print tables in golang

The standard library has a hidden gem called text/tabwriter which can be used to pretty print a table in the CLI.

The parameters from this blogpost gives quite a pleasant result:

ID      Track   Title                           Disc    Suffix  Bitrate Duration    Size    Album ID
--      -----   -----                           ----    ------  ------- --------    ----    --------
tr-2927 1       Østenfor Sol og vestenfor Maane 1       flac    736Kbps 3m26s       582MB   al-463
tr-2928 2       Ord                             1       flac    516Kbps 17s         972MB   al-463
tr-2929 3       Høyfjeldsbilde                  1       flac    631Kbps 2m15s       869MB   al-463
tr-2930 4       Nattleite                       1       flac    700Kbps 2m11s       516MB   al-463
tr-2931 5       Kveldssang                      1       flac    562Kbps 1m32s       282MB   al-463
tr-2932 6       Naturmystikk                    1       flac    640Kbps 2m55s       666MB   al-463
tr-2933 7       A cappella (Sielens sang)       1       flac    665Kbps 1m26s       893MB   al-463
tr-2934 8       Hiertets vee                    1       flac    682Kbps 3m54s       128MB   al-463
tr-2935 9       Kledt i nattens farger          1       flac    649Kbps 2m51s       522MB   al-463
tr-2936 10      Halling                         1       flac    633Kbps 2m7s        536MB   al-463
tr-2937 11      Utreise                         1       flac    676Kbps 2m56s       833MB   al-463
tr-2938 12      Søfn‐ør paa Alfers Lund         1       flac    654Kbps 2m37s       438MB   al-463
tr-2939 13      Ulvsblakk                       1       flac    732Kbps 6m56s       368MB   al-463

The “underlined” header can be added as follows¹:

func SongsTable() string {
    text := []string{}

    // Header fields
    header := []string{
        "ID",
        "Track",
        "Title",
        "Disc",
        "Suffix",
        "Bitrate",
        "Duration",
        "Size",
        "Album ID"
    }

    // The "---" under each header
    headerLine := []string{}
    for _, i := range header {
        headerLine = append(headerLine, strings.Repeat("-", len(i)))
    }
    text = append(
        text,
        []string{strings.Join(header, "\t"),
        strings.Join(headerLine, "\t")}...,
    )

    // The content of the table
    content := []string{}
    // ...
    // (Append to `content` the rows of the table, with each field tab delimited)
    // ...
    text = append(text, content)

    return strings.Join(text, "\n")
}