webhook_poller.go

package main

import (
	"context"
	"encoding/json"
	"fmt"
	"log"
	"net/http"

	"gopkg.in/tucnak/telebot.v2"
)

type WebhookPoller struct {
	updatesChan chan telebot.Update
}

func (p *WebhookPoller) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	var update telebot.Update
	err := json.NewDecoder(r.Body).Decode(&update)
	if err != nil {
		return
	}
	p.updatesChan <- update
}

func (h *WebhookPoller) Poll(
	b *telebot.Bot,
	dest chan telebot.Update,
	stop chan struct{},
) {
	whUrl := fmt.Sprintf(
		"https://%s:%s/%s",
		getEnvPanic("WEBHOOK_DOMAIN"),
		getEnvPanic("WEBHOOK_PORT"),
		getEnvPanic("WEBHOOK_SECRET_PATH"),
	)
	h.updatesChan = dest

	webhookResult, err := b.Raw("setWebhook", map[string]string{
		"url":                  whUrl,
		"drop_pending_updates": "true",
	})
	log.Printf("Set webhook: %s", string(webhookResult))
	if err != nil {
		close(stop)
		log.Fatal(err)
	}

	s := &http.Server{
		Addr:    ":" + getEnvPanic("SERVER_PORT"),
		Handler: h,
	}

	go func(stop chan struct{}, s *http.Server) {
		<-stop
		close(stop)
		s.Shutdown(context.Background())
	}(stop, s)

	s.ListenAndServe()
}