set DB schema version programmatically in a centralized way, use exceptions when things go wrong

resources/sql/db_init_sqlite.sql

@@ -3,8 +3,6 @@ CREATE TABLE Information (
   inf_value       TEXT
 );
 -- !
-INSERT INTO Information VALUES ('schema_version', '2');
--- !
 CREATE TABLE Accounts (
   id              $$,
   type            TEXT        NOT NULL CHECK (type != ''), /* ID of the account type. Each account defines its own, for example 'ttrss'. */

resources/sql/db_update_sqlite_1_2.sql

@@ -26,6 +26,4 @@ INSERT INTO Feeds (id, title, description, date_created, icon, category, source,
 SELECT id, title, description, date_created, icon, category, source, update_type, update_interval, account_id, custom_id, custom_data
 FROM backup_Feeds;
 -- !
-DROP TABLE backup_Feeds;
+DROP TABLE backup_Feeds;
--- !
-UPDATE Information SET inf_value = '2' WHERE inf_key = 'schema_version';

src/librssguard/database/databasedriver.cpp

@@ -14,28 +14,23 @@
 DatabaseDriver::DatabaseDriver(QObject* parent) : QObject(parent)
 {}
 
-bool DatabaseDriver::updateDatabaseSchema(QSqlQuery& query,
+void DatabaseDriver::updateDatabaseSchema(QSqlQuery& query,
                                           int source_db_schema_version,
                                           const QString& database_name) {
   const int current_version = QSL(APP_DB_SCHEMA_VERSION).toInt();
 
   while (source_db_schema_version != current_version) {
-    try {
+    const QStringList statements = prepareScript(APP_SQL_PATH,
-      const QStringList statements = prepareScript(APP_SQL_PATH,
+                                                 QSL(APP_DB_UPDATE_FILE_PATTERN).arg(ddlFilePrefix(),
-                                                   QSL(APP_DB_UPDATE_FILE_PATTERN).arg(ddlFilePrefix(),
+                                                                                     QString::number(source_db_schema_version),
-                                                                                       QString::number(source_db_schema_version),
+                                                                                     QString::number(source_db_schema_version + 1)),
-                                                                                       QString::number(source_db_schema_version + 1)),
+                                                 database_name);
-                                                   database_name);
 
-      for (const QString& statement : statements) {
+    for (const QString& statement : statements) {
-        if (!query.exec(statement) && query.lastError().isValid()) {
+      if (!query.exec(statement) && query.lastError().isValid()) {
-          throw ApplicationException(query.lastError().text());
+        throw ApplicationException(query.lastError().text());
-        }
       }
     }
-    catch (const ApplicationException& ex) {
-      qFatal("Error when running SQL scripts: %s.", qPrintable(ex.message()));
-    }
 
     // Increment the version.
     qDebugNN << LOGSEC_DB
@@ -47,7 +42,20 @@ bool DatabaseDriver::updateDatabaseSchema(QSqlQuery& query,
     source_db_schema_version++;
   }
 
-  return true;
+  setSchemaVersion(query, current_version, false);
+}
+
+void DatabaseDriver::setSchemaVersion(QSqlQuery& query, int new_schema_version, bool empty_table) {
+  if (!query.prepare(empty_table
+                     ? QSL("INSERT INTO Information VALUES ('schema_version', :schema_version);")
+                     : QSL("UPDATE Information SET inf_value = :schema_version WHERE inf_key = 'schema_version';"))) {
+    throw ApplicationException(query.lastError().text());
+  }
+
+  query.bindValue(QSL(":schema_version"), QString::number(new_schema_version));
+  if (!query.exec()) {
+    throw ApplicationException(query.lastError().text());
+  }
 }
 
