remove chat functionality completely

11 files changed, 4 insertions, 1330 deletions

diff --git a/srv/default.nix b/srv/default.nix
index 6bae2a8..95f35c5 100644
--- a/srv/default.nix
+++ b/srv/default.nix
@@ -38,7 +38,7 @@
         pname = "mediocre-blog-srv";
         version = "dev";
         src = ./src;
-        vendorSha256 = "sha256-C3hyPDO+6oTUeoGP/ZzBn5Y4V/q1jI12BwkR9NADHn0=";
+        vendorSha256 = "sha256:0kad8cyg9cd9v7m9l23jf27vkb5yfy9w89xfyrsyj7gd3q0l2yxq";
 
         # disable tests
         checkPhase = '''';
diff --git a/srv/src/chat/chat.go b/srv/src/chat/chat.go
deleted file mode 100644
index 0a88d3b..0000000
--- a/srv/src/chat/chat.go
+++ /dev/null
@@ -1,467 +0,0 @@
-// Package chat implements a simple chatroom system.
-package chat
-
-import (
-	"context"
-	"encoding/json"
-	"errors"
-	"fmt"
-	"strconv"
-	"sync"
-	"time"
-
-	"github.com/mediocregopher/mediocre-go-lib/v2/mctx"
-	"github.com/mediocregopher/mediocre-go-lib/v2/mlog"
-	"github.com/mediocregopher/radix/v4"
-)
-
-// ErrInvalidArg is returned from methods in this package when a call fails due
-// to invalid input.
-type ErrInvalidArg struct {
-	Err error
-}
-
-func (e ErrInvalidArg) Error() string {
-	return fmt.Sprintf("invalid argument: %v", e.Err)
-}
-
-var (
-	errInvalidMessageID = ErrInvalidArg{Err: errors.New("invalid Message ID")}
-)
-
-// Message describes a message which has been posted to a Room.
-type Message struct {
-	ID        string `json:"id"`
-	UserID    UserID `json:"userID"`
-	Body      string `json:"body"`
-	CreatedAt int64  `json:"createdAt,omitempty"`
-}
-
-func msgFromStreamEntry(entry radix.StreamEntry) (Message, error) {
-
-	// NOTE this should probably be a shortcut in radix
-	var bodyStr string
-	for _, field := range entry.Fields {
-		if field[0] == "json" {
-			bodyStr = field[1]
-			break
-		}
-	}
-
-	if bodyStr == "" {
-		return Message{}, errors.New("no 'json' field")
-	}
-
-	var msg Message
-	if err := json.Unmarshal([]byte(bodyStr), &msg); err != nil {
-		return Message{}, fmt.Errorf(
-			"json unmarshaling body %q: %w", bodyStr, err,
-		)
-	}
-
-	msg.ID = entry.ID.String()
-	msg.CreatedAt = int64(entry.ID.Time / 1000)
-	return msg, nil
-}
-
-// MessageIterator returns a sequence of Messages which may or may not be
-// unbounded.
-type MessageIterator interface {
-
-	// Next blocks until it returns the next Message in the sequence, or the
-	// context error if the context is cancelled, or io.EOF if the sequence has
-	// been exhausted.
-	Next(context.Context) (Message, error)
-
-	// Close should always be called once Next has returned an error or the
-	// MessageIterator will no longer be used.
-	Close() error
-}
-
-// HistoryOpts are passed into Room's History method in order to affect its
-// result. All fields are optional.
-type HistoryOpts struct {
-	Limit  int    // defaults to, and is capped at, 100.
-	Cursor string // If not given then the most recent Messages are returned.
-}
-
-func (o HistoryOpts) sanitize() (HistoryOpts, error) {
-	if o.Limit <= 0 || o.Limit > 100 {
-		o.Limit = 100
-	}
-
-	if o.Cursor != "" {
-		id, err := parseStreamEntryID(o.Cursor)
-		if err != nil {
-			return HistoryOpts{}, fmt.Errorf("parsing Cursor: %w", err)
-		}
-		o.Cursor = id.String()
-	}
-
-	return o, nil
-}
-
-// Room implements functionality related to a single, unique chat room.
-type Room interface {
-
-	// Append accepts a new Message and stores it at the end of the room's
-	// history. The original Message is returned with any relevant fields (e.g.
-	// ID) updated.
-	Append(context.Context, Message) (Message, error)
-
-	// Returns a cursor and the list of historical Messages in time descending
-	// order. The cursor can be passed into the next call to History to receive
-	// the next set of Messages.
-	History(context.Context, HistoryOpts) (string, []Message, error)
-
-	// Listen returns a MessageIterator which will return all Messages appended
-	// to the Room since the given ID. Once all existing messages are iterated
-	// through then the MessageIterator will begin blocking until a new Message
-	// is posted.
-	Listen(ctx context.Context, sinceID string) (MessageIterator, error)
-
-	// Delete deletes a Message from the Room.
-	Delete(ctx context.Context, id string) error
-
-	// Close is used to clean up all resources created by the Room.
-	Close() error
-}
-
-// RoomParams are used to instantiate a new Room. All fields are required unless
-// otherwise noted.
-type RoomParams struct {
-	Logger      *mlog.Logger
-	Redis       radix.Client
-	ID          string
-	MaxMessages int
-}
-
-func (p RoomParams) streamKey() string {
-	return fmt.Sprintf("chat:{%s}:stream", p.ID)
-}
-
-type room struct {
-	params RoomParams
-
-	closeCtx    context.Context
-	closeCancel context.CancelFunc
-	wg          sync.WaitGroup
-
-	listeningL      sync.Mutex
-	listening       map[chan Message]struct{}
-	listeningLastID radix.StreamEntryID
-}
-
-// NewRoom initializes and returns a new Room instance.
-func NewRoom(ctx context.Context, params RoomParams) (Room, error) {
-
-	params.Logger = params.Logger.WithNamespace("chat-room")
-
-	r := &room{
-		params:    params,
-		listening: map[chan Message]struct{}{},
