notifications: pick SMTP auth method automatically by default

This introduces the new value `auto` for NOTIFICATIONS_SMTP_AUTHENTICATION.
Which will make the notifications service automatically pick an authentication
mechanism that the server supports. This is also the new default behavior.

This also removes most of the other default settings for the SMTP
configuration. The default values were of no real use for this service.

Closes: #7356

.drone.star

@@ -138,6 +138,7 @@ config = {
                 "NOTIFICATIONS_SMTP_HOST": "email",
                 "NOTIFICATIONS_SMTP_PORT": "2500",
                 "NOTIFICATIONS_SMTP_INSECURE": "true",
+                "NOTIFICATIONS_SMTP_SENDER": "ownCloud <noreply@example.com>",
             },
         },
         "apiAntivirus": {

changelog/unreleased/enhancement-notifications-auto-auth-settings.md

@@ -0,0 +1,7 @@
+Enhancement: New value `auto` for NOTIFICATIONS_SMTP_AUTHENTICATION
+
+This cause the notifications service to automatically pick a suitable authentication
+method to use with the configured SMTP server. This is also the new default behavior.
+The previous default was to not use authentication at all.
+
+https://github.com/owncloud/ocis/issues/7356

services/notifications/pkg/channels/channels.go

@@ -69,6 +69,8 @@ func (m Mail) getMailClient() (*mail.SMTPClient, error) {
 		server.Authentication = mail.AuthCRAMMD5
 	case "none":
 		server.Authentication = mail.AuthNone
+	case "auto", "":
+		server.Authentication = mail.AuthAuto
 	default:
 		return nil, errors.New("unknown mail authentication method")
 	}

services/notifications/pkg/config/config.go

@@ -39,11 +39,11 @@ type Notifications struct {
 type SMTP struct {
 	Host           string `yaml:"smtp_host" env:"NOTIFICATIONS_SMTP_HOST" desc:"SMTP host to connect to."`
 	Port           int    `yaml:"smtp_port" env:"NOTIFICATIONS_SMTP_PORT" desc:"Port of the SMTP host to connect to."`
-	Sender         string `yaml:"smtp_sender" env:"NOTIFICATIONS_SMTP_SENDER" desc:"Sender address of emails that will be sent."`
+	Sender         string `yaml:"smtp_sender" env:"NOTIFICATIONS_SMTP_SENDER" desc:"Sender address of emails that will be sent (e.g. 'ownCloud <noreply@example.com>'."`
 	Username       string `yaml:"smtp_username" env:"NOTIFICATIONS_SMTP_USERNAME" desc:"Username for the SMTP host to connect to."`
 	Password       string `yaml:"smtp_password" env:"NOTIFICATIONS_SMTP_PASSWORD" desc:"Password for the SMTP host to connect to."`
 	Insecure       bool   `yaml:"insecure" env:"NOTIFICATIONS_SMTP_INSECURE" desc:"Allow insecure connections to the SMTP server."`
-	Authentication string `yaml:"smtp_authentication" env:"NOTIFICATIONS_SMTP_AUTHENTICATION" desc:"Authentication method for the SMTP communication. Possible values are 'login', 'plain', 'crammd5', 'none'"`
+	Authentication string `yaml:"smtp_authentication" env:"NOTIFICATIONS_SMTP_AUTHENTICATION" desc:"Authentication method for the SMTP communication. Possible values are 'login', 'plain', 'crammd5', 'none' or 'auto'. If set to 'auto' or unset, the authentication method is automatically negotiated with the server."`
 	Encryption     string `yaml:"smtp_encryption" env:"NOTIFICATIONS_SMTP_ENCRYPTION" desc:"Encryption method for the SMTP communication. Possible values  are 'starttls', 'ssl', 'ssltls', 'tls'  and 'none'." deprecationVersion:"5.0.0" removalVersion:"6.0.0" deprecationInfo:"The NOTIFICATIONS_SMTP_ENCRYPTION values 'ssl' and 'tls' are deprecated and will be removed in the future." deprecationReplacement:"Use 'starttls' instead of 'tls' and 'ssltls' instead of 'ssl'."`
 }
 

services/notifications/pkg/config/defaults/defaultconfig.go

@@ -31,11 +31,7 @@ func DefaultConfig() *config.Config {
 		WebUIURL: "https://localhost:9200",
 		Notifications: config.Notifications{
 			SMTP: config.SMTP{
-				Host:           "",
-				Port:           1025,
-				Sender:         "ownCloud <noreply@example.com>",
-				Authentication: "none",
-				Encryption:     "none",
+				Encryption: "none",
 			},
 			Events: config.Events{
 				Endpoint:  "127.0.0.1:9233",