrs))
         end
 
         [
@@ -88,27 +92,27 @@ def scope_metrics
         ]
       end
 
-      def metrics_value(time, record, attrs, metrics = [])
+      def metrics_value(time, record, attrs)
         attributes = attrs.map { |k, v| string_value_attribute(k, v) }
 
-        record.each do |key, value|
-          if value.is_a?(Numeric)
-            metrics << {
-              "name" => "fluentd_" + key.to_s,
-              "unit" => "1",
-              # TODO: "description"
-              "gauge" => {
-                "dataPoints" => [
-                  {
-                    "startTimeUnixNano" => @start_time_unix_nano.to_s,
-                    "timeUnixNano" => time.to_nano_sec.to_s,
-                    "asDouble" => value,
-                    "attributes" => attributes
-                  }
-                ]
-              }
+        record.each_with_object([]) do |(key, value), metrics|
+          next unless value.is_a?(Numeric)
+
+          metrics << {
+            "name" => @metric_name_prefix + key.to_s,
+            "unit" => "1",
+            # TODO: "description"
+            "gauge" => {
+              "dataPoints" => [
+                {
+                  "startTimeUnixNano" => @start_time_unix_nano.to_s,
+                  "timeUnixNano" => time.to_nano_sec.to_s,
+                  "asDouble" => value,
+                  "attributes" => attributes
+                }
+              ]
             }
-          end
+          }
         end
       end