Generalize post reply notifications (#6)

## Summary - Notify the direct parent post author for replies throughout nested conversations - Skip root creation, self-replies, edits, disabled mail, and recipients without email - Link directly to each reply and use per-reply Resend idempotency Co-authored-by: codegirl-007 <s.raide@gmail.com>
2026-08-27 16:03:33 +00:00
parent 7412069ca6
commit f0591ccea3
8 changed files with 280 additions and 60 deletions
@@ -5,6 +5,7 @@ import (
 	_ "embed"
 	"fmt"
 	"html"
+	"net/url"
 	"os"
 	"strings"

@@ -14,24 +15,26 @@ import (
 //go:embed mark.png
 var markPNG []byte

-// QuestionAnswered is the payload for notifying a question author of a reply.
-type QuestionAnswered struct {
-	ToEmail       string
-	ToName        string
-	QuestionID    string
-	QuestionTitle string
-	AnswerBody    string
+// PostReply is the payload for notifying a post author of a direct reply.
+type PostReply struct {
+	ToEmail         string
+	ToName          string
+	RootID          string
+	RootTitle       string
+	ReplyID         string
+	ReplyBody       string
+	ReplyAuthorName string
 }

-// Notifier sends transactional email about answered questions.
+// Notifier sends transactional email about post replies.
 type Notifier interface {
-	NotifyQuestionAnswered(ctx context.Context, msg QuestionAnswered) error
+	NotifyPostReply(ctx context.Context, msg PostReply) error
 }

 // Nop is a no-op Notifier used when Resend is not configured.
 type Nop struct{}

-func (Nop) NotifyQuestionAnswered(context.Context, QuestionAnswered) error { return nil }
+func (Nop) NotifyPostReply(context.Context, PostReply) error { return nil }

 // Resend sends via the Resend HTTP API.
 type Resend struct {
@@ -62,7 +65,7 @@ func FromEnv() (Notifier, error) {
 	}, nil
 }

-func (r *Resend) NotifyQuestionAnswered(ctx context.Context, msg QuestionAnswered) error {
+func (r *Resend) NotifyPostReply(ctx context.Context, msg PostReply) error {
 	if r == nil || r.client == nil {
 		return nil
 	}
@@ -70,59 +73,72 @@ func (r *Resend) NotifyQuestionAnswered(ctx context.Context, msg QuestionAnswere
 	if to == "" {
 		return nil
 	}
-	text, htmlBody := questionAnsweredContent(r.baseURL, msg)
+	text, htmlBody := postReplyContent(r.baseURL, msg)
 	params := &resend.SendEmailRequest{
 		From:    r.from,
 		To:      []string{to},
-		Subject: "Your question was answered",
+		Subject: "New reply to your post",
 		Text:    text,
 		Html:    htmlBody,
 		Attachments: []*resend.Attachment{{
 			Content:     markPNG,
 			Filename:    "ask-a-plumber-first.png",
 			ContentType: "image/png",
-			ContentId:   "answer-notification-mark",
+			ContentId:   "reply-notification-mark",
 		}},
 	}
 	opts := &resend.SendEmailOptions{
-		IdempotencyKey: "answer-notify:" + msg.QuestionID,
+		IdempotencyKey: "post-reply:" + msg.ReplyID,
 	}
 	_, err := r.client.Emails.SendWithOptions(ctx, params, opts)
 	return err
 }

-func questionAnsweredContent(baseURL string, msg QuestionAnswered) (string, string) {
-	link := strings.TrimRight(baseURL, "/") + "/questions/" + msg.QuestionID
-	title := strings.TrimSpace(msg.QuestionTitle)
-	if title == "" {
-		title = "your question"
+func postReplyContent(baseURL string, msg PostReply) (string, string) {
+	link := strings.TrimRight(baseURL, "/") +
+		"/questions/" + url.PathEscape(msg.RootID) +
+		"#post-" + url.PathEscape(msg.ReplyID)
+	title := replyRootTitle(msg.RootTitle)
+	author := strings.TrimSpace(msg.ReplyAuthorName)
+	if author == "" {
+		author = "Someone"
 	}
 	text := fmt.Sprintf(
-		"Hi%s,\n\nYour question %q has an answer from a plumber:\n\n%s\n\nView it here:\n%s\n",
+		"Hi%s,\n\n%s replied in %q:\n\n%s\n\nView the reply:\n%s\n",
 		greetingName(msg.ToName),
+		author,
 		title,
-		msg.AnswerBody,
+		msg.ReplyBody,
 		link,
 	)
 	htmlBody := strings.NewReplacer(
-		"{{PREHEADER}}", html.EscapeString("A plumber answered "+title+"."),
+		"{{PREHEADER}}", html.EscapeString(author+" replied in "+title+"."),
 		"{{GREETING}}", html.EscapeString(greetingName(msg.ToName)),
 		"{{TITLE}}", html.EscapeString(title),
-		"{{ANSWER}}", html.EscapeString(msg.AnswerBody),
+		"{{AUTHOR}}", html.EscapeString(author),
+		"{{REPLY}}", html.EscapeString(msg.ReplyBody),
 		"{{LINK}}", html.EscapeString(link),
-		"{{MARK}}", "cid:answer-notification-mark",
-	).Replace(questionAnsweredHTML)
+		"{{MARK}}", "cid:reply-notification-mark",
+	).Replace(postReplyHTML)
 	return text, htmlBody
 }

