ch8.5

cmd/web/handlers.go

@@ -6,18 +6,17 @@ import (
 	"fmt"
 	"net/http"
 	"strconv"
-	"strings"
-	"unicode/utf8"
 
 	"gitea.local.lab/Lbenedar/snippetbox/internal/models"
+	"gitea.local.lab/Lbenedar/snippetbox/internal/validator"
 	"github.com/julienschmidt/httprouter"
 )
 
 type snippetCreateForm struct {
-	Title       string
-	Content     string
-	Expires     int
-	FieldErrors map[string]string
+	Title   string
+	Content string
+	Expires int
+	validator.Validator
 }
 
 func (app *application) render(w http.ResponseWriter, status int, page string, data *templateData) {
@@ -102,27 +101,17 @@ func (app *application) snippetCreatePost(w http.ResponseWriter, r *http.Request
 	}
 
 	form := snippetCreateForm{
-		Title:       r.PostForm.Get("title"),
-		Content:     r.PostForm.Get("content"),
-		Expires:     expires,
-		FieldErrors: map[string]string{},
+		Title:   r.PostForm.Get("title"),
+		Content: r.PostForm.Get("content"),
+		Expires: expires,
 	}
 
-	if strings.TrimSpace(form.Title) == "" {
-		form.FieldErrors["title"] = "This field cannot be blank"
-	} else if utf8.RuneCountInString(form.Title) > 100 {
-		form.FieldErrors["title"] = "This field cannot be more than 100 character long"
-	}
+	form.CheckField(validator.NotBlank(form.Title), "title", "This field cannot be blank")
+	form.CheckField(validator.MaxChars(form.Title, 100), "title", "This field cannot be more than 100 character long")
+	form.CheckField(validator.NotBlank(form.Content), "content", "This field cannot be blank")
+	form.CheckField(validator.PermittedInt(form.Expires, 1, 7, 365), "expires", "This field must equal 1, 7 and 365")
 
-	if strings.TrimSpace(form.Content) == "" {
-		form.FieldErrors["content"] = "This field cannot be blank"
-	}
-
-	if form.Expires != 1 && form.Expires != 7 && form.Expires != 365 {
-		form.FieldErrors["expires"] = "This field must equal 1, 7 and 365"
-	}
-
-	if len(form.FieldErrors) > 0 {
+	if !form.Valid() {
 		data := app.newTemplateData(r)
 		data.Form = form
 		app.render(w, http.StatusUnprocessableEntity, "create.tmpl", data)

internal/validator/validator.go

@@ -0,0 +1,46 @@
+package validator
+
+import (
+	"strings"
+	"unicode/utf8"
+)
+
+type Validator struct {
+	FieldErrors map[string]string
+}
+
+func (v *Validator) Valid() bool {
+	return len(v.FieldErrors) == 0
+}
+
+func (v *Validator) AddFieldError(key, message string) {
+	if v.FieldErrors == nil {
+		v.FieldErrors = make(map[string]string)
+	}
+	if _, exist := v.FieldErrors[key]; !exist {
+		v.FieldErrors[key] = message
+	}
+}
+
+func (v *Validator) CheckField(ok bool, key, message string) {
+	if !ok {
+		v.AddFieldError(key, message)
+	}
+}
+
+func NotBlank(value string) bool {
+	return strings.TrimSpace(value) != ""
+}
+
+func MaxChars(value string, n int) bool {
+	return utf8.RuneCountInString(value) <= n
+}
+
+func PermittedInt(value int, permittedValues ...int) bool {
+	for i := range permittedValues {
+		if value == permittedValues[i] {
+			return true
+		}
+	}
+	return false
+}