koanf reports empty string key after a file gets modified

Open matheusjunior opened this issue 1 year ago • 1 comments

Describe the bug File watcher prints empty string data after file gets modified a couple of times.

To Reproduce

Run the go snippet below
Modify rpc value from config.yaml file
Save config.yaml
Repeat steps 2-3 until issue happens

main.go:

package main

import (
	"fmt"
	"log"
	"time"

	"github.com/knadh/koanf/parsers/yaml"
	"github.com/knadh/koanf/providers/file"
	"github.com/knadh/koanf/v2"
)

func main() {
	k := koanf.New(".")
	provider := file.Provider("config.yaml")
	err := k.Load(provider, yaml.Parser())
	if err != nil {
		panic(err)
	}

	provider.Watch(func(event interface{}, err error) {
		if err != nil {
			log.Printf("watch error: %v", err)
			return
		}

		// Throw away the old config and load a fresh copy.
		log.Println("config changed. Reloading ...")
		k = koanf.New(".")
		err = k.Load(provider, yaml.Parser())
		if err != nil {
			log.Printf("watch error: %v", err)
			return
		}
	})

	go func() {
		for {
			fmt.Println(k.String("rpc"))
			time.Sleep(time.Second)
		}
	}()

	<-make(chan bool)
}

config.yaml:

rpc: "ddf"

Screenshot showing the described behavior: Screenshot from 2024-07-03 18-53-43

Expected behavior Updated rpc value is correctly shown on logs.

Please provide the following information):

OS: Linux 6.5.0-41-generic # 41~22.04.2-Ubuntu SMP PREEMPT_DYNAMIC
Koanf Version: v2.1.1
go version: go version go1.21.6 linux/amd64

Additional context

Jul 03 '24 22:07 matheusjunior

Running the sample code with go run -race main.go suggests that there are data races

go run -race main.go 
xddf
xddf
xddf
2024/07/04 11:32:10 config changed. Reloading ...
==================
WARNING: DATA RACE
Read at 0x00c000112040 by goroutine 9:
  main.main.func2()
      /tmp/test/main.go:39 +0x2e

Previous write at 0x00c000112040 by goroutine 8:
  main.main.func1()
      /tmp/test/main.go:29 +0x38e
  github.com/knadh/koanf/providers/file.(*File).Watch.func1()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:108 +0x4db

Goroutine 9 (running) created at:
  main.main()
      /tmp/test/main.go:37 +0x3a7

Goroutine 8 (running) created at:
  github.com/knadh/koanf/providers/file.(*File).Watch()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:61 +0x40f
  main.main()
      /tmp/test/main.go:21 +0x336
==================
==================
WARNING: DATA RACE
Read at 0x00c00019a0d0 by goroutine 9:
  github.com/knadh/koanf/v2.(*Koanf).Get()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:318 +0x65
  github.com/knadh/koanf/v2.(*Koanf).String()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/getters.go:375 +0x3e
  main.main.func2()
      /tmp/test/main.go:39 +0x47

Previous write at 0x00c00019a0d0 by goroutine 8:
  github.com/knadh/koanf/v2.(*Koanf).merge()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:420 +0x279
  github.com/knadh/koanf/v2.(*Koanf).Load()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:120 +0x1d9
  main.main.func1()
      /tmp/test/main.go:30 +0x3fd
  github.com/knadh/koanf/providers/file.(*File).Watch.func1()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:108 +0x4db

Goroutine 9 (running) created at:
  main.main()
      /tmp/test/main.go:37 +0x3a7

Goroutine 8 (running) created at:
  github.com/knadh/koanf/providers/file.(*File).Watch()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:61 +0x40f
  main.main()
      /tmp/test/main.go:21 +0x336
==================
==================
WARNING: DATA RACE
Read at 0x00c00019a240 by goroutine 9:
  runtime.mapaccess2_faststr()
      /usr/local/go/src/runtime/map_faststr.go:108 +0x0
  github.com/knadh/koanf/v2.(*Koanf).Get()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:318 +0x8d
  github.com/knadh/koanf/v2.(*Koanf).String()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/getters.go:375 +0x3e
  main.main.func2()
      /tmp/test/main.go:39 +0x47