-const questionAnsweredHTML = `<!doctype html>
+func replyRootTitle(title string) string {
+	title = strings.TrimSpace(title)
+	if title == "" {
+		return "your conversation"
+	}
+	return title
+}
+
+const postReplyHTML = `<!doctype html>
 <html lang="en">
 <head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <meta name="color-scheme" content="dark">
  <meta name="supported-color-schemes" content="dark">
-  <title>Your question was answered</title>
+  <title>New reply to your conversation</title>
 </head>
 <body style="margin:0;padding:0;background:#161719;color:#ecebe7;font-family:Arial,'Helvetica Neue',sans-serif;">
  <div style="display:none;max-height:0;overflow:hidden;opacity:0;color:transparent;">{{PREHEADER}}</div>
@@ -147,22 +163,22 @@ const questionAnsweredHTML = `<!doctype html>
          </tr>
          <tr>
            <td style="padding:30px 28px 32px;">
-              <div style="margin:0 0 10px;color:#e96a26;font-family:'Courier New',monospace;font-size:11px;font-weight:700;line-height:1.4;letter-spacing:1.8px;text-transform:uppercase;">Shop response</div>
-              <h1 style="margin:0;color:#ecebe7;font-size:28px;font-weight:600;line-height:1.2;letter-spacing:-0.4px;">Your question has an answer.</h1>
-              <p style="margin:18px 0 0;color:#b8babf;font-size:16px;line-height:1.6;">Hi{{GREETING}}, a plumber replied to:</p>
+              <div style="margin:0 0 10px;color:#e96a26;font-family:'Courier New',monospace;font-size:11px;font-weight:700;line-height:1.4;letter-spacing:1.8px;text-transform:uppercase;">New reply</div>
+              <h1 style="margin:0;color:#ecebe7;font-size:28px;font-weight:600;line-height:1.2;letter-spacing:-0.4px;">The conversation has a new reply.</h1>
+              <p style="margin:18px 0 0;color:#b8babf;font-size:16px;line-height:1.6;">Hi{{GREETING}}, {{AUTHOR}} replied in:</p>
              <p style="margin:8px 0 0;color:#ecebe7;font-size:17px;font-weight:600;line-height:1.45;">“{{TITLE}}”</p>
              <table role="presentation" width="100%" cellspacing="0" cellpadding="0" border="0" style="width:100%;margin-top:24px;background:#161719;border:1px solid #2e3136;border-radius:3px;">
                <tr>
                  <td style="padding:20px 18px;">
-                    <div style="margin:0 0 10px;color:#8d9096;font-family:'Courier New',monospace;font-size:10px;font-weight:700;line-height:1.4;letter-spacing:1.5px;text-transform:uppercase;">The answer</div>
-                    <div style="margin:0;color:#ecebe7;font-size:16px;line-height:1.65;white-space:pre-wrap;">{{ANSWER}}</div>
+                    <div style="margin:0 0 10px;color:#8d9096;font-family:'Courier New',monospace;font-size:10px;font-weight:700;line-height:1.4;letter-spacing:1.5px;text-transform:uppercase;">The reply</div>
+                    <div style="margin:0;color:#ecebe7;font-size:16px;line-height:1.65;white-space:pre-wrap;">{{REPLY}}</div>
                  </td>
                </tr>
              </table>
              <table role="presentation" cellspacing="0" cellpadding="0" border="0" style="margin-top:26px;">
                <tr>
                  <td bgcolor="#e96a26" style="border-radius:3px;">
-                    <a href="{{LINK}}" style="display:inline-block;padding:13px 18px;color:#161719;font-family:'Courier New',monospace;font-size:12px;font-weight:700;line-height:1;text-decoration:none;letter-spacing:0.8px;text-transform:uppercase;">View the answer&nbsp;&rarr;</a>
+                    <a href="{{LINK}}" style="display:inline-block;padding:13px 18px;color:#161719;font-family:'Courier New',monospace;font-size:12px;font-weight:700;line-height:1;text-decoration:none;letter-spacing:0.8px;text-transform:uppercase;">View the reply&nbsp;&rarr;</a>
                  </td>
                </tr>
              </table>
@@ -170,7 +186,7 @@ const questionAnsweredHTML = `<!doctype html>
          </tr>
          <tr>
            <td style="padding:18px 28px;border-top:1px solid #2e3136;color:#8d9096;font-family:'Courier New',monospace;font-size:10px;line-height:1.6;letter-spacing:0.4px;">
-              You received this because you asked a question on Ask a Plumber First.
+              You received this because someone replied to your post on Ask a Plumber First.
            </td>
          </tr>
        </table>
@@ -14,24 +14,27 @@ func TestEmbeddedMarkIsPNG(t *testing.T) {
 	}
 }

