feat: long poller error backoff

v1/context/context.go

@@ -2,7 +2,7 @@ package context
 
 import (
 	"context"
-	"github.com/abelith/gomax/v1/state"
+	"github.com/abelith/gomax/v1/fsm/state"
 	maxbot "github.com/max-messenger/max-bot-api-client-go/v2"
 	"github.com/max-messenger/max-bot-api-client-go/v2/model"
 	"time"

v1/core/dispatcher.go

@@ -4,13 +4,14 @@ import (
 	"context"
 	"errors"
 	mcontext "github.com/abelith/gomax/v1/context"
+	"github.com/abelith/gomax/v1/core/pollers"
+	"github.com/abelith/gomax/v1/fsm/memory"
+	"github.com/abelith/gomax/v1/fsm/state"
 	"github.com/abelith/gomax/v1/isolation"
-	"github.com/abelith/gomax/v1/state"
-	"github.com/abelith/gomax/v1/state/memory"
 	"github.com/google/uuid"
 	maxbot "github.com/max-messenger/max-bot-api-client-go/v2"
 	"github.com/max-messenger/max-bot-api-client-go/v2/model"
-	"github.com/rs/zerolog/log"
+	"github.com/rs/zerolog"
 	"sync"
 	"time"
 )
@@ -27,9 +28,9 @@ type EventIsolation interface {
 }
 
 type FSMStorage interface {
-	Get(ctx context.Context, userID int) (state.Snapshot, error)
+	Get(ctx context.Context, scope isolation.Scope) (state.Snapshot, error)
 	Put(ctx context.Context, state state.Snapshot) error
-	Delete(ctx context.Context, userID int) error
+	Delete(ctx context.Context, scope isolation.Scope) error
 }
 
 type UpdateHandler interface {
@@ -39,6 +40,7 @@ type UpdateHandler interface {
 
 type Poller interface {
 	Start(ctx context.Context) (<-chan model.Update, error)
+	Stop(ctx context.Context) error
 }
 
 type DispatcherOption interface {
@@ -50,7 +52,10 @@ type Dispatcher struct {
 	poller         Poller
 	fsmStorage     FSMStorage
 	eventIsolation EventIsolation
+	onStart        func(ctx context.Context) error
+	onStop         func(ctx context.Context) error
 	rt             *Router
+	logger         zerolog.Logger
 	wg             sync.WaitGroup
 }
 
@@ -58,6 +63,7 @@ type dispatcherOptions struct {
 	poller         Poller
 	fsmStorage     FSMStorage
 	eventIsolation EventIsolation
+	logger         zerolog.Logger
 }
 
 type dispatcherOptionWrapper struct {
@@ -78,6 +84,7 @@ func NewDispatcher(api *maxbot.Api, options ...DispatcherOption) *Dispatcher {
 	d.poller = opts.poller
 	d.fsmStorage = opts.fsmStorage
 	d.eventIsolation = opts.eventIsolation
+	d.logger = opts.logger
 
 	return d
 }
@@ -104,11 +111,49 @@ func (d *Dispatcher) Start(ctx context.Context) error {
 		return err
 	}
 
+	if d.onStart != nil {
+		if err := d.onStart(ctx); err != nil {
+			return err
+		}
+	}
+
 	d.handleUpdates(ch)
-	d.wg.Wait()
 	return nil
 }
 
+func (d *Dispatcher) Stop(ctx context.Context) error {
+	if err := d.poller.Stop(ctx); err != nil {
+		return err
+	}
+
+	done := make(chan struct{})
+
+	go func() {
+		d.wg.Wait()
+		done <- struct{}{}
+	}()
+
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-done:
+	}
+
+	if d.onStop != nil {
+		return d.onStop(ctx)
+	}
+
+	return nil
+}
+
+func (d *Dispatcher) OnStart(f func(ctx context.Context) error) {
+	d.onStart = f
+}
+
+func (d *Dispatcher) OnStop(f func(ctx context.Context) error) {
+	d.onStop = f
+}
+
 func (d *Dispatcher) handleUpdates(ch <-chan model.Update) {
 	for upd := range ch {
 		d.wg.Go(func() {
@@ -117,7 +162,7 @@ func (d *Dispatcher) handleUpdates(ch <-chan model.Update) {
 				UserID:   upd.UserID,
 				ChatID:   upd.ChatID,
 			}
-			l := log.With().
+			l := d.logger.With().
 				Str("update_id", key.UpdateID.String()).
 				Int64("user_id", key.UserID).
 				Int64("chat_id", key.ChatID).
@@ -127,7 +172,7 @@ func (d *Dispatcher) handleUpdates(ch <-chan model.Update) {
 			defer cancel()
 
