lets-go:8.4 form repopulation

snippetbox/cmd/web/handlers.go

@@ -56,9 +56,20 @@ func (app *application) snippetView(w http.ResponseWriter, r *http.Request) {
 func (app *application) snippetCreate(w http.ResponseWriter, r *http.Request) {
 	data := app.newTemplateData(r)
 
+	data.Form = snippetCreateForm{
+		Expires: 365,
+	}
+
 	app.render(w, r, http.StatusOK, "create.tmpl", data)
 }
 
+type snippetCreateForm struct {
+	Title       string
+	Content     string
+	Expires     int
+	FieldErrors map[string]string
+}
+
 // snippetCreatePost ...
 func (app *application) snippetCreatePost(w http.ResponseWriter, r *http.Request) {
 	err := r.ParseForm()
@@ -67,37 +78,41 @@ func (app *application) snippetCreatePost(w http.ResponseWriter, r *http.Request
 		return
 	}
 
-	title := r.PostForm.Get("title")
-	content := r.PostForm.Get("content")
-
 	expires, err := strconv.Atoi(r.PostForm.Get("expires"))
 	if err != nil {
 		app.clientError(w, http.StatusBadRequest)
 		return
 	}
 
-	fieldErrors := make(map[string]string)
-
-	if strings.TrimSpace(title) == "" {
-		fieldErrors["title"] = "This field cannot be blank"
-	} else if utf8.RuneCountInString(title) > 100 {
-		fieldErrors["title"] = "This field cannot contain more than 100 characters"
+	form := snippetCreateForm{
+		Title:       r.PostForm.Get("title"),
+		Content:     r.PostForm.Get("content"),
+		Expires:     expires,
+		FieldErrors: map[string]string{},
 	}
 
-	if strings.TrimSpace(content) == "" {
-		fieldErrors["content"] = "This field cannot be blank"
+	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 contain more than 100 characters"
 	}
 
-	if expires != 1 && expires != 7 && expires != 365 {
-		fieldErrors["expires"] = "This field must equal 1, 7 or 365"
+	if strings.TrimSpace(form.Content) == "" {
+		form.FieldErrors["content"] = "This field cannot be blank"
 	}
 
-	if len(fieldErrors) > 0 {
-		fmt.Fprint(w, fieldErrors)
+	if form.Expires != 1 && form.Expires != 7 && form.Expires != 365 {
+		form.FieldErrors["expires"] = "This field must equal 1, 7 or 365"
+	}
+
+	if len(form.FieldErrors) > 0 {
+		data := app.newTemplateData(r)
+		data.Form = form
+		app.render(w, r, http.StatusUnprocessableEntity, "create.tmpl", data)
 		return
 	}
 
-	id, err := app.snippets.Insert(title, content, expires)
+	id, err := app.snippets.Insert(form.Title, form.Content, form.Expires)
 	if err != nil {
 		app.serverError(w, r, err)
 		return

snippetbox/cmd/web/templates.go

@@ -12,6 +12,7 @@ type templateData struct {
 	CurrentYear int
 	Snippet     models.Snippet
 	Snippets    []models.Snippet
+	Form        any
 }
 
 // humanDate ...

snippetbox/ui/html/pages/create.tmpl

@@ -4,17 +4,26 @@
 <form action='/snippet/create' method='POST'>
   <div>
     <label>Title:</label>
-    <input type='text' name='title'>
+    {{with .Form.FieldErrors.title}}
+    <label class='error'>{{.}}</label>
+    {{end}}
+    <input type='text' name='title' value='{{.Form.Title}}'>
   </div>
   <div>
     <label>Content:</label>
+    {{with .Form.FieldErrors.content}}
+    <label class='error'>{{.}}</label>
+    {{end}}
     <textarea name='content'></textarea>
   </div>
   <div>
     <label>Delete in:</label>
-    <input type='radio' name='expires' value='365' checked> One Year
-    <input type='radio' name='expires' value='7'> One Week
-    <input type='radio' name='expires' value='1'> One Day
+    {{with .Form.FieldErrors.expires}}
+    <label class='error'>{{.}}</label>
+    {{end}}
+    <input type='radio' name='expires' value='365' {{if (eq .Form.Expires 365) }}checked{{end}}> One Year
+    <input type='radio' name='expires' value='7' {{if (eq .Form.Expires 7) }}checked{{end}}> One Week
+    <input type='radio' name='expires' value='1' {{if (eq .Form.Expires 1) }}checked{{end}}> One Day
   </div>
   <div>
     <input type='submit' value='Publish Snippet'>