Fill a template with variables in Go

gen.go

package main

import (
	"encoding/json"
	"io/ioutil"
	"log"
	"os"
	"path/filepath"
	"text/template"
)

func main() {
	err := generate("output/test.go", "test")
	if err != nil {
		log.Fatal(err)
	}

	log.Println("Generated successfully")
}

func generate(file string, name string) error {

	// File paths
	tPath := filepath.Join("template", name+".gen")
	vPath := filepath.Join("template", name+".json")

	// Read the config file
	b, err := ioutil.ReadFile(vPath)
	if err != nil {
		return err
	}

	// Convert json to interface
	var d map[string]interface{}
	err = json.Unmarshal(b, &d)
	if err != nil {
		return err
	}

	// Parse the template
	t, err := template.ParseFiles(tPath)
	if err != nil {
		return err
	}

	// Create the output file
	f, err := os.Create(file)
	if err != nil {
		return err
	}
	defer f.Close()

	// Fills template with variables and writes to file
	err = t.Execute(f, d)
	if err != nil {
		return err
	}

	return nil
}

info.txt

Template:
{
	"table": "note",
	"chair": [
		"walnut",
		"cherry",
		"pine",
	],
	"desk": {
		"drawer":"pen"
	}	
}

Variables:
var (
	table = "{{.table}}"
	chair = "{{index .chair 1}}"
	desk  = "{{.desk.drawer}}"
)

Output:
var (
	table = "note"
	chair = "cherry"
	desk  = "pen"
)