-	}
-
-	r.closeCtx, r.closeCancel = context.WithCancel(context.Background())
-
-	// figure out the most recent message, if any.
-	lastEntryID, err := r.mostRecentMsgID(ctx)
-	if err != nil {
-		return nil, fmt.Errorf("discovering most recent entry ID in stream: %w", err)
-	}
-	r.listeningLastID = lastEntryID
-
-	r.wg.Add(1)
-	go func() {
-		defer r.wg.Done()
-		r.readStreamLoop(r.closeCtx)
-	}()
-
-	return r, nil
-}
-
-func (r *room) Close() error {
-	r.closeCancel()
-	r.wg.Wait()
-	return nil
-}
-
-func (r *room) mostRecentMsgID(ctx context.Context) (radix.StreamEntryID, error) {
-
-	var entries []radix.StreamEntry
-	err := r.params.Redis.Do(ctx, radix.Cmd(
-		&entries,
-		"XREVRANGE", r.params.streamKey(), "+", "-", "COUNT", "1",
-	))
-
-	if err != nil || len(entries) == 0 {
-		return radix.StreamEntryID{}, err
-	}
-
-	return entries[0].ID, nil
-}
-
-func (r *room) Append(ctx context.Context, msg Message) (Message, error) {
-	msg.ID = "" // just in case
-
-	b, err := json.Marshal(msg)
-	if err != nil {
-		return Message{}, fmt.Errorf("json marshaling Message: %w", err)
-	}
-
-	key := r.params.streamKey()
-	maxLen := strconv.Itoa(r.params.MaxMessages)
-	body := string(b)
-
-	var id radix.StreamEntryID
-
-	err = r.params.Redis.Do(ctx, radix.Cmd(
-		&id, "XADD", key, "MAXLEN", "=", maxLen, "*", "json", body,
-	))
-
-	if err != nil {
-		return Message{}, fmt.Errorf("posting message to redis: %w", err)
-	}
-
-	msg.ID = id.String()
-	msg.CreatedAt = int64(id.Time / 1000)
-	return msg, nil
-}
-
-const zeroCursor = "0-0"
-
-func (r *room) History(ctx context.Context, opts HistoryOpts) (string, []Message, error) {
-	opts, err := opts.sanitize()
-	if err != nil {
-		return "", nil, err
-	}
-
-	key := r.params.streamKey()
-	end := opts.Cursor
-	if end == "" {
-		end = "+"
-	}
-	start := "-"
-	count := strconv.Itoa(opts.Limit)
-
-	msgs := make([]Message, 0, opts.Limit)
-	streamEntries := make([]radix.StreamEntry, 0, opts.Limit)
-
-	err = r.params.Redis.Do(ctx, radix.Cmd(
-		&streamEntries,
-		"XREVRANGE", key, end, start, "COUNT", count,
-	))
-
-	if err != nil {
-		return "", nil, fmt.Errorf("calling XREVRANGE: %w", err)
-	}
-
-	var oldestEntryID radix.StreamEntryID
-
-	for _, entry := range streamEntries {
-		oldestEntryID = entry.ID
-
-		msg, err := msgFromStreamEntry(entry)
-		if err != nil {
-			return "", nil, fmt.Errorf(
-				"parsing stream entry %q: %w", entry.ID, err,
-			)
-		}
-		msgs = append(msgs, msg)
-	}
-
-	if len(msgs) < opts.Limit {
-		return zeroCursor, msgs, nil
-	}
-
-	cursor := oldestEntryID.Prev()
-	return cursor.String(), msgs, nil
-}
-
-func (r *room) readStream(ctx context.Context) error {
-
-	r.listeningL.Lock()
-	lastEntryID := r.listeningLastID
-	r.listeningL.Unlock()
-
-	redisAddr := r.params.Redis.Addr()
-	redisConn, err := radix.Dial(ctx, redisAddr.Network(), redisAddr.String())
-	if err != nil {
-		return fmt.Errorf("creating redis connection: %w", err)
-	}
-	defer redisConn.Close()
-
-	streamReader := (radix.StreamReaderConfig{}).New(
-		redisConn,
-		map[string]radix.StreamConfig{
-			r.params.streamKey(): {After: lastEntryID},
-		},
-	)
-
-	for {
-		dlCtx, dlCtxCancel := context.WithTimeout(ctx, 10*time.Second)
-		_, streamEntry, err := streamReader.Next(dlCtx)
-		dlCtxCancel()
-
-		if errors.Is(err, radix.ErrNoStreamEntries) {
-			continue
-		} else if err != nil {
-			return fmt.Errorf("fetching next entry from stream: %w", err)
-		}
-
-		msg, err := msgFromStreamEntry(streamEntry)
-		if err != nil {
-			return fmt.Errorf("parsing stream entry %q: %w", streamEntry, err)
-		}
-
-		r.listeningL.Lock()
-
-		var dropped int
-		for ch := range r.listening {
-			select {
-			case ch <- msg:
-			default:
-				dropped++
-			}
-		}
-
-		if dropped > 0 {
-			ctx := mctx.Annotate(ctx, "msgID", msg.ID, "dropped", dropped)
-			r.params.Logger.WarnString(ctx, "some listening channels full, messages dropped")
-		}
-
-		r.listeningLastID = streamEntry.ID
-
-		r.listeningL.Unlock()
-	}
-}
-
-func (r *room) readStreamLoop(ctx context.Context) {
-	for {
-		err := r.readStream(ctx)
-		if errors.Is(err, context.Canceled) {
-			return
-		} else if err != nil {
-			r.params.Logger.Error(ctx, "reading from redis stream", err)
-		}
-	}
-}
-
-type listenMsgIterator struct {
-	ch           <-chan Message
-	missedMsgs   []Message
-	sinceEntryID radix.StreamEntryID
-	cleanup      func()
-}
-
-func (i *listenMsgIterator) Next(ctx context.Context) (Message, error) {
-
-	if len(i.missedMsgs) > 0 {
-		msg := i.missedMsgs[0]
-		i.missedMsgs = i.missedMsgs[1:]
-		return msg, nil
-	}
-
-	for {
-		select {
-		case <-ctx.Done():
-			return Message{}, ctx.Err()
-		case msg := <-i.ch:
-
-			entryID, err := parseStreamEntryID(msg.ID)
-			if err != nil {
-				return Message{}, fmt.Errorf("parsing Message ID %q: %w", msg.ID, err)
-
-			} else if !i.sinceEntryID.Before(entryID) {
-				// this can happen if someone Appends a Message at the same time
-				// as another calls Listen. The Listener might have already seen
-				// the Message by calling History prior to the stream reader
-				// having processed it and updating listeningLastID.
-				continue
-			}
-
-			return msg, nil
-		}