Previous write at 0x00c00019a240 by goroutine 8:
  runtime.mapassign_faststr()
      /usr/local/go/src/runtime/map_faststr.go:203 +0x0
  github.com/knadh/koanf/v2.populateKeyParts()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:509 +0x5e7
  github.com/knadh/koanf/v2.(*Koanf).merge()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:421 +0x2b9
  github.com/knadh/koanf/v2.(*Koanf).Load()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:120 +0x1d9
  main.main.func1()
      /tmp/test/main.go:30 +0x3fd
  github.com/knadh/koanf/providers/file.(*File).Watch.func1()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:108 +0x4db

Goroutine 9 (running) created at:
  main.main()
      /tmp/test/main.go:37 +0x3a7

Goroutine 8 (running) created at:
  github.com/knadh/koanf/providers/file.(*File).Watch()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:61 +0x40f
  main.main()
      /tmp/test/main.go:21 +0x336
==================
==================
WARNING: DATA RACE
Read at 0x00c0001c21e8 by goroutine 9:
  github.com/knadh/koanf/v2.(*Koanf).Get()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:318 +0x9e
  github.com/knadh/koanf/v2.(*Koanf).String()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/getters.go:375 +0x3e
  main.main.func2()
      /tmp/test/main.go:39 +0x47

Previous write at 0x00c0001c21e8 by goroutine 8:
  github.com/knadh/koanf/v2.populateKeyParts()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:509 +0x5f6
  github.com/knadh/koanf/v2.(*Koanf).merge()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:421 +0x2b9
  github.com/knadh/koanf/v2.(*Koanf).Load()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:120 +0x1d9
  main.main.func1()
      /tmp/test/main.go:30 +0x3fd
  github.com/knadh/koanf/providers/file.(*File).Watch.func1()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:108 +0x4db

Goroutine 9 (running) created at:
  main.main()
      /tmp/test/main.go:37 +0x3a7

Goroutine 8 (running) created at:
  github.com/knadh/koanf/providers/file.(*File).Watch()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:61 +0x40f
  main.main()
      /tmp/test/main.go:21 +0x336
==================
==================
WARNING: DATA RACE
Read at 0x00c00019a0c0 by goroutine 9:
  github.com/knadh/koanf/v2.(*Koanf).Get()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:322 +0xee
  github.com/knadh/koanf/v2.(*Koanf).String()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/getters.go:375 +0x3e
  main.main.func2()
      /tmp/test/main.go:39 +0x47

Previous write at 0x00c00019a0c0 by goroutine 8:
  github.com/knadh/koanf/v2.NewWithConf()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:80 +0x28e
  github.com/knadh/koanf/v2.New()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:71 +0x254
  main.main.func1()
      /tmp/test/main.go:29 +0x382
  github.com/knadh/koanf/providers/file.(*File).Watch.func1()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:108 +0x4db

Goroutine 9 (running) created at:
  main.main()
      /tmp/test/main.go:37 +0x3a7

Goroutine 8 (running) created at:
  github.com/knadh/koanf/providers/file.(*File).Watch()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:61 +0x40f
  main.main()
      /tmp/test/main.go:21 +0x336
==================
==================
WARNING: DATA RACE
Read at 0x00c000016130 by goroutine 9:
  github.com/knadh/koanf/maps.Search()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/maps.go:216 +0x47
  github.com/knadh/koanf/v2.(*Koanf).Get()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:322 +0x10d
  github.com/knadh/koanf/v2.(*Koanf).String()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/getters.go:375 +0x3e
  main.main.func2()
      /tmp/test/main.go:39 +0x47

