Add Discord outbound posting (#14)

Stacks on #13. Adds discord_post_links and a subscriber that posts roots into a public thread, replies into that thread, and edits the linked Discord message. Unset Discord env leaves the site unchanged.

Reviewed-on: #14
Co-authored-by: codegirl-007 <s.raide@gmail.com>

cmd/server/main.go

@@ -37,15 +37,14 @@ func main() {
 		log.Fatalf("mail: %v", err)
 	}
 	bus := events.New()
-	mail.Subscribe(bus, store.NewPostgres(db), notifier)
-	bot, err := discord.FromEnv(store.NewDiscordLinks(db), bus, store.NewPostgres(db), notifier)
+	bot, err := discord.FromEnv(store.NewDiscordLinks(db), bus)
 	if err != nil {
 		log.Fatalf("discord: %v", err)
 	}
 	if bot != nil {
 		defer bot.Close()
 	}
-	handler := newHandler(db, sessions, uploader, bus)
+	handler := newHandler(db, sessions, uploader, notifier, bus)
 	run(&http.Server{
 		Addr:              listenAddr(),
 		Handler:           handler,
@@ -69,12 +68,13 @@ func openDB() (*sql.DB, *store.SessionStore) {
 	return db, sessions
 }
 
-func newHandler(db *sql.DB, sessions *store.SessionStore, uploader blob.Uploader, bus events.Publisher) http.Handler {
+func newHandler(db *sql.DB, sessions *store.SessionStore, uploader blob.Uploader, notifier mail.Notifier, bus events.Publisher) http.Handler {
 	srv, err := web.New(store.NewPostgres(db), sessions.Store(), plumber.TemplateFS, plumber.StaticFS, web.Config{
 		AdminSetupSecret: strings.TrimSpace(os.Getenv("ADMIN_SETUP_SECRET")),
 		SecureCookie:     secureCookieFromEnv(),
 		TrustedProxies:   parseTrustedProxies(os.Getenv("TRUSTED_PROXY_CIDRS")),
 		Blob:             uploader,
+		Mail:             notifier,
 		Events:           bus,
 		BaseURL:          strings.TrimRight(strings.TrimSpace(os.Getenv("APP_BASE_URL")), "/"),
 	})

internal/discord/api.go

@@ -9,7 +9,7 @@ import (
 // API is the Discord REST surface used by the outbound subscriber.
 type API interface {
 	SendToChannel(ctx context.Context, channelID string, msg Message) (messageID string, err error)
-	StartThread(ctx context.Context, channelID, name string) (threadID string, err error)
+	StartThread(ctx context.Context, channelID, messageID, name string) (threadID string, err error)
 	SendToThread(ctx context.Context, threadID string, msg Message) (messageID string, err error)
 	Edit(ctx context.Context, channelID, messageID string, msg Message) error
 	Close() error
@@ -27,10 +27,9 @@ func (s *sessionAPI) SendToChannel(_ context.Context, channelID string, msg Mess
 	return sent.ID, nil
 }
 
-func (s *sessionAPI) StartThread(_ context.Context, channelID, name string) (string, error) {
-	thread, err := s.session.ThreadStartComplex(channelID, &discordgo.ThreadStart{
+func (s *sessionAPI) StartThread(_ context.Context, channelID, messageID, name string) (string, error) {
+	thread, err := s.session.MessageThreadStartComplex(channelID, messageID, &discordgo.ThreadStart{
 		Name:                name,
-		Type:                discordgo.ChannelTypeGuildPublicThread,
 		AutoArchiveDuration: 10080,
 	})
 	if err != nil {
@@ -44,12 +43,10 @@ func (s *sessionAPI) SendToThread(ctx context.Context, threadID string, msg Mess
 }
 
 func (s *sessionAPI) Edit(_ context.Context, channelID, messageID string, msg Message) error {
-	content := messageContent(msg)
 	embeds := toEmbeds(msg)
 	_, err := s.session.ChannelMessageEditComplex(&discordgo.MessageEdit{
 		ID:      messageID,
 		Channel: channelID,
-		Content: &content,
 		Embeds:  &embeds,
 	})
 	return err
@@ -64,7 +61,6 @@ func (s *sessionAPI) Close() error {
 
 func toMessageSend(msg Message) *discordgo.MessageSend {
 	return &discordgo.MessageSend{
-		Content:         messageContent(msg),
 		Embeds:          toEmbeds(msg),
 		AllowedMentions: &discordgo.MessageAllowedMentions{},
 	}
@@ -73,7 +69,7 @@ func toMessageSend(msg Message) *discordgo.MessageSend {
 func toEmbeds(msg Message) []*discordgo.MessageEmbed {
 	main := &discordgo.MessageEmbed{
 		Title:       msg.Title,
-		URL:         publicURL(msg.URL),
+		URL:         msg.URL,
 		Description: msg.Description,
 		Color:       embedColor,
 	}

internal/discord/bot.go

@@ -13,7 +13,6 @@ import (
 	"github.com/bwmarrin/discordgo"
 
 	"plumber/internal/events"
-	"plumber/internal/mail"
 	"plumber/internal/store"
 )
 
@@ -24,10 +23,6 @@ type Bot struct {
 	channelID string
 	links     store.DiscordLinkStore
 	api       API
-	store     store.Store
-	mail      mail.Notifier
-	admins    map[string]string
-	botUserID string
 }
 
 // New constructs an outbound subscriber. Tests inject a fake API.
@@ -36,7 +31,7 @@ func New(channelID string, links store.DiscordLinkStore, api API) *Bot {
 }
 
