shared: Begin db migration logic

Issue: #26

shared/create.qrc

@@ -1,5 +0,0 @@
-<!DOCTYPE RCC><RCC version="1.0">
-<qresource>
-    <file>create.sql</file>
-</qresource>
-</RCC>

shared/dbmigrator.cpp

@@ -0,0 +1,85 @@
+#include <QDirIterator>
+#include <QSqlQuery>
+#include <QSqlError>
+#include <QTextStream>
+#include <QDebug>
+#include "dbmigrator.h"
+#include "looqsgeneralexception.h"
+
+DBMigrator::DBMigrator(QSqlDatabase &db)
+{
+	Q_INIT_RESOURCE(migrations);
+	this->db = &db;
+}
+
+DBMigrator::~DBMigrator()
+{
+	Q_CLEANUP_RESOURCE(migrations);
+}
+
+QStringList DBMigrator::getMigrationFilenames()
+{
+	QStringList result;
+	QDirIterator it(":/looqs-migrations/");
+	while(it.hasNext())
+	{
+		result.append(it.next());
+	}
+	return result;
+}
+
+uint32_t DBMigrator::currentRevision()
+{
+	QSqlQuery dbquery(*db);
+	dbquery.exec("PRAGMA user_version;");
+	if(!dbquery.next())
+	{
+		throw new LooqsGeneralException("Failed to query current db revision");
+	}
+	uint32_t result = dbquery.value(0).toUInt();
+	return result;
+}
+
+bool DBMigrator::migrationNeeded()
+{
+	QStringList migrations = getMigrationFilenames();
+	uint32_t currentRev = currentRevision();
+
+	return currentRev < static_cast<uint32_t>(migrations.size());
+}
+
+void DBMigrator::performMigrations()
+{
+	QStringList migrations = getMigrationFilenames();
+	uint32_t currentRev = currentRevision();
+	uint32_t targetRev = (migrations.size());
+
+	for(uint32_t i = currentRev + 1; i <= targetRev; i++)
+	{
+		QString fileName = QString(":/looqs-migrations/%1.sql").arg(i);
+		QFile file{fileName};
+		if(!file.open(QIODevice::ReadOnly))
+		{
+			throw LooqsGeneralException("Migration: Failed to find required revision file");
+		}
+		QTextStream stream(&file);
+		db->transaction();
+		while(!stream.atEnd())
+		{
+			QString sql = stream.readLine();
+			QSqlQuery sqlQuery{*db};
+			if(!sqlQuery.exec(sql))
+			{
+
+				db->rollback();
+				throw LooqsGeneralException("Failed to execute sql statement while initializing database: " +
+											sqlQuery.lastError().text());
+			}
+		}
+		QSqlQuery updateVersion{*db};
+		updateVersion.exec(QString("PRAGMA user_version=%1;").arg(i));
+		db->commit();
+		emit migrationDone(i);
+	}
+	emit done();
+}

shared/dbmigrator.h

@@ -0,0 +1,24 @@
+#ifndef DBMIGRATOR_H
+#define DBMIGRATOR_H
+#include <QStringList>
+#include <QSqlDatabase>
+#include <QObject>
+class DBMigrator : public QObject
+{
+	Q_OBJECT
+  private:
+	QSqlDatabase *db;
+
+  public:
+	DBMigrator(QSqlDatabase &db);
+	~DBMigrator();
+	uint32_t currentRevision();
+	void performMigrations();
+	QStringList getMigrationFilenames();
+	bool migrationNeeded();
+  signals:
+	void migrationDone(uint32_t);
+	void done();
+};
+
+#endif // DBMIGRATOR_H

shared/migrations/migrations.qrc

@@ -0,0 +1,5 @@
+<RCC>
+    <qresource prefix="/looqs-migrations">
+        <file>1.sql</file>
+    </qresource>
+</RCC>

shared/shared.pro

@@ -27,12 +27,18 @@ DEFINES += QT_DEPRECATED_WARNINGS
 #DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0
 
 SOURCES += sqlitesearch.cpp \
+    databasefactory.cpp \
+    dbmigrator.cpp \
+    logger.cpp \
     looqsgeneralexception.cpp \
     common.cpp \
     looqsquery.cpp
 
 HEADERS += sqlitesearch.h \
+    databasefactory.h \
+    dbmigrator.h \
     filedata.h \
+    logger.h \
     looqsgeneralexception.h \
     looqsquery.h \
     searchresult.h \
@@ -42,4 +48,4 @@ unix {
     target.path = /usr/lib
     INSTALLS += target
 }
-RESOURCES = create.qrc
+RESOURCES = migrations/migrations.qrc