feat: added option to follow symlinks

closes #11

README.md

@@ -25,10 +25,11 @@ Flags:
   -b, --bind-address string    Address to bind to (default "0.0.0.0:9995")
   -c, --config string          config file (default is $HOME/.disk_usage_exporter.yaml)
   -l, --dir-level int          Directory nesting level to show (0 = only selected dir) (default 2)
+  -L, --follow-symlinks        Follow symlinks for files, i.e. show the size of the file to which symlink points to (symlinks to directories are not followed)
   -h, --help                   help for disk_usage_exporter
+  -i, --ignore-dirs strings    Absolute paths to ignore (separated by comma) (default [/proc,/dev,/sys,/run,/var/cache/rsnapshot])
   -m, --mode string            Exposition method - either 'file' or 'http' (default "http")
   -f, --output-file string     Target file to store metrics in (default "./disk-usage-exporter.prom")
-  -i, --ignore-dirs strings    Absolute paths to ignore (separated by comma) (default [/proc,/dev,/sys,/run,/var/cache/rsnapshot])
 ```
 
 ## Example output

cmd/root.go

@@ -29,6 +29,7 @@ and reporting which directories consume what space.`,
 		e := exporter.NewExporter(
 			viper.GetInt("dir-level"),
 			viper.GetString("analyzed-path"),
+			viper.GetBool("follow-symlinks"),
 		)
 		e.SetIgnoreDirPaths(viper.GetStringSlice("ignore-dirs"))
 
@@ -59,6 +60,10 @@ func init() {
 	flags.StringP("analyzed-path", "p", "/", "Path where to analyze disk usage")
 	flags.IntP("dir-level", "l", 2, "Directory nesting level to show (0 = only selected dir)")
 	flags.StringSliceP("ignore-dirs", "i", []string{"/proc", "/dev", "/sys", "/run", "/var/cache/rsnapshot"}, "Absolute paths to ignore (separated by comma)")
+	flags.BoolP(
+		"follow-symlinks", "L", false,
+		"Follow symlinks for files, i.e. show the size of the file to which symlink points to (symlinks to directories are not followed)",
+	)
 
 	viper.BindPFlags(flags)
 }

exporter/exporter.go

@@ -40,19 +40,22 @@ type Exporter struct {
 	ignoreDirPaths map[string]struct{}
 	maxLevel       int
 	path           string
+	followSymlinks bool
 }
 
 // NewExporter creates new Exporter
-func NewExporter(maxLevel int, path string) *Exporter {
+func NewExporter(maxLevel int, path string, followSymlinks bool) *Exporter {
 	return &Exporter{
-		maxLevel: maxLevel,
-		path:     filepath.Clean(path),
+		maxLevel:       maxLevel,
+		path:           filepath.Clean(path),
+		followSymlinks: followSymlinks,
 	}
 }
 
 func (e *Exporter) runAnalysis() {
 	defer debug.FreeOSMemory()
 	analyzer := analyze.CreateAnalyzer()
+	analyzer.SetFollowSymlinks(e.followSymlinks)
 	dir := analyzer.AnalyzeDir(e.path, e.shouldDirBeIgnored, false)
 	dir.UpdateStats(fs.HardLinkedItems{})
 	e.reportItem(dir, 0)

exporter/exporter_test.go

@@ -15,7 +15,7 @@ func TestRunAnalysis(t *testing.T) {
 
 	w := &mockedResponseWriter{}
 
-	e := exporter.NewExporter(2, "test_dir")
+	e := exporter.NewExporter(2, "test_dir", false)
 	e.SetIgnoreDirPaths([]string{"/proc"})
 	e.ServeHTTP(w, &http.Request{
 		Header: make(http.Header),