func appendStats()

in agent/envoy_bootstrap/envoy_bootstrap.go [1106:1152]
40 lines of code
6 McCabe index (conditional complexity)

func appendStats(b *boot.Bootstrap, nodeId string) error {
	tags := make([]*metrics.TagSpecifier, 0)

	// Now that we support Service Connect, the nodeId can be of totally different arn format.
	// example arn for ECS TaskSet - arn:aws:ecs:us-west-2:123456789012:task-set/MyCluster/MyService/ecs-svc/1234567890123456789
	if strings.Contains(nodeId, ":task-set/") {
		metric_filter.AppendStatsTagRegexForServiceConnect(&tags)
	} else {
		res, err := getMeshResourceFromNodeId(nodeId)
		if err != nil {
			return err
		}

		enableStatsTags, err := env.Truthy("ENABLE_ENVOY_STATS_TAGS")
		if err != nil {
			return err
		}
		if enableStatsTags {
			tags = append(tags, &metrics.TagSpecifier{
				TagName: "appmesh.mesh",
				TagValue: &metrics.TagSpecifier_FixedValue{
					FixedValue: res.MeshName,
				},
			})

			tags = append(tags, &metrics.TagSpecifier{
				TagName: "appmesh." + res.SnakeCaseType,
				TagValue: &metrics.TagSpecifier_FixedValue{
					FixedValue: res.Name,
				},
			})
		}
		metric_filter.AppendStatsTagRegexForAppMesh(&tags, res)
		appendPortProtocolStatPrefixTagRegex(&tags)
	}

	// If there are no tags, then just bail out
	if len(tags) == 0 {
		return nil
	}
	bt := &boot.Bootstrap{
		StatsConfig: &metrics.StatsConfig{
			StatsTags: tags,
		},
	}
	return mergeBootstrap(b, bt)
}