telegraf/plugins/inputs/filestat/filestat.go

186 lines
4.0 KiB
Go

package filestat
import (
"crypto/md5"
"fmt"
"io"
"os"
"path/filepath"
"strings"
"github.com/gobwas/glob"
"github.com/influxdata/telegraf"
"github.com/influxdata/telegraf/plugins/inputs"
)
var sepStr = fmt.Sprintf("%v", string(os.PathSeparator))
const sampleConfig = `
## Files to gather stats about.
## These accept standard unix glob matching rules, but with the addition of
## ** as a "super asterisk". See https://github.com/gobwas/glob.
files = ["/etc/telegraf/telegraf.conf", "/var/log/**.log"]
## If true, read the entire file and calculate an md5 checksum.
md5 = false
`
type FileStat struct {
Md5 bool
Files []string
// maps full file paths to glob obj
globs map[string]glob.Glob
// maps full file paths to their root dir
roots map[string]string
}
func NewFileStat() *FileStat {
return &FileStat{
globs: make(map[string]glob.Glob),
roots: make(map[string]string),
}
}
func (_ *FileStat) Description() string {
return "Read stats about given file(s)"
}
func (_ *FileStat) SampleConfig() string { return sampleConfig }
func (f *FileStat) Gather(acc telegraf.Accumulator) error {
var errS string
var err error
for _, filepath := range f.Files {
// Get the compiled glob object for this filepath
g, ok := f.globs[filepath]
if !ok {
if g, err = glob.Compile(filepath, os.PathSeparator); err != nil {
errS += err.Error() + " "
continue
}
f.globs[filepath] = g
}
// Get the root directory for this filepath
root, ok := f.roots[filepath]
if !ok {
root = findRootDir(filepath)
f.roots[filepath] = root
}
var matches []string
// Do not walk file tree if we don't have to.
if !hasMeta(filepath) {
matches = []string{filepath}
} else {
matches = walkFilePath(f.roots[filepath], f.globs[filepath])
}
for _, file := range matches {
tags := map[string]string{
"file": file,
}
fields := map[string]interface{}{
"exists": int64(0),
}
// Get file stats
fileInfo, err := os.Stat(file)
if os.IsNotExist(err) {
// file doesn't exist, so move on to the next
acc.AddFields("filestat", fields, tags)
continue
}
if err != nil {
errS += err.Error() + " "
continue
}
// file exists and no errors encountered
fields["exists"] = int64(1)
fields["size_bytes"] = fileInfo.Size()
if f.Md5 {
md5, err := getMd5(file)
if err != nil {
errS += err.Error() + " "
} else {
fields["md5_sum"] = md5
}
}
acc.AddFields("filestat", fields, tags)
}
}
if errS != "" {
return fmt.Errorf(errS)
}
return nil
}
// walk the filepath from the given root and return a list of files that match
// the given glob.
func walkFilePath(root string, g glob.Glob) []string {
matchedFiles := []string{}
walkfn := func(path string, _ os.FileInfo, _ error) error {
if g.Match(path) {
matchedFiles = append(matchedFiles, path)
}
return nil
}
filepath.Walk(root, walkfn)
return matchedFiles
}
// Read given file and calculate an md5 hash.
func getMd5(file string) (string, error) {
of, err := os.Open(file)
if err != nil {
return "", err
}
defer of.Close()
hash := md5.New()
_, err = io.Copy(hash, of)
if err != nil {
// fatal error
return "", err
}
return fmt.Sprintf("%x", hash.Sum(nil)), nil
}
// find the root dir of the given path (could include globs).
// ie:
// /var/log/telegraf.conf -> /var/log/
// /home/** -> /home/
// /home/*/** -> /home/
// /lib/share/*/*/**.txt -> /lib/share/
func findRootDir(path string) string {
pathItems := strings.Split(path, sepStr)
outpath := sepStr
for i, item := range pathItems {
if i == len(pathItems)-1 {
break
}
if item == "" {
continue
}
if hasMeta(item) {
break
}
outpath += item + sepStr
}
return outpath
}
// hasMeta reports whether path contains any magic glob characters.
func hasMeta(path string) bool {
return strings.IndexAny(path, "*?[") >= 0
}
func init() {
inputs.Add("filestat", func() telegraf.Input {
return NewFileStat()
})
}