-	}
-}
-
-func (i *listenMsgIterator) Close() error {
-	i.cleanup()
-	return nil
-}
-
-func (r *room) Listen(
-	ctx context.Context, sinceID string,
-) (
-	MessageIterator, error,
-) {
-
-	var sinceEntryID radix.StreamEntryID
-
-	if sinceID != "" {
-		var err error
-		if sinceEntryID, err = parseStreamEntryID(sinceID); err != nil {
-			return nil, fmt.Errorf("parsing sinceID: %w", err)
-		}
-	}
-
-	ch := make(chan Message, 32)
-
-	r.listeningL.Lock()
-	lastEntryID := r.listeningLastID
-	r.listening[ch] = struct{}{}
-	r.listeningL.Unlock()
-
-	cleanup := func() {
-		r.listeningL.Lock()
-		defer r.listeningL.Unlock()
-		delete(r.listening, ch)
-	}
-
-	key := r.params.streamKey()
-	start := sinceEntryID.Next().String()
-	end := "+"
-	if lastEntryID != (radix.StreamEntryID{}) {
-		end = lastEntryID.String()
-	}
-
-	var streamEntries []radix.StreamEntry
-
-	err := r.params.Redis.Do(ctx, radix.Cmd(
-		&streamEntries,
-		"XRANGE", key, start, end,
-	))
-
-	if err != nil {
-		cleanup()
-		return nil, fmt.Errorf("retrieving missed stream entries: %w", err)
-	}
-
-	missedMsgs := make([]Message, len(streamEntries))
-
-	for i := range streamEntries {
-
-		msg, err := msgFromStreamEntry(streamEntries[i])
-		if err != nil {
-			cleanup()
-			return nil, fmt.Errorf(
-				"parsing stream entry %q: %w", streamEntries[i].ID, err,
-			)
-		}
-
-		missedMsgs[i] = msg
-	}
-
-	return &listenMsgIterator{
-		ch:           ch,
-		missedMsgs:   missedMsgs,
-		sinceEntryID: sinceEntryID,
-		cleanup:      cleanup,
-	}, nil
-}
-
-func (r *room) Delete(ctx context.Context, id string) error {
-	return r.params.Redis.Do(ctx, radix.Cmd(
-		nil, "XDEL", r.params.streamKey(), id,
-	))
-}
diff --git a/srv/src/chat/chat_it_test.go b/srv/src/chat/chat_it_test.go
deleted file mode 100644
index b0d4431..0000000
--- a/srv/src/chat/chat_it_test.go
+++ /dev/null
@@ -1,213 +0,0 @@
-//go:build integration
-// +build integration
-
-package chat
-
-import (
-	"context"
-	"strconv"
-	"testing"
-	"time"
-
-	"github.com/google/uuid"
-	cfgpkg "github.com/mediocregopher/blog.mediocregopher.com/srv/cfg"
-	"github.com/mediocregopher/mediocre-go-lib/v2/mlog"
-	"github.com/mediocregopher/radix/v4"
-	"github.com/stretchr/testify/assert"
-)
-
-const roomTestHarnessMaxMsgs = 10
-
-type roomTestHarness struct {
-	ctx     context.Context
-	room    Room
-	allMsgs []Message
-}
-
-func (h *roomTestHarness) newMsg(t *testing.T) Message {
-	msg, err := h.room.Append(h.ctx, Message{
-		UserID: UserID{
-			Name: uuid.New().String(),
-			Hash: "0000",
-		},
-		Body: uuid.New().String(),
-	})
-	assert.NoError(t, err)
-
-	t.Logf("appended message %s", msg.ID)
-
-	h.allMsgs = append([]Message{msg}, h.allMsgs...)
-
-	if len(h.allMsgs) > roomTestHarnessMaxMsgs {
-		h.allMsgs = h.allMsgs[:roomTestHarnessMaxMsgs]
-	}
-
-	return msg
-}
-
-func newRoomTestHarness(t *testing.T) *roomTestHarness {
-
-	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
-	t.Cleanup(cancel)
-
-	cfg := cfgpkg.NewBlogCfg(cfgpkg.Params{
-		Args: []string{}, // prevents the test process args from interfering
-	})
-
-	var radixClient cfgpkg.RadixClient
-	radixClient.SetupCfg(cfg)
-	t.Cleanup(func() { radixClient.Close() })
-
-	if err := cfg.Init(ctx); err != nil {
-		t.Fatal(err)
-	}
-
-	roomParams := RoomParams{
-		Logger:      mlog.NewLogger(nil),
-		Redis:       radixClient.Client,
-		ID:          uuid.New().String(),
-		MaxMessages: roomTestHarnessMaxMsgs,
-	}
-
-	t.Logf("creating test Room %q", roomParams.ID)
-	room, err := NewRoom(ctx, roomParams)
-	assert.NoError(t, err)
-
-	t.Cleanup(func() {
-		err := radixClient.Client.Do(context.Background(), radix.Cmd(
-			nil, "DEL", roomParams.streamKey(),
-		))
-		assert.NoError(t, err)
-	})
-
-	return &roomTestHarness{ctx: ctx, room: room}
-}
-
-func TestRoom(t *testing.T) {
-	t.Run("history", func(t *testing.T) {
-
-		tests := []struct {
-			numMsgs int
-			limit   int
-		}{
-			{numMsgs: 0, limit: 1},
-			{numMsgs: 1, limit: 1},
-			{numMsgs: 2, limit: 1},
-			{numMsgs: 2, limit: 10},
-			{numMsgs: 9, limit: 2},
-			{numMsgs: 9, limit: 3},
-			{numMsgs: 9, limit: 4},
-			{numMsgs: 15, limit: 3},
-		}
-
-		for i, test := range tests {
-			t.Run(strconv.Itoa(i), func(t *testing.T) {
-				t.Logf("test: %+v", test)
-
-				h := newRoomTestHarness(t)
-
-				for j := 0; j < test.numMsgs; j++ {
-					h.newMsg(t)
-				}
-
-				var gotMsgs []Message
-				var cursor string
-
-				for {
-
-					var msgs []Message
-					var err error
-					cursor, msgs, err = h.room.History(h.ctx, HistoryOpts{
-						Cursor: cursor,
-						Limit:  test.limit,
-					})
-
-					assert.NoError(t, err)
-					assert.NotEmpty(t, cursor)
-
-					if len(msgs) == 0 {
-						break
-					}
-
-					gotMsgs = append(gotMsgs, msgs...)
-				}
-
-				assert.Equal(t, h.allMsgs, gotMsgs)
-			})
-		}
-	})
-
-	assertNextMsg := func(
-		t *testing.T, expMsg Message,
-		ctx context.Context, it MessageIterator,
-	) {
-		t.Helper()
-		gotMsg, err := it.Next(ctx)
-		assert.NoError(t, err)
-		assert.Equal(t, expMsg, gotMsg)
-	}
-
-	t.Run("listen/already_populated", func(t *testing.T) {
-		h := newRoomTestHarness(t)
-
-		msgA, msgB, msgC := h.newMsg(t), h.newMsg(t), h.newMsg(t)
-		_ = msgA