 			if err := d.eventIsolation.Lock(lockCtx, key); err != nil {
-				log.Error().
+				d.logger.Error().
 					Err(err).
 					Int64("user_id", key.UserID).
 					Int64("chat_id", key.ChatID).
@@ -157,13 +202,13 @@ func (d *Dispatcher) handleUpdates(ch <-chan model.Update) {
 func (d *Dispatcher) handleUpdate(ctx context.Context, upd model.Update) {
 	var st *state.Context
 
-	snapshot, err := d.fsmStorage.Get(ctx, int(upd.UserID))
+	snapshot, err := d.fsmStorage.Get(ctx, isolation.Scope{UserID: upd.UserID, ChatID: upd.ChatID})
 	if err != nil && !errors.Is(err, state.ErrStateNotFound) {
-		log.Error().Err(err).Send()
+		d.logger.Error().Err(err).Send()
 		return
 	}
 	if errors.Is(err, state.ErrStateNotFound) {
-		st = state.New(int(upd.UserID))
+		st = state.New(isolation.Scope{UserID: upd.UserID, ChatID: upd.ChatID})
 	} else {
 		st = state.Restore(snapshot)
 	}
@@ -171,22 +216,20 @@ func (d *Dispatcher) handleUpdate(ctx context.Context, upd model.Update) {
 	c := mcontext.New(ctx, upd, st, d.api)
 
 	if err := d.rt.HandleUpdate(c); err != nil {
-		log.Error().Err(err).Send()
+		d.logger.Error().Err(err).Send()
 		return
 	}
 
 	st = c.State()
-	if st.State() == state.ClearState {
-		if err := d.fsmStorage.Delete(ctx, int(upd.UserID)); err != nil {
-			log.Error().Err(err).Send()
-			return
+	if st.IsEmpty() {
+		if err := d.fsmStorage.Delete(ctx, isolation.Scope{UserID: upd.UserID, ChatID: upd.ChatID}); err != nil {
+			d.logger.Error().Err(err).Send()
 		}
+		return
 	}
-	if st.State() != "" {
-		if err := d.fsmStorage.Put(ctx, st.Snapshot()); err != nil {
-			log.Error().Err(err).Send()
-			return
-		}
+
+	if err := d.fsmStorage.Put(ctx, st.Snapshot()); err != nil {
+		d.logger.Error().Err(err).Send()
 	}
 }
 
@@ -208,11 +251,18 @@ func WithEventIsolation(eventIsolation EventIsolation) DispatcherOption {
 	})
 }
 
+func WithZerolog(logger zerolog.Logger) DispatcherOption {
+	return newOption(func(options *dispatcherOptions) {
+		options.logger = logger
+	})
+}
+
 func newDispatcherOptions(api *maxbot.Api) *dispatcherOptions {
 	return &dispatcherOptions{
-		poller:         NewLongPoller(api),
+		poller:         pollers.NewLongPoller(api),
 		fsmStorage:     memory.NewFSMStorage(),
 		eventIsolation: memory.NewEventIsolation(defaultTTL),
+		logger:         zerolog.Nop(),
 	}
 }
 

v1/core/pollers/pollers.go

@@ -1,4 +1,4 @@
-package core
+package pollers
 
 import (
 	"context"
@@ -6,6 +6,7 @@ import (
 	"errors"
 	maxbot "github.com/max-messenger/max-bot-api-client-go/v2"
 	"github.com/max-messenger/max-bot-api-client-go/v2/model"
+	"github.com/rs/zerolog"
 	"github.com/rs/zerolog/log"
 	"net"
 	"net/http"
@@ -29,11 +30,14 @@ type LongPollerOption interface {
 type Webhook struct {
 	srv *http.Server
 	ch  chan model.Update
+	wg  *sync.WaitGroup
 }
 
 type LongPoller struct {
 	api          *maxbot.Api
 	pollInterval time.Duration
+	logger       zerolog.Logger
+	wg           sync.WaitGroup
 }
 
 type TestPoller struct {
@@ -41,6 +45,19 @@ type TestPoller struct {
 	mu sync.Mutex
 }
 
