fix: handle deleted messages

docker-compose.yaml

@@ -7,7 +7,9 @@ services:
     env_file:
       - .env
     environment:
-      MYSQL_DB_DSN: discordgit:password@tcp(db:3306)/discordgit?charset=utf8mb4&parseTime=True&loc=UTC
+      LOG_LEVEL: DEBUG
+      UPDATE_TASK_CRON: "* * * * *"
+      MYSQL_DB_DSN: discordgit:password@tcp(db:3306)/discordgit?charset=utf8mb4&parseTime=True&loc=UTC\
     ports:
       - 2112:2112
     depends_on:

internal/manager/messages.go

@@ -64,7 +64,7 @@ func CreateNewLinkedMessage(log *logrus.Entry, s DiscordSessionInterface, dbConn
 		MessageID:    msgIDs[0],
 		MessageChain: msgIDs,
 		LinkedPage:   datatypes.URL(*contentURL),
-		NextUpdate: time.Now().Add(updateRateSetting.DurationValue),
+		NextUpdate:   time.Now().Add(updateRateSetting.DurationValue),
 	}).Error
 	if err != nil {
 		log.WithError(err).Error("cloud not save message data in db")
@@ -102,7 +102,7 @@ func UpdateMessage(log *logrus.Entry, s DiscordSessionInterface, dbConn *gorm.DB
 		log.WithError(err).Error("could not build embed objects")
 		return err
 	}
-
+	
 	msgIds := make([]string, len(embeds))
 	for i, e := range embeds {
 		var msg *discordgo.Message
@@ -113,6 +113,13 @@ func UpdateMessage(log *logrus.Entry, s DiscordSessionInterface, dbConn *gorm.DB
 		}
 
 		if err != nil {
+			if restErr, ok := err.(*discordgo.RESTError); ok {
+				err = handleRESTErrors(log, s, dbConn, &linkedMessage, restErr)
+				if err == nil {
+					return nil
+				}
+			}
+
 			log.WithError(err).Error("could not update message chain")
 			return err
 		}
@@ -150,6 +157,21 @@ func UpdateMessage(log *logrus.Entry, s DiscordSessionInterface, dbConn *gorm.DB
 	return nil
 }
 
+func handleRESTErrors(log *logrus.Entry, s DiscordSessionInterface, dbConn *gorm.DB, linkedMessage *db.LinkedMessage, err *discordgo.RESTError) error {
+	log.Debug("handling rest error")
+	switch err.Message.Code {
+	case discordgo.ErrCodeUnknownMessage:
+		log.Debug("deleting stale message")
+		return dbConn.Delete(linkedMessage).Error
+	case discordgo.ErrCodePerformedOperationOnArchivedThread: 
+		// TODO(roadmap) Figure out what to do about archived threads
+	default:
+		log.WithError(err).Warn("unknown rest error")
+		return err
+	}
+	return nil
+}
+
 // Fetch content of url as string
 func fetchPage(log *logrus.Entry, link *url.URL) (string, error) {
 	res, err := http.Get(link.String())
@@ -168,7 +190,7 @@ func fetchPage(log *logrus.Entry, link *url.URL) (string, error) {
 	return string(body), nil
 }
 
-var pageBreakFinder = regexp.MustCompile(`(?m)^-{3,}$`) // TODO Remove need for regex
+var pageBreakFinder = regexp.MustCompile(`(?m)^-{3,}$`) // TODO(maint) Remove need for regex
 
 // Break raw page content into embed blocks to send or update
 func buildEmbedContents(content string, link *url.URL, pageBreakSetting bool) ([]*discordgo.MessageEmbed, error) {

internal/scheduler/scheduler.go

@@ -1,11 +1,16 @@
 package scheduler
 
 import (
+	"fmt"
 	"time"
 
