diff --git a/td/telegram/ContactsManager.cpp b/td/telegram/ContactsManager.cpp
index cd9e839b5..4eb4993c5 100644
--- a/td/telegram/ContactsManager.cpp
+++ b/td/telegram/ContactsManager.cpp
@@ -1655,7 +1655,7 @@ class CheckDialogInviteLinkQuery : public Td::ResultHandler {
   void send(const string &invite_link) {
     invite_link_ = invite_link;
     send_query(G()->net_query_creator().create(
-        telegram_api::messages_checkChatInvite(ContactsManager::get_dialog_invite_link_hash(invite_link_).str())));
+        telegram_api::messages_checkChatInvite(DialogInviteLink::get_dialog_invite_link_hash(invite_link_).str())));
   }
 
   void on_result(uint64 id, BufferSlice packet) override {
@@ -1687,7 +1687,7 @@ class ImportDialogInviteLinkQuery : public Td::ResultHandler {
   void send(const string &invite_link) {
     invite_link_ = invite_link;
     send_query(G()->net_query_creator().create(
-        telegram_api::messages_importChatInvite(ContactsManager::get_dialog_invite_link_hash(invite_link).str())));
+        telegram_api::messages_importChatInvite(DialogInviteLink::get_dialog_invite_link_hash(invite_link).str())));
   }
 
   void on_result(uint64 id, BufferSlice packet) override {
@@ -2906,9 +2906,6 @@ class ContactsManager::UploadProfilePhotoCallback : public FileManager::UploadCa
   }
 };
 
-const CSlice ContactsManager::INVITE_LINK_URLS[3] = {"t.me/joinchat/", "telegram.me/joinchat/",
-                                                     "telegram.dog/joinchat/"};
-
 ContactsManager::ContactsManager(Td *td, ActorShared<> parent) : td_(td), parent_(std::move(parent)) {
   upload_profile_photo_callback_ = std::make_shared<UploadProfilePhotoCallback>();
 
@@ -6606,7 +6603,7 @@ void ContactsManager::edit_dialog_invite_link(DialogId dialog_id, const string &
 
   TRY_STATUS_PROMISE(promise, can_manage_dialog_invite_links(dialog_id));
 
-  // if (!is_valid_invite_link(invite_link)) {
+  // if (!DialogInviteLink::is_valid_invite_link(invite_link)) {
   //   return promise.set_error(Status::Error(400, "Wrong invite link"));
   // }
 
@@ -6619,7 +6616,7 @@ void ContactsManager::check_dialog_invite_link(const string &invite_link, Promis
     return promise.set_value(Unit());
   }
 
-  if (!is_valid_invite_link(invite_link)) {
+  if (!DialogInviteLink::is_valid_invite_link(invite_link)) {
     return promise.set_error(Status::Error(400, "Wrong invite link"));
   }
 
@@ -6627,7 +6624,7 @@ void ContactsManager::check_dialog_invite_link(const string &invite_link, Promis
 }
 
 void ContactsManager::import_dialog_invite_link(const string &invite_link, Promise<DialogId> &&promise) {
-  if (!is_valid_invite_link(invite_link)) {
+  if (!DialogInviteLink::is_valid_invite_link(invite_link)) {
     return promise.set_error(Status::Error(400, "Wrong invite link"));
   }
 
@@ -11485,32 +11482,6 @@ void ContactsManager::remove_dialog_access_by_invite_link(DialogId dialog_id) {
   invite_link_info_expire_timeout_.cancel_timeout(dialog_id.get());
 }
 
-bool ContactsManager::is_valid_invite_link(const string &invite_link) {
-  return !get_dialog_invite_link_hash(invite_link).empty();
-}
-
-Slice ContactsManager::get_dialog_invite_link_hash(const string &invite_link) {
-  auto lower_cased_invite_link_str = to_lower(invite_link);
-  Slice lower_cased_invite_link = lower_cased_invite_link_str;
-  size_t offset = 0;
-  if (begins_with(lower_cased_invite_link, "https://")) {
-    offset = 8;
-  } else if (begins_with(lower_cased_invite_link, "http://")) {
-    offset = 7;
-  }
-  lower_cased_invite_link.remove_prefix(offset);
-
-  for (auto &url : INVITE_LINK_URLS) {
-    if (begins_with(lower_cased_invite_link, url)) {
-      Slice hash = Slice(invite_link).substr(url.size() + offset);
-      hash.truncate(hash.find('#'));
-      hash.truncate(hash.find('?'));
-      return hash;
-    }
-  }
-  return Slice();
-}
-
 bool ContactsManager::update_invite_link(string &invite_link,
                                          tl_object_ptr<telegram_api::chatInviteExported> &&exported_chat_invite) {
   string new_invite_link;
@@ -11522,7 +11493,7 @@ bool ContactsManager::update_invite_link(string &invite_link,
     if (!invite_link.empty()) {
       invite_link_infos_.erase(invite_link);
     }
-    LOG_IF(ERROR, !new_invite_link.empty() && !is_valid_invite_link(new_invite_link))
+    LOG_IF(ERROR, !new_invite_link.empty() && !DialogInviteLink::is_valid_invite_link(new_invite_link))
         << "Unsupported invite link " << new_invite_link;
 
     invite_link = std::move(new_invite_link);
diff --git a/td/telegram/ContactsManager.h b/td/telegram/ContactsManager.h
index 3f7d57b85..e350966c4 100644
--- a/td/telegram/ContactsManager.h
+++ b/td/telegram/ContactsManager.h
@@ -221,8 +221,6 @@ class ContactsManager : public Actor {
 
   bool on_get_channel_error(ChannelId channel_id, const Status &status, const string &source);
 
