Use a “proper” struct for the login form

Similar to the profile form, the login form now parses and validates
itself, with the InputField structs that the templates expect.

I realized that i was doing more work than necessary when parsing fields
fro the profile form because i was repeating the operation and the field
name, so now it is a function of InputField.

This time i needed extra attributes for the login form.  I am not sure
that the Go source code needs to know about HTML attributes, but it was
the easiest way to pass them to the template.

pkg/form.go

@@ -2,18 +2,29 @@ package pkg
 
 import (
 	"context"
+	"net/http"
 	"net/mail"
+	"strings"
 )
 
+type Attribute struct {
+	Key, Val string
+}
+
 type InputField struct {
 	Name       string
 	Label      string
 	Type       string
 	Value      string
 	Required   bool
+	Attributes []*Attribute
 	Errors     []error
 }
 
+func (field *InputField) FillValue(r *http.Request) {
+	field.Value = strings.TrimSpace(r.FormValue(field.Name))
+}
+
 func (field *InputField) Equals(other *InputField) bool {
 	return field.Value == other.Value
 }
@@ -40,6 +51,10 @@ type SelectField struct {
 	Errors   []error
 }
 
+func (field *SelectField) FillValue(r *http.Request) {
+	field.Selected = r.FormValue(field.Name)
+}
+
 func (field *SelectField) HasValidOption() bool {
 	for _, option := range field.Options {
 		if option.Value == field.Selected {

pkg/login.go

@@ -2,6 +2,7 @@ package pkg
 
 import (
 	"context"
+	"errors"
 	"net"
 	"net/http"
 	"time"
@@ -17,17 +18,66 @@ const (
 	defaultRole      = "guest"
 )
 
-type LoginPage struct {
+type loginForm struct {
-	LoginError bool
+	locale   *Locale
-	Email      string
+	Errors   []error
-	Password   string
+	Email    *InputField
+	Password *InputField
+	Valid    bool
 }
 
-type AppUser struct {
+func newLoginForm(locale *Locale) *loginForm {
-	Email    string
+	return &loginForm{
-	LoggedIn bool
+		locale: locale,
-	Role     string
+		Email: &InputField{
-	Language language.Tag
+			Name:     "email",
+			Label:    pgettext("input", "Email", locale),
+			Type:     "email",
+			Required: true,
+			Attributes: []*Attribute{
+				{"autofocus", "autofocus"},
+				{"autocomplete", "username"},
+				{"autocapitalize", "none"},
+			},
+		},
+		Password: &InputField{
+			Name:     "password",
+			Label:    pgettext("input", "Password", locale),
+			Type:     "password",
+			Required: true,
+			Attributes: []*Attribute{
+				{"autocomplete", "current-password"},
+			},
+		},
+	}
+}
+
+func (form *loginForm) Parse(r *http.Request) error {
+	err := r.ParseForm()
+	if err != nil {
+		return err
+	}
+	form.Email.FillValue(r)
+	form.Password.FillValue(r)
+	return nil
+}
+
+func (form *loginForm) Validate() bool {
+	form.Valid = true
+	if form.Email.IsEmpty() {
+		form.AppendInputError(form.Email, errors.New(gettext("Email can not be empty.", form.locale)))
+	} else if !form.Email.HasValidEmail() {
+		form.AppendInputError(form.Email, errors.New(gettext("This value is not a valid email. It should be like name@domain.com.", form.locale)))
+	}
+	if form.Password.IsEmpty() {
+		form.AppendInputError(form.Password, errors.New(gettext("Password can not be empty.", form.locale)))
+	}
+	return form.Valid
+}
+
+func (form *loginForm) AppendInputError(field *InputField, err error) {
+	field.Errors = append(field.Errors, err)
+	form.Valid = false
 }
 
