Fix few bugs with notification and chatid migrations

Author: Vladimir Smirnov

endpoints/telegram/telegram_endpoint.go

@@ -2,21 +2,23 @@ package telegram
 
 import (
 	"fmt"
-	"github.com/Civil/github2telegram/configs"
-	"github.com/Civil/github2telegram/db"
-	"github.com/Civil/github2telegram/endpoints"
-	"github.com/Civil/github2telegram/feeds"
-	"github.com/Civil/github2telegram/types"
-	"github.com/lomik/zapwriter"
-	"github.com/mymmrac/telego"
-	tu "github.com/mymmrac/telego/telegoutil"
-	"github.com/pkg/errors"
-	"go.uber.org/zap"
 	"net/http"
 	"regexp"
 	"strconv"
 	"strings"
 	"time"
+
+	"github.com/lomik/zapwriter"
+	"github.com/mymmrac/telego"
+	tu "github.com/mymmrac/telego/telegoutil"
+	"github.com/pkg/errors"
+	"go.uber.org/zap"
+
+	"github.com/Civil/github2telegram/configs"
+	"github.com/Civil/github2telegram/db"
+	"github.com/Civil/github2telegram/endpoints"
+	"github.com/Civil/github2telegram/feeds"
+	"github.com/Civil/github2telegram/types"
 )
 
 const (
@@ -287,7 +289,7 @@ func (e *TelegramEndpoint) Send(url, filter, message string) error {
 
 func (e *TelegramEndpoint) checkAndChangeChatID(logger *zap.Logger, id int64, error string) int64 {
 	if strings.Contains(error, "migrate to chat ID:") {
-		re := regexp.MustCompile(`migrate\s+to\s+chat\s+ID:\s([-0-9]+).`)
+		re := regexp.MustCompile(`migrate\s+to\s+chat\s+ID:\s([-0-9]+)`)
 		matches := re.FindStringSubmatch(error)
 		if len(matches) != 2 {
 			logger.Error("failed to parse new chat id, either no matches or too many matches found",
@@ -305,6 +307,14 @@ func (e *TelegramEndpoint) checkAndChangeChatID(logger *zap.Logger, id int64, er
 			)
 			return id
 		}
+		if newID == 0 {
+			logger.Error("failed to parse new chat id",
+				zap.String("newIDStr", newIDStr),
+				zap.String("original_error", error),
+				zap.Any("matches", matches),
+			)
+			return id
+		}
 		err = e.db.UpdateChatID(id, newID)
 		if err != nil {
 			logger.Error("failed to update chat id",
@@ -546,6 +556,11 @@ func (e *TelegramEndpoint) handlerSubscribe(tokens []string, update *telego.Upda
 	}
 
 	chatID := update.Message.Chat.ID
+	if chatID == 0 {
+		logger.Error("chat id is 0, that shouldn't happen", zap.Any("update", update))
+		_ = e.sendMessage(update.Message.Chat.ID, update.Message.MessageID, "failed to subscribe as bot cannot determine chat_id, please try again later")
+		return errors.New("cannot detect chat_id, subscription failed")
+	}
 	err := e.db.AddSubscribtion(TelegramEndpointName, url, filterName, chatID)
 	if err != nil {
 		if errors.Is(err, db.ErrAlreadyExists) {

feeds/process.go

@@ -1,16 +1,17 @@
 package feeds
 
 import (
-	"github.com/Civil/github2telegram/types"
+	"math/rand"
 	"regexp"
+	"strings"
 	"time"
 
-	"github.com/Civil/github2telegram/configs"
-	"github.com/Civil/github2telegram/db"
+	"github.com/Civil/github2telegram/types"
+
 	"github.com/pkg/errors"
 
-	"math/rand"
-	"strings"
+	"github.com/Civil/github2telegram/configs"
+	"github.com/Civil/github2telegram/db"
 
 	"github.com/lomik/zapwriter"
 	"github.com/lunny/html2md"
@@ -193,17 +194,17 @@ func (f *Feed) processSingleItem(cfg *configs.FeedsConfig, url string, item *gof
 			logger.Debug("filter matched")
 			contentTruncated := false
 			var changeType UpdateType
-			var notification string
 
 			// check if last tag haven't changed
 			if item.Title == cfg.Filters[i].LastTag {
 				changeType = DescriptionChange
-				notification = types.MdReplacer.Replace(cfg.Repo) + " description changed: " + item.Title + "\nLink: " + types.MdReplacer.Replace(item.Link)
+
 			} else {
 				changeType = NewRelease
-				notification = types.MdReplacer.Replace(cfg.Repo) + " tagged: " + types.MdReplacer.Replace(item.Title) + "\nLink: " + types.MdReplacer.Replace(item.Link)
 			}
 
+			notification := types.MdReplacer.Replace(cfg.Repo) + changeType.String() + types.MdReplacer.Replace(item.Title) + "\nLink: " + types.MdReplacer.Replace(item.Link)
+
 			content := html2md.Convert(item.Content)
 			if len(content) > 250 {
 				content = content[:250] + "\\.\\.\\."

feeds/types.go

@@ -8,6 +8,19 @@ const (
 	DescriptionChange
 )
 
+func (t UpdateType) String() string {
+	switch t {
+	case NewRelease:
+		return " tagged: "
+	case Retag:
+		return " re-tagged: "
+	case DescriptionChange:
+		return " description changed: "
+	default:
+		return " (unhandled update type): "
+	}
+}
+
 type Update struct {
 	Type   UpdateType
 	Repo   string