 // FromEnv builds a bot when Discord env is set. Missing config is a no-op.
-func FromEnv(links store.DiscordLinkStore, bus *events.Bus, st store.Store, mailer mail.Notifier) (*Bot, error) {
+func FromEnv(links store.DiscordLinkStore, bus *events.Bus) (*Bot, error) {
 	token := strings.TrimSpace(os.Getenv("DISCORD_BOT_TOKEN"))
 	channelID := strings.TrimSpace(os.Getenv("DISCORD_CHANNEL_ID"))
 	if token == "" && channelID == "" {
@@ -55,26 +50,11 @@ func FromEnv(links store.DiscordLinkStore, bus *events.Bus, st store.Store, mail
 	if err != nil {
 		return nil, err
 	}
-	session.Identify.Intents = discordgo.IntentsGuilds | discordgo.IntentsGuildMessages | discordgo.IntentsMessageContent
-	if mailer == nil {
-		mailer = mail.Nop{}
-	}
 	bot := New(channelID, links, &sessionAPI{session: session})
-	bot.store = st
-	bot.mail = mailer
-	bot.admins = parseAdminMap(os.Getenv("DISCORD_ADMIN_MAP"))
-	session.AddHandler(bot.onMessageCreate)
 	if bus != nil {
 		bus.Subscribe(bot.Handle)
 	}
-	if err := session.Open(); err != nil {
-		_ = session.Close()
-		return nil, fmt.Errorf("discord gateway: %w", err)
-	}
-	if session.State != nil && session.State.User != nil {
-		bot.botUserID = session.State.User.ID
-	}
-	log.Printf("discord: subscriber enabled")
+	log.Printf("discord: outbound subscriber enabled")
 	return bot, nil
 }
 
@@ -133,16 +113,16 @@ func (b *Bot) onUpdated(ctx context.Context, ev events.PostEvent) {
 
 func (b *Bot) createRoot(ctx context.Context, ev events.PostEvent) {
 	msg := formatMessage(ev)
-	threadID, err := b.api.StartThread(ctx, b.channelID, msg.ThreadName)
-	if err != nil {
-		log.Printf("discord: start thread %s: %v", ev.PostID, err)
-		return
-	}
-	messageID, err := b.api.SendToThread(ctx, threadID, msg)
+	messageID, err := b.api.SendToChannel(ctx, b.channelID, msg)
 	if err != nil {
 		log.Printf("discord: send root %s: %v", ev.PostID, err)
 		return
 	}
+	threadID, err := b.api.StartThread(ctx, b.channelID, messageID, msg.ThreadName)
+	if err != nil {
+		log.Printf("discord: start thread %s: %v", ev.PostID, err)
+		return
+	}
 	if err := b.links.Upsert(ctx, store.DiscordLink{
 		PostID:    ev.PostID,
 		MessageID: messageID,
@@ -185,7 +165,7 @@ func (b *Bot) createReply(ctx context.Context, ev events.PostEvent) {
 
 func (b *Bot) editChannel(ctx context.Context, ev events.PostEvent, link *store.DiscordLink) (string, error) {
 	if strings.TrimSpace(link.ThreadID) != "" {
-		return link.ThreadID, nil
+		return b.channelID, nil
 	}
 	root, err := b.links.GetByPostID(ctx, ev.RootID)
 	if err != nil {

internal/discord/bot_test.go

@@ -2,11 +2,11 @@ package discord
 
 import (
 	"context"
-	"strconv"
-	"strings"
 	"sync"
 	"testing"
 
+	"strconv"
+
 	"plumber/internal/events"
 	"plumber/internal/store"
 )
@@ -30,18 +30,17 @@ func (f *fakeAPI) SendToChannel(_ context.Context, channelID string, msg Message
 	return f.record("channel", channelID, "", msg)
 }
 
-func (f *fakeAPI) StartThread(_ context.Context, channelID, name string) (string, error) {
+func (f *fakeAPI) StartThread(_ context.Context, channelID, messageID, name string) (string, error) {
 	f.mu.Lock()
 	defer f.mu.Unlock()
 	f.next++
-	id := "thread-" + strconv.Itoa(f.next)
 	f.sends = append(f.sends, recordedSend{
 		Kind:      "thread",
 		ChannelID: channelID,
 		Name:      name,
-		Msg:       Message{ThreadName: name},
+		Msg:       Message{ThreadName: name, URL: messageID},
 	})
-	return id, nil
+	return "thread-" + messageID, nil
 }
 
 func (f *fakeAPI) SendToThread(_ context.Context, threadID string, msg Message) (string, error) {
@@ -94,21 +93,17 @@ func TestOutboundRootReplyAndEdit(t *testing.T) {
 	}
 	bot.Handle(ctx, events.PostCreated{PostEvent: root})
 
-	if len(api.sends) != 2 ||
-		api.sends[0].Kind != "thread" ||
-		api.sends[1].Kind != "thread-msg" {
+	if len(api.sends) != 2 || api.sends[0].Kind != "channel" || api.sends[1].Kind != "thread" {
 		t.Fatalf("root sends = %+v", api.sends)
 	}
-	if api.sends[0].ChannelID != "channel-1" ||
-		api.sends[0].Name != "sam asks: Leaky sink" ||
-		api.sends[1].ChannelID != "thread-1" {
+	if api.sends[0].ChannelID != "channel-1" || api.sends[1].Name != "Leaky sink" {
 		t.Fatalf("root routing = %+v", api.sends)
 	}
-	if got := api.sends[1].Msg.ImageURLs; len(got) != 2 || got[0] != "https://cdn.example/a.jpg" {
+	if got := api.sends[0].Msg.ImageURLs; len(got) != 2 || got[0] != "https://cdn.example/a.jpg" {
 		t.Fatalf("root images = %v", got)
 	}
 	link, err := links.GetByPostID(ctx, "root-1")
-	if err != nil || link.MessageID != "msg-2" || link.ThreadID != "thread-1" {
+	if err != nil || link.MessageID != "msg-1" || link.ThreadID != "thread-msg-1" {
 		t.Fatalf("root link = %+v, %v", link, err)
 	}
 
@@ -121,7 +116,7 @@ func TestOutboundRootReplyAndEdit(t *testing.T) {
 		Permalink:  "https://www.askaplumberfirst.com/questions/root-1#post-reply-1",
 	}
 	bot.Handle(ctx, events.PostCreated{PostEvent: reply})
-	if len(api.sends) != 3 || api.sends[2].Kind != "thread-msg" || api.sends[2].ChannelID != "thread-1" {
+	if len(api.sends) != 3 || api.sends[2].Kind != "thread-msg" || api.sends[2].ChannelID != "thread-msg-1" {
 		t.Fatalf("reply sends = %+v", api.sends)
 	}
 	replyLink, err := links.GetByPostID(ctx, "reply-1")
@@ -131,7 +126,7 @@ func TestOutboundRootReplyAndEdit(t *testing.T) {
 
