Refactor notifications to use a cleaner interface

notifications.go

@@ -8,12 +8,27 @@ import (
 	"text/template"
 )
 
+type headerData struct {
+	name  string
+	value []string
+}
+
+type headerList []headerData
+
+type recipientData struct {
+	field, address, name string
+}
+
+type notificationContent struct {
+	template   string
+	data       interface{}
+	subject    string
+	headers    headerList
+	recipients []recipientData
+}
+
 type NotificationMail interface {
-	GetData() interface{}
+	GetNotificationContent() *notificationContent
-	GetTemplate() string
-	GetSubject() string
-	GetHeaders() map[string]string
-	GetRecipient() (string, string)
 }
 
 var NotifyMailChannel = make(chan NotificationMail, 1)
@@ -23,19 +38,21 @@ func MailNotifier(quitMailNotifier chan int) {
 	for {
 		select {
 		case notification := <-NotifyMailChannel:
-			mailText, err := buildMail(notification.GetTemplate(), notification.GetData())
+			content := notification.GetNotificationContent()
+			mailText, err := buildMail(content.template, content.data)
 			if err != nil {
 				logger.Println("ERROR building mail:", err)
 				continue
 			}
 
 			m := gomail.NewMessage()
-			m.SetHeader("From", config.NotificationSenderAddress)
+			m.SetAddressHeader("From", config.NotificationSenderAddress, "CAcert board voting system")
-			address, name := notification.GetRecipient()
+			for _, recipient := range content.recipients {
-			m.SetAddressHeader("To", address, name)
+				m.SetAddressHeader(recipient.field, recipient.address, recipient.name)
-			m.SetHeader("Subject", notification.GetSubject())
+			}
-			for header, value := range notification.GetHeaders() {
+			m.SetHeader("Subject", content.subject)
-				m.SetHeader(header, value)
+			for _, header := range content.headers {
+				m.SetHeader(header.name, header.value...)
 			}
 			m.SetBody("text/plain", mailText.String())
 
@@ -65,45 +82,52 @@ func buildMail(templateName string, context interface{}) (mailText *bytes.Buffer
 
 type notificationBase struct{}
 
-func (n *notificationBase) GetRecipient() (address string, name string) {
+func (n *notificationBase) getRecipient() recipientData {
-	address, name = config.BoardMailAddress, "CAcert board mailing list"
+	return recipientData{field: "To", address: config.BoardMailAddress, name: "CAcert board mailing list"}
-	return
 }
 
 type decisionReplyBase struct {
 	decision Decision
 }
 
-func (n *decisionReplyBase) GetHeaders() map[string]string {
+func (n *decisionReplyBase) getHeaders() headerList {
-	return map[string]string{
+	headers := make(headerList, 0)
-		"References":  fmt.Sprintf("<%s>", n.decision.Tag),
+	headers = append(headers, headerData{
-		"In-Reply-To": fmt.Sprintf("<%s>", n.decision.Tag),
+		name: "References", value: []string{fmt.Sprintf("<%s>", n.decision.Tag)},
-	}
+	})
+	headers = append(headers, headerData{
+		name: "In-Reply-To", value: []string{fmt.Sprintf("<%s>", n.decision.Tag)},
+	})
+	return headers
+}
+
+func (n *decisionReplyBase) getSubject() string {
+	return fmt.Sprintf("Re: %s - %s", n.decision.Tag, n.decision.Title)
 }
 
-type NotificationClosedDecision struct {
+type notificationClosedDecision struct {
 	notificationBase
 	decisionReplyBase
 	voteSums VoteSums
 }
 
-func NewNotificationClosedDecision(decision *Decision, voteSums *VoteSums) *NotificationClosedDecision {
+func NewNotificationClosedDecision(decision *Decision, voteSums *VoteSums) NotificationMail {
-	notification := &NotificationClosedDecision{voteSums: *voteSums}
+	notification := &notificationClosedDecision{voteSums: *voteSums}
 	notification.decision = *decision
 	return notification
 }
 
