renaming plugins -> inputs

plugins/inputs/bcache/bcache.go

@@ -0,0 +1,141 @@
+package bcache
+
+import (
+	"errors"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+
+	"github.com/influxdb/telegraf/plugins/inputs"
+)
+
+type Bcache struct {
+	BcachePath string
+	BcacheDevs []string
+}
+
+var sampleConfig = `
+  # Bcache sets path
+  # If not specified, then default is:
+  # bcachePath = "/sys/fs/bcache"
+  #
+  # By default, telegraf gather stats for all bcache devices
+  # Setting devices will restrict the stats to the specified
+  # bcache devices.
+  # bcacheDevs = ["bcache0", ...]
+`
+
+func (b *Bcache) SampleConfig() string {
+	return sampleConfig
+}
+
+func (b *Bcache) Description() string {
+	return "Read metrics of bcache from stats_total and dirty_data"
+}
+
+func getTags(bdev string) map[string]string {
+	backingDevFile, _ := os.Readlink(bdev)
+	backingDevPath := strings.Split(backingDevFile, "/")
+	backingDev := backingDevPath[len(backingDevPath)-2]
+
+	bcacheDevFile, _ := os.Readlink(bdev + "/dev")
+	bcacheDevPath := strings.Split(bcacheDevFile, "/")
+	bcacheDev := bcacheDevPath[len(bcacheDevPath)-1]
+
+	return map[string]string{"backing_dev": backingDev, "bcache_dev": bcacheDev}
+}
+
+func prettyToBytes(v string) uint64 {
+	var factors = map[string]uint64{
+		"k": 1 << 10,
+		"M": 1 << 20,
+		"G": 1 << 30,
+		"T": 1 << 40,
+		"P": 1 << 50,
+		"E": 1 << 60,
+	}
+	var factor uint64
+	factor = 1
+	prefix := v[len(v)-1 : len(v)]
+	if factors[prefix] != 0 {
+		v = v[:len(v)-1]
+		factor = factors[prefix]
+	}
+	result, _ := strconv.ParseFloat(v, 32)
+	result = result * float64(factor)
+
+	return uint64(result)
+}
+
+func (b *Bcache) gatherBcache(bdev string, acc inputs.Accumulator) error {
+	tags := getTags(bdev)
+	metrics, err := filepath.Glob(bdev + "/stats_total/*")
+	if len(metrics) < 0 {
+		return errors.New("Can't read any stats file")
+	}
+	file, err := ioutil.ReadFile(bdev + "/dirty_data")
+	if err != nil {
+		return err
+	}
+	rawValue := strings.TrimSpace(string(file))
+	value := prettyToBytes(rawValue)
+
+	fields := make(map[string]interface{})
+	fields["dirty_data"] = value
+
+	for _, path := range metrics {
+		key := filepath.Base(path)
+		file, err := ioutil.ReadFile(path)
+		rawValue := strings.TrimSpace(string(file))
+		if err != nil {
+			return err
+		}
+		if key == "bypassed" {
+			value := prettyToBytes(rawValue)
+			fields[key] = value
+		} else {
+			value, _ := strconv.ParseUint(rawValue, 10, 64)
+			fields[key] = value
+		}
+	}
+	acc.AddFields("bcache", fields, tags)
+	return nil
+}
+
+func (b *Bcache) Gather(acc inputs.Accumulator) error {
+	bcacheDevsChecked := make(map[string]bool)
+	var restrictDevs bool
+	if len(b.BcacheDevs) != 0 {
+		restrictDevs = true
+		for _, bcacheDev := range b.BcacheDevs {
+			bcacheDevsChecked[bcacheDev] = true
+		}
+	}
+
+	bcachePath := b.BcachePath
+	if len(bcachePath) == 0 {
+		bcachePath = "/sys/fs/bcache"
+	}
+	bdevs, _ := filepath.Glob(bcachePath + "/*/bdev*")
+	if len(bdevs) < 1 {
+		return errors.New("Can't find any bcache device")
+	}
+	for _, bdev := range bdevs {
+		if restrictDevs {
+			bcacheDev := getTags(bdev)["bcache_dev"]
+			if !bcacheDevsChecked[bcacheDev] {
+				continue
+			}
+		}
+		b.gatherBcache(bdev, acc)
+	}
+	return nil
+}
+
+func init() {
+	inputs.Add("bcache", func() inputs.Input {
+		return &Bcache{}
+	})
+}