+type backoff struct {
+	base time.Duration
+	max  time.Duration
+
+	window []bool
+	pos    int
+	count  int
+	errors int
+
+	sinceAdjust int
+	interval    time.Duration
+}
+
 type webhookOptions struct {
 	addr              string
 	tlsConfig         *tls.Config
@@ -55,6 +72,11 @@ type webhookOptions struct {
 
 type longPollerOptions struct {
 	pollInterval time.Duration
+	logger       zerolog.Logger
+}
+
+type longPollerOptionWrapper struct {
+	fn func(opts *longPollerOptions)
 }
 
 type webhookOptionWrapper struct {
@@ -98,38 +120,36 @@ func NewWebhookPoller(api *maxbot.Api, secret string, options ...WebhookOption)
 	return wh
 }
 
-func (w *Webhook) Start(_ context.Context) (<-chan model.Update, error) {
-	errCh := make(chan error, 1)
-	defer close(errCh)
+func (w *Webhook) Start(ctx context.Context) (<-chan model.Update, error) {
+	l, err := net.Listen("tcp", w.srv.Addr)
+	if err != nil {
+		return nil, err
+	}
 
 	go func() {
 		var err error
-		defer func() {
-			errCh <- err
-			if err != nil && !errors.Is(err, http.ErrServerClosed) {
-				log.Fatal().Err(err).Msg("webhook server error")
-			}
-		}()
 
 		if w.srv.TLSConfig == nil {
-			err = w.srv.ListenAndServe()
-			return
+			err = w.srv.Serve(l)
+		} else {
+			err = w.srv.ServeTLS(l, "", "")
 		}
 
-		err = w.srv.ListenAndServeTLS("", "")
+		if err != nil && !errors.Is(err, http.ErrServerClosed) {
+			log.Ctx(ctx).Error().Err(err).Msg("failed to start webhook server")
+		}
 	}()
 
-	select {
-	case err := <-errCh:
-		return nil, err
-	case <-time.After(defaultWhStartTimeout):
-		return w.ch, nil
-	}
+	return w.ch, nil
 }
 
 func (w *Webhook) Stop(ctx context.Context) error {
-	close(w.ch)
-	return w.srv.Shutdown(ctx)
+	defer close(w.ch)
+
+	if err := w.srv.Shutdown(ctx); err != nil {
+		return err
+	}
+	return nil
 }
 
 func NewLongPoller(api *maxbot.Api, options ...LongPollerOption) *LongPoller {
@@ -143,50 +163,38 @@ func NewLongPoller(api *maxbot.Api, options ...LongPollerOption) *LongPoller {
 	}
 
 	lp.pollInterval = opts.pollInterval
+	lp.logger = opts.logger
 
 	return lp
 }
 
 func (lp *LongPoller) Start(ctx context.Context) (<-chan model.Update, error) {
-	var updates []model.Update
-	var marker int64
-	var err error
-
 	ch := make(chan model.Update)
 
-	go func() {
+	lp.wg.Go(func() {
 		defer close(ch)
-
-		// todo: backoff on errors
-
-		for {
-			select {
-			case <-ctx.Done():
-				return
-			case <-time.Tick(lp.pollInterval):
-				start := time.Now()
-				updates, marker, err = lp.api.Subscriptions.GetUpdates(ctx, marker)
-				latency := time.Since(start)
-				if err != nil && !errors.Is(err, context.Canceled) {
-					log.Error().Err(err).Send()
-				}
-				log.Ctx(ctx).Debug().
-					Int("received", len(updates)).
-					Dur("latency", latency).
-					Msg("received updates")
-
-				for _, update := range updates {
-					select {
-					case ch <- update:
-					}
-				}
-			}
-		}
-	}()
+		lp.poll(ctx, ch)
+	})
 
 	return ch, nil
 }
 
+func (lp *LongPoller) Stop(ctx context.Context) error {
+	done := make(chan struct{})
+
+	go func() {
+		lp.wg.Wait()
+		done <- struct{}{}
+	}()
+
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-done:
+		return nil
+	}
+}
+
 func (tp *TestPoller) Inject(ctx context.Context, updates []model.Update) {
 	ch := make(chan model.Update, 1)
 
@@ -210,6 +218,22 @@ func (tp *TestPoller) Start(_ context.Context) (<-chan model.Update, error) {
 	return tp.ch, nil
 }
 