-		_ = msgB
-
-		itFoo, err := h.room.Listen(h.ctx, msgC.ID)
-		assert.NoError(t, err)
-		defer itFoo.Close()
-
-		itBar, err := h.room.Listen(h.ctx, msgA.ID)
-		assert.NoError(t, err)
-		defer itBar.Close()
-
-		msgD := h.newMsg(t)
-
-		// itBar should get msgB and msgC before anything else.
-		assertNextMsg(t, msgB, h.ctx, itBar)
-		assertNextMsg(t, msgC, h.ctx, itBar)
-
-		// now both iterators should give msgD
-		assertNextMsg(t, msgD, h.ctx, itFoo)
-		assertNextMsg(t, msgD, h.ctx, itBar)
-
-		// timeout should be honored
-		{
-			timeoutCtx, timeoutCancel := context.WithTimeout(h.ctx, 1*time.Second)
-			_, errFoo := itFoo.Next(timeoutCtx)
-			_, errBar := itBar.Next(timeoutCtx)
-			timeoutCancel()
-
-			assert.ErrorIs(t, errFoo, context.DeadlineExceeded)
-			assert.ErrorIs(t, errBar, context.DeadlineExceeded)
-		}
-
-		// new message should work
-		{
-			expMsg := h.newMsg(t)
-
-			timeoutCtx, timeoutCancel := context.WithTimeout(h.ctx, 1*time.Second)
-			gotFooMsg, errFoo := itFoo.Next(timeoutCtx)
-			gotBarMsg, errBar := itBar.Next(timeoutCtx)
-			timeoutCancel()
-
-			assert.Equal(t, expMsg, gotFooMsg)
-			assert.NoError(t, errFoo)
-			assert.Equal(t, expMsg, gotBarMsg)
-			assert.NoError(t, errBar)
-		}
-
-	})
-
-	t.Run("listen/empty", func(t *testing.T) {
-		h := newRoomTestHarness(t)
-
-		it, err := h.room.Listen(h.ctx, "")
-		assert.NoError(t, err)
-		defer it.Close()
-
-		msg := h.newMsg(t)
-		assertNextMsg(t, msg, h.ctx, it)
-	})
-}
diff --git a/srv/src/chat/user.go b/srv/src/chat/user.go
deleted file mode 100644
index 3f5ab95..0000000
--- a/srv/src/chat/user.go
+++ /dev/null
@@ -1,68 +0,0 @@
-package chat
-
-import (
-	"encoding/hex"
-	"fmt"
-	"sync"
-
-	"golang.org/x/crypto/argon2"
-)
-
-// UserID uniquely identifies an individual user who has posted a message in a
-// Room.
-type UserID struct {
-
-	// Name will be the user's chosen display name.
-	Name string `json:"name"`
-
-	// Hash will be a hex string generated from a secret only the user knows.
-	Hash string `json:"id"`
-}
-
-// UserIDCalculator is used to calculate UserIDs.
-type UserIDCalculator struct {
-
-	// Secret is used when calculating UserID Hash salts.
-	Secret []byte
-
-	// TimeCost, MemoryCost, and Threads are used as inputs to the Argon2id
-	// algorithm which is used to generate the Hash.
-	TimeCost, MemoryCost uint32
-	Threads              uint8
-
-	// HashLen specifies the number of bytes the Hash should be.
-	HashLen uint32
-
-	// Lock, if set, forces concurrent Calculate calls to occur sequentially.
-	Lock *sync.Mutex
-}
-
-// NewUserIDCalculator returns a UserIDCalculator with sane defaults.
-func NewUserIDCalculator(secret []byte) *UserIDCalculator {
-	return &UserIDCalculator{
-		Secret:     secret,
-		TimeCost:   15,
-		MemoryCost: 128 * 1024,
-		Threads:    2,
-		HashLen:    16,
-		Lock:       new(sync.Mutex),
-	}
-}
-
-// Calculate accepts a name and password and returns the calculated UserID.
-func (c *UserIDCalculator) Calculate(name, password string) UserID {
-
-	input := fmt.Sprintf("%q:%q", name, password)
-
-	hashB := argon2.IDKey(
-		[]byte(input),
-		c.Secret, // salt
-		c.TimeCost, c.MemoryCost, c.Threads,
-		c.HashLen,
-	)
-
-	return UserID{
-		Name: name,
-		Hash: hex.EncodeToString(hashB),
-	}
-}
diff --git a/srv/src/chat/user_test.go b/srv/src/chat/user_test.go
deleted file mode 100644
index 2169cde..0000000
--- a/srv/src/chat/user_test.go
+++ /dev/null
@@ -1,26 +0,0 @@
-package chat
-
-import (
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-)
-
-func TestUserIDCalculator(t *testing.T) {
-
-	const name, password = "name", "password"
-
-	c := NewUserIDCalculator([]byte("foo"))
-
-	// calculating with same params twice should result in same UserID
-	userID := c.Calculate(name, password)
-	assert.Equal(t, userID, c.Calculate(name, password))
-
-	// changing either name or password should result in a different Hash
-	assert.NotEqual(t, userID.Hash, c.Calculate(name+"!", password).Hash)
-	assert.NotEqual(t, userID.Hash, c.Calculate(name, password+"!").Hash)
-
-	// changing the secret should change the UserID
-	c.Secret = []byte("bar")
-	assert.NotEqual(t, userID, c.Calculate(name, password))
-}
diff --git a/srv/src/chat/util.go b/srv/src/chat/util.go
deleted file mode 100644
index 05f4830..0000000
--- a/srv/src/chat/util.go
+++ /dev/null
@@ -1,28 +0,0 @@
-package chat
-
-import (
-	"strconv"
-	"strings"
-
-	"github.com/mediocregopher/radix/v4"
-)
-
-func parseStreamEntryID(str string) (radix.StreamEntryID, error) {
-
-	split := strings.SplitN(str, "-", 2)
-	if len(split) != 2 {
-		return radix.StreamEntryID{}, errInvalidMessageID
-	}
-
-	time, err := strconv.ParseUint(split[0], 10, 64)
-	if err != nil {
-		return radix.StreamEntryID{}, errInvalidMessageID
-	}
-
-	seq, err := strconv.ParseUint(split[1], 10, 64)
-	if err != nil {
-		return radix.StreamEntryID{}, errInvalidMessageID
-	}
-
-	return radix.StreamEntryID{Time: time, Seq: seq}, nil
-}
diff --git a/srv/src/cmd/mediocre-blog/main.go b/srv/src/cmd/mediocre-blog/main.go
index 694dd3f..4f8ba78 100644
--- a/srv/src/cmd/mediocre-blog/main.go
+++ b/srv/src/cmd/mediocre-blog/main.go
@@ -8,7 +8,6 @@ import (
 	"time"
 