 QStringList DatabaseDriver::prepareScript(const QString& base_sql_folder,

src/librssguard/database/databasedriver.h

@@ -46,10 +46,12 @@ class DatabaseDriver : public QObject {
                                     DatabaseDriver::DesiredStorageType desired_type = DatabaseDriver::DesiredStorageType::FromSettings) = 0;
 
   protected:
-    bool updateDatabaseSchema(QSqlQuery& query,
+    void updateDatabaseSchema(QSqlQuery& query,
                               int source_db_schema_version,
                               const QString& database_name = {});
 
+    void setSchemaVersion(QSqlQuery& query, int new_schema_version, bool empty_table);
+
     QStringList prepareScript(const QString& base_sql_folder,
                               const QString& sql_file,
                               const QString& database_name = {});

src/librssguard/database/mariadbdriver.cpp

@@ -183,6 +183,8 @@ QSqlDatabase MariaDbDriver::initializeDatabase(const QString& connection_name) {
             throw ApplicationException(query_db.lastError().text());
           }
         }
+
+        setSchemaVersion(query_db, QSL(APP_DB_SCHEMA_VERSION).toInt(), true);
       }
       catch (const ApplicationException& ex) {
         qFatal("Error when running SQL scripts: %s.", qPrintable(ex.message()));
@@ -196,18 +198,17 @@ QSqlDatabase MariaDbDriver::initializeDatabase(const QString& connection_name) {
       const int installed_db_schema = query_db.value(0).toString().toInt();
 
       if (installed_db_schema < QSL(APP_DB_SCHEMA_VERSION).toInt()) {
-        if (updateDatabaseSchema(query_db, installed_db_schema, database_name)) {
+        try {
+          updateDatabaseSchema(query_db, installed_db_schema, database_name);
           qDebugNN << LOGSEC_DB
                    << "Database schema was updated from"
                    << QUOTE_W_SPACE(installed_db_schema)
                    << "to"
                    << QUOTE_W_SPACE(APP_DB_SCHEMA_VERSION)
-                   << "successully or it is already up to date.";
+                   << "successully.";
         }
-        else {
+        catch (const ApplicationException& ex) {
-          qFatal("Database schema was not updated from '%s' to '%s' successully.",
+          qFatal("Error when updating DB schema from %d: %s.", installed_db_schema, qPrintable(ex.message()));
-                 qPrintable(QString::number(installed_db_schema)),
-                 APP_DB_SCHEMA_VERSION);
         }
       }
     }

src/librssguard/database/sqlitedriver.cpp

@@ -254,6 +254,8 @@ QSqlDatabase SqliteDriver::initializeDatabase(const QString& connection_name, bo
             throw ApplicationException(query_db.lastError().text());
           }
         }
+
+        setSchemaVersion(query_db, QSL(APP_DB_SCHEMA_VERSION).toInt(), true);
       }
       catch (const ApplicationException& ex) {
         qFatal("Error when running SQL scripts: %s.", qPrintable(ex.message()));
@@ -274,18 +276,17 @@ QSqlDatabase SqliteDriver::initializeDatabase(const QString& connection_name, bo
           qFatal("Creation of backup SQLite DB file failed.");
         }
 
-        if (updateDatabaseSchema(query_db, installed_db_schema)) {
+        try {
+          updateDatabaseSchema(query_db, installed_db_schema);
           qDebugNN << LOGSEC_DB
-                   << "Database schema was updated from '"
+                   << "Database schema was updated from"
-                   << installed_db_schema
+                   << QUOTE_W_SPACE(installed_db_schema)
-                   << "' to '"
+                   << "to"
-                   << APP_DB_SCHEMA_VERSION
+                   << QUOTE_W_SPACE(APP_DB_SCHEMA_VERSION)
-                   << "' successully or it is already up to date.";
+                   << "successully.";
         }
-        else {
+        catch (const ApplicationException& ex) {
-          qFatal("Database schema was not updated from '%s' to '%s' successully.",
+          qFatal("Error when updating DB schema from %d: %s.", installed_db_schema, qPrintable(ex.message()));
-                 qPrintable(QString::number(installed_db_schema)),
-                 APP_DB_SCHEMA_VERSION);
         }
       }