Warn without error when processes input is started on Windows (influx…

…data#6891)

plugins/inputs/processes/README.md

@@ -6,7 +6,9 @@ them by status (zombie, sleeping, running, etc.)
 On linux this plugin requires access to procfs (/proc), on other OSes
 it requires access to execute `ps`.
 
-### Configuration:
+**Supported Platforms**: Linux, FreeBSD, Darwin
+
+### Configuration
 
 ```toml
 # Get the number of processes and group them by status
@@ -19,9 +21,10 @@ Using the environment variable `HOST_PROC` the plugin will retrieve process info
 
 `docker run -v /proc:/rootfs/proc:ro -e HOST_PROC=/rootfs/proc`
 
-### Measurements & Fields:
+### Metrics
 
 - processes
+  - fields:
     - blocked (aka disk sleep or uninterruptible sleep)
     - running
     - sleeping
@@ -53,14 +56,8 @@ Linux  FreeBSD  Darwin  meaning
   W       W      none   paging (linux kernel < 2.6 only), wait (freebsd)
 ```
 
-### Tags:
-
-None
-
-### Example Output:
+### Example Output
 
 ```
-$ telegraf --config ~/ws/telegraf.conf --input-filter processes --test
-* Plugin: processes, Collection 1
-> processes blocked=8i,running=1i,sleeping=265i,stopped=0i,total=274i,zombie=0i,dead=0i,paging=0i,total_threads=687i 1457478636980905042
+processes blocked=8i,running=1i,sleeping=265i,stopped=0i,total=274i,zombie=0i,dead=0i,paging=0i,total_threads=687i 1457478636980905042
 ```

plugins/inputs/processes/processes.go

@@ -1,241 +1,7 @@
-// +build !windows
-
 package processes
 
-import (
-	"bytes"
-	"fmt"
-	"io/ioutil"
-	"os"
-	"os/exec"
-	"path/filepath"
-	"runtime"
-	"strconv"
-	"syscall"
-
-	"github.com/influxdata/telegraf"
-	"github.com/influxdata/telegraf/plugins/inputs"
-	"github.com/influxdata/telegraf/plugins/inputs/linux_sysctl_fs"
-)
-
-type Processes struct {
-	execPS       func() ([]byte, error)
-	readProcFile func(filename string) ([]byte, error)
-
-	Log telegraf.Logger
-
-	forcePS   bool
-	forceProc bool
-}
-
 func (p *Processes) Description() string {
 	return "Get the number of processes and group them by status"
 }
 