-func (n *NotificationClosedDecision) GetData() interface{} {
+func (n *notificationClosedDecision) GetNotificationContent() *notificationContent {
-	return struct {
+	return &notificationContent{
-		*Decision
+		template: "closed_motion_mail.txt",
-		*VoteSums
+		data: struct {
-	}{&n.decision, &n.voteSums}
+			*Decision
-}
+			*VoteSums
-
+		}{&n.decision, &n.voteSums},
-func (n *NotificationClosedDecision) GetTemplate() string { return "closed_motion_mail.txt" }
+		subject:    fmt.Sprintf("Re: %s - %s - finalised", n.decision.Tag, n.decision.Title),
-
+		headers:    n.decisionReplyBase.getHeaders(),
-func (n *NotificationClosedDecision) GetSubject() string {
+		recipients: []recipientData{n.notificationBase.getRecipient()},
-	return fmt.Sprintf("Re: %s - %s - finalised", n.decision.Tag, n.decision.Title)
+	}
 }
 
 type NotificationCreateMotion struct {
@@ -112,79 +136,75 @@ type NotificationCreateMotion struct {
 	voter    Voter
 }
 
-func (n *NotificationCreateMotion) GetData() interface{} {
+func (n *NotificationCreateMotion) GetNotificationContent() *notificationContent {
 	voteURL := fmt.Sprintf("%s/vote/%s", config.BaseURL, n.decision.Tag)
 	unvotedURL := fmt.Sprintf("%s/motions/?unvoted=1", config.BaseURL)
-	return struct {
+	return &notificationContent{
-		*Decision
+		template: "create_motion_mail.txt",
-		Name       string
+		data: struct {
-		VoteURL    string
+			*Decision
-		UnvotedURL string
+			Name       string
-	}{&n.decision, n.voter.Name, voteURL, unvotedURL}
+			VoteURL    string
-}
+			UnvotedURL string
-
+		}{&n.decision, n.voter.Name, voteURL, unvotedURL},
-func (n *NotificationCreateMotion) GetTemplate() string { return "create_motion_mail.txt" }
+		subject:    fmt.Sprintf("%s - %s", n.decision.Tag, n.decision.Title),
-
+		headers:    headerList{headerData{"Message-ID", []string{fmt.Sprintf("<%s>", n.decision.Tag)}}},
-func (n *NotificationCreateMotion) GetSubject() string {
+		recipients: []recipientData{n.notificationBase.getRecipient()},
-	return fmt.Sprintf("%s - %s", n.decision.Tag, n.decision.Title)
+	}
-}
-
-func (n *NotificationCreateMotion) GetHeaders() map[string]string {
-	return map[string]string{"Message-ID": fmt.Sprintf("<%s>", n.decision.Tag)}
 }
 
-type NotificationUpdateMotion struct {
+type notificationUpdateMotion struct {
 	notificationBase
 	decisionReplyBase
 	voter Voter
 }
 
-func NewNotificationUpdateMotion(decision Decision, voter Voter) *NotificationUpdateMotion {
+func NewNotificationUpdateMotion(decision Decision, voter Voter) NotificationMail {
-	notification := NotificationUpdateMotion{voter: voter}
+	notification := notificationUpdateMotion{voter: voter}
 	notification.decision = decision
 	return &notification
 }
 
