gokultp/go-envparser

package generator

const tmpl = `
// Code generated by github.com/gokultp/go-envparser. DO NOT EDIT.
package {{ .Package }}

import(
    "os"
    "strconv"
    "strings"
    "github.com/gokultp/go-envparser/pkg/envdecoder"
)

func (t *{{.Name }}) DecodeEnv() error {
    {{range $field := .Fields}} {{template "decoder" $field}}  {{end}}
    return nil
}

{{define "decoder" }}
    {{if (is_builtin .Type) }}

    if {{ varname .Name -}}Str := os.Getenv("{{- .EnvTag -}}"); {{- varname .Name -}}Str != "" {

    {{if or (eq (basetype .Type) "rune") (eq (basetype .Type) "byte")}}
        {{varname .Name -}} := []{{- .Type -}}({{- varname .Name -}}Str)
        {{if .IsArray}}
        t.{{- .Name -}} = {{- varname .Name -}}
        {{else if .IsPointer}}
        t.{{- .Name -}} = &{{- varname .Name -}}[0]
        {{else}}
        t.{{- .Name -}} = {{- varname .Name -}}[0]
        {{end}}
    {{else}}
    {{if .IsArray}}
        {{varname .Name}}Arr := strings.Split({{varname .Name}}Str, ":")
        for _, {{varname .Name}}Str := range {{varname .Name}}Arr{
            {{template "singledecoder" .}}
        }
    {{else}}
    {{template "singledecoder" .}}
    {{end}}
    {{end }}
    }
    {{else}}
    {{varname .Name -}} := {{- .Type -}}{} 
    if err := envdecoder.Decode(&{{- varname .Name -}}); err != nil {
        return fmt.Errorf("type {{ .Type -}} not implemts env Decoder interface, %w", envdecoder.ErrDecoderNotImplemented)
    }
    {{template "populate" .}}
    {{end}}
{{end }}


{{define "singledecoder"}} 
    {{if or (eq (basetype .Type) "int") (eq (basetype .Type) "uint") (eq (basetype .Type) "float") }}
        {{ varname .Name -}}64, err := {{- (parsefunc .Type .Name )}}
        if err != nil {
            return err
        }
        {{varname .Name -}} := {{- .Type -}}({{- varname .Name -}}64)
        {{template "populate" .}}
    {{else if eq (basetype .Type) "bool"}}
        {{ varname .Name -}}, err := {{- (parsefunc .Type .Name )}}
        if err != nil {
            return err
        }
        {{template "populate" .}}
    {{else if eq (basetype .Type) "string" }}
    {{ varname .Name -}} := {{ varname .Name -}}Str
    {{template "populate" .}}    
    {{end}}
{{end}}

{{ define "populate"}}
    {{if .IsPointer}}
        t.{{- .Name -}} = &{{- varname .Name -}}
        {{else if .IsArray}}
        t.{{- .Name -}} = append(t.{{- .Name -}}, {{- varname .Name -}})
        {{else}}
        t.{{- .Name -}} = {{- varname .Name -}}
    {{end}}
{{end}}
`