node_exporter/collector/textfile.go

241 lines
6.2 KiB
Go

// Copyright 2015 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// +build !notextfile
package collector
import (
"fmt"
"io/ioutil"
"os"
"path/filepath"
"sort"
"strings"
"sync"
"time"
"github.com/prometheus/client_golang/prometheus"
dto "github.com/prometheus/client_model/go"
"github.com/prometheus/common/expfmt"
"github.com/prometheus/common/log"
kingpin "gopkg.in/alecthomas/kingpin.v2"
)
var (
textFileDirectory = kingpin.Flag("collector.textfile.directory", "Directory to read text files with metrics from.").Default("").String()
textFileAddOnce sync.Once
mtimeDesc = prometheus.NewDesc(
"node_textfile_mtime",
"Unixtime mtime of textfiles successfully read.",
[]string{"file"},
nil,
)
)
type textFileCollector struct {
path string
// Only set for testing to get predictable output.
mtime *float64
}
func init() {
registerCollector("textfile", defaultEnabled, NewTextFileCollector)
}
// NewTextFileCollector returns a new Collector exposing metrics read from files
// in the given textfile directory.
func NewTextFileCollector() (Collector, error) {
c := &textFileCollector{
path: *textFileDirectory,
}
return c, nil
}
func convertMetricFamily(metricFamily *dto.MetricFamily, ch chan<- prometheus.Metric) {
var valType prometheus.ValueType
var val float64
allLabelNames := map[string]struct{}{}
for _, metric := range metricFamily.Metric {
labels := metric.GetLabel()
for _, label := range labels {
if _, ok := allLabelNames[label.GetName()]; !ok {
allLabelNames[label.GetName()] = struct{}{}
}
}
}
for _, metric := range metricFamily.Metric {
if metric.TimestampMs != nil {
log.Warnf("Ignoring unsupported custom timestamp on textfile collector metric %v", metric)
}
labels := metric.GetLabel()
var names []string
var values []string
for _, label := range labels {
names = append(names, label.GetName())
values = append(values, label.GetValue())
}
for k := range allLabelNames {
present := false
for _, name := range names {
if k == name {
present = true
break
}
}
if present == false {
names = append(names, k)
values = append(values, "")
}
}
metricType := metricFamily.GetType()
switch metricType {
case dto.MetricType_COUNTER:
valType = prometheus.CounterValue
val = metric.Counter.GetValue()
case dto.MetricType_GAUGE:
valType = prometheus.GaugeValue
val = metric.Gauge.GetValue()
case dto.MetricType_UNTYPED:
valType = prometheus.UntypedValue
val = metric.Untyped.GetValue()
case dto.MetricType_SUMMARY:
quantiles := map[float64]float64{}
for _, q := range metric.Summary.Quantile {
quantiles[q.GetQuantile()] = q.GetValue()
}
ch <- prometheus.MustNewConstSummary(
prometheus.NewDesc(
*metricFamily.Name,
metricFamily.GetHelp(),
names, nil,
),
metric.Summary.GetSampleCount(),
metric.Summary.GetSampleSum(),
quantiles, values...,
)
case dto.MetricType_HISTOGRAM:
buckets := map[float64]uint64{}
for _, b := range metric.Histogram.Bucket {
buckets[b.GetUpperBound()] = b.GetCumulativeCount()
}
ch <- prometheus.MustNewConstHistogram(
prometheus.NewDesc(
*metricFamily.Name,
metricFamily.GetHelp(),
names, nil,
),
metric.Histogram.GetSampleCount(),
metric.Histogram.GetSampleSum(),
buckets, values...,
)
default:
panic("unknown metric type")
}
if metricType == dto.MetricType_GAUGE || metricType == dto.MetricType_COUNTER || metricType == dto.MetricType_UNTYPED {
ch <- prometheus.MustNewConstMetric(
prometheus.NewDesc(
*metricFamily.Name,
metricFamily.GetHelp(),
names, nil,
),
valType, val, values...,
)
}
}
}
func (c *textFileCollector) exportMTimes(mtimes map[string]time.Time, ch chan<- prometheus.Metric) {
// Export the mtimes of the successful files.
if len(mtimes) > 0 {
// Sorting is needed for predictable output comparison in tests.
filenames := make([]string, 0, len(mtimes))
for filename := range mtimes {
filenames = append(filenames, filename)
}
sort.Strings(filenames)
for _, filename := range filenames {
mtime := float64(mtimes[filename].UnixNano() / 1e9)
if c.mtime != nil {
mtime = *c.mtime
}
ch <- prometheus.MustNewConstMetric(mtimeDesc, prometheus.GaugeValue, mtime, filename)
}
}
}
// Update implements the Collector interface.
func (c *textFileCollector) Update(ch chan<- prometheus.Metric) error {
error := 0.0
mtimes := map[string]time.Time{}
// Iterate over files and accumulate their metrics.
files, err := ioutil.ReadDir(c.path)
if err != nil && c.path != "" {
log.Errorf("Error reading textfile collector directory %s: %s", c.path, err)
error = 1.0
}
for _, f := range files {
if !strings.HasSuffix(f.Name(), ".prom") {
continue
}
path := filepath.Join(c.path, f.Name())
file, err := os.Open(path)
if err != nil {
log.Errorf("Error opening %s: %v", path, err)
error = 1.0
continue
}
var parser expfmt.TextParser
parsedFamilies, err := parser.TextToMetricFamilies(file)
file.Close()
if err != nil {
log.Errorf("Error parsing %s: %v", path, err)
error = 1.0
continue
}
// Only set this once it has been parsed, so that
// a failure does not appear fresh.
mtimes[f.Name()] = f.ModTime()
for _, mf := range parsedFamilies {
if mf.Help == nil {
help := fmt.Sprintf("Metric read from %s", path)
mf.Help = &help
}
convertMetricFamily(mf, ch)
}
}
c.exportMTimes(mtimes, ch)
// Export if there were errors.
ch <- prometheus.MustNewConstMetric(
prometheus.NewDesc(
"node_textfile_scrape_error",
"1 if there was an error opening or reading a file, 0 otherwise",
nil, nil,
),
prometheus.GaugeValue, error,
)
return nil
}