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goviper-go

How to load a list of maps with viper?


I have the following config I want to load with viper:

artist:
  name: The Beatles
  albums:
  - name: The White Album
    year: 1968
  - name: Abbey Road
    year: 1969

I can't work out how to load a list of maps. I guess I need to unmarshal just this key, but this code doesn't work:

type Album struct {
    Name string
    Year int
}

type Artist struct {
    Name string
    Albums []Album
}

var artist Artist
viper.UnmarshalKey("artists", &artist)

What am I missing?


Solution

  • Are you sure key is artists in the yaml? Do you mean to supply artist?

    Working example:

    str := []byte(`artist:
      name: The Beatles
      albums:
      - name: The White Album
        year: 1968
      - name: Abbey Road
        year: 1969
    `)
    
        viper.SetConfigType("yaml")
        viper.ReadConfig(bytes.NewBuffer(str))
    
        var artist Artist
        err := viper.UnmarshalKey("artist", &artist)
    
        fmt.Printf("%v, %#v\n", err, artist)
    

    Output:

    <nil>, main.Artist{Name:"The Beatles", Albums:[]main.Album{main.Album{Name:"The White Album", Year:1968}, main.Album{Name:"Abbey Road", Year:1969}}}