-func TestQuestionAnsweredContent(t *testing.T) {
+func TestPostReplyContent(t *testing.T) {
 	t.Parallel()

-	text, htmlBody := questionAnsweredContent("https://plumber.example/", QuestionAnswered{
-		ToName:        `<Sam & Pat>`,
-		QuestionID:    "question-123",
-		QuestionTitle: `<b>Leaky sink</b>`,
-		AnswerBody:    "Replace the cartridge.\nThen test the handle. <script>alert('x')</script>",
+	text, htmlBody := postReplyContent("https://www.askaplumberfirst.com/", PostReply{
+		ToName:          `<Sam & Pat>`,
+		RootID:          "question-123",
+		RootTitle:       `<b>Leaky sink</b>`,
+		ReplyID:         "reply-456",
+		ReplyBody:       "Replace the cartridge.\nThen test the handle. <script>alert('x')</script>",
+		ReplyAuthorName: `<Jo & Co>`,
 	})

 	for _, want := range []string{
 		"Ask a Plumber First",
-		"Shop response",
-		"cid:answer-notification-mark",
-		"https://plumber.example/questions/question-123",
+		"New reply",
+		"cid:reply-notification-mark",
+		"https://www.askaplumberfirst.com/questions/question-123#post-reply-456",
 		"white-space:pre-wrap",
 		"&lt;Sam &amp; Pat&gt;",
 		"&lt;b&gt;Leaky sink&lt;/b&gt;",
+		"&lt;Jo &amp; Co&gt;",
 		"&lt;script&gt;alert(&#39;x&#39;)&lt;/script&gt;",
 	} {
 		if !strings.Contains(htmlBody, want) {
@@ -41,6 +44,7 @@ func TestQuestionAnsweredContent(t *testing.T) {
 	for _, unsafe := range []string{
 		"<Sam & Pat>",
 		"<b>Leaky sink</b>",
+		"<Jo & Co>",
 		"<script>alert('x')</script>",
 	} {
 		if strings.Contains(htmlBody, unsafe) {
@@ -52,9 +56,9 @@ func TestQuestionAnsweredContent(t *testing.T) {
 	}
 	for _, want := range []string{
 		`Hi <Sam & Pat>,`,
-		`Your question "<b>Leaky sink</b>"`,
+		`<Jo & Co> replied in "<b>Leaky sink</b>"`,
 		"Replace the cartridge.\nThen test the handle.",
-		"https://plumber.example/questions/question-123",
+		"https://www.askaplumberfirst.com/questions/question-123#post-reply-456",
 	} {
 		if !strings.Contains(text, want) {
 			t.Errorf("text missing %q", want)
@@ -62,15 +66,15 @@ func TestQuestionAnsweredContent(t *testing.T) {
 	}
 }

-func TestQuestionAnsweredContentUsesFallbackTitle(t *testing.T) {
+func TestPostReplyContentUsesFallbacks(t *testing.T) {
 	t.Parallel()

-	text, htmlBody := questionAnsweredContent("https://plumber.example", QuestionAnswered{})
-	if !strings.Contains(text, `"your question"`) {
+	text, htmlBody := postReplyContent("https://www.askaplumberfirst.com", PostReply{})
+	if !strings.Contains(text, `Someone replied in "your conversation"`) {
 		t.Errorf("text missing fallback title")
 	}
-	if !strings.Contains(htmlBody, "a plumber replied to:</p>") ||
-		!strings.Contains(htmlBody, "“your question”") {
-		t.Errorf("HTML missing fallback title")
+	if !strings.Contains(htmlBody, "Someone replied in:</p>") ||
+		!strings.Contains(htmlBody, "“your conversation”") {
+		t.Errorf("HTML missing fallbacks")
 	}
 }
@@ -8,10 +8,10 @@ import (
 // Recording is a test Notifier that records calls.
 type Recording struct {
 	mu   sync.Mutex
-	Msgs []QuestionAnswered
+	Msgs []PostReply
 }

-func (r *Recording) NotifyQuestionAnswered(_ context.Context, msg QuestionAnswered) error {
+func (r *Recording) NotifyPostReply(_ context.Context, msg PostReply) error {
 	r.mu.Lock()
 	defer r.mu.Unlock()
 	r.Msgs = append(r.Msgs, msg)
@@ -25,10 +25,10 @@ func (r *Recording) Len() int {
 }

 // Snapshot returns a copy of recorded messages.
-func (r *Recording) Snapshot() []QuestionAnswered {
+func (r *Recording) Snapshot() []PostReply {
 	r.mu.Lock()
 	defer r.mu.Unlock()
-	out := make([]QuestionAnswered, len(r.Msgs))
+	out := make([]PostReply, len(r.Msgs))
 	copy(out, r.Msgs)
 	return out
 }