 	root.Body = "Updated leak."
 	bot.Handle(ctx, events.PostUpdated{PostEvent: root})
-	if len(api.edits) != 1 || api.edits[0].ChannelID != "thread-1" || api.edits[0].Name != "msg-2" {
+	if len(api.edits) != 1 || api.edits[0].ChannelID != "channel-1" || api.edits[0].Name != "msg-1" {
 		t.Fatalf("root edit = %+v", api.edits)
 	}
 	if api.edits[0].Msg.Description != "Updated leak." {
@@ -140,7 +135,7 @@ func TestOutboundRootReplyAndEdit(t *testing.T) {
 
 	reply.Body = "Use a ceramic cartridge."
 	bot.Handle(ctx, events.PostUpdated{PostEvent: reply})
-	if len(api.edits) != 2 || api.edits[1].ChannelID != "thread-1" || api.edits[1].Name != "msg-3" {
+	if len(api.edits) != 2 || api.edits[1].ChannelID != "thread-msg-1" || api.edits[1].Name != "msg-3" {
 		t.Fatalf("reply edit = %+v", api.edits)
 	}
 }
@@ -195,30 +190,21 @@ func TestFormatMessage(t *testing.T) {
 		got.City != "Oakland" ||
 		got.Author != "sam" ||
 		got.URL != "https://example.com/q" ||
-		got.ThreadName != "sam asks: Leaky sink" ||
+		got.ThreadName != "Leaky sink" ||
 		len(got.ImageURLs) != 1 {
 		t.Fatalf("format = %+v", got)
 	}
 
 	reply := formatMessage(events.PostEvent{Body: "Thanks", AuthorName: ""})
-	if reply.Title != "Reply" || reply.Author != "Someone" || reply.ThreadName != "Someone asks: Question" {
+	if reply.Title != "Reply" || reply.Author != "Someone" || reply.ThreadName != "Question" {
 		t.Fatalf("reply format = %+v", reply)
 	}
-	content := messageContent(got)
-	if strings.Contains(content, "Leaky sink") ||
-		!strings.Contains(content, "It drips.") ||
-		!strings.Contains(content, "Oakland") {
-		t.Fatalf("content = %q", content)
-	}
-	if publicURL("/questions/x") != "" || publicURL("http://localhost:8080/q") != "" {
-		t.Fatal("localhost or relative permalink should not be an embed URL")
-	}
 }
 
 func TestFromEnvDisabled(t *testing.T) {
 	t.Setenv("DISCORD_BOT_TOKEN", "")
 	t.Setenv("DISCORD_CHANNEL_ID", "")
-	bot, err := FromEnv(newMemoryLinks(), nil, nil, nil)
+	bot, err := FromEnv(newMemoryLinks(), nil)
 	if err != nil || bot != nil {
 		t.Fatalf("disabled FromEnv = (%v, %v)", bot, err)
 	}
@@ -227,12 +213,12 @@ func TestFromEnvDisabled(t *testing.T) {
 func TestFromEnvRequiresBoth(t *testing.T) {
 	t.Setenv("DISCORD_BOT_TOKEN", "token")
 	t.Setenv("DISCORD_CHANNEL_ID", "")
-	if _, err := FromEnv(newMemoryLinks(), nil, nil, nil); err == nil {
+	if _, err := FromEnv(newMemoryLinks(), nil); err == nil {
 		t.Fatal("expected error when channel is missing")
 	}
 	t.Setenv("DISCORD_BOT_TOKEN", "")
 	t.Setenv("DISCORD_CHANNEL_ID", "channel")
-	if _, err := FromEnv(newMemoryLinks(), nil, nil, nil); err == nil {
+	if _, err := FromEnv(newMemoryLinks(), nil); err == nil {
 		t.Fatal("expected error when token is missing")
 	}
 }

internal/discord/format.go

@@ -39,7 +39,7 @@ func formatMessage(ev events.PostEvent) Message {
 		Description: truncateRunes(strings.TrimSpace(ev.Body), embedDescriptionLimit),
 		City:        strings.TrimSpace(ev.City),
 		Author:      author,
-		ThreadName:  threadName(author, ev.Title),
+		ThreadName:  threadName(ev.Title),
 	}
 	for _, img := range ev.Images {
 		url := strings.TrimSpace(img.URL)
@@ -51,16 +51,12 @@ func formatMessage(ev events.PostEvent) Message {
 	return msg
 }
 
-func threadName(author, title string) string {
-	author = strings.TrimSpace(author)
-	if author == "" {
-		author = "Someone"
-	}
+func threadName(title string) string {
 	title = strings.TrimSpace(title)
 	if title == "" {
-		title = "Question"
+		return "Question"
 	}
-	return truncateRunes(author+" asks: "+title, threadNameLimit)
+	return truncateRunes(title, threadNameLimit)
 }
 
 func truncateRunes(s string, max int) string {
@@ -77,35 +73,3 @@ func truncateRunes(s string, max int) string {
 func isRoot(ev events.PostEvent) bool {
 	return strings.TrimSpace(ev.ParentID) == ""
 }
-
-func messageContent(msg Message) string {
-	var parts []string
-	if body := strings.TrimSpace(msg.Description); body != "" {
-		parts = append(parts, body)
-	}
-	var meta []string
-	if msg.City != "" {
-		meta = append(meta, msg.City)
-	}
-	if msg.Author != "" {
-		meta = append(meta, msg.Author)
-	}
-	if len(meta) > 0 {
-		parts = append(parts, strings.Join(meta, " · "))
-	}
-	if u := publicURL(msg.URL); u != "" {
-		parts = append(parts, u)
-	}
-	return truncateRunes(strings.Join(parts, "\n"), 2000)
-}
-
-func publicURL(raw string) string {
-	raw = strings.TrimSpace(raw)
-	if !strings.HasPrefix(raw, "https://") {
-		return ""
-	}
-	if strings.Contains(raw, "localhost") || strings.Contains(raw, "127.0.0.1") {
-		return ""
-	}
-	return raw
-}