+func (tp *TestPoller) Stop(_ context.Context) error {
+	return nil
+}
+
+func WithPollInterval(interval time.Duration) LongPollerOption {
+	return newLpOption(func(opts *longPollerOptions) {
+		opts.pollInterval = interval
+	})
+}
+
+func WithZerolog(logger zerolog.Logger) LongPollerOption {
+	return newLpOption(func(opts *longPollerOptions) {
+		opts.logger = logger
+	})
+}
+
 func WithAddress(addr string) WebhookOption {
 	return newWhOption(func(opts *webhookOptions) {
 		opts.addr = addr
@@ -264,9 +288,112 @@ func WithConnContext(fn func(ctx context.Context, c net.Conn) context.Context) W
 	})
 }
 
+func newBackoff(
+	base, max time.Duration,
+	windowSize int,
+) *backoff {
+	if base <= 0 || max < base || windowSize <= 0 {
+		panic("backoff: invalid configuration")
+	}
+
+	return &backoff{
+		base:     base,
+		max:      max,
+		window:   make([]bool, windowSize),
+		interval: base,
+	}
+}
+
+func (b *backoff) observe(err error) time.Duration {
+	failed := err != nil
+
+	if b.count == len(b.window) && b.window[b.pos] {
+		b.errors--
+	} else {
+		b.count++
+	}
+
+	b.window[b.pos] = failed
+	if failed {
+		b.errors++
+	}
+
+	b.pos = (b.pos + 1) % len(b.window)
+	b.sinceAdjust++
+
+	if b.count < len(b.window) ||
+		b.sinceAdjust < len(b.window) {
+		return b.interval
+	}
+
+	b.sinceAdjust = 0
+	errorRate := float64(b.errors) / float64(b.count)
+
+	switch {
+	case errorRate >= 0.3:
+		b.interval = min(b.interval*2, b.max)
+	case errorRate <= 0.1:
+		b.interval = max(b.interval/2, b.base)
+	}
+
+	return b.interval
+}
+
+func (lp *LongPoller) poll(ctx context.Context, ch chan model.Update) {
+	b := newBackoff(
+		lp.pollInterval,
+		30*time.Second,
+		20,
+	)
+
+	var marker int64
+
+	for {
+		if err := wait(ctx, b.interval); err != nil {
+			return
+		}
+
+		start := time.Now()
+		updates, nextMarker, err := lp.api.Subscriptions.GetUpdates(ctx, marker)
+		latency := time.Since(start)
+
+		if err != nil {
+			if errors.Is(err, context.Canceled) ||
+				ctx.Err() != nil {
+				return
+			}
+
+			delay := b.observe(err)
+
+			lp.logger.Error().
+				Err(err).
+				Dur("latency", latency).
+				Dur("next_interval", delay).
+				Msg("failed to receive updates")
+
+			continue
+		}
+
+		b.observe(nil)
+		marker = nextMarker
+
+		lp.logger.Debug().
+			Int("received", len(updates)).
+			Dur("latency", latency).
+			Msg("received updates")
+
+		for _, update := range updates {
+			select {
+			case ch <- update:
+			}
+		}
+	}
+}
+
 func newLongPollerOptions() *longPollerOptions {
 	return &longPollerOptions{
 		pollInterval: defaultInterval,
+		logger:       zerolog.Nop(),
 	}
 }
 
@@ -276,10 +403,30 @@ func newWebhookOptions() *webhookOptions {
 	}
 }
 
+func newLpOption(fn func(opts *longPollerOptions)) LongPollerOption {
+	return longPollerOptionWrapper{fn: fn}
+}
+
 func newWhOption(fn func(options *webhookOptions)) WebhookOption {
 	return webhookOptionWrapper{fn: fn}
 }
 
+func (low longPollerOptionWrapper) apply(opts *longPollerOptions) {
+	low.fn(opts)
+}
+
 func (wow webhookOptionWrapper) apply(opts *webhookOptions) {
 	wow.fn(opts)
 }
+
+func wait(ctx context.Context, delay time.Duration) error {
+	timer := time.NewTimer(delay)
+	defer timer.Stop()
+
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-timer.C:
+		return nil
+	}
+}

v1/filters/filters.go

@@ -2,7 +2,7 @@ package filters
 
 import (
 	mcontext "github.com/abelith/gomax/v1/context"
-	"github.com/abelith/gomax/v1/state"
+	"github.com/abelith/gomax/v1/fsm/state"
 	"github.com/max-messenger/max-bot-api-client-go/v2/model"
 	"regexp"
 	"strings"

v1/fsm/memory/memory.go

@@ -2,8 +2,8 @@ package memory
 
 import (
 	"context"
+	"github.com/abelith/gomax/v1/fsm/state"
 	"github.com/abelith/gomax/v1/isolation"
-	"github.com/abelith/gomax/v1/state"
 	"github.com/google/uuid"
 	"sync"
 	"time"
@@ -19,6 +19,11 @@ type EventIsolation struct {
 	ttl   time.Duration
 }
 
