Collecting system metrics using Golang

This is a creation in Article, where the information may have evolved or changed.

Common.go

// copy code from github.com/shirou/gopsutilpackage sysimport ("bufio""os""strings")// ReadLines reads contents from file and splits them by new line.// A convenience wrapper to ReadLinesOffsetN(filename, 0, -1).func readLines(filename string) ([]string, error) {return readLinesOffsetN(filename, 0, -1)}// ReadLines reads contents from file and splits them by new line.// The offset tells at which line number to start.// The count determines the number of lines to read (starting from offset)://   n >= 0: at most n lines//   n < 0: whole filefunc readLinesOffsetN(filename string, offset uint, n int) ([]string, error) {f, err := os.Open(filename)if err != nil {return []string{""}, err}defer f.Close()var ret []stringr := bufio.NewReader(f)for i := 0; i < n+int(offset) || n < 0; i++ {line, err := r.ReadString('\n')if err != nil {break}if i < int(offset) {continue}ret = append(ret, strings.Trim(line, "\n"))}return ret, nil}

Sys.go

Copy code from github.com/shirou/gopsutil//almost the same, but change a lot, especially the returned Structpackage Sy Simport ("Errors" "Io/ioutil" "StrConv" "strings") type SysStat struct {///proc/loadavgload1 float64load5 FLOAT64LOAD15      float64///proc/meminfototal uint64available uint64used uint64usedpercent float64free uint64Active  Uint64inactive uint64buffers uint64cached uint64wired uint64shared uint64///proc/net/dev//sum Of all Interfacesname stringbytessent uint64bytesrecv uint64packetssent uint64packetsrecv uint64///proc/statC PU stringuser float64system float64idle float64nice float64iowait FLOAT64IRQ float64softi RQ float64steal float64guest Float64guestnice float64stolen float64}func getsysstat () *SysStat {stat: = new (S Ysstat) Stat.cputimes () stat.netiocounters () stat.virtualmemory () Stat.loadavg () return Stat}func (stat *SysStat) Cputimes () error {filename: = "/proc/staT "var lines = []string{}lines, _ = readlinesoffsetn (filename, 0, 1) Err: = Stat.parsestatline (lines[0]) if err! = Nil {retur n Err}return nil}func (stat *sysstat) Parsestatline (line string), error {fields: = strings. Fields (line) if strings. Hasprefix (Fields[0], "cpu") = = false {return errors. New ("not contain CPU")}CPU: = fields[0]if CPU = = "CPU" {CPU = "Cpu-total"}user, err: = StrConv. Parsefloat (Fields[1], up) if err! = Nil {return Err}nice, err: = StrConv. Parsefloat (Fields[2], up) if err! = Nil {return Err}system, err: = StrConv. Parsefloat (Fields[3], up) if err! = Nil {return err}idle, err: = StrConv. Parsefloat (Fields[4], up) if err! = Nil {return err}iowait, err: = StrConv. Parsefloat (Fields[5], up) if err! = Nil {return ERR}IRQ, err: = StrConv. Parsefloat (Fields[6], up) if err! = Nil {return ERR}SOFTIRQ, err: = StrConv. Parsefloat (Fields[7], up) if err! = Nil {return Err}stolen, err: = StrConv. Parsefloat (Fields[8], max) if err! = Nil {return Err}cpu_tick: = float64 (+)//todo:how to get _SC_CLK_TCK Stat. CPU = Cpustat. user = float64 (user)/Cpu_tickstat. Nice = Float64 (Nice)/Cpu_tickstat. System = Float64 (System)/Cpu_tickstat. Idle = float64 (idle)/Cpu_tickstat. iowait = float64 (iowait)/Cpu_tickstat. IRQ = float64 (IRQ)/Cpu_tickstat. SOFTIRQ = float64 (SOFTIRQ)/Cpu_tickstat. Stolen = float64 (Stolen)/Cpu_tickif len (Fields) > 9 {//Linux >= 2.6.11steal, err: = StrConv. Parsefloat (Fields[9], up) if err! = Nil {return err}stat. Steal = Float64 (steal)}if len (fields) > {//Linux >= 2.6.24guest, err: = StrConv. Parsefloat (fields[10], up) if err! = Nil {return err}stat. Guest = Float64 (guest)}if len (fields) > {//Linux >= 3.2.0guestNice, err: = StrConv. Parsefloat (fields[11], up) if err! = Nil {return err}stat. Guestnice = float64 (guestnice)}return nil}type netiocountersstat struct {Name stringbytessent uint64bytesrecv u Int64packetssent uint64packetsrecv Uint64}func (stat *sysstat) netiocounters () error {filename: = "/proc/net/dev" lines, ERR: = ReadLines (filename) if err! = Nil {return Err}statlen: = Len (lines)-1all: = Make ([]netiocountersstat, 0, Statlen) for _, line: = R Ange lines[2:] {parts: = strings. SPLITN (Line, ":", 2) If Len (parts)! = 2 {continue}interfacename: = strings. Trimspace (Parts[0]) if InterfaceName = = "" {continue}fields: = strings. Fields (strings. Trimspace (Parts[1])) BYTESRECV, err: = StrConv. Parseuint (Fields[0], ten, max) if err! = Nil {return ERR}PACKETSRECV, err: = StrConv. Parseuint (Fields[1], ten, max) if err! = Nil {return err}bytessent, err: = StrConv. Parseuint (Fields[8], ten, max) if err! = Nil {return err}packetssent, err: = StrConv. Parseuint (Fields[9], ten, max) if err! = Nil {return Err}nic: = Netiocountersstat{name:interfacename,bytesrecv:byt Esrecv,packetsrecv:packetsrecv,bytessent:bytessent,packetssent:packetssent}all = append (all, Nic)}return Stat.getnetiocountersall (All)}func (stat *sysstat) getnetiocountersall (n []netiocountersstat) error {Stat. Name = "All-interfaces" for _, Nic: = Range N {Stat. BytesreCV + = nic. Bytesrecvstat.packetsrecv + = nic. Packetsrecvstat.bytessent + = nic. Bytessentstat.packetssent + = nic. Packetssent}return Nil}func (stat *sysstat) virtualmemory () error {filename: = "/proc/meminfo" lines, _: = ReadLines (filen AME) for _, Line: = Range lines {fields: = strings. Split (line, ': ') If Len (fields)! = 2 {continue}key: = strings. Trimspace (Fields[0]) Value: = Strings. Trimspace (fields[1]) value = strings. Replace (Value, "KB", "",-1) t, err: = StrConv. Parseuint (value, ten, max) if err! = Nil {return Err}switch key {case "Memtotal": Stat. Total = T * 1000case "Memfree": Stat. Free = T * 1000case "buffers": Stat. buffers = T * 1000case "Cached": Stat. Cached = T * 1000case "Active": Stat. Active = T * 1000case "Inactive": Stat. Inactive = T * 1000}}stat. Available = Stat. Free + Stat. Buffers + Stat. cachedstat.used = Stat. Total-stat. Freestat.usedpercent = float64 (Stat. total-stat.available)/float64 (Stat. Total) * 100.0return Nil}func (stat *sysstat) Loadavg () error {filename: = '/proc/loadavg ' line, ERR: = Ioutil. ReadFile (filename) if err! = Nil {return err}values: = Strings. Fields (String) load1, err: = StrConv. Parsefloat (Values[0], up) if err! = Nil {return ERR}LOAD5, err: = StrConv. Parsefloat (Values[1], up) if err! = Nil {return err}load15, err: = StrConv. Parsefloat (Values[2], up) if err! = Nil {return err}stat. Load1 = Load1stat. LOAD5 = Load5stat. LOAD15 = Load15return Nil}