big refactoring

bot/queue/queue.go

@@ -0,0 +1,101 @@
+package queue
+
+import (
+	"strconv"
+)
+
+// Add to queue
+func (q *Queue) Add(id, from, to, data string) error {
+	itemkey := acQueueKey + "." + id
+	item := map[string]string{
+		"attempts": "0",
+		"data":     data,
+		"from":     from,
+		"to":       to,
+		"id":       id,
+	}
+
+	q.mu.Lock(itemkey)
+	defer q.mu.Unlock(itemkey)
+	err := q.lp.SetAccountData(itemkey, item)
+	if err != nil {
+		q.log.Error("cannot enqueue email id=%q: %v", id, err)
+		return err
+	}
+
+	q.mu.Lock(acQueueKey)
+	defer q.mu.Unlock(acQueueKey)
+	queueIndex, err := q.lp.GetAccountData(acQueueKey)
+	if err != nil {
+		q.log.Error("cannot get queue index: %v", err)
+		return err
+	}
+	queueIndex[id] = itemkey
+	err = q.lp.SetAccountData(acQueueKey, queueIndex)
+	if err != nil {
+		q.log.Error("cannot save queue index: %v", err)
+		return err
+	}
+
+	return nil
+}
+
+// Remove from queue
+func (q *Queue) Remove(id string) error {
+	index, err := q.lp.GetAccountData(acQueueKey)
+	if err != nil {
+		q.log.Error("cannot get queue index: %v", err)
+		return err
+	}
+	itemkey := index[id]
+	if itemkey == "" {
+		itemkey = acQueueKey + "." + id
+	}
+	delete(index, id)
+	err = q.lp.SetAccountData(acQueueKey, index)
+	if err != nil {
+		q.log.Error("cannot update queue index: %v", err)
+		return err
+	}
+
+	q.mu.Lock(itemkey)
+	defer q.mu.Unlock(itemkey)
+	return q.lp.SetAccountData(itemkey, nil)
+}
+
+// try to send email
+func (q *Queue) try(itemkey string, maxRetries int) bool {
+	q.mu.Lock(itemkey)
+	defer q.mu.Unlock(itemkey)
+
+	item, err := q.lp.GetAccountData(itemkey)
+	if err != nil {
+		q.log.Error("cannot retrieve a queue item %q: %v", itemkey, err)
+		return false
+	}
+	q.log.Debug("processing queue item %+v", item)
+	attempts, err := strconv.Atoi(item["attempts"])
+	if err != nil {
+		q.log.Error("cannot parse attempts of %q: %v", itemkey, err)
+		return false
+	}
+	if attempts > maxRetries {
+		return true
+	}
+
+	err = q.sendmail(item["from"], item["to"], item["data"])
+	if err == nil {
+		q.log.Debug("email %q from queue was delivered")
+		return true
+	}
+
+	q.log.Debug("attempted to deliver email id=%q, retry=%q, but it's not ready yet: %v", item["id"], item["attempts"], err)
+	attempts++
+	item["attempts"] = strconv.Itoa(attempts)
+	err = q.lp.SetAccountData(itemkey, item)
+	if err != nil {
+		q.log.Error("cannot update attempt count on email %q: %v", itemkey, err)
+	}
+
+	return false
+}