internal/discord/inbound.go

@@ -1,227 +0,0 @@
-package discord
-
-import (
-	"context"
-	"database/sql"
-	"errors"
-	"fmt"
-	"log"
-	"strings"
-	"time"
-
-	"github.com/bwmarrin/discordgo"
-
-	"plumber/internal/mail"
-	"plumber/internal/store"
-)
-
-const inboundBodyLimit = 12000
-
-type inboundMessage struct {
-	ID                  string
-	ChannelID           string
-	GuildID             string
-	AuthorID            string
-	Content             string
-	ReferencedMessageID string
-	Bot                 bool
-	Attachments         int
-}
-
-func parseAdminMap(raw string) map[string]string {
-	out := map[string]string{}
-	for _, part := range strings.Split(raw, ",") {
-		part = strings.TrimSpace(part)
-		if part == "" {
-			continue
-		}
-		id, username, ok := strings.Cut(part, ":")
-		id = strings.TrimSpace(id)
-		username = store.NormalizeUsername(username)
-		if !ok || id == "" || username == "" {
-			log.Printf("discord: skip invalid DISCORD_ADMIN_MAP entry %q", part)
-			continue
-		}
-		out[id] = username
-	}
-	return out
-}
-
-func (b *Bot) onMessageCreate(_ *discordgo.Session, m *discordgo.MessageCreate) {
-	if b == nil || m == nil || m.Author == nil {
-		return
-	}
-	in := inboundMessage{
-		ID:          m.ID,
-		ChannelID:   m.ChannelID,
-		GuildID:     m.GuildID,
-		AuthorID:    m.Author.ID,
-		Content:     m.Content,
-		Bot:         m.Author.Bot,
-		Attachments: len(m.Attachments),
-	}
-	if m.MessageReference != nil {
-		in.ReferencedMessageID = m.MessageReference.MessageID
-	}
-	b.handleInbound(in)
-}
-
-func (b *Bot) handleInbound(in inboundMessage) {
-	if b == nil || b.store == nil {
-		return
-	}
-	if in.Bot || strings.TrimSpace(in.GuildID) == "" {
-		return
-	}
-	if b.botUserID != "" && in.AuthorID == b.botUserID {
-		return
-	}
-	body := strings.TrimSpace(in.Content)
-	if in.Attachments > 0 {
-		log.Printf("discord: ignoring %d attachment(s) on %s", in.Attachments, in.ID)
-	}
-	if body == "" {
-		return
-	}
-	ctx, cancel := context.WithTimeout(context.Background(), discordTimeout)
-	defer cancel()
-	if !b.knownChannel(ctx, in.ChannelID) {
-		return
-	}
-	username := b.admins[in.AuthorID]
-	if username == "" {
-		return
-	}
-	author, err := b.store.UserByUsername(ctx, username)
-	if err != nil {
-		if !errors.Is(err, sql.ErrNoRows) {
-			log.Printf("discord: inbound author %s: %v", username, err)
-		}
-		return
-	}
-	if !author.Admin() {
-		log.Printf("discord: inbound %s is not an admin", username)
-		return
-	}
-	parent, root, err := b.inboundParent(ctx, in)
-	if err != nil {
-		if !errors.Is(err, sql.ErrNoRows) {
-			log.Printf("discord: inbound parent %s: %v", in.ID, err)
-		}
-		return
-	}
-	if root.PostState == store.PostStateHidden {
-		return
-	}
-	reply := &store.Post{
-		AuthorID: author.ID,
-		Body:     truncateRunes(body, inboundBodyLimit),
-		ParentID: &parent.ID,
-	}
-	if err := b.store.CreatePost(ctx, reply); err != nil {
-		log.Printf("discord: create inbound %s: %v", in.ID, err)
-		return
-	}
-	if err := b.links.Upsert(ctx, store.DiscordLink{
-		PostID:    reply.ID,
-		MessageID: in.ID,
-	}); err != nil {
-		log.Printf("discord: save inbound link %s: %v", reply.ID, err)
-	}
-	b.notifyInboundReply(parent, root, reply, author)
-	log.Printf("discord: inbound reply %s -> post %s", in.ID, reply.ID)
-}
-
-func (b *Bot) knownChannel(ctx context.Context, channelID string) bool {
-	if strings.TrimSpace(channelID) == "" {
-		return false
-	}
-	if channelID == b.channelID {
-		return true
-	}
-	_, err := b.links.GetRootByThreadID(ctx, channelID)
-	return err == nil
-}
-
-func (b *Bot) inboundParent(ctx context.Context, in inboundMessage) (*store.Post, *store.Post, error) {
-	if ref := strings.TrimSpace(in.ReferencedMessageID); ref != "" {
-		link, err := b.links.GetByMessageID(ctx, ref)
-		if err == nil {
-			return b.postAndRoot(ctx, link.PostID)
-		}
-		if !errors.Is(err, sql.ErrNoRows) {
-			return nil, nil, err
-		}
-	}
-	link, err := b.links.GetRootByThreadID(ctx, in.ChannelID)
-	if err != nil {
-		return nil, nil, err
-	}
-	return b.postAndRoot(ctx, link.PostID)
-}
-
-func (b *Bot) postAndRoot(ctx context.Context, postID string) (*store.Post, *store.Post, error) {
-	postID = strings.TrimSpace(postID)
-	if postID == "" {
-		return nil, nil, sql.ErrNoRows
-	}
-	post, err := b.store.GetPost(ctx, postID)
-	if err != nil {
-		return nil, nil, err
-	}
-	current := post
-	seen := map[string]bool{}
-	for current.ParentID != nil {
-		if seen[current.ID] {
-			return nil, nil, fmt.Errorf("post ancestry cycle at %s", current.ID)
-		}
-		seen[current.ID] = true
-		current, err = b.store.GetPost(ctx, *current.ParentID)
-		if err != nil {
-			return nil, nil, err
-		}
-	}
-	return post, current, nil
-}
-
-func (b *Bot) notifyInboundReply(parent, root, reply *store.Post, author *store.User) {
-	if parent == nil || root == nil || reply == nil || author == nil || b.mail == nil {
-		return
-	}
-	if _, disabled := b.mail.(mail.Nop); disabled {
-		return
-	}
-	recipientID := parent.AuthorID
-	if author.Admin() {
-		recipientID = root.AuthorID
-	}
-	if recipientID == author.ID {
-		return
-	}
-	msg := mail.PostReply{
-		RootID:          root.ID,
-		RootTitle:       root.Title,
-		ReplyID:         reply.ID,
-		ReplyBody:       reply.Body,
-		ReplyAuthorName: author.Name,
-	}
-	go func() {
-		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
-		defer cancel()
-		recipient, err := b.store.UserByID(ctx, recipientID)
-		if err != nil {
-			log.Printf("notify reply %s: load recipient: %v", msg.ReplyID, err)
-			return
-		}
-		if recipient == nil || strings.TrimSpace(recipient.Email) == "" {
-			return
-		}
-		msg.ToEmail = recipient.Email
-		msg.ToName = recipient.Name
-		if err := b.mail.NotifyPostReply(ctx, msg); err != nil {
-			log.Printf("notify reply %s: %v", msg.ReplyID, err)
-			return
-		}
-		log.Printf("notify reply %s: accepted", msg.ReplyID)
-	}()
-}

