feat: add file and crontab collector for node exporter

inputs/node_exporter/collector/collector_darwin.go

@@ -10,4 +10,6 @@ func paramsInit(params map[string]string) {
 	runitCollectorInit(params)
 	supervisordCollectorInit(params)
 	textFileCollectorInit(params)
+	fileCollectorInit(params)
+	crontabCollectorInit(params)
 }

inputs/node_exporter/collector/collector_linux.go

@@ -27,5 +27,6 @@ func paramsInit(params map[string]string) {
 	textFileCollectorInit(params)
 	vmStatCollectorInit(params)
 	wifiCollectorInit(params)
-
+	fileCollectorInit(params)
+	crontabCollectorInit(params)
 }

inputs/node_exporter/collector/collector_windows.go

@@ -6,4 +6,6 @@ func paramsInit(params map[string]string) {
 	runitCollectorInit(params)
 	supervisordCollectorInit(params)
 	textFileCollectorInit(params)
+	fileCollectorInit(params)
+	crontabCollectorInit(params)
 }

inputs/node_exporter/collector/crontab.go

@@ -0,0 +1,98 @@
+package collector
+
+import (
+	"crypto/md5"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+var (
+	crontabDir = new(string)
+	// kingpin.Flag("collector.crontab.dir", "crontab监听目录").Default("/var/spool/cron/crontabs/").String()
+	crontabMap = make(map[string]string)
+)
+
+type crontabCollector struct {
+	cronNotify *prometheus.Desc
+}
+
+func init() {
+	registerCollector("crontab", defaultDisabled, NewCrontabCollector)
+}
+
+func NewCrontabCollector() (Collector, error) {
+	c := &crontabCollector{
+		cronNotify: prometheus.NewDesc(
+			prometheus.BuildFQName(namespace, "", "crontab"),
+			"禁停crontab变化",
+			[]string{"user"}, nil,
+		),
+	}
+	fileList, _ := ioutil.ReadDir(*crontabDir)
+
+	for _, file := range fileList {
+		if file.IsDir() {
+			continue
+		}
+		if data, err := c.readFile(path.Join(*crontabDir, file.Name())); err != nil {
+			panic(err.Error())
+		} else {
+			crontabMap[file.Name()] = fmt.Sprintf("%x", md5.Sum(data))
+		}
+
+	}
+	return c, nil
+}
+
+func (c *crontabCollector) readFile(fileName string) ([]byte, error) {
+	file, err := os.Open(fileName)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	fd, _ := ioutil.ReadAll(file)
+	return fd, nil
+}
+
+func crontabCollectorInit(params map[string]string) {
+	dir, ok := params["collector.crontab.dir"]
+	if !ok {
+		*crontabDir = "/var/spool/cron/crontabs/"
+	} else {
+		*crontabDir = dir
+	}
+}
+
+func (c *crontabCollector) Update(ch chan<- prometheus.Metric) error {
+	fileList, _ := ioutil.ReadDir(*crontabDir)
+	for _, file := range fileList {
+		if file.IsDir() {
+			continue
+		}
+		fileName := file.Name()
+		var v float64 = 0
+		if data, ok := crontabMap[fileName]; !ok {
+			v = 1
+			filedata, _ := c.readFile(path.Join(*crontabDir, fileName))
+			crontabMap[fileName] = fmt.Sprintf("%x", md5.Sum(filedata))
+
+		} else {
+			data1, err := c.readFile(path.Join(*crontabDir, fileName))
+			if err != nil {
+				v = 1
+			}
+			newMd5 := fmt.Sprintf("%x", md5.Sum(data1))
+			if data != newMd5 {
+				v = 1
+				crontabMap[fileName] = newMd5
+			}
+		}
+		ch <- prometheus.MustNewConstMetric(c.cronNotify, prometheus.GaugeValue, v, fileName)
+	}
+	return nil
+}

inputs/node_exporter/collector/file.go

@@ -0,0 +1,82 @@
+package collector
+
+import (
+	"crypto/md5"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"strings"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+var (
+	fileList = new(string)
+	// kingpin.Flag("collector.file.notifylist", "监听文件列表，多个文件以 , 隔开").Default("/etc/passwd,/etc/shadow").String()
+	fileMap = make(map[string]string)
+)
+
+type fileListCollector struct {
+	fileNotify *prometheus.Desc
+}
+
+func init() {
+	registerCollector("filenotify", defaultEnabled, NewFileNotifyCollector)
+}
+
+func NewFileNotifyCollector() (Collector, error) {
+	f := &fileListCollector{
+		fileNotify: prometheus.NewDesc(
+			prometheus.BuildFQName(namespace, "", "filenotify"),
+			"监听对应文件变化",
+			[]string{"file_name"}, nil,
+		),
+	}
+	for _, fileName := range strings.Split(*fileList, ",") {
+		if data, err := f.readFile(fileName); err != nil {
+			panic(err.Error())
+		} else {
+			fileMap[fileName] = fmt.Sprintf("%x", md5.Sum(data))
+		}
+
+	}
+	return f, nil
+}
+
+func (f *fileListCollector) readFile(fileName string) ([]byte, error) {
+	file, err := os.Open(fileName)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	fd, _ := ioutil.ReadAll(file)
+	return fd, nil
+}
+
+func fileCollectorInit(params map[string]string) {
+	files, ok := params["collector.file.notifylist"]
+	if !ok {
+		*fileList = "/etc/passwd,/etc/shadow"
+	} else {
+		*fileList = files
+	}
+}
+
+func (f *fileListCollector) Update(ch chan<- prometheus.Metric) error {
+	for fileName := range fileMap {
+		var v float64 = 0
+		data, err := f.readFile(fileName)
+		if err != nil {
+			v = 1
+		}
+		newMd5 := fmt.Sprintf("%x", md5.Sum(data))
+		if fileMap[fileName] != newMd5 {
+			v = 1
+			fileMap[fileName] = newMd5
+		}
+		ch <- prometheus.MustNewConstMetric(f.fileNotify, prometheus.GaugeValue, v, fileName)
+	}
+
+	return nil
+}