 	cfgpkg "github.com/mediocregopher/blog.mediocregopher.com/srv/cfg"
-	"github.com/mediocregopher/blog.mediocregopher.com/srv/chat"
 	"github.com/mediocregopher/blog.mediocregopher.com/srv/http"
 	"github.com/mediocregopher/blog.mediocregopher.com/srv/mailinglist"
 	"github.com/mediocregopher/blog.mediocregopher.com/srv/post"
@@ -50,9 +49,6 @@ func main() {
 	defer radixClient.Close()
 	ctx = mctx.WithAnnotator(ctx, &radixClient)
 
-	chatGlobalRoomMaxMsgs := cfg.Int("chat-global-room-max-messages", 1000, "Maximum number of messages the global chat room can retain")
-	chatUserIDCalcSecret := cfg.String("chat-user-id-calc-secret", "", "Secret to use when calculating user ids")
-
 	// initialization
 	err := cfg.Init(ctx)
 
@@ -66,10 +62,6 @@ func main() {
 		logger.Fatal(ctx, "initializing", err)
 	}
 
-	ctx = mctx.Annotate(ctx,
-		"chatGlobalRoomMaxMsgs", *chatGlobalRoomMaxMsgs,
-	)
-
 	clock := clock.Realtime()
 
 	powStore := pow.NewMemoryStore(clock)
@@ -100,19 +92,6 @@ func main() {
 
 	ml := mailinglist.New(mlParams)
 
