func parseContainerStats()

in plugins/inputs/docker/docker.go [573:746]
154 lines of code
19 McCabe index (conditional complexity)

func parseContainerStats(
	stat *types.StatsJSON,
	acc telegraf.Accumulator,
	tags map[string]string,
	id string,
	perDevice bool,
	total bool,
	daemonOSType string,
) {
	tm := stat.Read

	if tm.Before(time.Unix(0, 0)) {
		tm = time.Now()
	}

	memfields := map[string]interface{}{
		"container_id": id,
	}

	memstats := []string{
		"active_anon",
		"active_file",
		"cache",
		"hierarchical_memory_limit",
		"inactive_anon",
		"inactive_file",
		"mapped_file",
		"pgfault",
		"pgmajfault",
		"pgpgin",
		"pgpgout",
		"rss",
		"rss_huge",
		"total_active_anon",
		"total_active_file",
		"total_cache",
		"total_inactive_anon",
		"total_inactive_file",
		"total_mapped_file",
		"total_pgfault",
		"total_pgmajfault",
		"total_pgpgin",
		"total_pgpgout",
		"total_rss",
		"total_rss_huge",
		"total_unevictable",
		"total_writeback",
		"unevictable",
		"writeback",
	}
	for _, field := range memstats {
		if value, ok := stat.MemoryStats.Stats[field]; ok {
			memfields[field] = value
		}
	}
	if stat.MemoryStats.Failcnt != 0 {
		memfields["fail_count"] = stat.MemoryStats.Failcnt
	}

	if daemonOSType != "windows" {
		memfields["limit"] = stat.MemoryStats.Limit
		memfields["max_usage"] = stat.MemoryStats.MaxUsage

		mem := CalculateMemUsageUnixNoCache(stat.MemoryStats)
		memLimit := float64(stat.MemoryStats.Limit)
		memfields["usage"] = uint64(mem)
		memfields["usage_percent"] = CalculateMemPercentUnixNoCache(memLimit, mem)
	} else {
		memfields["commit_bytes"] = stat.MemoryStats.Commit
		memfields["commit_peak_bytes"] = stat.MemoryStats.CommitPeak
		memfields["private_working_set"] = stat.MemoryStats.PrivateWorkingSet
	}

	acc.AddFields("docker_container_mem", memfields, tags, tm)

	cpufields := map[string]interface{}{
		"usage_total":                  stat.CPUStats.CPUUsage.TotalUsage,
		"usage_in_usermode":            stat.CPUStats.CPUUsage.UsageInUsermode,
		"usage_in_kernelmode":          stat.CPUStats.CPUUsage.UsageInKernelmode,
		"usage_system":                 stat.CPUStats.SystemUsage,
		"throttling_periods":           stat.CPUStats.ThrottlingData.Periods,
		"throttling_throttled_periods": stat.CPUStats.ThrottlingData.ThrottledPeriods,
		"throttling_throttled_time":    stat.CPUStats.ThrottlingData.ThrottledTime,
		"container_id":                 id,
	}

	if daemonOSType != "windows" {
		previousCPU := stat.PreCPUStats.CPUUsage.TotalUsage
		previousSystem := stat.PreCPUStats.SystemUsage
		cpuPercent := CalculateCPUPercentUnix(previousCPU, previousSystem, stat)
		cpufields["usage_percent"] = cpuPercent
	} else {
		cpuPercent := calculateCPUPercentWindows(stat)
		cpufields["usage_percent"] = cpuPercent
	}

	cputags := copyTags(tags)
	cputags["cpu"] = "cpu-total"
	acc.AddFields("docker_container_cpu", cpufields, cputags, tm)

	// If we have OnlineCPUs field, then use it to restrict stats gathering to only Online CPUs
	// (https://github.com/moby/moby/commit/115f91d7575d6de6c7781a96a082f144fd17e400)
	var percpuusage []uint64
	if stat.CPUStats.OnlineCPUs > 0 {
		percpuusage = stat.CPUStats.CPUUsage.PercpuUsage[:stat.CPUStats.OnlineCPUs]
	} else {
		percpuusage = stat.CPUStats.CPUUsage.PercpuUsage
	}

	for i, percpu := range percpuusage {
		percputags := copyTags(tags)
		percputags["cpu"] = fmt.Sprintf("cpu%d", i)
		fields := map[string]interface{}{
			"usage_total":  percpu,
			"container_id": id,
		}
		acc.AddFields("docker_container_cpu", fields, percputags, tm)
	}

	totalNetworkStatMap := make(map[string]interface{})
	for network, netstats := range stat.Networks {
		netfields := map[string]interface{}{
			"rx_dropped":   netstats.RxDropped,
			"rx_bytes":     netstats.RxBytes,
			"rx_errors":    netstats.RxErrors,
			"tx_packets":   netstats.TxPackets,
			"tx_dropped":   netstats.TxDropped,
			"rx_packets":   netstats.RxPackets,
			"tx_errors":    netstats.TxErrors,
			"tx_bytes":     netstats.TxBytes,
			"container_id": id,
		}
		// Create a new network tag dictionary for the "network" tag
		if perDevice {
			nettags := copyTags(tags)
			nettags["network"] = network
			acc.AddFields("docker_container_net", netfields, nettags, tm)
		}
		if total {
			for field, value := range netfields {
				if field == "container_id" {
					continue
				}

				var uintV uint64
				switch v := value.(type) {
				case uint64:
					uintV = v
				case int64:
					uintV = uint64(v)
				default:
					continue
				}

				_, ok := totalNetworkStatMap[field]
				if ok {
					totalNetworkStatMap[field] = totalNetworkStatMap[field].(uint64) + uintV
				} else {
					totalNetworkStatMap[field] = uintV
				}
			}
		}
	}

	// totalNetworkStatMap could be empty if container is running with --net=host.
	if total && len(totalNetworkStatMap) != 0 {
		nettags := copyTags(tags)
		nettags["network"] = "total"
		totalNetworkStatMap["container_id"] = id
		acc.AddFields("docker_container_net", totalNetworkStatMap, nettags, tm)
	}

	gatherBlockIOMetrics(stat, acc, tags, tm, id, perDevice, total)
}