-func (n *NotificationUpdateMotion) GetData() interface{} {
+func (n *notificationUpdateMotion) GetNotificationContent() *notificationContent {
 	voteURL := fmt.Sprintf("%s/vote/%s", config.BaseURL, n.decision.Tag)
 	unvotedURL := fmt.Sprintf("%s/motions/?unvoted=1", config.BaseURL)
-	return struct {
+	return &notificationContent{
-		*Decision
+		template: "update_motion_mail.txt",
-		Name       string
+		data: struct {
-		VoteURL    string
+			*Decision
-		UnvotedURL string
+			Name       string
-	}{&n.decision, n.voter.Name, voteURL, unvotedURL}
+			VoteURL    string
-}
+			UnvotedURL string
-
+		}{&n.decision, n.voter.Name, voteURL, unvotedURL},
-func (n *NotificationUpdateMotion) GetTemplate() string { return "update_motion_mail.txt" }
+		subject:    n.decisionReplyBase.getSubject(),
-
+		headers:    n.decisionReplyBase.getHeaders(),
-func (n *NotificationUpdateMotion) GetSubject() string {
+		recipients: []recipientData{n.notificationBase.getRecipient()},
-	return fmt.Sprintf("Re: %s - %s", n.decision.Tag, n.decision.Title)
+	}
 }
 
-type NotificationWithDrawMotion struct {
+type notificationWithDrawMotion struct {
 	notificationBase
 	decisionReplyBase
 	voter Voter
 }
 
-func NewNotificationWithDrawMotion(decision *Decision, voter *Voter) *NotificationWithDrawMotion {
+func NewNotificationWithDrawMotion(decision *Decision, voter *Voter) NotificationMail {
-	notification := &NotificationWithDrawMotion{voter: *voter}
+	notification := &notificationWithDrawMotion{voter: *voter}
 	notification.decision = *decision
 	return notification
 }
 
-func (n *NotificationWithDrawMotion) GetData() interface{} {
+func (n *notificationWithDrawMotion) GetNotificationContent() *notificationContent {
-	return struct {
+	return &notificationContent{
-		*Decision
+		template: "withdraw_motion_mail.txt",
-		Name string
+		data: struct {
-	}{&n.decision, n.voter.Name}
+			*Decision
-}
+			Name string
-
+		}{&n.decision, n.voter.Name},
-func (n *NotificationWithDrawMotion) GetTemplate() string { return "withdraw_motion_mail.txt" }
+		subject:    fmt.Sprintf("Re: %s - %s - withdrawn", n.decision.Tag, n.decision.Title),
-
+		headers:    n.decisionReplyBase.getHeaders(),
-func (n *NotificationWithDrawMotion) GetSubject() string {
+		recipients: []recipientData{n.notificationBase.getRecipient()},
-	return fmt.Sprintf("Re: %s - %s - withdrawn", n.decision.Tag, n.decision.Title)
+	}
 }
 
 type RemindVoterNotification struct {
@@ -192,35 +212,26 @@ type RemindVoterNotification struct {
 	decisions []Decision
 }
 
-func (n *RemindVoterNotification) GetData() interface{} {
+func (n *RemindVoterNotification) GetNotificationContent() *notificationContent {
-	return struct {
+	return &notificationContent{
-		Decisions []Decision
+		template: "remind_voter_mail.txt",
-		Name      string
+		data: struct {
-		BaseURL   string
+			Decisions []Decision
-	}{n.decisions, n.voter.Name, config.BaseURL}
+			Name      string
-}
+			BaseURL   string
-
+		}{n.decisions, n.voter.Name, config.BaseURL},
-func (n *RemindVoterNotification) GetTemplate() string { return "remind_voter_mail.txt" }
+		subject:    "Outstanding CAcert board votes",
-
+		recipients: []recipientData{{"To", n.voter.Reminder, n.voter.Name}},
-func (n *RemindVoterNotification) GetSubject() string { return "Outstanding CAcert board votes" }
+	}
-
-func (n *RemindVoterNotification) GetHeaders() map[string]string {
-	return map[string]string{}
-}
-
-func (n *RemindVoterNotification) GetRecipient() (address string, name string) {
-	address, name = n.voter.Reminder, n.voter.Name
-	return
 }
 
 type voteNotificationBase struct{}
 
-func (n *voteNotificationBase) GetRecipient() (address string, name string) {
+func (n *voteNotificationBase) getRecipient() recipientData {
-	address, name = config.VoteNoticeAddress, "CAcert board votes mailing list"
+	return recipientData{"To", config.VoteNoticeAddress, "CAcert board votes mailing list"}
-	return
 }
 