internal/discord/inbound_test.go

@@ -1,218 +0,0 @@
-package discord
-
-import (
-	"context"
-	"testing"
-	"time"
-
-	"plumber/internal/events"
-	"plumber/internal/mail"
-	"plumber/internal/pacific"
-	"plumber/internal/store"
-)
-
-func TestParseAdminMap(t *testing.T) {
-	t.Parallel()
-
-	got := parseAdminMap(" 123:Plumber ,456:other,bad, :empty,789: ")
-	if got["123"] != "plumber" || got["456"] != "other" || len(got) != 2 {
-		t.Fatalf("parseAdminMap = %#v", got)
-	}
-}
-
-func TestInboundCreatesSiteReply(t *testing.T) {
-	t.Parallel()
-
-	mem, homeowner, admin := seedInboundUsers(t)
-	links := newMemoryLinks()
-	api := &fakeAPI{}
-	mailer := &mail.Recording{}
-	bot := inboundTestBot(mem, links, api, mailer, admin.Username)
-	bus := events.New()
-	defer bus.Close()
-	bus.Subscribe(bot.Handle)
-	root := seedLinkedRoot(t, mem, links, homeowner.ID, "thread-1")
-
-	bot.handleInbound(inboundMessage{
-		ID:        "d-reply-1",
-		ChannelID: "thread-1",
-		GuildID:   "guild-1",
-		AuthorID:  "snow-admin",
-		Content:   "Replace the cartridge.",
-	})
-
-	thread, err := mem.GetPostThread(context.Background(), root.ID)
-	if err != nil || len(thread.Replies) != 1 {
-		t.Fatalf("thread = %+v, %v", thread, err)
-	}
-	reply := thread.Replies[0]
-	if reply.AuthorID != admin.ID || reply.Body != "Replace the cartridge." || reply.ParentID == nil || *reply.ParentID != root.ID {
-		t.Fatalf("reply = %+v", reply)
-	}
-	link, err := links.GetByPostID(context.Background(), reply.ID)
-	if err != nil || link.MessageID != "d-reply-1" || link.ThreadID != "" {
-		t.Fatalf("inbound link = %+v, %v", link, err)
-	}
-	time.Sleep(20 * time.Millisecond)
-	if len(api.sends) != 0 || len(api.edits) != 0 {
-		t.Fatalf("inbound echoed to Discord: sends=%+v edits=%+v", api.sends, api.edits)
-	}
-	msgs := waitForMail(t, mailer, 1)
-	if msgs[0].ToEmail != homeowner.Email || msgs[0].ReplyID != reply.ID || msgs[0].RootID != root.ID {
-		t.Fatalf("mail = %+v", msgs[0])
-	}
-}
-
-func TestInboundParentsFromReference(t *testing.T) {
-	t.Parallel()
-
-	mem, homeowner, admin := seedInboundUsers(t)
-	links := newMemoryLinks()
-	bot := inboundTestBot(mem, links, &fakeAPI{}, &mail.Recording{}, admin.Username)
-	root := seedLinkedRoot(t, mem, links, homeowner.ID, "thread-1")
-	plumberReply := &store.Post{ParentID: &root.ID, AuthorID: admin.ID, Body: "First look."}
-	if err := mem.CreatePost(context.Background(), plumberReply); err != nil {
-		t.Fatal(err)
-	}
-	if err := links.Upsert(context.Background(), store.DiscordLink{
-		PostID:    plumberReply.ID,
-		MessageID: "d-plumber-1",
-	}); err != nil {
-		t.Fatal(err)
-	}
-
-	bot.handleInbound(inboundMessage{
-		ID:                  "d-nested",
-		ChannelID:           "thread-1",
-		GuildID:             "guild-1",
-		AuthorID:            "snow-admin",
-		Content:             "More detail.",
-		ReferencedMessageID: "d-plumber-1",
-	})
-
-	thread, err := mem.GetPostThread(context.Background(), root.ID)
-	if err != nil || len(thread.Replies) != 1 || len(thread.Replies[0].Replies) != 1 {
-		t.Fatalf("thread = %+v, %v", thread, err)
-	}
-	nested := thread.Replies[0].Replies[0]
-	if nested.ParentID == nil || *nested.ParentID != plumberReply.ID {
-		t.Fatalf("nested parent = %+v", nested)
-	}
-}
-
-func TestInboundIgnoresAllowlistHiddenAndEchoSources(t *testing.T) {
-	t.Parallel()
-
-	mem, homeowner, admin := seedInboundUsers(t)
-	links := newMemoryLinks()
-	api := &fakeAPI{}
-	bot := inboundTestBot(mem, links, api, mail.Nop{}, admin.Username)
-	root := seedLinkedRoot(t, mem, links, homeowner.ID, "thread-1")
-	hidden := &store.Post{
-		AuthorID:  homeowner.ID,
-		Title:     "Hidden",
-		Body:      "No.",
-		PostDate:  pacific.Today(),
-		PostState: store.PostStateHidden,
-	}
-	if err := mem.CreatePost(context.Background(), hidden); err != nil {
-		t.Fatal(err)
-	}
-	if err := links.Upsert(context.Background(), store.DiscordLink{
-		PostID:    hidden.ID,
-		MessageID: "d-hidden",
-		ThreadID:  "thread-hidden",
-	}); err != nil {
-		t.Fatal(err)
-	}
-
-	cases := []inboundMessage{
-		{ID: "bot", ChannelID: "thread-1", GuildID: "g", AuthorID: "snow-admin", Content: "x", Bot: true},
-		{ID: "dm", ChannelID: "thread-1", AuthorID: "snow-admin", Content: "x"},
-		{ID: "self", ChannelID: "thread-1", GuildID: "g", AuthorID: "bot-1", Content: "x"},
-		{ID: "stranger", ChannelID: "thread-1", GuildID: "g", AuthorID: "snow-other", Content: "x"},
-		{ID: "elsewhere", ChannelID: "other-thread", GuildID: "g", AuthorID: "snow-admin", Content: "x"},
-		{ID: "empty", ChannelID: "thread-1", GuildID: "g", AuthorID: "snow-admin", Content: "   ", Attachments: 1},
-		{ID: "hidden", ChannelID: "thread-hidden", GuildID: "g", AuthorID: "snow-admin", Content: "x"},
-		{ID: "channel-root", ChannelID: "channel-1", GuildID: "g", AuthorID: "snow-admin", Content: "new question"},
-	}
-	for _, in := range cases {
-		bot.handleInbound(in)
-	}
-	thread, err := mem.GetPostThread(context.Background(), root.ID)
-	if err != nil || len(thread.Replies) != 0 {
-		t.Fatalf("unexpected replies: %+v, %v", thread, err)
-	}
-	if len(api.sends) != 0 {
-		t.Fatalf("unexpected discord sends %+v", api.sends)
-	}
-}
-
-func inboundTestBot(mem *store.Memory, links *memoryLinks, api *fakeAPI, mailer mail.Notifier, adminUsername string) *Bot {
-	bot := New("channel-1", links, api)
-	bot.store = mem
-	bot.mail = mailer
-	bot.admins = map[string]string{"snow-admin": adminUsername}
-	bot.botUserID = "bot-1"
-	return bot
-}
-
-func seedInboundUsers(t *testing.T) (*store.Memory, *store.User, *store.User) {
-	t.Helper()
-	mem := store.NewMemory()
-	homeowner := &store.User{
-		Username:     "homeowner",
-		Name:         "Sam",
-		Email:        "sam@example.com",
-		PasswordHash: "x",
-		Role:         store.RoleUser,
-	}
-	if err := mem.CreateUser(context.Background(), homeowner); err != nil {
-		t.Fatal(err)
-	}
-	admin := &store.User{
-		Username:     "plumber",
-		Name:         "Pat",
-		Email:        "pat@example.com",
-		PasswordHash: "x",
-		Role:         store.RoleAdmin,
-	}
-	if err := mem.CreateUser(context.Background(), admin); err != nil {
-		t.Fatal(err)
-	}
-	return mem, homeowner, admin
-}
-
-func seedLinkedRoot(t *testing.T, mem *store.Memory, links *memoryLinks, authorID, threadID string) *store.Post {
-	t.Helper()
-	root := &store.Post{
-		AuthorID: authorID,
-		Title:    "Leaky sink",
-		Body:     "It drips.",
-		PostDate: pacific.Today(),
-	}
-	if err := mem.CreatePost(context.Background(), root); err != nil {
-		t.Fatal(err)
-	}
-	if err := links.Upsert(context.Background(), store.DiscordLink{
-		PostID:    root.ID,
-		MessageID: "d-root",
-		ThreadID:  threadID,
-	}); err != nil {
-		t.Fatal(err)
-	}
-	return root
-}
-
-func waitForMail(t *testing.T, recording *mail.Recording, want int) []mail.PostReply {
-	t.Helper()
-	deadline := time.Now().Add(2 * time.Second)
-	for time.Now().Before(deadline) {
-		if recording.Len() >= want {
-			return recording.Snapshot()
-		}
-		time.Sleep(10 * time.Millisecond)
-	}
-	t.Fatalf("recorded %d notifications, want %d", recording.Len(), want)
-	return nil
-}

