3 files changed, 41 insertions, 6 deletions

diff --git a/src/core/GpgCoreInit.cpp b/src/core/GpgCoreInit.cpp
index a5f86207..18fa2965 100644
--- a/src/core/GpgCoreInit.cpp
+++ b/src/core/GpgCoreInit.cpp
@@ -75,6 +75,7 @@ auto GetDefaultKeyDatabasePath(const QString& gpgconf_path) -> QString {
   if (GlobalSettingStation::GetInstance().IsProtableMode()) {
     default_db_path =
         GlobalSettingStation::GetInstance().GetAppDataPath() + "/db";
+    LOG_D() << "default key db in protable mode:" << default_db_path;
   } else {
     if (gpgconf_path.isEmpty()) return {};
 
@@ -516,15 +517,26 @@ auto InitGpgFrontendCore(CoreInitArgs args) -> int {
   }
 
   auto key_dbs = GetKeyDatabaseInfoBySettings();
+  assert(!key_dbs.isEmpty());
+
+  if (key_dbs.isEmpty()) {
+    FLOG_E() << "Cannot find any valid key database!"
+             << "GpgFrontend cannot start under this situation!";
+    Module::UpsertRTValue("core", "env.state.ctx", -1);
+    CoreSignalStation::GetInstance()->SignalBadGnupgEnv(
+        QCoreApplication::tr("No valid KEy Database"));
+  }
 
   // load default context
   auto& default_ctx = GpgFrontend::GpgContext::CreateInstance(
       kGpgFrontendDefaultChannel, [=]() -> ChannelObjectPtr {
         GpgFrontend::GpgContextInitArgs args;
 
-        const auto& default_key_db_info = key_dbs.front();
-        args.db_name = default_key_db_info.name;
-        args.db_path = default_key_db_info.path;
+        if (!key_dbs.isEmpty()) {
+          const auto& default_key_db_info = key_dbs.front();
+          args.db_name = default_key_db_info.name;
+          args.db_path = default_key_db_info.path;
+        }
 
         args.offline_mode = forbid_all_gnupg_connection;
         args.auto_import_missing_key = auto_import_missing_key;
diff --git a/src/core/function/GlobalSettingStation.cpp b/src/core/function/GlobalSettingStation.cpp
index 62b24331..3c0dda88 100644
--- a/src/core/function/GlobalSettingStation.cpp
+++ b/src/core/function/GlobalSettingStation.cpp
@@ -48,6 +48,15 @@ class GlobalSettingStation::Impl {
       Module::UpsertRTValue("core", "env.state.portable", 1);
       LOG_I() << "GpgFrontend runs in the portable mode now";
 
+#if defined(__linux__)
+      if (!qEnvironmentVariable("APPIMAGE").isEmpty()) {
+        LOG_I() << "app image path: " << qEnvironmentVariable("APPIMAGE");
+        QFileInfo info(
+            QString::fromUtf8(qEnvironmentVariable("APPIMAGE").toUtf8()));
+        app_path_ = info.canonicalPath();
+      }
+#endif
+
       app_data_path_ = QDir(app_path_ + "/../").canonicalPath();
       app_config_path_ = app_data_path_ + "/config";
 
@@ -197,7 +206,7 @@ class GlobalSettingStation::Impl {
   }
 
   bool portable_mode_ = false;
-  const QString app_path_ = QCoreApplication::applicationDirPath();
+  QString app_path_ = QCoreApplication::applicationDirPath();
   QString working_path_ = QDir::currentPath();
   QString app_data_path_ = QString{
       QStandardPaths::writableLocation(QStandardPaths::AppLocalDataLocation)};
diff --git a/src/core/utils/GpgUtils.cpp b/src/core/utils/GpgUtils.cpp
index ad93fe67..b8824673 100644
--- a/src/core/utils/GpgUtils.cpp
+++ b/src/core/utils/GpgUtils.cpp
@@ -289,7 +289,13 @@ auto GetCanonicalKeyDatabasePath(const QDir& app_path,
             << "to absolute path: " << target_path;
   }
 
-  auto info = QFileInfo(target_path);
+  QFileInfo info(target_path);
+  if (!info.exists()) {
+    LOG_W() << "key database not exists:" << info.canonicalFilePath()
+            << ", making a new directory...";
+    QDir().mkdir(info.canonicalFilePath());
+  }
+
   if (VerifyKeyDatabasePath(info)) {
     auto key_database_fs_path = info.canonicalFilePath();
     LOG_D() << "load gpg key database:" << key_database_fs_path;
@@ -310,10 +316,18 @@ auto GetKeyDatabaseInfoBySettings() -> QContainer<KeyDatabaseInfo> {
 
   // try to use user defined key database
   for (const auto& key_database : key_dbs) {
+    if (key_database.path.isEmpty()) continue;
+
+    LOG_D() << "got key database:" << key_database.path;
+
     auto key_database_fs_path =
         GetCanonicalKeyDatabasePath(app_path, key_database.path);
 
-    if (key_database_fs_path.isEmpty()) continue;
+    if (key_database_fs_path.isEmpty()) {
+      LOG_E() << "cannot use target path" << key_database.path
+              << "as key database";
+      continue;
+    }
 
     KeyDatabaseInfo key_db_info;
     key_db_info.name = key_database.name;