looqs/shared/dbmigrator.cpp

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1.9 KiB
C++
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#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();
}