 func LoginHandler() http.Handler {
@@ -37,25 +87,28 @@ func LoginHandler() http.Handler {
 			http.Redirect(w, r, "/", http.StatusSeeOther)
 			return
 		}
-		r.ParseForm()
+		locale := getLocale(r)
-		page := LoginPage{
+		form := newLoginForm(locale)
-			Email:    r.FormValue("email"),
-			Password: r.FormValue("password"),
-		}
 		if r.Method == "POST" {
+			if err := form.Parse(r); err != nil {
+				http.Error(w, err.Error(), http.StatusBadRequest)
+				return
+			}
+			if form.Validate() {
 				conn := getConn(r)
-			cookie := conn.MustGetText(r.Context(), "", "select login($1, $2, $3)", page.Email, page.Password, remoteAddr(r))
+				cookie := conn.MustGetText(r.Context(), "", "select login($1, $2, $3)", form.Email.Value, form.Password.Value, remoteAddr(r))
 				if cookie != "" {
 					setSessionCookie(w, cookie)
 					http.Redirect(w, r, "/", http.StatusSeeOther)
 					return
 				}
+				form.Errors = append(form.Errors, errors.New(gettext("Invalid user or password.", locale)))
 				w.WriteHeader(http.StatusUnauthorized)
-			page.LoginError = true
 			} else {
-			w.WriteHeader(http.StatusOK)
+				w.WriteHeader(http.StatusUnprocessableEntity)
 			}
-		mustRenderWebTemplate(w, r, "login.gohtml", page)
+		}
+		mustRenderWebTemplate(w, r, "login.gohtml", form)
 	})
 }
 
@@ -91,6 +144,13 @@ func createSessionCookie(value string, duration time.Duration) *http.Cookie {
 	}
 }
 
+type AppUser struct {
+	Email    string
+	LoggedIn bool
+	Role     string
+	Language language.Tag
+}
+
 func CheckLogin(db *Db, next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		var ctx = r.Context()

pkg/profile.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"errors"
 	"net/http"
-	"strings"
 )
 
 type LanguageOption struct {
@@ -13,6 +12,7 @@ type LanguageOption struct {
 }
 
 type profileForm struct {
+	locale          *Locale
 	Name            *InputField
 	Email           *InputField
 	Password        *InputField
@@ -25,6 +25,7 @@ func newProfileForm(ctx context.Context, conn *Conn, locale *Locale) *profileFor
 	automaticOption := pgettext("language option", "Automatic", locale)
 	languages := MustGetOptions(ctx, conn, "select 'und', $1 union all select lang_tag, endonym from language where selectable", automaticOption)
 	return &profileForm{
+		locale: locale,
 		Name: &InputField{
 			Name:     "name",
 			Label:    pgettext("input", "User name", locale),
@@ -59,29 +60,29 @@ func (form *profileForm) Parse(r *http.Request) error {
 	if err := r.ParseForm(); err != nil {
 		return err
 	}
-	form.Email.Value = strings.TrimSpace(r.FormValue("email"))
+	form.Email.FillValue(r)
-	form.Name.Value = strings.TrimSpace(r.FormValue("name"))
+	form.Name.FillValue(r)
-	form.Password.Value = strings.TrimSpace(r.FormValue("password"))
+	form.Password.FillValue(r)
-	form.PasswordConfirm.Value = strings.TrimSpace(r.FormValue("password_confirm"))
+	form.PasswordConfirm.FillValue(r)
-	form.Language.Selected = r.FormValue("language")
+	form.Language.FillValue(r)
 	return nil
 }
 
