From d102b01ee59d93de3fe18c12364ea69a85ea723f Mon Sep 17 00:00:00 2001
From: Christoph Cullmann <cullmann@kde.org>
Date: Thu, 31 Dec 2020 15:44:40 +0000
Subject: [PATCH] avoid errors for application startup if no baloo index was
 ever created

use case:

 * a KDE application started e.g. in an non-KDE Plasma environment
 * a KDE application started with baloo indexing disabled

you normally will get:

kf.kio.slaves.tags: tag fetch failed: "Failed to open the database"
kf.kio.slaves.tags: "tags:/" list() invalid url

Now this is not issued if no index database exist.
---
 src/engine/database.cpp | 6 ++++++
 src/engine/database.h   | 7 +++++++
 src/lib/taglistjob.cpp  | 7 +++++++
 3 files changed, 20 insertions(+)

diff --git a/src/engine/database.cpp b/src/engine/database.cpp
index 427210d0..ac93426c 100644
--- a/src/engine/database.cpp
+++ b/src/engine/database.cpp
@@ -247,3 +247,9 @@ QString Database::path() const
     QMutexLocker locker(&m_mutex);
     return m_path;
 }
+
+bool Database::isAvailable() const
+{
+    QMutexLocker locker(&m_mutex);
+    return QFileInfo::exists(m_path + QStringLiteral("/index"));
+}
diff --git a/src/engine/database.h b/src/engine/database.h
index 0f43b623..26d21101 100644
--- a/src/engine/database.h
+++ b/src/engine/database.h
@@ -73,6 +73,13 @@ public:
      */
     QString path() const;
 
+    /**
+     * Is the database available for use?
+     * For example if indexing is disabled or the indexer did never run this is false.
+     * @return database available
+     */
+    bool isAvailable() const;
+
 private:
     /**
      * serialize access, as open might be called from multiple threads
diff --git a/src/lib/taglistjob.cpp b/src/lib/taglistjob.cpp
index cea57889..58945cc7 100644
--- a/src/lib/taglistjob.cpp
+++ b/src/lib/taglistjob.cpp
@@ -33,7 +33,14 @@ TagListJob::~TagListJob()
 void TagListJob::start()
 {
     Database *db = globalDatabaseInstance();
+
     if (!db->open(Database::ReadOnlyDatabase)) {
+        // if we have no index, we have no tags
+        if (!db->isAvailable()) {
+            emitResult();
+            return;
+        }
+
         setError(UserDefinedError);
         setErrorText(QStringLiteral("Failed to open the database"));
         emitResult();
-- 
GitLab