Add auth stmp mailer

README.md

@@ -30,6 +30,7 @@ It runs <a href="https://en.wikipedia.org/wiki/Directed_acyclic_graph">DAGs (Dir
 - Install by placing just a single binary file
 - Schedule executions of DAGs with Cron expressions
 - Define dependencies between related jobs and represent them as a single DAG (unit of execution)
+- Send email notifications upon DAG execution error/success with simple configuration
 
 ## Contents
 
@@ -66,6 +67,7 @@ It runs <a href="https://en.wikipedia.org/wiki/Directed_acyclic_graph">DAGs (Dir
   - [HTTP Executor](#http-executor)
 - [Admin Configuration](#admin-configuration)
 - [Environment Variable](#environment-variable)
+- [Sending email notifications](#sending-email-notifications)
 - [Base Configuration for all DAGs](#base-configuration-for-all-dags)
 - [Scheduler](#scheduler)
   - [Execution Schedule](#execution-schedule)
@@ -488,24 +490,73 @@ command: <Absolute path to the dagu binary>                  # default: dagu
 
 You can configure the dagu's internal work directory by defining `DAGU_HOME` environment variables. Default path is `~/.dagu/`.
 
+## Sending email notifications
+
+Email notifications can be sent when a DAG finished with an error or successfully. To do so, you can set the `stmp` field and related fields in the DAG specs. You can use any email delivery services (e.g., Sendgrid, Mailgun, etc).
+
+```yaml
+# Eamil notification settings
+mailOn:
+  failure: true
+  success: true
+
+# SMTP server settings
+smtp:
+  host: "smtp.foo.bar"
+  port: "587"
+  username: "<username>"
+  password: "<password>"
+
+# Error mail configuration
+errorMail:
+  from: "[email protected]"
+  to: "[email protected]"
+  prefix: "[Error]"
+
+# Info mail configuration
+infoMail:
+  from: "[email protected]"
+  to: "[email protected]"
+  prefix: "[Info]"
+```
+
+If you want to use the same settings for all DAGs, set them to the [base configuration](#base-configuration-for-all-dags).
+
+
 ## Base Configuration for all DAGs
 
 Creating a base configuration (default path: `~/.dagu/config.yaml`) is a convenient way to organize shared settings among all DAGs. The path to the base configuration file can be configured. See [Admin Configuration](#admin-configuration) for more details.
 
 ```yaml
-logDir: <path-to-write-log>         # log directory to write standard output
-histRetentionDays: 3                # history retention days
-smtp:                               # [optional] mail server configuration to send notifications
-  host: <smtp server host>
-  port: <stmp server port>
-errorMail:                          # [optional] mail configuration for error-level
-  from: <from address>
-  to: <to address>
-  prefix: <prefix of mail subject>
+# directory path to save logs from standard output
+logDir: /path/to/stdout-logs/
+
+# history retention days (default: 30)
+histRetentionDays: 3
+
+# Eamil notification settings
+mailOn:
+  failure: true
+  success: true
+
+# SMTP server settings
+smtp:
+  host: "smtp.foo.bar"
+  port: "587"
+  username: "<username>"
+  password: "<password>"
+
+# Error mail configuration
+errorMail:
+  from: "[email protected]"
+  to: "[email protected]"
+  prefix: "[Error]"
+
+# Info mail configuration
 infoMail:
-  from: <from address>              # [optional] mail configuration for info-level
-  to: <to address>
-  prefix: <prefix of mail subject>
+  from: "[email protected]"
+  to: "[email protected]"
+  prefix: "[Info]"
 ```
 
