package slacknotifier import ( "bytes" "context" "fmt" "time" "golang.org/x/time/rate" "github.com/c9s/bbgo/pkg/types" log "github.com/sirupsen/logrus" "github.com/slack-go/slack" ) var limiter = rate.NewLimiter(rate.Every(1*time.Second), 1) type notifyTask struct { Channel string Opts []slack.MsgOption } type slackAttachmentCreator interface { SlackAttachment() slack.Attachment } type Notifier struct { client *slack.Client channel string taskC chan notifyTask } type NotifyOption func(notifier *Notifier) func New(client *slack.Client, channel string, options ...NotifyOption) *Notifier { notifier := &Notifier{ channel: channel, client: client, taskC: make(chan notifyTask, 100), } for _, o := range options { o(notifier) } go notifier.worker() return notifier } func (n *Notifier) worker() { ctx := context.Background() for { select { case <-ctx.Done(): return case task := <-n.taskC: limiter.Wait(ctx) _, _, err := n.client.PostMessageContext(ctx, task.Channel, task.Opts...) if err != nil { log.WithError(err). WithField("channel", task.Channel). Errorf("slack api error: %s", err.Error()) } } } } func (n *Notifier) Notify(obj interface{}, args ...interface{}) { n.NotifyTo(n.channel, obj, args...) } func filterSlackAttachments(args []interface{}) (slackAttachments []slack.Attachment, pureArgs []interface{}) { var firstAttachmentOffset = -1 for idx, arg := range args { switch a := arg.(type) { // concrete type assert first case slack.Attachment: if firstAttachmentOffset == -1 { firstAttachmentOffset = idx } slackAttachments = append(slackAttachments, a) case slackAttachmentCreator: if firstAttachmentOffset == -1 { firstAttachmentOffset = idx } slackAttachments = append(slackAttachments, a.SlackAttachment()) case types.PlainText: if firstAttachmentOffset == -1 { firstAttachmentOffset = idx } // fallback to PlainText if it's not supported // convert plain text to slack attachment text := a.PlainText() slackAttachments = append(slackAttachments, slack.Attachment{ Title: text, }) } } pureArgs = args if firstAttachmentOffset > -1 { pureArgs = args[:firstAttachmentOffset] } return slackAttachments, pureArgs } func (n *Notifier) NotifyTo(channel string, obj interface{}, args ...interface{}) { if len(channel) == 0 { channel = n.channel } slackAttachments, pureArgs := filterSlackAttachments(args) var opts []slack.MsgOption switch a := obj.(type) { case string: opts = append(opts, slack.MsgOptionText(fmt.Sprintf(a, pureArgs...), true), slack.MsgOptionAttachments(slackAttachments...)) case slack.Attachment: opts = append(opts, slack.MsgOptionAttachments(append([]slack.Attachment{a}, slackAttachments...)...)) case slackAttachmentCreator: // convert object to slack attachment (if supported) opts = append(opts, slack.MsgOptionAttachments(append([]slack.Attachment{a.SlackAttachment()}, slackAttachments...)...)) default: log.Errorf("slack message conversion error, unsupported object: %T %+v", a, a) } select { case n.taskC <- notifyTask{ Channel: channel, Opts: opts, }: case <-time.After(50 * time.Millisecond): return } } func (n *Notifier) SendPhoto(buffer *bytes.Buffer) { n.SendPhotoTo(n.channel, buffer) } func (n *Notifier) SendPhotoTo(channel string, buffer *bytes.Buffer) { // TODO } /* func (n *Notifier) NotifyTrade(trade *types.Trade) { _, _, err := n.client.PostMessageContext(context.Background(), n.TradeChannel, slack.MsgOptionText(util.Render(`:handshake: {{ .Symbol }} {{ .Side }} Trade Execution @ {{ .Price }}`, trade), true), slack.MsgOptionAttachments(trade.SlackAttachment())) if err != nil { logrus.WithError(err).Error("slack send error") } } */ /* func (n *Notifier) NotifyPnL(report *pnl.AverageCostPnlReport) { attachment := report.SlackAttachment() _, _, err := n.client.PostMessageContext(context.Background(), n.PnlChannel, slack.MsgOptionText(util.Render( `:heavy_dollar_sign: Here is your *{{ .symbol }}* PnL report collected since *{{ .startTime }}*`, map[string]interface{}{ "symbol": report.Symbol, "startTime": report.StartTime.Format(time.RFC822), }), true), slack.MsgOptionAttachments(attachment)) if err != nil { logrus.WithError(err).Errorf("slack send error") } } */