✨ Meta implements TextUnmarshaler

models/meta.go

@@ -3,9 +3,11 @@ package models
 import (
 	"bytes"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"regexp"
 	"strconv"
+	"strings"
 	"time"
 )
 
@@ -16,7 +18,7 @@ type Meta struct {
 
 func (m Meta) MarshalText() ([]byte, error) {
 	if regexp.MustCompile(`\s`).MatchString(m.Key) {
-		return []byte{}, fmt.Errorf("whitespace is now allowed in key: %s", m.Key)
+		return []byte{}, fmt.Errorf("whitespace is not allowed in key: %s", m.Key)
 	}
 	buff := &bytes.Buffer{}
 	buff.WriteRune('@')
@@ -51,3 +53,51 @@ func (m Meta) MarshalText() ([]byte, error) {
 
 	return buff.Bytes(), nil
 }
+
+func (m *Meta) UnmarshalText(in []byte) error {
+	if len(in) == 0 {
+		return errors.New("Unable to Unmarshal empty string")
+	}
+	re := regexp.MustCompile("(?s)^@([^ ]+) (.*)( @end)?$")
+	match := re.FindSubmatch(in)
+	if len(match) == 0 {
+		return fmt.Errorf("Failed to match %s", in)
+	}
+	m.Key = string(match[1])
+	return m.processMeta(match[2])
+}
+
+func (m *Meta) processMeta(in []byte) error {
+	if len(in) == 0 {
+		return errors.New("No value found")
+	}
+	s := strings.TrimSpace(string(in))
+	if len(s) == 0 {
+		return errors.New("No value found")
+	}
+	yesno := regexp.MustCompile("^(y|Y|yes|Yes|YES|n|N|no|No|NO|true|True|TRUE|false|False|FALSE|on|On|ON|off|Off|OFF)$")
+	yes := regexp.MustCompile("^(y|Y|yes|Yes|YES|true|True|TRUE|on|On|ON)$")
+	null := regexp.MustCompile("^(~|null|Null|NULL|none|None|NONE|nil|Nil|NIL)$")
+	var j json.RawMessage
+	if null.MatchString(s) {
+		m.Value = nil
+	} else if yesno.MatchString(s) {
+		if yes.MatchString(s) {
+			m.Value = true
+		} else {
+			m.Value = false
+		}
+	} else if i, err := strconv.Atoi(s); err == nil {
+		m.Value = i
+	} else if f, err := strconv.ParseFloat(s, 64); err == nil {
+		m.Value = f
+	} else if t, err := time.Parse(time.RFC3339, s); err == nil {
+		m.Value = t
+	} else if err := json.Unmarshal(in, &j); err == nil {
+		m.Value = j
+	} else {
+		m.Value = s
+	}
+
+	return nil
+}