internal/mail/subscriber.go

@@ -1,89 +0,0 @@
-package mail
-
-import (
-	"context"
-	"log"
-	"strings"
-	"time"
-
-	"plumber/internal/events"
-	"plumber/internal/store"
-)
-
-// Subscribe sends reply emails from PostCreated events. Nop or nil is a no-op.
-func Subscribe(bus *events.Bus, st store.Store, n Notifier) {
-	if bus == nil || st == nil || n == nil {
-		return
-	}
-	if _, disabled := n.(Nop); disabled {
-		return
-	}
-	s := subscriber{store: st, mail: n}
-	bus.Subscribe(s.handle)
-}
-
-type subscriber struct {
-	store store.Store
-	mail  Notifier
-}
-
-func (s subscriber) handle(_ context.Context, ev any) {
-	created, ok := ev.(events.PostCreated)
-	if !ok {
-		return
-	}
-	if strings.TrimSpace(created.ParentID) == "" {
-		return
-	}
-	go s.notifyReply(created.PostEvent)
-}
-
-func (s subscriber) notifyReply(ev events.PostEvent) {
-	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
-	defer cancel()
-
-	parent, err := s.store.GetPost(ctx, ev.ParentID)
-	if err != nil {
-		log.Printf("notify reply %s: load parent: %v", ev.PostID, err)
-		return
-	}
-	root, err := s.store.GetPost(ctx, ev.RootID)
-	if err != nil {
-		log.Printf("notify reply %s: load root: %v", ev.PostID, err)
-		return
-	}
-	author, err := s.store.UserByID(ctx, ev.AuthorID)
-	if err != nil {
-		log.Printf("notify reply %s: load author: %v", ev.PostID, err)
-		return
-	}
-	recipientID := parent.AuthorID
-	if author.Admin() {
-		recipientID = root.AuthorID
-	}
-	if recipientID == author.ID {
-		return
-	}
-	msg := PostReply{
-		RootID:          root.ID,
-		RootTitle:       root.Title,
-		ReplyID:         ev.PostID,
-		ReplyBody:       ev.Body,
-		ReplyAuthorName: author.Name,
-	}
-	recipient, err := s.store.UserByID(ctx, recipientID)
-	if err != nil {
-		log.Printf("notify reply %s: load recipient: %v", msg.ReplyID, err)
-		return
-	}
-	if recipient == nil || strings.TrimSpace(recipient.Email) == "" {
-		return
-	}
-	msg.ToEmail = recipient.Email
-	msg.ToName = recipient.Name
-	if err := s.mail.NotifyPostReply(ctx, msg); err != nil {
-		log.Printf("notify reply %s: %v", msg.ReplyID, err)
-		return
-	}
-	log.Printf("notify reply %s: accepted", msg.ReplyID)
-}