+type fsmKey struct {
+	userID int64
+	chatID int64
+}
+
 type eventIsolationKey struct {
 	userID int
 	chatID int
@@ -34,8 +39,11 @@ func NewFSMStorage() *FSMStorage {
 	return &FSMStorage{}
 }
 
-func (f *FSMStorage) Get(_ context.Context, userID int) (state.Snapshot, error) {
-	st, ok := f.m.Load(userID)
+func (f *FSMStorage) Get(_ context.Context, scope isolation.Scope) (state.Snapshot, error) {
+	st, ok := f.m.Load(fsmKey{
+		userID: scope.UserID,
+		chatID: scope.ChatID,
+	})
 	if !ok {
 		return state.Snapshot{}, state.ErrStateNotFound
 	}
@@ -44,12 +52,18 @@ func (f *FSMStorage) Get(_ context.Context, userID int) (state.Snapshot, error)
 }
 
 func (f *FSMStorage) Put(_ context.Context, snapshot state.Snapshot) error {
-	f.m.Store(snapshot.ID, snapshot)
+	f.m.Store(fsmKey{
+		userID: snapshot.Scope.UserID,
+		chatID: snapshot.Scope.ChatID,
+	}, snapshot)
 	return nil
 }
 
-func (f *FSMStorage) Delete(_ context.Context, userID int) error {
-	f.m.Delete(userID)
+func (f *FSMStorage) Delete(_ context.Context, scope isolation.Scope) error {
+	f.m.Delete(fsmKey{
+		userID: scope.UserID,
+		chatID: scope.ChatID,
+	})
 	return nil
 }
 

v1/fsm/state/state.go

@@ -3,8 +3,8 @@ package state
 import (
 	"encoding/json"
 	"fmt"
-
-	"github.com/rs/zerolog/log"
+	"github.com/abelith/gomax/v1/isolation"
+	"strings"
 )
 
 var (
@@ -12,9 +12,15 @@ var (
 	ErrKeyNotFound   = fmt.Errorf("state: key not found")
 )
 
-const ClearState State = "clear"
+type State struct {
+	group string
+	name  string
+}
 
-type State string
+type Group struct {
+	name   string
+	states map[string]*State
+}
 
 type Codec interface {
 	Marshal(v any) ([]byte, error)
@@ -32,25 +38,69 @@ func (JSONCodec) Unmarshal(d []byte, v any) error {
 }
 
 type Snapshot struct {
-	ID    int               `json:"id"`
-	State State             `json:"state"`
+	Scope isolation.Scope   `json:"id"`
+	State string            `json:"state"`
 	Data  map[string][]byte `json:"data"`
 }
 
 type Context struct {
-	id    int
+	scope isolation.Scope
 	state State
 	data  map[string][]byte
 	codec Codec
+	clear bool
 }
 
 type Option func(*Context)
 
+func NewStateGroup(name string) *Group {
+	return &Group{
+		name:   name,
+		states: make(map[string]*State),
+	}
+}
+
+func (g *Group) State(name string) State {
+	state := g.states[name]
+
+	if state != nil {
+		return *state
+	}
+
+	if state = g.states[name]; state != nil {
+		return *state
+	}
+
+	state = &State{
+		group: g.name,
+		name:  name,
+	}
+
+	g.states[name] = state
+	return *state
+}
+
+func (s *State) String() string {
+	return fmt.Sprintf("%s:%s", s.group, s.name)
+}
+
+func fromString(s string) State {
+	pieces := strings.Split(s, ":")
+	if len(pieces) < 2 {
+		return State{}
+	}
+
+	return State{
+		group: pieces[0],
+		name:  pieces[1],
+	}
+}
+
 func WithCodec(c Codec) Option { return func(sc *Context) { sc.codec = c } }
 
