hyperion.ng/include/db/DBManager.h
Paulchen-Panther c676b640f1
unique sql database connection is created on different threads
Signed-off-by: Paulchen-Panther <Paulchen-Panter@protonmail.com>
2019-08-03 19:14:52 +02:00

131 lines
4.7 KiB
C++

#pragma once
#include <utils/Logger.h>
#include <QMap>
#include <QVariant>
#include <QPair>
#include <QVector>
class QSqlDatabase;
class QSqlQuery;
typedef QPair<QString,QVariant> CPair;
typedef QVector<CPair> VectorPair;
///
/// @brief Database interface for SQLite3.
/// Inherit this class to create component specific methods based on this interface
/// Usage: setTable(name) once before you use read/write actions
/// To use another database use setDb(newDB) (defaults to "hyperion")
///
/// Incompatible functions with SQlite3:
/// QSqlQuery::size() returns always -1
///
class DBManager : public QObject
{
Q_OBJECT
public:
DBManager(QObject* parent = nullptr);
~DBManager();
/// set root path
void setRootPath(const QString& rootPath);
/// define the database to work with
void setDatabaseName(const QString& dbn) { _dbn = dbn; };
/// set a table to work with
void setTable(const QString& table);
/// get current database object set with setDB()
QSqlDatabase getDB() const;
///
/// @brief Create a table (if required) with the given columns. Older tables will be updated accordingly with missing columns
/// Does not delete or migrate old columns
/// @param[in] columns The columns of the table. Requires at least one entry!
/// @return True on success else false
///
bool createTable(QStringList& columns) const;
///
/// @brief Create a column if the column already exists returns false and logs error
/// @param[in] column The column of the table
/// @return True on success else false
///
bool createColumn(const QString& column) const;
///
/// @brief Check if at least one record exists in table with the conditions
/// @param[in] conditions The search conditions (WHERE)
/// @return True on success else false
///
bool recordExists(const VectorPair& conditions) const;
///
/// @brief Create a new record in table when the conditions find no existing entry. Add additional key:value pairs in columns
/// DO NOT repeat column keys between 'conditions' and 'columns' as they will be merged on creation
/// @param[in] conditions conditions to search for, as a record may exist and should be updated instead (WHERE)
/// @param[in] columns columns to create or update (optional)
/// @return True on success else false
///
bool createRecord(const VectorPair& conditions, const QVariantMap& columns = QVariantMap()) const;
///
/// @brief Update a record with conditions and additional key:value pairs in columns
/// @param[in] conditions conditions which rows should be updated (WHERE)
/// @param[in] columns columns to update
/// @return True on success else false
///
bool updateRecord(const VectorPair& conditions, const QVariantMap& columns) const;
///
/// @brief Get data of a single record, multiple records are not supported
/// @param[in] conditions condition to search for (WHERE)
/// @param[out] results results of query
/// @param[in] tColumns target columns to search in (optional) if not provided returns all columns
/// @return True on success else false
///
bool getRecord(const VectorPair& conditions, QVariantMap& results, const QStringList& tColumns = QStringList()) const;
///
/// @brief Get data of multiple records, you need to specify the columns. This search is without conditions. Good to grab all data from db
/// @param[in] conditions condition to search for (WHERE)
/// @param[out] results results of query
/// @param[in] tColumns target columns to search in (optional) if not provided returns all columns
/// @return True on success else false
///
bool getRecords(QVector<QVariantMap>& results, const QStringList& tColumns = QStringList()) const;
///
/// @brief Delete a record determined by conditions
/// @param[in] conditions conditions of the row to delete it (WHERE)
/// @return True on success; on error or not found false
///
bool deleteRecord(const VectorPair& conditions) const;
///
/// @brief Check if table exists in current database
/// @param[in] table The name of the table
/// @return True on success else false
///
bool tableExists(const QString& table) const;
///
/// @brief Delete a table, fails silent (return true) if table is not found
/// @param[in] table The name of the table
/// @return True on success else false
///
bool deleteTable(const QString& table) const;
private:
Logger* _log;
/// databse connection & file name, defaults to hyperion
QString _dbn = "hyperion";
/// table in database
QString _table;
/// addBindValue to query given by QVariantList
void doAddBindValue(QSqlQuery& query, const QVariantList& variants) const;
};