-	chatGlobalRoom, err := chat.NewRoom(ctx, chat.RoomParams{
-		Logger:      logger.WithNamespace("global-chat-room"),
-		Redis:       radixClient.Client,
-		ID:          "global",
-		MaxMessages: *chatGlobalRoomMaxMsgs,
-	})
-	if err != nil {
-		logger.Fatal(ctx, "initializing global chat room", err)
-	}
-	defer chatGlobalRoom.Close()
-
-	chatUserIDCalc := chat.NewUserIDCalculator([]byte(*chatUserIDCalcSecret))
-
 	postSQLDB, err := post.NewSQLDB(dataDir)
 	if err != nil {
 		logger.Fatal(ctx, "initializing sql db for post data", err)
@@ -129,8 +108,6 @@ func main() {
 	httpParams.PostAssetStore = postAssetStore
 	httpParams.PostDraftStore = postDraftStore
 	httpParams.MailingList = ml
-	httpParams.GlobalRoom = chatGlobalRoom
-	httpParams.UserIDCalculator = chatUserIDCalc
 
 	logger.Info(ctx, "listening")
 	httpAPI, err := http.New(httpParams)
diff --git a/srv/src/cmd/userid-calc-cli/main.go b/srv/src/cmd/userid-calc-cli/main.go
deleted file mode 100644
index 90c44e7..0000000
--- a/srv/src/cmd/userid-calc-cli/main.go
+++ /dev/null
@@ -1,28 +0,0 @@
-package main
-
-import (
-	"encoding/json"
-	"flag"
-	"fmt"
-
-	"github.com/mediocregopher/blog.mediocregopher.com/srv/chat"
-)
-
-func main() {
-
-	secret := flag.String("secret", "", "Secret to use when calculating UserIDs")
-	name := flag.String("name", "", "")
-	password := flag.String("password", "", "")
-
-	flag.Parse()
-
-	calc := chat.NewUserIDCalculator([]byte(*secret))
-	userID := calc.Calculate(*name, *password)
-
-	b, err := json.Marshal(userID)
-	if err != nil {
-		panic(err)
-	}
-
-	fmt.Println(string(b))
-}
diff --git a/srv/src/http/api.go b/srv/src/http/api.go
index 44b9170..01cad50 100644
--- a/srv/src/http/api.go
+++ b/srv/src/http/api.go
@@ -17,7 +17,6 @@ import (
 
 	lru "github.com/hashicorp/golang-lru"
 	"github.com/mediocregopher/blog.mediocregopher.com/srv/cfg"
-	"github.com/mediocregopher/blog.mediocregopher.com/srv/chat"
 	"github.com/mediocregopher/blog.mediocregopher.com/srv/http/apiutil"
 	"github.com/mediocregopher/blog.mediocregopher.com/srv/mailinglist"
 	"github.com/mediocregopher/blog.mediocregopher.com/srv/post"
@@ -41,9 +40,6 @@ type Params struct {
 
 	MailingList mailinglist.MailingList
 
-	GlobalRoom       chat.Room
-	UserIDCalculator *chat.UserIDCalculator
-
 	// PublicURL is the base URL which site visitors can navigate to.
 	PublicURL *url.URL
 
@@ -176,16 +172,9 @@ func (a *api) apiHandler() http.Handler {
 	mux.Handle("/mailinglist/finalize", a.mailingListFinalizeHandler())
 	mux.Handle("/mailinglist/unsubscribe", a.mailingListUnsubscribeHandler())
 
-	mux.Handle("/chat/global/", http.StripPrefix("/chat/global", newChatHandler(
-		a.params.GlobalRoom,
-		a.params.UserIDCalculator,
-		a.requirePowMiddleware,
-	)))
-
-	// disallowGetMiddleware is used rather than a MethodMux because it has an
-	// exception for websockets, which is needed for chat.
-	return disallowGetMiddleware(mux)
-
+	return apiutil.MethodMux(map[string]http.Handler{
+		"POST": mux,
+	})
 }
 
