all: add livenote and livenoteposter, move all example strategy into pkg/strategy/example

Author: c9s

README.md

@@ -392,10 +392,10 @@ persistence:
 
 Check out the strategy directory [strategy](pkg/strategy) for all built-in strategies:
 
-- `pricealert` strategy demonstrates how to use the notification system [pricealert](pkg/strategy/pricealert). See
+- `pricealert` strategy demonstrates how to use the notification system [pricealert](pkg/strategy/example/pricealert). See
   [document](./doc/strategy/pricealert.md).
 - `buyandhold` strategy demonstrates how to subscribe kline events and submit market
-  order [buyandhold](pkg/strategy/pricedrop)
+  order [buyandhold](pkg/strategy/example/pricedrop)
 - `bollgrid` strategy implements a basic grid strategy with the built-in bollinger
   indicator [bollgrid](pkg/strategy/bollgrid)
 - `grid` strategy implements the fixed price band grid strategy [grid](pkg/strategy/grid). See

README.zh_TW.md

@@ -370,8 +370,8 @@ persistence:
 
 查看策略目錄 [strategy](pkg/strategy) 以獲得所有內置策略：
 
-- `pricealert` 策略演示如何使用通知系統 [pricealert](pkg/strategy/pricealert)。參見[文件](./doc/strategy/pricealert.md).
-- `buyandhold` 策略演示如何訂閱 kline 事件並提交市場訂單 [buyandhold](pkg/strategy/pricedrop)
+- `pricealert` 策略演示如何使用通知系統 [pricealert](pkg/strategy/example/pricealert)。參見[文件](./doc/strategy/pricealert.md).
+- `buyandhold` 策略演示如何訂閱 kline 事件並提交市場訂單 [buyandhold](pkg/strategy/example/pricedrop)
 - `bollgrid` 策略實現了一個基本的網格策略，使用內置的布林通道指標 [bollgrid](pkg/strategy/bollgrid)
 - `grid` 策略實現了固定價格帶網格策略 [grid](pkg/strategy/grid)。參見[文件](./doc/strategy/grid.md).
 - `supertrend` 策略使用 Supertrend 指標作為趨勢，並使用 DEMA 指標作為噪聲
@@ -621,4 +621,4 @@ make embed && go run -tags web ./cmd/bbgo-lorca
 
 ## 授權
 
-AGPL 授權
+AGPL 授權

pkg/bbgo/livenote.go

@@ -0,0 +1,21 @@
+package bbgo
+
+import (
+	"github.com/sirupsen/logrus"
+
+	"github.com/c9s/bbgo/pkg/types"
+)
+
+// PostLiveNote posts a live note to slack or other services
+// The MessageID will be set after the message is posted if it's not set.
+func PostLiveNote(note *types.LiveNote) {
+	for _, poster := range Notification.liveNotePosters {
+		if err := poster.PostLiveNote(note); err != nil {
+			logrus.WithError(err).Errorf("unable to post live note: %+v", note)
+		}
+	}
+}
+
+type LiveNotePoster interface {
+	PostLiveNote(note *types.LiveNote) error
+}

pkg/bbgo/notification.go

@@ -48,7 +48,9 @@ func (n *NullNotifier) SendPhoto(buffer *bytes.Buffer) {}
 func (n *NullNotifier) SendPhotoTo(channel string, buffer *bytes.Buffer) {}
 
 type Notifiability struct {
-	notifiers            []Notifier
+	notifiers       []Notifier
+	liveNotePosters []LiveNotePoster
+
 	SessionChannelRouter *PatternChannelRouter `json:"-"`
 	SymbolChannelRouter  *PatternChannelRouter `json:"-"`
 	ObjectChannelRouter  *ObjectChannelRouter  `json:"-"`
@@ -81,6 +83,10 @@ func (m *Notifiability) RouteObject(obj interface{}) (channel string, ok bool) {
 // AddNotifier adds the notifier that implements the Notifier interface.
 func (m *Notifiability) AddNotifier(notifier Notifier) {
 	m.notifiers = append(m.notifiers, notifier)
+
+	if poster, ok := notifier.(LiveNotePoster); ok {
+		m.liveNotePosters = append(m.liveNotePosters, poster)
+	}
 }
 
 func (m *Notifiability) Notify(obj interface{}, args ...interface{}) {

pkg/notifier/slacknotifier/slack.go

@@ -54,7 +54,8 @@ func (n *Notifier) worker() {
 			return
 
 		case task := <-n.taskC:
-			limiter.Wait(ctx)
+			// ignore the wait error
+			_ = limiter.Wait(ctx)
 
 			_, _, err := n.client.PostMessageContext(ctx, task.Channel, task.Opts...)
 			if err != nil {
@@ -66,7 +67,40 @@ func (n *Notifier) worker() {
 	}
 }
 
+func (n *Notifier) PostLiveNote(note *types.LiveNote) error {
+	ctx := context.Background()
+
+	channel := note.ChannelID
+	if channel == "" {
+		channel = n.channel
+	}
+
+	if note.MessageID != "" {
+		// UpdateMessageContext returns channel, timestamp, text, err
+		_, _, _, err := n.client.UpdateMessageContext(ctx, channel, note.MessageID, slack.MsgOptionText(note.ObjectID(), true))
+		if err != nil {
+			return err
+		}
+
+	} else {
+
+		respCh, respTs, err := n.client.PostMessageContext(ctx, channel)
+		if err != nil {
+			log.WithError(err).
+				WithField("channel", n.channel).
+				Errorf("slack api error: %s", err.Error())
+			return err
+		}
+
+		note.SetChannelID(respCh)
+		note.SetMessageID(respTs)
+	}
+
+	return nil
+}
+
 func (n *Notifier) Notify(obj interface{}, args ...interface{}) {
+	// TODO: filter args for the channel option
 	n.NotifyTo(n.channel, obj, args...)
 }
 

pkg/strategy/pricealert/strategy.go pkg/strategy/example/pricealert/strategy.go

@@ -0,0 +1,33 @@
+package types
+
+type LiveNoteObject interface {
+	ObjectID() string
+}
+
+type LiveNote struct {
+	// MessageID is the unique identifier of the message
+	// for slack, it's the timestamp of the message
+	MessageID string `json:"messageId"`
+
+	ChannelID string `json:"channelId"`
+
+	Object LiveNoteObject
+}
+
+func NewLiveNote(object LiveNoteObject) *LiveNote {
+	return &LiveNote{
+		Object: object,
+	}
+}
+
+func (n *LiveNote) ObjectID() string {
+	return n.Object.ObjectID()
+}
+
+func (n *LiveNote) SetMessageID(messageID string) {
+	n.MessageID = messageID
+}
+
+func (n *LiveNote) SetChannelID(channelID string) {
+	n.ChannelID = channelID
+}