-type NotificationProxyVote struct {
+type notificationProxyVote struct {
 	voteNotificationBase
 	decisionReplyBase
 	proxy         Voter
@@ -229,51 +240,51 @@ type NotificationProxyVote struct {
 	justification string
 }
 
-func NewNotificationProxyVote(decision *Decision, proxy *Voter, voter *Voter, vote *Vote, justification string) *NotificationProxyVote {
+func NewNotificationProxyVote(decision *Decision, proxy *Voter, voter *Voter, vote *Vote, justification string) NotificationMail {
-	notification := &NotificationProxyVote{proxy: *proxy, voter: *voter, vote: *vote, justification: justification}
+	notification := &notificationProxyVote{proxy: *proxy, voter: *voter, vote: *vote, justification: justification}
 	notification.decision = *decision
 	return notification
 }
 
-func (n *NotificationProxyVote) GetData() interface{} {
+func (n *notificationProxyVote) GetNotificationContent() *notificationContent {
-	return struct {
+	return &notificationContent{
-		Proxy         string
+		template: "proxy_vote_mail.txt",
-		Vote          VoteChoice
+		data: struct {
-		Voter         string
+			Proxy         string
-		Decision      *Decision
+			Vote          VoteChoice
-		Justification string
+			Voter         string
-	}{n.proxy.Name, n.vote.Vote, n.voter.Name, &n.decision, n.justification}
+			Decision      *Decision
-}
+			Justification string
-
+		}{n.proxy.Name, n.vote.Vote, n.voter.Name, &n.decision, n.justification},
-func (n *NotificationProxyVote) GetTemplate() string { return "proxy_vote_mail.txt" }
+		subject:    n.decisionReplyBase.getSubject(),
-
+		headers:    n.decisionReplyBase.getHeaders(),
-func (n *NotificationProxyVote) GetSubject() string {
+		recipients: []recipientData{n.voteNotificationBase.getRecipient()},
-	return fmt.Sprintf("Re: %s - %s", n.decision.Tag, n.decision.Title)
+	}
 }
 
-type NotificationDirectVote struct {
+type notificationDirectVote struct {
 	voteNotificationBase
 	decisionReplyBase
 	voter Voter
 	vote  Vote
 }
 
-func NewNotificationDirectVote(decision *Decision, voter *Voter, vote *Vote) *NotificationDirectVote {
+func NewNotificationDirectVote(decision *Decision, voter *Voter, vote *Vote) NotificationMail {
-	notification := &NotificationDirectVote{voter: *voter, vote: *vote}
+	notification := &notificationDirectVote{voter: *voter, vote: *vote}
 	notification.decision = *decision
 	return notification
 }
 
-func (n *NotificationDirectVote) GetData() interface{} {
+func (n *notificationDirectVote) GetNotificationContent() *notificationContent {
-	return struct {
+	return &notificationContent{
-		Vote     VoteChoice
+		template: "direct_vote_mail.txt",
-		Voter    string
+		data: struct {
-		Decision *Decision
+			Vote     VoteChoice
-	}{n.vote.Vote, n.voter.Name, &n.decision}
+			Voter    string
-}
+			Decision *Decision
-
+		}{n.vote.Vote, n.voter.Name, &n.decision},
-func (n *NotificationDirectVote) GetTemplate() string { return "direct_vote_mail.txt" }
+		subject:    n.decisionReplyBase.getSubject(),
-
+		headers:    n.decisionReplyBase.getHeaders(),
-func (n *NotificationDirectVote) GetSubject() string {
+		recipients: []recipientData{n.voteNotificationBase.getRecipient()},
-	return fmt.Sprintf("Re: %s - %s", n.decision.Tag, n.decision.Title)
+	}
 }