Log permission error and ignore in filecount input (#5483)

plugins/inputs/filecount/README.md

@@ -1,6 +1,6 @@
 # Filecount Input Plugin
 
-Counts files in directories that match certain criteria.
+Reports the number and total size of files in specified directories.
 
 ### Configuration:
 
@@ -8,7 +8,7 @@ Counts files in directories that match certain criteria.
 [[inputs.filecount]]
   ## Directory to gather stats about.
   ##   deprecated in 1.9; use the directories option
-  directory = "/var/cache/apt/archives"
+  # directory = "/var/cache/apt/archives"
 
   ## Directories to gather stats about.
   ## This accept standard unit glob matching rules, but with the addition of
@@ -16,13 +16,13 @@ Counts files in directories that match certain criteria.
   ##   /var/log/**    -> recursively find all directories in /var/log and count files in each directories
   ##   /var/log/*/*   -> find all directories with a parent dir in /var/log and count files in each directories
   ##   /var/log       -> count all files in /var/log and all of its subdirectories
-  directories = ["/var/cache/apt/archives"]
+  directories = ["/var/cache/apt", "/tmp"]
 
   ## Only count files that match the name pattern. Defaults to "*".
-  name = "*.deb"
+  name = "*"
 
   ## Count files in subdirectories. Defaults to true.
-  recursive = false
+  recursive = true
 
   ## Only count regular files. Defaults to true.
   regular_only = true

plugins/inputs/filecount/filecount.go

@@ -1,22 +1,25 @@
 package filecount
 
 import (
+	"log"
 	"os"
 	"path/filepath"
 	"strings"
 	"time"
 
+	"github.com/karrick/godirwalk"
+	"github.com/pkg/errors"
+
 	"github.com/influxdata/telegraf"
 	"github.com/influxdata/telegraf/internal"
 	"github.com/influxdata/telegraf/internal/globpath"
 	"github.com/influxdata/telegraf/plugins/inputs"
-	"github.com/karrick/godirwalk"
 )
 
 const sampleConfig = `
   ## Directory to gather stats about.
   ##   deprecated in 1.9; use the directories option
-  directory = "/var/cache/apt/archives"
+  # directory = "/var/cache/apt/archives"
 
   ## Directories to gather stats about.
   ## This accept standard unit glob matching rules, but with the addition of
@@ -152,6 +155,7 @@ func (fc *FileCount) initFileFilters() {
 func (fc *FileCount) count(acc telegraf.Accumulator, basedir string, glob globpath.GlobPath) {
 	childCount := make(map[string]int64)
 	childSize := make(map[string]int64)
+
 	walkFn := func(path string, de *godirwalk.Dirent) error {
 		if path == basedir {
 			return nil
@@ -178,6 +182,7 @@ func (fc *FileCount) count(acc telegraf.Accumulator, basedir string, glob globpa
 		}
 		return nil
 	}
+
 	postChildrenFn := func(path string, de *godirwalk.Dirent) error {
 		if glob.MatchString(path) {
 			gauge := map[string]interface{}{
@@ -203,6 +208,13 @@ func (fc *FileCount) count(acc telegraf.Accumulator, basedir string, glob globpa
 		Callback:             walkFn,
 		PostChildrenCallback: postChildrenFn,
 		Unsorted:             true,
+		ErrorCallback: func(osPathname string, err error) godirwalk.ErrorAction {
+			if os.IsPermission(errors.Cause(err)) {
+				log.Println("D! [inputs.filecount]", err)
+				return godirwalk.SkipNode
+			}
+			return godirwalk.Halt
+		},
 	})
 	if err != nil {
 		acc.AddError(err)