 	"github.com/go-co-op/gocron/v2"
+	"github.com/google/uuid"
 	"github.com/graytonio/discord-git-sync/internal/db"
 	"github.com/graytonio/discord-git-sync/internal/manager"
+	"github.com/graytonio/discord-git-sync/internal/metrics"
+	"github.com/graytonio/discord-git-sync/internal/utils"
+	"github.com/prometheus/client_golang/prometheus"
 	"github.com/sirupsen/logrus"
 	"gorm.io/gorm"
 )
@@ -16,7 +21,7 @@ import (
 
 func InitJobScheduler(db *gorm.DB, s manager.DiscordSessionInterface) (gocron.Scheduler, error) {
 	var err error
-	// locker, err := gormlock.NewGormLocker(db, os.Getenv("WORKER_ID")) // TODO Update dependency after bump
+	// locker, err := gormlock.NewGormLocker(db, os.Getenv("WORKER_ID")) // TODO(roadmap) Update dependency after bump
 	// if err != nil {
 	//   return err
 	// }
@@ -27,8 +32,10 @@ func InitJobScheduler(db *gorm.DB, s manager.DiscordSessionInterface) (gocron.Sc
 	}
 
 	scheduler.NewJob(
-		gocron.CronJob("*/5 * * * *", false), // TODO Configurable
+		gocron.CronJob(utils.GetEnv("UPDATE_TASK_CRON", "*/5 * * * *"), false),
 		gocron.NewTask(fetchAndDispatchMessageUpdates, db, scheduler, s),
+		gocron.WithName("message-batch-collection"),
+		gocron.WithSingletonMode(gocron.LimitModeReschedule),
 	)
 
 	scheduler.Start()
@@ -52,10 +59,18 @@ func fetchAndDispatchMessageUpdates(dbConn *gorm.DB, scheduler gocron.Scheduler,
 		})
 
 		log.Debug("auto updating linked message")
-
 		scheduler.NewJob(
 			gocron.OneTimeJob(gocron.OneTimeJobStartImmediately()),
 			gocron.NewTask(manager.UpdateMessage, log, s, dbConn, m.GuildID, m.ChannelID, m.MessageID),
+			gocron.WithName(fmt.Sprintf("message-update-%s", m.MessageID)),
+			gocron.WithEventListeners(
+				gocron.AfterJobRuns(func(jobID uuid.UUID, jobName string) {
+					metrics.CommandsServed.With(prometheus.Labels{"command": "auto-update"}).Inc()
+				}),
+				gocron.AfterJobRunsWithError(func(jobID uuid.UUID, jobName string, err error) {
+					metrics.CommandsFailed.With(prometheus.Labels{"command": "auto-update"}).Inc()
+				}),
+			),
 		)
 	}
 }

internal/utils/utils.go

@@ -0,0 +1,10 @@
+package utils
+
+import "os"
+
+func GetEnv(key, fallback string) string {
+    if value, ok := os.LookupEnv(key); ok {
+        return value
+    }
+    return fallback
+}

main.go

@@ -9,17 +9,23 @@ import (
 	"github.com/graytonio/discord-git-sync/internal/db"
 	"github.com/graytonio/discord-git-sync/internal/metrics"
 	"github.com/graytonio/discord-git-sync/internal/scheduler"
+	"github.com/graytonio/discord-git-sync/internal/utils"
 	"github.com/sirupsen/logrus"
 )
 
 func main() {
+	logLevel, err := logrus.ParseLevel(utils.GetEnv("LOG_LEVEL", "INFO"))
+	if err != nil {
+	  logrus.WithField("LOG_LEVEL", utils.GetEnv("LOG_LEVEL", "INFO")).Warn("invalid log level defaulting to info")
+	  logLevel = logrus.InfoLevel
+	}
+	logrus.SetLevel(logLevel)
+
 	dbConn, err := db.InitDB(os.Getenv("MYSQL_DB_DSN"))
 	if err != nil {
 	  logrus.WithError(err).Fatal("could not connect to db")
 	}
 
-
-
 	s, err := bot.InitBot(os.Getenv("DISCORD_BOT_TOKEN"), dbConn, os.Getenv("TEST_GUILD_ID"))
 	if err != nil {
 		logrus.WithError(err).Fatal("could not start bot")

readme.md

@@ -2,10 +2,14 @@
 
 A discord bot able to create and live update webpage embeds in channels.
 
-TODO Add example screenshot
+TODO(docs) Add Discord invite link
 
-Roadmap:
+TODO(docs) Add Website Link
 
-- [ ] Add automatic update timers
-- [ ] Support messages longer than 6000 characters
-- [ ] Support message links for update command
+TODO(docs) Add example screenshot
+
+Features:
+
+- Link existing text into discord without needing to copy and paste
+- Keep live updated messages in channel without needing to maintain them
+- Collaborate on announcement messages or documentation