-func New(id int, opts ...Option) *Context {
+func New(scope isolation.Scope, opts ...Option) *Context {
 	sc := &Context{
-		id:    id,
+		scope: scope,
 		data:  make(map[string][]byte),
 		codec: JSONCodec{},
 	}
@@ -61,8 +111,8 @@ func New(id int, opts ...Option) *Context {
 }
 
 func Restore(s Snapshot, opts ...Option) *Context {
-	sc := New(s.ID, opts...)
-	sc.state = s.State
+	sc := New(s.Scope, opts...)
+	sc.state = fromString(s.State)
 	for k, v := range s.Data {
 		sc.data[k] = v
 	}
@@ -74,25 +124,25 @@ func (sc *Context) Snapshot() Snapshot {
 	for k, v := range sc.data {
 		data[k] = v
 	}
-	return Snapshot{ID: sc.id, State: sc.state, Data: data}
+	return Snapshot{Scope: sc.scope, State: sc.state.String(), Data: data}
 }
 
 func (sc *Context) Set(state State) {
-	log.Debug().
-		Int("user_id", sc.id).
-		Str("from", string(sc.state)).
-		Str("to", string(state)).
-		Msg("fsm state transition")
 	sc.state = state
 }
 
 func (sc *Context) State() State { return sc.state }
 
 func (sc *Context) Clear() {
-	sc.state = ClearState
+	sc.state = State{}
+	sc.clear = true
 	sc.data = make(map[string][]byte)
 }
 
+func (sc *Context) IsEmpty() bool {
+	return sc.state == State{} && sc.clear
+}
+
 func (sc *Context) Store(key string, val any) error {
 	b, err := sc.codec.Marshal(val)
 	if err != nil {

v1/middleware/middleware.go

@@ -2,20 +2,20 @@ package middleware
 
 import (
 	"errors"
+	"fmt"
 	mcontext "github.com/abelith/gomax/v1/context"
 	"github.com/abelith/gomax/v1/core"
 	merrors "github.com/abelith/gomax/v1/errors"
-	"github.com/rs/zerolog"
-	"github.com/rs/zerolog/log"
 )
 
-func MwPanicHandler() core.Middleware {
+func MwPanicHandler(onPanic func()) core.Middleware {
 	return func(next core.HandlerFunc) core.HandlerFunc {
-		return func(c *mcontext.Context) error {
+		return func(c *mcontext.Context) (err error) {
 			defer func() {
 				p := recover()
 				if p != nil {
-					log.Fatal().Any("panic", p).Send()
+					onPanic()
+					err = fmt.Errorf("panic: %v", p)
 				}
 			}()
 			return next(c)
@@ -30,45 +30,34 @@ func MwErrorResponder(defaultMsg string) core.Middleware {
 			var maxErr *merrors.GoMaxError
 
 			if errors.As(err, &maxErr) {
-				return c.Respond(maxErr.Message)
+				return errors.Join(c.Respond(maxErr.Message), maxErr)
 			}
 
 			if err != nil {
-				return c.Respond(defaultMsg)
+				return errors.Join(c.Respond(defaultMsg), err)
 			}
 			return nil
 		}
 	}
 }
 
-func MwLoggerInjector(logger zerolog.Logger) core.Middleware {
+func MwCallback(callback func(c *mcontext.Context)) core.Middleware {
 	return func(next core.HandlerFunc) core.HandlerFunc {
 		return func(c *mcontext.Context) error {
-			ctx := logger.With().Int64("user_id", c.Update().UserID).
-				Logger().WithContext(c.Context())
-			c.SetContext(ctx)
+			callback(c)
 			return next(c)
 		}
 	}
 }
 
-func MwDebugState() core.Middleware {
+func MwErrorHandler(onError func(err error)) core.Middleware {
 	return func(next core.HandlerFunc) core.HandlerFunc {
 		return func(c *mcontext.Context) error {
-			log.Debug().Any("state", c.State()).Any("update", c.Update()).Send()
-			return next(c)
-		}
-	}
-}
-
-func MwErrorLogger() core.Middleware {
-	return func(next core.HandlerFunc) core.HandlerFunc {
-		return func(c *mcontext.Context) error {
-			if err := next(c); err != nil {
-				log.Ctx(c).Err(err).Send()
-				return err
+			var err error
+			if err = next(c); err != nil {
+				onError(err)
 			}
-			return nil
+			return err
 		}
 	}
 }