Add delay in bulk message handler

Author: AchoArnold

api/pkg/handlers/message_handler.go

@@ -157,6 +157,11 @@ func (h *MessageHandler) BulkSend(c *fiber.Ctx) error {
 	for index, message := range params {
 		wg.Add(1)
 		go func(message services.MessageSendParams, index int) {
+			if message.SendAt == nil {
+				sentAt := time.Now().UTC().Add(time.Duration(index) * time.Second)
+				message.SendAt = &sentAt
+			}
+
 			response, err := h.service.SendMessage(ctx, message)
 			if err != nil {
 				msg := fmt.Sprintf("cannot send message with paylod [%s]", c.Body())

api/pkg/requests/message_bulk_send_request.go

@@ -40,7 +40,8 @@ func (input *MessageBulkSend) ToMessageSendParams(userID entities.UserID, source
 	from, _ := phonenumbers.Parse(input.From, phonenumbers.UNKNOWN_REGION)
 
 	var result []services.MessageSendParams
-	for _, to := range input.To {
+	for index, to := range input.To {
+		sendAt := time.Now().UTC().Add(time.Duration(index) * time.Second)
 		result = append(result, services.MessageSendParams{
 			Source:            source,
 			Owner:             from,
@@ -49,6 +50,7 @@ func (input *MessageBulkSend) ToMessageSendParams(userID entities.UserID, source
 			UserID:            userID,
 			RequestReceivedAt: time.Now().UTC(),
 			Contact:           to,
+			SendAt:            &sendAt,
 			Content:           input.Content,
 		})
 	}