 func (a *api) blogHandler() http.Handler {
diff --git a/srv/src/http/chat.go b/srv/src/http/chat.go
deleted file mode 100644
index f76e4ad..0000000
--- a/srv/src/http/chat.go
+++ /dev/null
@@ -1,211 +0,0 @@
-package http
-
-import (
-	"context"
-	"errors"
-	"fmt"
-	"net/http"
-	"strings"
-	"unicode"
-
-	"github.com/gorilla/websocket"
-	"github.com/mediocregopher/blog.mediocregopher.com/srv/chat"
-	"github.com/mediocregopher/blog.mediocregopher.com/srv/http/apiutil"
-)
-
-type chatHandler struct {
-	*http.ServeMux
-
-	room       chat.Room
-	userIDCalc *chat.UserIDCalculator
-
-	wsUpgrader websocket.Upgrader
-}
-
-func newChatHandler(
-	room chat.Room, userIDCalc *chat.UserIDCalculator,
-	requirePowMiddleware func(http.Handler) http.Handler,
-) http.Handler {
-	c := &chatHandler{
-		ServeMux:   http.NewServeMux(),
-		room:       room,
-		userIDCalc: userIDCalc,
-
-		wsUpgrader: websocket.Upgrader{},
-	}
-
-	c.Handle("/history", c.historyHandler())
-	c.Handle("/user-id", requirePowMiddleware(c.userIDHandler()))
-	c.Handle("/append", requirePowMiddleware(c.appendHandler()))
-	c.Handle("/listen", c.listenHandler())
-
-	return c
-}
-
-func (c *chatHandler) historyHandler() http.Handler {
-	return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
-		limit, err := apiutil.StrToInt(r.PostFormValue("limit"), 0)
-		if err != nil {
-			apiutil.BadRequest(rw, r, fmt.Errorf("invalid limit parameter: %w", err))
-			return
-		}
-
-		cursor := r.PostFormValue("cursor")
-
-		cursor, msgs, err := c.room.History(r.Context(), chat.HistoryOpts{
-			Limit:  limit,
-			Cursor: cursor,
-		})
-
-		if argErr := (chat.ErrInvalidArg{}); errors.As(err, &argErr) {
-			apiutil.BadRequest(rw, r, argErr.Err)
-			return
-		} else if err != nil {
-			apiutil.InternalServerError(rw, r, err)
-		}
-
-		apiutil.JSONResult(rw, r, struct {
-			Cursor   string         `json:"cursor"`
-			Messages []chat.Message `json:"messages"`
-		}{
-			Cursor:   cursor,
-			Messages: msgs,
-		})
-	})
-}
-
-func (c *chatHandler) userID(r *http.Request) (chat.UserID, error) {
-	name := r.PostFormValue("name")
-	if l := len(name); l == 0 {
-		return chat.UserID{}, errors.New("name is required")
-	} else if l > 16 {
-		return chat.UserID{}, errors.New("name too long")
-	}
-
-	nameClean := strings.Map(func(r rune) rune {
-		if !unicode.IsPrint(r) {
-			return -1
-		}
-		return r
-	}, name)
-
-	if nameClean != name {
-		return chat.UserID{}, errors.New("name contains invalid characters")
-	}
-
-	password := r.PostFormValue("password")
-	if l := len(password); l == 0 {
-		return chat.UserID{}, errors.New("password is required")
-	} else if l > 128 {
-		return chat.UserID{}, errors.New("password too long")
-	}
-
-	return c.userIDCalc.Calculate(name, password), nil
-}
-
-func (c *chatHandler) userIDHandler() http.Handler {
-	return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
-		userID, err := c.userID(r)
-		if err != nil {
-			apiutil.BadRequest(rw, r, err)
-			return
-		}
-
-		apiutil.JSONResult(rw, r, struct {
-			UserID chat.UserID `json:"userID"`
-		}{
-			UserID: userID,
-		})
-	})
-}
-
-func (c *chatHandler) appendHandler() http.Handler {
-	return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
-		userID, err := c.userID(r)
-		if err != nil {
-			apiutil.BadRequest(rw, r, err)
-			return
-		}
-
-		body := r.PostFormValue("body")
-
-		if l := len(body); l == 0 {
-			apiutil.BadRequest(rw, r, errors.New("body is required"))
-			return
-
-		} else if l > 300 {
-			apiutil.BadRequest(rw, r, errors.New("body too long"))
-			return
-		}
-
-		msg, err := c.room.Append(r.Context(), chat.Message{
-			UserID: userID,
-			Body:   body,
-		})
-
-		if err != nil {
-			apiutil.InternalServerError(rw, r, err)
-			return
-		}
-
-		apiutil.JSONResult(rw, r, struct {
-			MessageID string `json:"messageID"`
-		}{
-			MessageID: msg.ID,
-		})
-	})
-}
-
-func (c *chatHandler) listenHandler() http.Handler {
-	return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
-
-		ctx := r.Context()
-		sinceID := r.FormValue("sinceID")
-
-		conn, err := c.wsUpgrader.Upgrade(rw, r, nil)
-		if err != nil {
-			apiutil.BadRequest(rw, r, err)
-			return
-		}
-		defer conn.Close()
-
-		it, err := c.room.Listen(ctx, sinceID)
-
-		if errors.As(err, new(chat.ErrInvalidArg)) {
-			apiutil.BadRequest(rw, r, err)
-			return
-
-		} else if errors.Is(err, context.Canceled) {
-			return
-
-		} else if err != nil {
-			apiutil.InternalServerError(rw, r, err)
-			return
-		}
-
-		defer it.Close()
-
-		for {
-
-			msg, err := it.Next(ctx)
-			if errors.Is(err, context.Canceled) {
-				return
-
-			} else if err != nil {
-				apiutil.InternalServerError(rw, r, err)
-				return
-			}
-
-			err = conn.WriteJSON(struct {
-				Message chat.Message `json:"message"`
-			}{
-				Message: msg,
-			})
-
-			if err != nil {
-				apiutil.GetRequestLogger(r).Error(ctx, "couldn't write message", err)
-				return
-			}
-		}
-	})
-}
diff --git a/srv/src/http/tpl/chat.html b/srv/src/http/tpl/chat.html
deleted file mode 100644
index b2038e2..0000000
--- a/srv/src/http/tpl/chat.html
+++ /dev/null
@@ -1,251 +0,0 @@
-{{ define "body" }}
-
-<script async type="module" src="/assets/api.js"></script>
-
-<style>
-    #messages {
-        max-height: 65vh;
-        overflow: auto;
-        padding-right: 2rem;
-    }
-
-    #messages .message {
-        border: 1px solid #AAA;
-        border-radius: 10px;
-        margin-bottom: 1rem;
-        padding: 2rem;
-        overflow: auto;
-    }
-
-    #messages .message .title {
-        font-weight: bold;
-        font-size: 120%;
-    }
-
-    #messages .message .secondaryTitle {
-        font-family: monospace;
-        color: #CCC;
-    }
-
-    #messages .message p {
-        font-family: monospace;
-        margin: 1rem 0 0 0;
-    }
-
-</style>
-
-<div id="messages"></div>
-
-<span id="fail" style="color: red;"></span>
-
