Added mail notification support

api/form_handlers.go

@@ -59,11 +59,20 @@ func FormCreate(c *fiber.Ctx, cfg *cfg.Config, db *Db) error {
 		ex, err := common.Untaint(formdata.Expire, cfg.RegDuration) // duration or asap allowed
 		if err != nil {
 			return JsonStatus(c, fiber.StatusForbidden,
-				"Invalid data: "+err.Error())
+				"Invalid expire data: "+err.Error())
 		}
 		entry.Expire = ex
 	}
 
+	if len(formdata.Notify) != 0 {
+		nt, err := common.Untaint(formdata.Notify, cfg.RegEmail)
+		if err != nil {
+			return JsonStatus(c, fiber.StatusForbidden,
+				"Invalid email address: "+err.Error())
+		}
+		entry.Notify = nt
+	}
+
 	// get url [and zip if there are multiple files]
 	returnUrl := strings.Join([]string{cfg.Url, "form", id}, "/")
 	entry.Url = returnUrl

api/mail.go

@@ -0,0 +1,54 @@
+/*
+Copyright © 2023 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package api
+
+import (
+	"fmt"
+	"github.com/tlinden/cenophane/cfg"
+	"net/smtp"
+)
+
+var mailtpl string = `To: %s\r
+From: %s\r
+Subject: %s\r
+\r
+%s\r
+`
+
+/*
+   Send  an  email  via  an   external  mail  gateway.  SMTP  Auth  is
+   required. Errors may occur with  a time delay, like server timeouts
+   etc. So only call it detached via go routine.
+*/
+func Sendmail(c *cfg.Config, recipient string, body string, subject string) error {
+	// Message.
+	message := []byte(fmt.Sprintf(mailtpl, recipient, c.Mail.From, subject, body))
+
+	// Authentication.
+	auth := smtp.PlainAuth("", c.Mail.From, c.Mail.Password, c.Mail.Server)
+
+	// Sending email.
+	Log("Trying to send mail to %s via %s:%s with subject %s",
+		recipient, c.Mail.Server, c.Mail.Port, subject)
+	err := smtp.SendMail(c.Mail.Server+":"+c.Mail.Port, auth, c.Mail.From, []string{recipient}, []byte(message))
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

api/upload_handlers.go

@@ -24,6 +24,7 @@ import (
 	"github.com/tlinden/cenophane/cfg"
 	"github.com/tlinden/cenophane/common"
 
+	"fmt"
 	"os"
 	"path/filepath"
 	"strings"
@@ -122,7 +123,7 @@ func UploadPost(c *fiber.Ctx, cfg *cfg.Config, db *Db) error {
 
 	// ok, check  if we need to remove  a form, if so we do  it in the
 	// background.  delete error  doesn't lead  to upload  failure, we
-	// only log it.
+	// only log it. same applies to mail notification.
 	formid, _ := SessionGetFormId(c)
 	if formid != "" {
 		go func() {
@@ -132,6 +133,16 @@ func UploadPost(c *fiber.Ctx, cfg *cfg.Config, db *Db) error {
 					if r.Forms[0].Expire == "asap" {
 						db.Delete(apicontext, formid)
 					}
+
+					// email notification to form creator
+					if r.Forms[0].Notify != "" {
+						body := fmt.Sprintf("Upload is available under: %s", returnUrl)
+						subject := fmt.Sprintf("Upload form %s has been used", formid)
+						err := Sendmail(cfg, r.Forms[0].Notify, body, subject)
+						if err != nil {
+							Log("Failed to send mail: %s", err.Error())
+						}
+					}
 				}
 			}
 		}()