-func (form *profileForm) Validate(locale *Locale) bool {
+func (form *profileForm) Validate() bool {
 	form.Valid = true
 	if form.Email.IsEmpty() {
-		form.AppendInputError(form.Email, errors.New(gettext("Email can not be empty.", locale)))
+		form.AppendInputError(form.Email, errors.New(gettext("Email can not be empty.", form.locale)))
 	} else if !form.Email.HasValidEmail() {
-		form.AppendInputError(form.Email, errors.New(gettext("This value is not a valid email. It should be like name@domain.com.", locale)))
+		form.AppendInputError(form.Email, errors.New(gettext("This value is not a valid email. It should be like name@domain.com.", form.locale)))
 	}
 	if form.Name.IsEmpty() {
-		form.AppendInputError(form.Name, errors.New(gettext("Name can not be empty.", locale)))
+		form.AppendInputError(form.Name, errors.New(gettext("Name can not be empty.", form.locale)))
 	}
 	if !form.PasswordConfirm.Equals(form.Password) {
-		form.AppendInputError(form.PasswordConfirm, errors.New(gettext("Confirmation does not match password.", locale)))
+		form.AppendInputError(form.PasswordConfirm, errors.New(gettext("Confirmation does not match password.", form.locale)))
 	}
 	if !form.Language.HasValidOption() {
-		form.AppendSelectError(form.Language, errors.New(gettext("Selected language is not valid.", locale)))
+		form.AppendSelectError(form.Language, errors.New(gettext("Selected language is not valid.", form.locale)))
 	}
 	return form.Valid
 }
@@ -107,7 +108,7 @@ func ProfileHandler() http.Handler {
 				http.Error(w, err.Error(), http.StatusBadRequest)
 				return
 			}
-			if ok := form.Validate(locale); ok {
+			if ok := form.Validate(); ok {
 				//goland:noinspection SqlWithoutWhere
 				cookie := conn.MustGetText(r.Context(), "", "update user_profile set name = $1, email = $2, lang_tag = $3 returning build_cookie()", form.Name.Value, form.Email.Value, form.Language.Selected)
 				setSessionCookie(w, cookie)

po/ca.po

@@ -8,7 +8,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: numerus\n"
 "Report-Msgid-Bugs-To: jordi@tandem.blog\n"
-"POT-Creation-Date: 2023-02-01 10:11+0100\n"
+"POT-Creation-Date: 2023-02-01 10:52+0100\n"
 "PO-Revision-Date: 2023-01-18 17:08+0100\n"
 "Last-Translator: jordi fita mas <jordi@tandem.blog>\n"
 "Language-Team: Catalan <ca@dodds.net>\n"
@@ -47,27 +47,12 @@ msgctxt "nav"
 msgid "Contacts"
 msgstr "Contactes"
 
-#: web/template/login.gohtml:2 web/template/login.gohtml:13
+#: web/template/login.gohtml:2 web/template/login.gohtml:15
 msgctxt "title"
 msgid "Login"
 msgstr "Entrada"
 
-#: web/template/login.gohtml:9
+#: web/template/login.gohtml:19
-msgid "Invalid user or password"
-msgstr "Nom d’usuari o contrasenya incorrectes"
-
-#: web/template/login.gohtml:17 web/template/tax-details.gohtml:27
-#: web/template/contacts-new.gohtml:27 pkg/profile.go:36
-msgctxt "input"
-msgid "Email"
-msgstr "Correu-e"
-
-#: web/template/login.gohtml:22 pkg/profile.go:42
-msgctxt "input"
-msgid "Password"
-msgstr "Contrasenya"
-
-#: web/template/login.gohtml:25
 msgctxt "action"
 msgid "Login"
 msgstr "Entra"
@@ -156,6 +141,12 @@ msgctxt "input"
 msgid "Phone"
 msgstr "Telèfon"
 
+#: web/template/tax-details.gohtml:27 web/template/contacts-new.gohtml:27
+#: pkg/login.go:34 pkg/profile.go:37
+msgctxt "input"
+msgid "Email"
+msgstr "Correu-e"
+
 #: web/template/tax-details.gohtml:31 web/template/contacts-new.gohtml:31
 msgctxt "input"
 msgid "Web"
@@ -230,43 +221,56 @@ msgctxt "title"
 msgid "New Contact"
 msgstr "Nou contacte"
 
+#: pkg/login.go:45 pkg/profile.go:43
+msgctxt "input"
+msgid "Password"
+msgstr "Contrasenya"
+
+#: pkg/login.go:68 pkg/profile.go:74
+msgid "Email can not be empty."
+msgstr "No podeu deixar el correu-e en blanc."
+
+#: pkg/login.go:70 pkg/profile.go:76
+msgid "This value is not a valid email. It should be like name@domain.com."
+msgstr "Aquest valor no és un correu-e vàlid. Hauria de ser similar a nom@domini.cat."
+
+#: pkg/login.go:73
+msgid "Password can not be empty."
+msgstr "No podeu deixar la contrasenya en blanc."
+
+#: pkg/login.go:105
+msgid "Invalid user or password."
+msgstr "Nom d’usuari o contrasenya incorrectes."
+
 #: pkg/profile.go:25
 msgctxt "language option"
 msgid "Automatic"
 msgstr "Automàtic"
 
