Goのテンプレートでカスタム関数を定義するメモ

ただのメモだ。

template.go

package main

import (
    "fmt"
    "os"
    "text/template"
    "time"
)

func isotime(layout string) string {
    now := time.Now()
    return now.Format(layout)
}

func timestamp() string {
    return time.Now().Format("20060102030405")
}

func main() {
    tmplText1 := "Path is: /path/to/{{isotime `20060102030405`}}\n"
    tmplText2 := "Path is: /path/to/{{timestamp}}\n"

    funcMap := template.FuncMap{
        "isotime":   isotime,
        "timestamp": timestamp,
    }

    t1, err := template.New("isotime").Funcs(funcMap).Parse(tmplText1)
    if err != nil {
        fmt.Printf("execution: %s", err)
    }
    err = t1.Execute(os.Stdout, "")
    if err != nil {
        fmt.Printf("execution: %s", err)
    }

    t2, err := template.New("timestamp").Funcs(funcMap).Parse(tmplText2)
    if err != nil {
        fmt.Printf("execution: %s", err)
    }
    err = t2.Execute(os.Stdout, "")
    if err != nil {
        fmt.Printf("execution: %s", err)
    }
}