Merge pull request #472 from Dentrax/netstat-refactor

Separate NetStat parsing logic

netstat.go

@@ -15,6 +15,7 @@ package procfs
 
 import (
 	"bufio"
+	"io"
 	"os"
 	"path/filepath"
 	"strconv"
@@ -42,27 +43,43 @@ func (fs FS) NetStat() ([]NetStat, error) {
 			return nil, err
 		}
 
-		netStatFile := NetStat{
-			Filename: filepath.Base(filePath),
-			Stats:    make(map[string][]uint64),
+		procNetstat, err := parseNetstat(file)
+		if err != nil {
+			return nil, err
+		}
+		procNetstat.Filename = filepath.Base(filePath)
+
+		netStatsTotal = append(netStatsTotal, procNetstat)
+	}
+	return netStatsTotal, nil
+}
+
+// parseNetstat parses the metrics from `/proc/net/stat/` file
+// and returns a NetStat structure.
+func parseNetstat(r io.Reader) (NetStat, error) {
+	var (
+		scanner = bufio.NewScanner(r)
+		netStat = NetStat{
+			Stats: make(map[string][]uint64),
 		}
-		scanner := bufio.NewScanner(file)
-		scanner.Scan()
-		// First string is always a header for stats
-		var headers []string
-		headers = append(headers, strings.Fields(scanner.Text())...)
+	)
+
+	scanner.Scan()
 
-		// Other strings represent per-CPU counters
-		for scanner.Scan() {
-			for num, counter := range strings.Fields(scanner.Text()) {
-				value, err := strconv.ParseUint(counter, 16, 64)
-				if err != nil {
-					return nil, err
-				}
-				netStatFile.Stats[headers[num]] = append(netStatFile.Stats[headers[num]], value)
+	// First string is always a header for stats
+	var headers []string
+	headers = append(headers, strings.Fields(scanner.Text())...)
+
+	// Other strings represent per-CPU counters
+	for scanner.Scan() {
+		for num, counter := range strings.Fields(scanner.Text()) {
+			value, err := strconv.ParseUint(counter, 16, 64)
+			if err != nil {
+				return NetStat{}, err
 			}
+			netStat.Stats[headers[num]] = append(netStat.Stats[headers[num]], value)
 		}
-		netStatsTotal = append(netStatsTotal, netStatFile)
 	}
-	return netStatsTotal, nil
+
+	return netStat, nil
 }

proc_netstat.go

@@ -174,14 +174,14 @@ func (p Proc) Netstat() (ProcNetstat, error) {
 	if err != nil {
 		return ProcNetstat{PID: p.PID}, err
 	}
-	procNetstat, err := parseNetstat(bytes.NewReader(data), filename)
+	procNetstat, err := parseProcNetstat(bytes.NewReader(data), filename)
 	procNetstat.PID = p.PID
 	return procNetstat, err
 }
 
-// parseNetstat parses the metrics from proc/<pid>/net/netstat file
+// parseProcNetstat parses the metrics from proc/<pid>/net/netstat file
 // and returns a ProcNetstat structure.
-func parseNetstat(r io.Reader, fileName string) (ProcNetstat, error) {
+func parseProcNetstat(r io.Reader, fileName string) (ProcNetstat, error) {
 	var (
 		scanner     = bufio.NewScanner(r)
 		procNetstat = ProcNetstat{}