package ping import ( "errors" "os/exec" "strconv" "strings" "sync" "github.com/influxdata/telegraf" "github.com/influxdata/telegraf/plugins/inputs" ) // HostPinger is a function that runs the "ping" function using a list of // passed arguments. This can be easily switched with a mocked ping function // for unit test purposes (see ping_test.go) type HostPinger func(args ...string) (string, error) type Ping struct { // Interval at which to ping (ping -i ) PingInterval float64 `toml:"ping_interval"` // Number of pings to send (ping -c ) Count int // Ping timeout, in seconds. 0 means no timeout (ping -t ) Timeout float64 // Interface to send ping from (ping -I ) Interface string // URLs to ping Urls []string // host ping function pingHost HostPinger } func (_ *Ping) Description() string { return "Ping given url(s) and return statistics" } var sampleConfig = ` # urls to ping urls = ["www.google.com"] # required # number of pings to send (ping -c ) count = 1 # required # interval, in s, at which to ping. 0 == default (ping -i ) ping_interval = 0.0 # ping timeout, in s. 0 == no timeout (ping -t ) timeout = 0.0 # interface to send ping from (ping -I ) interface = "" ` func (_ *Ping) SampleConfig() string { return sampleConfig } func (p *Ping) Gather(acc telegraf.Accumulator) error { var wg sync.WaitGroup errorChannel := make(chan error, len(p.Urls)*2) // Spin off a go routine for each url to ping for _, url := range p.Urls { wg.Add(1) go func(url string, acc telegraf.Accumulator) { defer wg.Done() args := p.args(url) out, err := p.pingHost(args...) if err != nil { // Combine go err + stderr output errorChannel <- errors.New( strings.TrimSpace(out) + ", " + err.Error()) } tags := map[string]string{"url": url} trans, rec, avg, err := processPingOutput(out) if err != nil { // fatal error errorChannel <- err return } // Calculate packet loss percentage loss := float64(trans-rec) / float64(trans) * 100.0 fields := map[string]interface{}{ "packets_transmitted": trans, "packets_received": rec, "percent_packet_loss": loss, } if avg > 0 { fields["average_response_ms"] = avg } acc.AddFields("ping", fields, tags) }(url, acc) } wg.Wait() close(errorChannel) // Get all errors and return them as one giant error errorStrings := []string{} for err := range errorChannel { errorStrings = append(errorStrings, err.Error()) } if len(errorStrings) == 0 { return nil } return errors.New(strings.Join(errorStrings, "\n")) } func hostPinger(args ...string) (string, error) { c := exec.Command("ping", args...) out, err := c.CombinedOutput() return string(out), err } // args returns the arguments for the 'ping' executable func (p *Ping) args(url string) []string { // Build the ping command args based on toml config args := []string{"-c", strconv.Itoa(p.Count)} if p.PingInterval > 0 { args = append(args, "-i", strconv.FormatFloat(p.PingInterval, 'f', 1, 64)) } if p.Timeout > 0 { args = append(args, "-t", strconv.FormatFloat(p.Timeout, 'f', 1, 64)) } if p.Interface != "" { args = append(args, "-I", p.Interface) } args = append(args, url) return args } // processPingOutput takes in a string output from the ping command, like: // // PING www.google.com (173.194.115.84): 56 data bytes // 64 bytes from 173.194.115.84: icmp_seq=0 ttl=54 time=52.172 ms // 64 bytes from 173.194.115.84: icmp_seq=1 ttl=54 time=34.843 ms // // --- www.google.com ping statistics --- // 2 packets transmitted, 2 packets received, 0.0% packet loss // round-trip min/avg/max/stddev = 34.843/43.508/52.172/8.664 ms // // It returns (, , ) func processPingOutput(out string) (int, int, float64, error) { var trans, recv int var avg float64 // Set this error to nil if we find a 'transmitted' line err := errors.New("Fatal error processing ping output") lines := strings.Split(out, "\n") for _, line := range lines { if strings.Contains(line, "transmitted") && strings.Contains(line, "received") { err = nil stats := strings.Split(line, ", ") // Transmitted packets trans, err = strconv.Atoi(strings.Split(stats[0], " ")[0]) if err != nil { return trans, recv, avg, err } // Received packets recv, err = strconv.Atoi(strings.Split(stats[1], " ")[0]) if err != nil { return trans, recv, avg, err } } else if strings.Contains(line, "min/avg/max") { stats := strings.Split(line, " = ")[1] avg, err = strconv.ParseFloat(strings.Split(stats, "/")[1], 64) if err != nil { return trans, recv, avg, err } } } return trans, recv, avg, err } func init() { inputs.Add("ping", func() telegraf.Input { return &Ping{pingHost: hostPinger} }) }