internal/mail/subscriber_test.go

@@ -1,200 +0,0 @@
-package mail
-
-import (
-	"context"
-	"testing"
-	"time"
-
-	"plumber/internal/events"
-	"plumber/internal/pacific"
-	"plumber/internal/store"
-)
-
-func TestSubscribeReplyNotifications(t *testing.T) {
-	t.Parallel()
-
-	mem := store.NewMemory()
-	homeowner := seedMailUser(t, mem, "homeowner", store.RoleUser, "sam@example.com")
-	admin := seedMailUser(t, mem, "plumber", store.RoleAdmin, "pat@example.com")
-	root := seedMailRoot(t, mem, homeowner.ID, "Leaky sink", "It drips.")
-	adminReply := seedMailReply(t, mem, admin.ID, root.ID)
-	homeownerReply := seedMailReply(t, mem, homeowner.ID, adminReply.ID)
-
-	bus := events.New()
-	defer bus.Close()
-	recording := &Recording{}
-	Subscribe(bus, mem, recording)
-
-	ctx := context.Background()
-	bus.Publish(ctx, events.PostCreated{PostEvent: events.PostEvent{
-		PostID:   root.ID,
-		RootID:   root.ID,
-		Title:    root.Title,
-		Body:     root.Body,
-		AuthorID: homeowner.ID,
-	}})
-	bus.Publish(ctx, events.PostUpdated{PostEvent: events.PostEvent{
-		PostID:   adminReply.ID,
-		RootID:   root.ID,
-		ParentID: root.ID,
-		Body:     "Edited",
-		AuthorID: admin.ID,
-	}})
-
-	bus.Publish(ctx, events.PostCreated{PostEvent: events.PostEvent{
-		PostID:   adminReply.ID,
-		RootID:   root.ID,
-		ParentID: root.ID,
-		Body:     adminReply.Body,
-		AuthorID: admin.ID,
-	}})
-	msgs := waitForMail(t, recording, 1)
-	if msg := msgs[0]; msg.ToEmail != homeowner.Email ||
-		msg.RootID != root.ID ||
-		msg.RootTitle != root.Title ||
-		msg.ReplyID != adminReply.ID ||
-		msg.ReplyBody != adminReply.Body ||
-		msg.ReplyAuthorName != admin.Name {
-		t.Fatalf("admin reply = %+v", msg)
-	}
-
-	bus.Publish(ctx, events.PostCreated{PostEvent: events.PostEvent{
-		PostID:   homeownerReply.ID,
-		RootID:   root.ID,
-		ParentID: adminReply.ID,
-		Body:     homeownerReply.Body,
-		AuthorID: homeowner.ID,
-	}})
-	msgs = waitForMail(t, recording, 2)
-	if msg := msgs[1]; msg.ToEmail != admin.Email ||
-		msg.RootID != root.ID ||
-		msg.ReplyID != homeownerReply.ID ||
-		msg.ReplyAuthorName != homeowner.Name {
-		t.Fatalf("homeowner reply = %+v", msg)
-	}
-
-	nestedAdmin := seedMailReply(t, mem, admin.ID, adminReply.ID)
-	bus.Publish(ctx, events.PostCreated{PostEvent: events.PostEvent{
-		PostID:   nestedAdmin.ID,
-		RootID:   root.ID,
-		ParentID: adminReply.ID,
-		Body:     nestedAdmin.Body,
-		AuthorID: admin.ID,
-	}})
-	msgs = waitForMail(t, recording, 3)
-	if msg := msgs[2]; msg.ToEmail != homeowner.Email ||
-		msg.RootID != root.ID ||
-		msg.ReplyBody != nestedAdmin.Body ||
-		msg.ReplyAuthorName != admin.Name {
-		t.Fatalf("nested admin reply = %+v", msg)
-	}
-
-	self := seedMailReply(t, mem, homeowner.ID, root.ID)
-	bus.Publish(ctx, events.PostCreated{PostEvent: events.PostEvent{
-		PostID:   self.ID,
-		RootID:   root.ID,
-		ParentID: root.ID,
-		Body:     self.Body,
-		AuthorID: homeowner.ID,
-	}})
-
-	noEmail := seedMailUser(t, mem, "quiet", store.RoleUser, "")
-	quietRoot := seedMailRoot(t, mem, noEmail.ID, "Quiet thread", "No email.")
-	quietReply := seedMailReply(t, mem, admin.ID, quietRoot.ID)
-	bus.Publish(ctx, events.PostCreated{PostEvent: events.PostEvent{
-		PostID:   quietReply.ID,
-		RootID:   quietRoot.ID,
-		ParentID: quietRoot.ID,
-		Body:     quietReply.Body,
-		AuthorID: admin.ID,
-	}})
-
-	time.Sleep(50 * time.Millisecond)
-	if recording.Len() != 3 {
-		t.Fatalf("self, root, edit, or no-email sent mail: %+v", recording.Snapshot())
-	}
-}
-
-func TestSubscribeNopIgnoresReplies(t *testing.T) {
-	t.Parallel()
-
-	mem := store.NewMemory()
-	homeowner := seedMailUser(t, mem, "homeowner", store.RoleUser, "sam@example.com")
-	admin := seedMailUser(t, mem, "plumber", store.RoleAdmin, "pat@example.com")
-	root := seedMailRoot(t, mem, homeowner.ID, "Leaky sink", "It drips.")
-	reply := seedMailReply(t, mem, admin.ID, root.ID)
-
-	bus := events.New()
-	defer bus.Close()
-	recording := &Recording{}
-	Subscribe(bus, mem, Nop{})
-	Subscribe(nil, mem, recording)
-	Subscribe(bus, mem, nil)
-
-	bus.Publish(context.Background(), events.PostCreated{PostEvent: events.PostEvent{
-		PostID:   reply.ID,
-		RootID:   root.ID,
-		ParentID: root.ID,
-		Body:     reply.Body,
-		AuthorID: admin.ID,
-	}})
-	time.Sleep(50 * time.Millisecond)
-	if recording.Len() != 0 {
-		t.Fatalf("Nop or nil subscribe sent mail: %+v", recording.Snapshot())
-	}
-}
-
-func seedMailUser(t *testing.T, mem *store.Memory, username string, role store.Role, email string) *store.User {
-	t.Helper()
-	u := &store.User{
-		Username:     username,
-		Name:         username,
-		Email:        email,
-		PasswordHash: "x",
-		Role:         role,
-	}
-	if err := mem.CreateUser(context.Background(), u); err != nil {
-		t.Fatal(err)
-	}
-	return u
-}
-
-func seedMailRoot(t *testing.T, mem *store.Memory, authorID, title, body string) *store.Post {
-	t.Helper()
-	root := &store.Post{
-		AuthorID: authorID,
-		Title:    title,
-		Body:     body,
-		PostDate: pacific.Today(),
-	}
-	if err := mem.CreatePost(context.Background(), root); err != nil {
-		t.Fatal(err)
-	}
-	return root
-}
-
-func seedMailReply(t *testing.T, mem *store.Memory, authorID, parentID string) *store.Post {
-	t.Helper()
-	reply := &store.Post{
-		ParentID: &parentID,
-		AuthorID: authorID,
-		Body:     "Reply from " + authorID,
-	}
-	if err := mem.CreatePost(context.Background(), reply); err != nil {
-		t.Fatal(err)
-	}
-	return reply
-}
-
-func waitForMail(t *testing.T, recording *Recording, want int) []PostReply {
-	t.Helper()
-	deadline := time.Now().Add(2 * time.Second)
-	for time.Now().Before(deadline) {
-		if recording.Len() >= want {
-			return recording.Snapshot()
-		}
-		time.Sleep(10 * time.Millisecond)
-	}
-	t.Fatalf("recorded %d notifications, want %d", recording.Len(), want)
-	return nil
-}