-#: pkg/profile.go:30
+#: pkg/profile.go:31
 msgctxt "input"
 msgid "User name"
 msgstr "Nom d’usuari"
 
-#: pkg/profile.go:47
+#: pkg/profile.go:48
 msgctxt "input"
 msgid "Password Confirmation"
 msgstr "Confirmació contrasenya"
 
-#: pkg/profile.go:52
+#: pkg/profile.go:53
 msgctxt "input"
 msgid "Language"
 msgstr "Idioma"
 
-#: pkg/profile.go:73
+#: pkg/profile.go:79
-msgid "Email can not be empty."
-msgstr "No podeu deixar el correu-e en blanc."
-
-#: pkg/profile.go:75
-msgid "This value is not a valid email. It should be like name@domain.com."
-msgstr "Aquest valor no és un correu-e vàlid. Hauria de ser similar a nom@domini.cat."
-
-#: pkg/profile.go:78
 msgid "Name can not be empty."
 msgstr "No podeu deixar el nom en blanc."
 
-#: pkg/profile.go:81
+#: pkg/profile.go:82
 msgid "Confirmation does not match password."
 msgstr "La confirmació no és igual a la contrasenya."
 
-#: pkg/profile.go:84
+#: pkg/profile.go:85
 msgid "Selected language is not valid."
 msgstr "Heu seleccionat un idioma que no és vàlid."
 

po/es.po

@@ -7,7 +7,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: numerus\n"
 "Report-Msgid-Bugs-To: jordi@tandem.blog\n"
-"POT-Creation-Date: 2023-02-01 10:11+0100\n"
+"POT-Creation-Date: 2023-02-01 10:52+0100\n"
 "PO-Revision-Date: 2023-01-18 17:45+0100\n"
 "Last-Translator: jordi fita mas <jordi@tandem.blog>\n"
 "Language-Team: Spanish <es@tp.org.es>\n"
@@ -47,27 +47,12 @@ msgctxt "nav"
 msgid "Contacts"
 msgstr "Contactos"
 
-#: web/template/login.gohtml:2 web/template/login.gohtml:13
+#: web/template/login.gohtml:2 web/template/login.gohtml:15
 msgctxt "title"
 msgid "Login"
 msgstr "Entrada"
 
-#: web/template/login.gohtml:9
+#: web/template/login.gohtml:19
-msgid "Invalid user or password"
-msgstr "Nombre de usuario o contraseña inválido"
-
-#: web/template/login.gohtml:17 web/template/tax-details.gohtml:27
-#: web/template/contacts-new.gohtml:27 pkg/profile.go:36
-msgctxt "input"
-msgid "Email"
-msgstr "Correo-e"
-
-#: web/template/login.gohtml:22 pkg/profile.go:42
-msgctxt "input"
-msgid "Password"
-msgstr "Contraseña"
-
-#: web/template/login.gohtml:25
 msgctxt "action"
 msgid "Login"
 msgstr "Entrar"
@@ -156,6 +141,12 @@ msgctxt "input"
 msgid "Phone"
 msgstr "Teléfono"
 
+#: web/template/tax-details.gohtml:27 web/template/contacts-new.gohtml:27
+#: pkg/login.go:34 pkg/profile.go:37
+msgctxt "input"
+msgid "Email"
+msgstr "Correo-e"
+
 #: web/template/tax-details.gohtml:31 web/template/contacts-new.gohtml:31
 msgctxt "input"
 msgid "Web"
@@ -230,43 +221,56 @@ msgctxt "title"
 msgid "New Contact"
 msgstr "Nuevo contacto"
 
