Add base wrapper for handling smtp interactions

utils/smtp/smtp.go

@@ -0,0 +1,80 @@
+// Copyright © 2025 Prabhjot Singh Sethi, All Rights reserved
+// Author: Prabhjot Singh Sethi <prabhjot.sethi@gmail.com>
+
+// This is a wrapper over and above the standard net/smtp package
+// to enable generic client
+
+package smtp
+
+import (
+	"fmt"
+	"net/smtp"
+)
+
+// Base Configuration with which an smtp client will be created.
+type Config struct {
+	// smtp server host which is providing the mail services
+	// typically gmail smtp would be "smtp.gmail.com"
+	Host string
+
+	// port over which the smtp service is provided
+	Port string
+
+	// Sender email address / username for authentication
+	Sender string
+
+	// Password for authenticating the sender with smtp server
+	Password string
+}
+
+// Smtp Client handle, used for triggering sending messages
+type Client struct {
+	// smtp config object
+	config Config
+
+	// smtp endpoint
+	endpoint string
+}
+
+// Smtp message structure
+type Message struct {
+	// List of Receivers to whom this message is being sent
+	Receivers []string
+
+	// Subject of the message to be sent
+	Subject string
+
+	// Body of the email message to be sent
+	Body string
+
+	// if this is an HTML message
+	Html bool
+}
+
+// Create a new Client handle for the given config
+func New(config Config) *Client {
+	// create smtp endpoint with provided host and port
+	return &Client{
+		config:   config,
+		endpoint: fmt.Sprintf("%s:%s", config.Host, config.Port),
+	}
+}
+
+func (c *Client) Send(m *Message) error {
+	// Authentication.
+	auth := smtp.PlainAuth("", c.config.Sender, c.config.Password, c.config.Host)
+
+	mime := ""
+	if m.Html {
+		mime = "MIME-version: 1.0;\nContent-Type: text/html; charset=\"UTF-8\";\n\n"
+	}
+
+	message := fmt.Appendf(nil, "Subject: %s\n%s%s", m.Subject, mime, m.Body)
+	// Sending email.
+	err := smtp.SendMail(c.endpoint, auth, c.config.Sender, m.Receivers, message)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}