-  static Slice get_dialog_invite_link_hash(const string &invite_link);
-
   void on_get_dialog_invite_link_info(const string &invite_link,
                                       tl_object_ptr<telegram_api::ChatInvite> &&chat_invite_ptr,
                                       Promise<Unit> &&promise);
@@ -1044,8 +1042,6 @@ class ContactsManager : public Actor {
   static constexpr int32 ACCOUNT_UPDATE_LAST_NAME = 1 << 1;
   static constexpr int32 ACCOUNT_UPDATE_ABOUT = 1 << 2;
 
-  static const CSlice INVITE_LINK_URLS[3];
-
   static bool have_input_peer_user(const User *u, AccessRights access_rights);
   static bool have_input_peer_chat(const Chat *c, AccessRights access_rights);
   bool have_input_peer_channel(const Channel *c, ChannelId channel_id, AccessRights access_rights,
@@ -1352,8 +1348,6 @@ class ContactsManager : public Actor {
 
   Status can_manage_dialog_invite_links(DialogId dialog_id);
 
-  static bool is_valid_invite_link(const string &invite_link);
-
   bool update_invite_link(string &invite_link, tl_object_ptr<telegram_api::chatInviteExported> &&exported_chat_invite);
 
   const DialogParticipant *get_chat_participant(ChatId chat_id, UserId user_id) const;
diff --git a/td/telegram/DialogInviteLink.cpp b/td/telegram/DialogInviteLink.cpp
index eace42662..51e5a3dec 100644
--- a/td/telegram/DialogInviteLink.cpp
+++ b/td/telegram/DialogInviteLink.cpp
@@ -9,8 +9,13 @@
 #include "td/telegram/ContactsManager.h"
 #include "td/telegram/Global.h"
 
+#include "td/utils/misc.h"
+
 namespace td {
 
+const CSlice DialogInviteLink::INVITE_LINK_URLS[3] = {"t.me/joinchat/", "telegram.me/joinchat/",
+                                                      "telegram.dog/joinchat/"};
+
 DialogInviteLink::DialogInviteLink(tl_object_ptr<telegram_api::chatInviteExported> exported_invite) {
   if (exported_invite == nullptr) {
     return;
@@ -58,6 +63,32 @@ DialogInviteLink::DialogInviteLink(tl_object_ptr<telegram_api::chatInviteExporte
   }
 }
 
+bool DialogInviteLink::is_valid_invite_link(Slice invite_link) {
+  return !get_dialog_invite_link_hash(invite_link).empty();
+}
+
+Slice DialogInviteLink::get_dialog_invite_link_hash(Slice invite_link) {
+  auto lower_cased_invite_link_str = to_lower(invite_link);
+  Slice lower_cased_invite_link = lower_cased_invite_link_str;
+  size_t offset = 0;
+  if (begins_with(lower_cased_invite_link, "https://")) {
+    offset = 8;
+  } else if (begins_with(lower_cased_invite_link, "http://")) {
+    offset = 7;
+  }
+  lower_cased_invite_link.remove_prefix(offset);
+
+  for (auto &url : INVITE_LINK_URLS) {
+    if (begins_with(lower_cased_invite_link, url)) {
+      Slice hash = invite_link.substr(url.size() + offset);
+      hash.truncate(hash.find('#'));
+      hash.truncate(hash.find('?'));
+      return hash;
+    }
+  }
+  return Slice();
+}
+
 bool DialogInviteLink::is_expired() const {
   return (expire_date_ != 0 && G()->unix_time() >= expire_date_) || (usage_limit_ != 0 && usage_count_ >= usage_limit_);
 }
diff --git a/td/telegram/DialogInviteLink.h b/td/telegram/DialogInviteLink.h
index b87d713dc..5440598d6 100644
--- a/td/telegram/DialogInviteLink.h
+++ b/td/telegram/DialogInviteLink.h
@@ -11,6 +11,7 @@
 #include "td/telegram/UserId.h"
 
 #include "td/utils/common.h"
+#include "td/utils/Slice.h"
 #include "td/utils/StringBuilder.h"
 #include "td/utils/tl_helpers.h"
 
@@ -32,11 +33,17 @@ class DialogInviteLink {
 
   friend StringBuilder &operator<<(StringBuilder &string_builder, const DialogInviteLink &invite_link);
 
+  static const CSlice INVITE_LINK_URLS[3];
+
  public:
   DialogInviteLink() = default;
 
   DialogInviteLink(tl_object_ptr<telegram_api::chatInviteExported> exported_invite);
 
+  static bool is_valid_invite_link(Slice invite_link);
+
+  static Slice get_dialog_invite_link_hash(Slice invite_link);
+
   td_api::object_ptr<td_api::chatInviteLink> get_chat_invite_link_object(const ContactsManager *contacts_manager) const;
 
   bool is_valid() const {