internal/web/posts.go

@@ -5,12 +5,15 @@ import (
 	"database/sql"
 	"errors"
 	"fmt"
+	"log"
 	"net/http"
 	"net/url"
 	"strings"
+	"time"
 
 	"github.com/go-chi/chi/v5"
 
+	"plumber/internal/mail"
 	"plumber/internal/store"
 )
 
@@ -79,6 +82,9 @@ func (s *Server) handleCreatePost(w http.ResponseWriter, r *http.Request) {
 	if root == nil {
 		root = post
 	}
+	if parent != nil {
+		s.notifyPostReply(parent, root, post, user)
+	}
 	s.publishPostCreated(post, root, user)
 	http.Redirect(
 		w,
@@ -88,6 +94,59 @@ func (s *Server) handleCreatePost(w http.ResponseWriter, r *http.Request) {
 	)
 }
 
+// notifyPostReply emails the root homeowner for admin replies and the direct
+// parent author for homeowner replies.
+func (s *Server) notifyPostReply(
+	parent *store.Post,
+	root *store.Post,
+	reply *store.Post,
+	replyAuthor *store.User,
+) {
+	if parent == nil ||
+		root == nil ||
+		reply == nil ||
+		replyAuthor == nil ||
+		s.cfg.Mail == nil {
+		return
+	}
+	if _, disabled := s.cfg.Mail.(mail.Nop); disabled {
+		return
+	}
+	recipientID := parent.AuthorID
+	if replyAuthor.Admin() {
+		recipientID = root.AuthorID
+	}
+	if recipientID == replyAuthor.ID {
+		return
+	}
+	msg := mail.PostReply{
+		RootID:          root.ID,
+		RootTitle:       root.Title,
+		ReplyID:         reply.ID,
+		ReplyBody:       reply.Body,
+		ReplyAuthorName: replyAuthor.Name,
+	}
+	go func() {
+		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+		defer cancel()
+		recipient, err := s.store.UserByID(ctx, recipientID)
+		if err != nil {
+			log.Printf("notify reply %s: load recipient: %v", msg.ReplyID, err)
+			return
+		}
+		if recipient == nil || strings.TrimSpace(recipient.Email) == "" {
+			return
+		}
+		msg.ToEmail = recipient.Email
+		msg.ToName = recipient.Name
+		if err := s.cfg.Mail.NotifyPostReply(ctx, msg); err != nil {
+			log.Printf("notify reply %s: %v", msg.ReplyID, err)
+			return
+		}
+		log.Printf("notify reply %s: accepted", msg.ReplyID)
+	}()
+}
+
 // handleEditPost updates only a post's body after verifying that the current
 // homeowner owns it or that an admin is editing an admin-authored post.
 func (s *Server) handleEditPost(w http.ResponseWriter, r *http.Request) {

internal/web/posts_test.go

@@ -9,7 +9,6 @@ import (
 	"testing"
 	"time"
 
-	"plumber/internal/events"
 	"plumber/internal/mail"
 	"plumber/internal/pacific"
 	"plumber/internal/store"
@@ -264,12 +263,8 @@ func TestEditPostRoutePermissions(t *testing.T) {
 func TestPostReplyNotifications(t *testing.T) {
 	t.Parallel()
 
-	mem := store.NewMemory()
-	bus := events.New()
-	defer bus.Close()
 	recording := &mail.Recording{}
-	mail.Subscribe(bus, mem, recording)
-	srv := newTestServerStore(t, mem, Config{Events: bus})
+	srv, mem := newTestServer(t, Config{Mail: recording})
 	handler := srv.Handler()
 	homeowner := seedUser(t, mem, uniq("homeowner"), "hunter22", store.RoleUser)
 	admin := seedUser(t, mem, uniq("admin"), "hunter22", store.RoleAdmin)

internal/web/server.go

@@ -22,6 +22,7 @@ import (
 	"plumber/internal/blob"
 	"plumber/internal/events"
 	"plumber/internal/geo"
+	"plumber/internal/mail"
 	"plumber/internal/pacific"
 	"plumber/internal/store"
 )
@@ -34,6 +35,7 @@ type Config struct {
 	// TrustedProxies are CIDRs allowed to set X-Forwarded-For (direct peer).
 	TrustedProxies []*net.IPNet
 	Blob           blob.Uploader
+	Mail           mail.Notifier
 	Events         events.Publisher
 	BaseURL        string
 }
@@ -108,6 +110,9 @@ func New(st store.Store, sessionStore scs.Store, templateFS fs.FS, staticFS fs.F
 	if cfg.Blob == nil {
 		cfg.Blob = blob.Disabled{}
 	}
+	if cfg.Mail == nil {
+		cfg.Mail = mail.Nop{}
+	}
 	if cfg.Events == nil {
 		cfg.Events = events.Nop{}
 	}