[BUG] config.Scan does not scan duration types for yaml

[belljustin]

config.Scan does not scan duration types for yaml.

1. What are you trying to do?
   I have a struct that contains a time.Duration. I am trying to use config to Scan a yaml file into this struct.
2. What did you expect to happen?
   I expect when using a value such as "1000s" it will create will fill the struct with a 1000 * time.Second. If I use config.Get("duration").Duration(0), I get my expected result.
3. What happens instead?
   When using config.Scan, I get the zero value.

How to reproduce the bug:

Yaml:

duration: 1000s

Go:

package main

import (
	"fmt"
	"time"

	"github.com/micro/go-micro/v2/config"
)

type Config struct {
	Duration time.Duration
}

func main() {
	config.LoadFile("config.yaml")
	fmt.Println(config.Get("duration").Duration(0))

	var conf Config
	config.Scan(&conf)
	fmt.Println(conf)
}

Output:

16m40s
{Duration: 0s}

Environment:
go version go1.14 darwin/amd64

GO111MODULE=""
GOARCH="amd64"
GOBIN=""
GOCACHE="/Users/jbell/Library/Caches/go-build"
GOENV="/Users/jbell/Library/Application Support/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOINSECURE=""
GONOPROXY=""
GONOSUMDB=""
GOOS="darwin"
GOPATH="/Users/jbell/go"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/Users/jbell/.go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/Users/jbell/.go/pkg/tool/darwin_amd64"
GCCGO="gccgo"
AR="ar"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD="/Users/jbell/go/src/github.com/belljustin/scratch/go.mod"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/9f/w1d7k0d97mz1y7fc9cgpl8100000gp/T/go-build458731707=/tmp/go-build -gno-record-gcc-switches -fno-common"

[kaisawind]

#1749 json: cannot unmarshal string into Go struct field Config of type time.Duration.

[ShaileshSurya]

Is this bug still open? I am a first-time contributor can I take this?

[kesslerdev]

It's works with

package config

import (
	"time"

	str2duration "github.com/xhit/go-str2duration"
)

type Duration time.Duration

type Config struct {
	Loop  Duration `json:"loop"`
}

// UnmarshalText implements the text unmarshaller method
func (x *Duration) UnmarshalText(text []byte) error {
	name := string(text)
	tmp, err := str2duration.Str2Duration(name)
	if err != nil {
		return err
	}
	*x = Duration(tmp)
	return nil
}

[belljustin]

This is the same issue as the one linked by @kaisawind . Closing this in favour of that one.