refactor(lib): comment and clean up code

notify.go

@@ -4,31 +4,32 @@ import (
 	"github.com/pkg/errors"
 )
 
-type Notifier struct {
-	Disabled bool
-	services []Service
+const defaultDisabled = false // Notifier is enabled by default
+
+// Notify is the central struct for managing notification services and sending messages to them.
+type Notify struct {
+	Disabled  bool
+	notifiers []Notifier
 }
 
-const defaultDisabled = false
-
+// ErrSendNotification signals that the notifier failed to send a notification.
 var ErrSendNotification = errors.New("Send notification")
 
-// Service implements a Listen and a Send method. The Listen method makes the notification Service listens
-// for external commands and will answer to these commands if supported. For example, our telegram Notifier listens for
-// commands like /info and will answer with basic information about the server. The Send command simply sends a
-// message string to the internal destination Service. E.g for telegram it sends the message to the specified group
-// chat.
-type Service interface {
+// Notifier defines the behavior for notification services. The Send command simply sends a message string to the
+// internal destination Notifier. E.g for telegram it sends the message to the specified group chat.
+type Notifier interface {
 	Send(string, string) error
 }
 
-func New() *Notifier {
-	notifier := &Notifier{
+// New returns a new instance of Notify. Defaulting to being not disabled and using the pseudo notification
+// service under the hood.
+func New() *Notify {
+	notifier := &Notify{
 		Disabled: defaultDisabled,
 	}
 
-	// Use the pseudo Service to prevent from nil reference bugs when using the Notifier Service. In case no services
-	// are provided or the creation of all other services failed, the pseudo Service will be used under the hood
+	// Use the pseudo Notifier to prevent from nil reference bugs when using the Notify Notifier. In case no notifiers
+	// are provided or the creation of all other notifiers failed, the pseudo Notifier will be used under the hood
 	// doing nothing but preventing nil-reference errors.
 	notifier.usePseudo()
 

send.go

@@ -5,14 +5,15 @@ import (
 	"golang.org/x/sync/errgroup"
 )
 
-func (n Notifier) Send(subject, message string) error {
+// Send calls the underlying notification services to send the given message to their respective endpoints.
+func (n Notify) Send(subject, message string) error {
 	if n.Disabled {
 		return nil
 	}
 
 	var eg errgroup.Group
 
-	for _, service := range n.services {
+	for _, service := range n.notifiers {
 		if service != nil {
 			s := service
 			eg.Go(func() error {

service/discord/discord.go

@@ -5,11 +5,13 @@ import (
 	"github.com/pkg/errors"
 )
 
+// Discord struct holds necessary data to communicate with the Discord API.
 type Discord struct {
 	client     *discordgo.Session
 	channelIDs []string
 }
 
+// New takes a Discord API token and returns a new instance of a Discord notification service.
 func New(apiToken string) (*Discord, error) {
 	client, err := discordgo.New("Bot " + apiToken)
 	if err != nil {
@@ -24,10 +26,13 @@ func New(apiToken string) (*Discord, error) {
 	return d, nil
 }
 
+// AddReceivers takes Telegram channel IDs and adds them to the internal channel ID list. The Send method will send
+// a given message to all those channels.
 func (d *Discord) AddReceivers(channelIDs ...string) {
 	d.channelIDs = append(d.channelIDs, channelIDs...)
 }
 
+// Send takes a message subject and a message body and sends them to all previously set chats.
 func (d Discord) Send(subject, message string) error {
 	fullMessage := subject + "\n" + message // Treating subject as message title
 

service/mail/mail.go

@@ -1,55 +1,57 @@
 package mail
 
 import (
+	"net/smtp"
+	"net/textproto"
+
+	"github.com/jordan-wright/email"
 	"github.com/pkg/errors"
-	gomail "gopkg.in/mail.v2"
-)
-
-const (
-	headerFrom      = "From"
-	headerTo        = "To"
-	headerSubject   = "Subject"
-	bodyContentType = "text/plain"
 )
 
+// Mail struct holds necessary data to send emails.
 type Mail struct {
-	client            *gomail.Dialer
+	senderAddress     string
+	smtpHostAddr      string
+	smtpAuth          smtp.Auth
 	receiverAddresses []string
 }
 
-func New(host, userName, password string, port int) (*Mail, error) {
-	client := gomail.NewDialer(host, port, userName, password)
-
-	m := &Mail{
-		client:            client,
+// New returns a new instance of a Mail notification service.
+func New(senderAddress, smtpHostAddress string) *Mail {
+	return &Mail{
+		senderAddress:     senderAddress,
+		smtpHostAddr:      smtpHostAddress,
 		receiverAddresses: []string{},
 	}
-
-	return m, nil
 }
 
+// AuthenticateSMTP authenticates you to send emails via smtp.
+// Example values: "", "test@gmail.com", "password123", "smtp.gmail.com"
+func (m *Mail) AuthenticateSMTP(identity, userName, password, host string) {
+	m.smtpAuth = smtp.PlainAuth(identity, userName, password, host)
+}
+
+// AddReceivers takes email addresses and adds them to the internal address list. The Send method will send
+// a given message to all those addresses.
 func (m *Mail) AddReceivers(addresses ...string) {
 	m.receiverAddresses = append(m.receiverAddresses, addresses...)
 }
 