Previous write at 0x00c000016130 by goroutine 8:
  runtime.slicecopy()
      /usr/local/go/src/runtime/slice.go:325 +0x0
  github.com/knadh/koanf/v2.populateKeyParts()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:510 +0x694
  github.com/knadh/koanf/v2.(*Koanf).merge()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:421 +0x2b9
  github.com/knadh/koanf/v2.(*Koanf).Load()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:120 +0x1d9
  main.main.func1()
      /tmp/test/main.go:30 +0x3fd
  github.com/knadh/koanf/providers/file.(*File).Watch.func1()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:108 +0x4db

Goroutine 9 (running) created at:
  main.main()
      /tmp/test/main.go:37 +0x3a7

Goroutine 8 (running) created at:
  github.com/knadh/koanf/providers/file.(*File).Watch()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:61 +0x40f
  main.main()
      /tmp/test/main.go:21 +0x336
==================
==================
WARNING: DATA RACE
Read at 0x00c00019a030 by goroutine 9:
  runtime.mapaccess2_faststr()
      /usr/local/go/src/runtime/map_faststr.go:108 +0x0
  github.com/knadh/koanf/maps.Search()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/maps.go:216 +0x67
  github.com/knadh/koanf/v2.(*Koanf).Get()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:322 +0x10d
  github.com/knadh/koanf/v2.(*Koanf).String()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/getters.go:375 +0x3e
  main.main.func2()
      /tmp/test/main.go:39 +0x47

Previous write at 0x00c00019a030 by goroutine 8:
  runtime.mapassign_faststr()
      /usr/local/go/src/runtime/map_faststr.go:203 +0x0
  github.com/knadh/koanf/maps.Merge()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/maps.go:114 +0x253
  github.com/knadh/koanf/v2.(*Koanf).merge()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:416 +0x13c
  github.com/knadh/koanf/v2.(*Koanf).Load()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:120 +0x1d9
  main.main.func1()
      /tmp/test/main.go:30 +0x3fd
  github.com/knadh/koanf/providers/file.(*File).Watch.func1()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:108 +0x4db

Goroutine 9 (running) created at:
  main.main()
      /tmp/test/main.go:37 +0x3a7

Goroutine 8 (running) created at:
  github.com/knadh/koanf/providers/file.(*File).Watch()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:61 +0x40f
  main.main()
      /tmp/test/main.go:21 +0x336
==================
==================
WARNING: DATA RACE
Read at 0x00c0001b42c8 by goroutine 9:
  github.com/knadh/koanf/maps.Search()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/maps.go:216 +0x75
  github.com/knadh/koanf/v2.(*Koanf).Get()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:322 +0x10d
  github.com/knadh/koanf/v2.(*Koanf).String()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/getters.go:375 +0x3e
  main.main.func2()
      /tmp/test/main.go:39 +0x47

Previous write at 0x00c0001b42c8 by goroutine 8:
  github.com/knadh/koanf/maps.Merge()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/maps.go:114 +0x264
  github.com/knadh/koanf/v2.(*Koanf).merge()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:416 +0x13c
  github.com/knadh/koanf/v2.(*Koanf).Load()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/[email protected]/koanf.go:120 +0x1d9
  main.main.func1()
      /tmp/test/main.go:30 +0x3fd
  github.com/knadh/koanf/providers/file.(*File).Watch.func1()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:108 +0x4db

Goroutine 9 (running) created at:
  main.main()
      /tmp/test/main.go:37 +0x3a7

Goroutine 8 (running) created at:
  github.com/knadh/koanf/providers/file.(*File).Watch()
      /home/rhnvrm/go/pkg/mod/github.com/knadh/koanf/providers/[email protected]/file.go:61 +0x40f
  main.main()
      /tmp/test/main.go:21 +0x336
==================

Jul 04 '24 06:07 rhnvrm