Server Side form validation 4: check email

go.mod

@@ -7,3 +7,5 @@ require github.com/go-chi/chi/v5 v5.0.14
 require github.com/justinas/nosurf v1.1.1
 
 require github.com/alexedwards/scs/v2 v2.8.0
+
+require github.com/asaskevich/govalidator v0.0.0-20230301143203-a9d515a09cc2 // indirect

go.sum

@@ -1,5 +1,7 @@
 github.com/alexedwards/scs/v2 v2.8.0 h1:h31yUYoycPuL0zt14c0gd+oqxfRwIj6SOjHdKRZxhEw=
 github.com/alexedwards/scs/v2 v2.8.0/go.mod h1:ToaROZxyKukJKT/xLcVQAChi5k6+Pn1Gvmdl7h3RRj8=
+github.com/asaskevich/govalidator v0.0.0-20230301143203-a9d515a09cc2 h1:DklsrG3dyBCFEj5IhUbnKptjxatkF07cF2ak3yi77so=
+github.com/asaskevich/govalidator v0.0.0-20230301143203-a9d515a09cc2/go.mod h1:WaHUgvxTVq04UNunO+XhnAqY/wQc+bxr74GqbsZ/Jqw=
 github.com/go-chi/chi/v5 v5.0.14 h1:PyEwo2Vudraa0x/Wl6eDRRW2NXBvekgfxyydcM0WGE0=
 github.com/go-chi/chi/v5 v5.0.14/go.mod h1:DslCQbL2OYiznFReuXYUmQ2hGd1aDpCnlMNITLSKoi8=
 github.com/justinas/nosurf v1.1.1 h1:92Aw44hjSK4MxJeMSyDa7jwuI9GR2J/JCQiaKvXXSlk=

internal/forms/forms.go

@@ -5,6 +5,8 @@ import (
 	"net/http"
 	"net/url"
 	"strings"
+
+	"github.com/asaskevich/govalidator"
 )
 
 // Form creates a custom form struct, embeds a url.Values object
@@ -51,3 +53,11 @@ func (f *Form) MinLength(field string, length int, r *http.Request) bool {
     }
     return true
 }
+
+// IsEmail checks the email address
+func (f *Form) IsEmail(field string, r *http.Request) {
+    value := r.Form.Get(field)
+    if !govalidator.IsEmail(value) {
+        f.Errors.Add(field, "Invalid email address")
+    }
+}

internal/handlers/handlers.go

@@ -101,6 +101,7 @@ func (m *Repository) PostMakeReservation(w http.ResponseWriter, r *http.Request)
 
 	form.Required("first_name", "last_name", "email")
     form.MinLength("first_name", 2, r)
+    form.IsEmail("email", r)
 
 	if !form.Valid() {
 		data := make(map[string]interface{})