+// Send takes a message subject and a message body and sends them to all previously set chats. Message body supports
+// html as markup language.
 func (m Mail) Send(subject, message string) error {
-	msg := gomail.NewMessage()
+	msg := &email.Email{
+		To:      m.receiverAddresses,
+		From:    m.senderAddress,
+		Subject: subject,
+		// Text:    []byte("Text Body is, of course, supported!"),
+		HTML:    []byte(message),
+		Headers: textproto.MIMEHeader{},
+	}
 
-	// Set E-Mail sender
-	msg.SetHeader(headerFrom, m.client.Host)
-
-	// Set E-Mail receivers
-	msg.SetHeader(headerTo, m.receiverAddresses...)
-
-	// Set E-Mail subject
-	msg.SetHeader(headerSubject, subject)
-
-	// Set E-Mail body
-	msg.SetBody(bodyContentType, message)
-
-	err := m.client.DialAndSend(msg)
+	err := msg.Send(m.smtpHostAddr, m.smtpAuth)
 	if err != nil {
-		err = errors.Wrap(err, "failed to dial and send mail")
+		err = errors.Wrap(err, "failed to send mail")
 	}
 
 	return err

service/pseudo/pseudo.go

@@ -2,10 +2,13 @@ package pseudo
 
 type Pseudo struct{}
 
+// New returns a new instance of a Pseudo notification service. This is used internally to initialize
+// notification services list and prevent nil-reference errors.
 func New() *Pseudo {
 	return &Pseudo{}
 }
 
+// Send basically does nothing. Just here to conform the notify.Notifier interface.
 func (Pseudo) Send(string, string) error {
 	return nil
 }

service/telegram/telegram.go

@@ -5,16 +5,16 @@ import (
 	"github.com/pkg/errors"
 )
 
-const (
-	defaultParseMode = tgbotapi.ModeHTML
-)
+const defaultParseMode = tgbotapi.ModeHTML
 
+// Telegram struct holds necessary data to communicate with the Telegram API.
 type Telegram struct {
 	client   *tgbotapi.BotAPI
 	listener *tgbotapi.BotAPI
 	chatIDs  []int64
 }
 
+// New returns a new instance of a Telegram notification service.
 func New(apiToken string) (*Telegram, error) {
 	client, err := tgbotapi.NewBotAPI(apiToken)
 	if err != nil {
@@ -29,10 +29,14 @@ func New(apiToken string) (*Telegram, error) {
 	return t, nil
 }
 
+// AddReceivers takes Telegram chat IDs and adds them to the internal chat ID list. The Send method will send
+// a given message to all those chats.
 func (t *Telegram) AddReceivers(chatIDs ...int64) {
 	t.chatIDs = append(t.chatIDs, chatIDs...)
 }
 
+// Send takes a message subject and a message body and sends them to all previously set chats. Message body supports
+// html as markup language.
 func (t Telegram) Send(subject, message string) error {
 	fullMessage := subject + "\n" + message // Treating subject as message title
 

use.go

@@ -4,55 +4,30 @@ import (
 	"github.com/nikoksr/notify/service/pseudo"
 )
 
-func (n *Notifier) useService(service Service) {
+// useService adds a given service to the notifiers services list. If the list still contains
+// a pseudo service we remove it before adding the 'real' service.
+func (n *Notify) useService(service Notifier) {
 	if service == nil {
 		return
 	}
 
 	// Remove pseudo service in case a 'real' service will be added
-	if len(n.services) > 0 {
-		_, isPseudo := n.services[0].(*pseudo.Pseudo)
+	if len(n.notifiers) > 0 {
+		_, isPseudo := n.notifiers[0].(*pseudo.Pseudo)
 		if isPseudo {
-			n.services = n.services[1:]
+			n.notifiers = n.notifiers[1:]
 		}
 	}
 
-	n.services = append(n.services, service)
+	n.notifiers = append(n.notifiers, service)
 }
 
-// usePseudo adds a pseudo Service to the Service list.
-func (n *Notifier) usePseudo() {
+// usePseudo adds a pseudo notification service to the notifiers services list.
+func (n *Notify) usePseudo() {
 	n.useService(pseudo.New())
 }
 
-func (n *Notifier) UseService(service Service) {
+// UseService adds a given service to the notifiers services list.
+func (n *Notify) UseService(service Notifier) {
 	n.useService(service)
 }
-
-/*
-func (n *Notifier) UseTelegram(apiToken string, chatID int64) error {
-	telegramService, err := telegram.New(apiToken)
-	if err != nil {
-		return err
-	}
-
-	telegramService.AddReceivers(chatID)
-
-	n.useService(telegramService)
-
-	return nil
-}
-
-func (n *Notifier) UseDiscordService(apiToken, channelID string) error {
-	discordService, err := discord.New(apiToken)
-	if err != nil {
-		return err
-	}
-
-	discordService.AddReceivers(channelID)
-
-	n.useService(discordService)
-
-	return nil
-}
-*/