+#: pkg/login.go:45 pkg/profile.go:43
+msgctxt "input"
+msgid "Password"
+msgstr "Contraseña"
+
+#: pkg/login.go:68 pkg/profile.go:74
+msgid "Email can not be empty."
+msgstr "No podéis dejar el correo-e en blanco."
+
+#: pkg/login.go:70 pkg/profile.go:76
+msgid "This value is not a valid email. It should be like name@domain.com."
+msgstr "Este valor no es un correo-e válido. Tiene que ser parecido a nombre@dominio.es."
+
+#: pkg/login.go:73
+msgid "Password can not be empty."
+msgstr "No podéis dejar la contaseña en blanco."
+
+#: pkg/login.go:105
+msgid "Invalid user or password."
+msgstr "Nombre de usuario o contraseña inválido."
+
 #: pkg/profile.go:25
 msgctxt "language option"
 msgid "Automatic"
 msgstr "Automático"
 
-#: pkg/profile.go:30
+#: pkg/profile.go:31
 msgctxt "input"
 msgid "User name"
 msgstr "Nombre de usuario"
 
-#: pkg/profile.go:47
+#: pkg/profile.go:48
 msgctxt "input"
 msgid "Password Confirmation"
 msgstr "Confirmación contrasenya"
 
-#: pkg/profile.go:52
+#: pkg/profile.go:53
 msgctxt "input"
 msgid "Language"
 msgstr "Idioma"
 
-#: pkg/profile.go:73
+#: pkg/profile.go:79
-msgid "Email can not be empty."
-msgstr "No podéis dejar el correo-e en blanco."
-
-#: pkg/profile.go:75
-msgid "This value is not a valid email. It should be like name@domain.com."
-msgstr "Este valor no es un correo-e válido. Tiene que ser parecido a nombre@dominio.es."
-
-#: pkg/profile.go:78
 msgid "Name can not be empty."
 msgstr "No podéis dejar el nombre en blanco."
 
-#: pkg/profile.go:81
+#: pkg/profile.go:82
 msgid "Confirmation does not match password."
 msgstr "La confirmación no corresponde con la contraseña."
 
-#: pkg/profile.go:84
+#: pkg/profile.go:85
 msgid "Selected language is not valid."
 msgstr "Habéis escogido un idioma que no es válido."
 

web/template/form.gohtml

@@ -1,15 +1,16 @@
 {{ define "input-field" -}}
     <div class="input {{ if .Errors }}has-errors{{ end }}">
         <input type="{{ .Type }}" name="{{ .Name }}" id="{{ .Name }}-field"
+        {{- range $attribute := .Attributes }} {{$attribute.Key}}="{{$attribute.Val}}" {{ end -}}
         {{ if .Required }}required="required"{{ end }} value="{{ .Value }}" placeholder="{{ .Label }}">
         <label for="{{ .Name }}-field">{{ .Label }}</label>
-        {{ if .Errors }}
+        {{- if .Errors }}
             <ul>
                 {{- range $error := .Errors }}
                     <li>{{ . }}</li>
                 {{- end }}
             </ul>
-        {{ end }}
+        {{- end }}
     </div>
 {{- end }}
 

web/template/login.gohtml

@@ -4,24 +4,18 @@
 
 {{ define "content" }}
     <h1><img src="/static/numerus.svg" alt="Numerus" width="620" height="77"></h1>
-	{{ if .LoginError -}}
+    {{ if .Errors -}}
         <div class="error" role="alert">
-		<p>{{( gettext "Invalid user or password" )}}</p>
+            {{ range $error := .Errors -}}
+                <p>{{ $error }}</p>
+            {{- end }}
         </div>
     {{- end }}
     <section id="login">
         <h2>{{( pgettext "Login" "title" )}}</h2>
         <form method="POST" action="/login">
-			<div class="input">
+            {{ template "input-field" .Email }}
-				<input id="user_email" type="email" required autofocus name="email" autocapitalize="none" value="{{ .Email }}" placeholder="{{( pgettext "Email" "input" )}}">
+            {{ template "input-field" .Password }}
-				<label for="user_email">{{( pgettext "Email" "input" )}}</label>
-			</div>
-
-			<div class="input">
-				<input id="user_password" type="password" required name="password" autocomplete="current-password" value="{{ .Password }}" placeholder="{{( pgettext "Password" "input" )}}">
-				<label for="user_password">{{( pgettext "Password" "input" )}}</label>
-			</div>
-
             <button type="submit">{{( pgettext "Login" "action" )}}</button>
         </form>
     </section>