allow sending mails w/o attachments :-)

src/model/mail.rs

@@ -52,15 +52,17 @@ impl Mail {
             let content = fs::read(temp_file.path().unwrap()).unwrap();
             let media_type = format!("{}", temp_file.content_type().unwrap().media_type());
             let content_type = ContentType::parse(&media_type).unwrap();
+            if let Some(name) = temp_file.name() {
                 let attachment = Attachment::new(format!(
                     "{}.{}",
-                temp_file.name().unwrap(),
+                    name,
                     temp_file.content_type().unwrap().extension().unwrap()
                 ))
                 .body(content, content_type);
 
                 multipart = multipart.singlepart(attachment);
             }
+        }
 
         let email = email.subject(data.subject).multipart(multipart).unwrap();