Added a check for a website field's length.

guestbook.go

@@ -2,6 +2,7 @@ package justguestbook
 
 import (
 	"errors"
+	"fmt"
 	"time"
 )
 
@@ -9,6 +10,9 @@ const (
 	// DateFormat is a format of the date and time used in a guestbook.
 	DateFormat = "2006-01-02 15:04:05"
 
+	// entryWebsiteMaxLength is a maximum length for a Website field of an Entry.
+	entryWebsiteMaxLength = 255
+)
 
 // Reply holds a reply for a guestbook's entry.
 type Reply struct {
@@ -68,6 +72,11 @@ func NewEntry(name, message, website string, hideWebsite bool) (*Entry, error) {
 		return nil, errors.New("name and message field are required")
 	}
 
+	if len(website) > entryWebsiteMaxLength {
+		return nil, errors.New(fmt.Sprint("website field's max length is",
+			entryWebsiteMaxLength, "but", len(website), "was given"))
+	}
+
 	return &Entry{
 		Created:     time.Now().UTC(),
 		Name:        name,