 ## Scheduler

agent.go

@@ -167,8 +167,10 @@ func (a *Agent) init() {
 		Config: &reporter.Config{
 			Mailer: &mailer.Mailer{
 				Config: &mailer.Config{
-					Host: a.DAG.Smtp.Host,
-					Port: a.DAG.Smtp.Port,
+					Host:     a.DAG.Smtp.Host,
+					Port:     a.DAG.Smtp.Port,
+					Username: a.DAG.Smtp.Username,
+					Password: a.DAG.Smtp.Password,
 				},
 			},
 		}}

examples/email_example.yaml

@@ -0,0 +1,21 @@
+steps:
+  - name: S1
+    command: echo "hello"
+
+mailOn:
+  failure: true
+  success: true
+
+smtp:
+  host: "smtp.foo.bar"
+  port: "587"
+  username: "<username>"
+  password: "<password>"
+errorMail:
+  from: "[email protected]"
+  to: "[email protected]"
+  prefix: "[Error]"
+infoMail:
+  from: "[email protected]"
+  to: "[email protected]"
+  prefix: "[Info]"

examples/minimal.yaml

@@ -4,6 +4,6 @@ steps:
   - name: step 1
     command: echo $1
   - name: step 2
-    command: sleep 50
+    command: sleep 1
     depends:
       - step 1

internal/dag/dag.go

@@ -568,6 +568,8 @@ func buildSmtpConfigFromDefinition(def *configDefinition, d *DAG) (err error) {
 	smtp := &SmtpConfig{}
 	smtp.Host = def.Smtp.Host
 	smtp.Port = def.Smtp.Port
+	smtp.Username = def.Smtp.Username
+	smtp.Password = def.Smtp.Password
 	d.Smtp = smtp
 	return nil
 }

internal/dag/definition.go

@@ -71,8 +71,10 @@ type retryPolicyDef struct {
 }
 
 type smtpConfigDef struct {
-	Host string
-	Port string
+	Host     string
+	Port     string
+	Username string
+	Password string
 }
 
 type mailConfigDef struct {

internal/dag/mail.go

@@ -1,8 +1,10 @@
 package dag
 
 type SmtpConfig struct {
-	Host string
-	Port string
+	Host     string
+	Port     string
+	Username string
+	Password string
 }
 
 type MailConfig struct {

internal/mailer/mailer.go

@@ -14,29 +14,38 @@ type Mailer struct {
 
 // Config is a config for SMTP mailer.
 type Config struct {
-	// Host is a hostname of a mail server.
-	Host string
-	// Port is a port of a mail server.
-	Port string
+	Host     string
+	Port     string
+	Username string
+	Password string
 }
 
+var (
+	replacer = strings.NewReplacer("\r\n", "", "\r", "", "\n", "", "%0a", "", "%0d", "")
+)
+
 // SendMail sends an email.
 func (m *Mailer) SendMail(from string, to []string, subject, body string) error {
 	log.Printf("Sending an email to %s, subject is \"%s\"", strings.Join(to, ","), subject)
-	r := strings.NewReplacer("\r\n", "", "\r", "", "\n", "", "%0a", "", "%0d", "")
+	if m.Username == "" && m.Password == "" {
+		return m.sendWithNoAuth(from, to, subject, body)
+	}
+	return m.sendWithAuth(from, to, subject, body)
+}
 
+func (m *Mailer) sendWithNoAuth(from string, to []string, subject, body string) error {
 	c, err := smtp.Dial(m.Host + ":" + m.Port)
 	if err != nil {
 		return err
 	}
 	defer func() {
 		_ = c.Close()
 	}()
-	if err = c.Mail(r.Replace(from)); err != nil {
+	if err = c.Mail(replacer.Replace(from)); err != nil {
 		return err
 	}
 	for i := range to {
-		to[i] = r.Replace(to[i])
+		to[i] = replacer.Replace(to[i])
 		if err = c.Rcpt(to[i]); err != nil {
 			return err
 		}
@@ -60,3 +69,13 @@ func (m *Mailer) SendMail(from string, to []string, subject, body string) error
 	}
 	return c.Quit()
 }
+
+func (m *Mailer) sendWithAuth(from string, to []string, subject, body string) error {
+	auth := smtp.PlainAuth("", m.Username, m.Password, m.Host)
+	return smtp.SendMail(m.Host+":"+m.Port, auth, from, to, []byte("To: "+strings.Join(to, ",")+"\r\n"+
+		"From: "+from+"\r\n"+
+		"Subject: "+subject+"\r\n"+
+		"Content-Type: text/html; charset=\"UTF-8\"\r\n"+
+		"Content-Transfer-Encoding: base64\r\n"+
+		"\r\n"+base64.StdEncoding.EncodeToString([]byte(body))))
+}