 func (p *Processes) SampleConfig() string { return "" }
-
-func (p *Processes) Gather(acc telegraf.Accumulator) error {
-	// Get an empty map of metric fields
-	fields := getEmptyFields()
-
-	// Decide if we will use 'ps' to get stats (use procfs otherwise)
-	usePS := true
-	if runtime.GOOS == "linux" {
-		usePS = false
-	}
-	if p.forcePS {
-		usePS = true
-	} else if p.forceProc {
-		usePS = false
-	}
-
-	// Gather stats from 'ps' or procfs
-	if usePS {
-		if err := p.gatherFromPS(fields); err != nil {
-			return err
-		}
-	} else {
-		if err := p.gatherFromProc(fields); err != nil {
-			return err
-		}
-	}
-
-	acc.AddGauge("processes", fields, nil)
-	return nil
-}
-
-// Gets empty fields of metrics based on the OS
-func getEmptyFields() map[string]interface{} {
-	fields := map[string]interface{}{
-		"blocked":  int64(0),
-		"zombies":  int64(0),
-		"stopped":  int64(0),
-		"running":  int64(0),
-		"sleeping": int64(0),
-		"total":    int64(0),
-		"unknown":  int64(0),
-	}
-	switch runtime.GOOS {
-	case "freebsd":
-		fields["idle"] = int64(0)
-		fields["wait"] = int64(0)
-	case "darwin":
-		fields["idle"] = int64(0)
-	case "openbsd":
-		fields["idle"] = int64(0)
-	case "linux":
-		fields["dead"] = int64(0)
-		fields["paging"] = int64(0)
-		fields["total_threads"] = int64(0)
-		fields["idle"] = int64(0)
-	}
-	return fields
-}
-
-// exec `ps` to get all process states
-func (p *Processes) gatherFromPS(fields map[string]interface{}) error {
-	out, err := p.execPS()
-	if err != nil {
-		return err
-	}
-
-	for i, status := range bytes.Fields(out) {
-		if i == 0 && string(status) == "STAT" {
-			// This is a header, skip it
-			continue
-		}
-		switch status[0] {
-		case 'W':
-			fields["wait"] = fields["wait"].(int64) + int64(1)
-		case 'U', 'D', 'L':
-			// Also known as uninterruptible sleep or disk sleep
-			fields["blocked"] = fields["blocked"].(int64) + int64(1)
-		case 'Z':
-			fields["zombies"] = fields["zombies"].(int64) + int64(1)
-		case 'X':
-			fields["dead"] = fields["dead"].(int64) + int64(1)
-		case 'T':
-			fields["stopped"] = fields["stopped"].(int64) + int64(1)
-		case 'R':
-			fields["running"] = fields["running"].(int64) + int64(1)
-		case 'S':
-			fields["sleeping"] = fields["sleeping"].(int64) + int64(1)
-		case 'I':
-			fields["idle"] = fields["idle"].(int64) + int64(1)
-		case '?':
-			fields["unknown"] = fields["unknown"].(int64) + int64(1)
-		default:
-			p.Log.Infof("Unknown state %q from ps", string(status[0]))
-		}
-		fields["total"] = fields["total"].(int64) + int64(1)
-	}
-	return nil
-}
-
-// get process states from /proc/(pid)/stat files
-func (p *Processes) gatherFromProc(fields map[string]interface{}) error {
-	filenames, err := filepath.Glob(linux_sysctl_fs.GetHostProc() + "/[0-9]*/stat")
-
-	if err != nil {
-		return err
-	}
-
-	for _, filename := range filenames {
-		_, err := os.Stat(filename)
-		data, err := p.readProcFile(filename)
-		if err != nil {
-			return err
-		}
-		if data == nil {
-			continue
-		}
-
-		// Parse out data after (<cmd name>)
-		i := bytes.LastIndex(data, []byte(")"))
-		if i == -1 {
-			continue
-		}
-		data = data[i+2:]
-
-		stats := bytes.Fields(data)
-		if len(stats) < 3 {
-			return fmt.Errorf("Something is terribly wrong with %s", filename)
-		}
-		switch stats[0][0] {
-		case 'R':
-			fields["running"] = fields["running"].(int64) + int64(1)
-		case 'S':
-			fields["sleeping"] = fields["sleeping"].(int64) + int64(1)
-		case 'D':
-			fields["blocked"] = fields["blocked"].(int64) + int64(1)
-		case 'Z':
-			fields["zombies"] = fields["zombies"].(int64) + int64(1)
-		case 'X':
-			fields["dead"] = fields["dead"].(int64) + int64(1)
-		case 'T', 't':
-			fields["stopped"] = fields["stopped"].(int64) + int64(1)
-		case 'W':
-			fields["paging"] = fields["paging"].(int64) + int64(1)
-		case 'I':
-			fields["idle"] = fields["idle"].(int64) + int64(1)
-		case 'P':
-			if _, ok := fields["parked"]; ok {
-				fields["parked"] = fields["parked"].(int64) + int64(1)
-			}
-			fields["parked"] = int64(1)
-		default:
-			p.Log.Infof("Unknown state %q in file %q", string(stats[0][0]), filename)
-		}
-		fields["total"] = fields["total"].(int64) + int64(1)
-
-		threads, err := strconv.Atoi(string(stats[17]))
-		if err != nil {
-			p.Log.Infof("Error parsing thread count: %s", err.Error())
-			continue
-		}
-		fields["total_threads"] = fields["total_threads"].(int64) + int64(threads)
-	}
-	return nil
-}
-
-func readProcFile(filename string) ([]byte, error) {
-	data, err := ioutil.ReadFile(filename)
-	if err != nil {
-		if os.IsNotExist(err) {
-			return nil, nil
-		}
-
-		// Reading from /proc/<PID> fails with ESRCH if the process has
-		// been terminated between open() and read().
-		if perr, ok := err.(*os.PathError); ok && perr.Err == syscall.ESRCH {
-			return nil, nil
-		}
-
-		return nil, err
-	}
-
-	return data, nil
-}
-
-func execPS() ([]byte, error) {
-	bin, err := exec.LookPath("ps")
-	if err != nil {
-		return nil, err
-	}
-
-	out, err := exec.Command(bin, "axo", "state").Output()
-	if err != nil {
-		return nil, err
-	}
-
-	return out, err
-}
-
-func init() {
-	inputs.Add("processes", func() telegraf.Input {
-		return &Processes{
-			execPS:       execPS,
-			readProcFile: readProcFile,
-		}
-	})
-}