-<script>
-
-const messagesEl = document.getElementById("messages");
-
-let messagesScrolledToBottom = true;
-messagesEl.onscroll = () => {
-    const el = messagesEl;
-    messagesScrolledToBottom = el.scrollHeight == el.scrollTop + el.clientHeight;
-};
-
-function renderMessages(msgs) {
-
-    messagesEl.innerHTML = '';
-
-    msgs.forEach((msg) => {
-        const el = document.createElement("div");
-        el.className = "row message"
-
-        const elWithTextContents = (tag, body) => {
-            const el = document.createElement(tag);
-            el.appendChild(document.createTextNode(body));
-            return el;
-        };
-
-        const titleEl = document.createElement("div");
-        titleEl.className = "title";
-        el.appendChild(titleEl);
-
-        const userNameEl = elWithTextContents("span", msg.userID.name);
-        titleEl.appendChild(userNameEl);
-
-        const secondaryTitleEl = document.createElement("div");
-        secondaryTitleEl.className = "secondaryTitle";
-        el.appendChild(secondaryTitleEl);
-
-        const dt = new Date(msg.createdAt*1000);
-        const dtStr
-            = `${dt.getFullYear()}-${dt.getMonth()+1}-${dt.getDate()}`
-            + ` ${dt.getHours()}:${dt.getMinutes()}:${dt.getSeconds()}`;
-
-        const userIDEl = elWithTextContents("span", `userID:${msg.userID.id} @ ${dtStr}`);
-        secondaryTitleEl.appendChild(userIDEl);
-
-        const bodyEl = document.createElement("p");
-
-        const bodyParts = msg.body.split("\n");
-        for (const i in bodyParts) {
-            if (i > 0) bodyEl.appendChild(document.createElement("br"));
-            bodyEl.appendChild(document.createTextNode(bodyParts[i]));
-        }
-
-        el.appendChild(bodyEl);
-
-        messagesEl.appendChild(el);
-    });
-}
-
-
-(async () => {
-
-    const failEl = document.getElementById("fail");
-    setErr = (msg) => failEl.innerHTML = `${msg} (please refresh the page to retry)`;
-
-    try {
-
-        const api = await import("/assets/api.js");
-
-        const history = await api.call("/api/chat/global/history");
-        const msgs = history.messages;
-
-        // history returns msgs in time descending, but we display them in time
-        // ascending.
-        msgs.reverse()
-
-        const sinceID = (msgs.length > 0) ?  msgs[msgs.length-1].id : "";
-
-        const ws = await api.ws("/api/chat/global/listen", {
-            params: { sinceID },
-        });
-
-        while (true) {
-            renderMessages(msgs);
-
-            // If the user was previously scrolled to the bottom then keep them
-            // there.
-            if (messagesScrolledToBottom) {
-                messagesEl.scrollTop = messagesEl.scrollHeight;
-            }
-
-            const msg = await ws.next();
-            msgs.push(msg.message);
-            renderMessages(msgs);
-        }
-
-
-    } catch (e) {
-        e = `Failed to fetch message history: ${e}`
-        setErr(e);
-        console.error(e);
-        return;
-    }
-
-})()
-
-</script>
-
-<style>
-#append {
-    border: 1px dashed #AAA;
-    border-radius: 10px;
-    padding: 2rem;
-}
-
-#append #appendBody {
-    font-family: monospace;
-}
-
-#append #appendStatus {
-    color: red;
-}
-
-</style>
-
-<form id="append">
-    <h5>New Message</h5>
-    <div class="row">
-        <div class="columns four">
-            <input class="u-full-width" placeholder="Name" id="appendName" type="text" />
-            <input class="u-full-width" placeholder="Secret" id="appendSecret" type="password" />
-        </div>
-        <div class="columns eight">
-            <p>
-                Your name is displayed alongside your message.
-
-                Your name+secret is used to generate your userID, which is also
-                displayed alongside your message.
-
-                Other users can validate two messages are from the same person
-                by comparing the messages' userID.
-            </p>
-        </div>
-    </div>
-    <div class="row">
-        <div class="columns twelve">
-            <textarea
-                style="font-family: monospace"
-                id="appendBody"
-                class="u-full-width"
-                placeholder="Well thought out statement goes here..."
-                ></textarea>
-        </div>
-    </div>
-    <div class="row">
-        <div class="columns four">
-            <input class="u-full-width button-primary" id="appendSubmit" type="button" value="Submit" />
-        </div>
-    </div>
-    <span id="appendStatus"></span>
-</form>
-
-<script>
-
-const append = document.getElementById("append");
-const appendName = document.getElementById("appendName");
-const appendSecret = document.getElementById("appendSecret");
-const appendBody = document.getElementById("appendBody");
-const appendSubmit = document.getElementById("appendSubmit");
-const appendStatus = document.getElementById("appendStatus");
-
-appendSubmit.onclick = async () => {
-
-    const appendSubmitOrigValue = appendSubmit.value;
-
-    appendSubmit.disabled = true;
-    appendSubmit.className = "";
-    appendSubmit.value = "Please hold...";
-
-    appendStatus.innerHTML = '';
-
-    try {
-
-        const api = await import("/assets/api.js");
-
-        await api.call('/api/chat/global/append', {
-            body: {
-                name: appendName.value,
-                password: appendSecret.value,
-                body: appendBody.value,
-            },
-            requiresPow: true,
-        });
-
-        appendBody.value = '';
-
-    } catch (e) {
-
-        appendStatus.innerHTML = e;
-
-    } finally {
-        appendSubmit.disabled = false;
-        appendSubmit.className = "button-primary";
-        appendSubmit.value = appendSubmitOrigValue;
-    }
-};
-
-</script>
-
-{{ end }}
-
-{{ template "base.html" . }}
-