gokultp/go-envparser

package generator

import (
    "bytes"
    "fmt"
    "go/format"
    "io/ioutil"
    "log"
    "path"
    "regexp"
    "strings"
    "text/template"

    "github.com/gokultp/go-envparser/internal/parser"
)

// GenerateCode executes the template based on parsed struct data
func GenerateCode(typeDef *parser.Type) ([]byte, error) {
    funcMap := getFuncMap()
    tmpl, err := template.New("template").Funcs(funcMap).Parse(tmpl)
    if err != nil {
        return nil, err
    }
    var b bytes.Buffer

    if err := tmpl.Execute(&b, typeDef); err != nil {
        return nil, err
    }
    code := b.Bytes()
    code, err = format.Source(removeEmptyLines(code))
    if err != nil {
        return nil, err
    }
    return code, nil
}

// SaveCode will save the generated code to file
// Filename format Lowecase(<struct name>decoder.go)
func SaveCode(typeDef *parser.Type, code []byte) error {
    fpath := path.Dir(typeDef.FileName)
    fpath = path.Join(fpath, fmt.Sprintf("%sdecoder.go", strings.ToLower(typeDef.Name)))
    return ioutil.WriteFile(fpath, code, 0644)
}

// removeEmptyLines will remove the empty lines generated as part of template execution
func removeEmptyLines(source []byte) []byte {
    reg, err := regexp.Compile(`\n\s*\n`)
    if err != nil {
        log.Fatal(err)
    }
    return reg.ReplaceAll(source, []byte{'\n'})
}