src/Configuration.h
author František Kučera <franta-hg@frantovo.cz>
Thu, 04 Jun 2020 00:46:00 +0200
branchv_0
changeset 47 428c278af4be
parent 37 3de41719d7eb
child 59 a1775ba6d056
permissions -rw-r--r--
rename option --data-source-url to --data-source-string In some implementations like JDBC, the connection string is URL, but in ODBC the string is not formally URL, so it is better to use more general term „data source string“ instead of URL. - data source name (DSN) = name of a pre-configured database connection that should be looked-up in configuration and used - data source string (connection string) = arbitrary string containing (in certain encoding which might and might not be URL) all needed parameters (e.g. server name + port + user name + password) Name and string might sometimes be also combined: in ODBC we can e.g. connect to a string: DSN=relpipe;someParameter=foo;someOther=bar which will lookup configuration for the „relpipe“ data source and will combine it with given parameters.

/**
 * Relational pipes
 * Copyright © 2019 František Kučera (Frantovo.cz, GlobalCode.info)
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, version 3.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
#pragma once

#include <relpipe/writer/AttributeMetadata.h>
#include <relpipe/writer/typedefs.h>

namespace relpipe {
namespace tr {
namespace sql {

class Parameter {
public:

	relpipe::writer::string_t value;
	// TODO: relpipe::writer::TypeId type;
};

class TypeCast {
public:

	relpipe::writer::string_t name;
	relpipe::writer::string_t type;
};

class Statement {
public:

	virtual ~Statement() {
	}

	/**
	 * output relation name;
	 * if empty, the SQL code (DML, DDL) will be executed, but no relational output will be generated
	 */
	relpipe::writer::string_t relation;
	/**
	 * SQL code, usually some SELECT;
	 * might be also DML or DDL
	 */
	relpipe::writer::string_t sql;
	/**
	 * Explicitly defined types of particular attributes.
	 * SQLite uses dynamic typing, so it is often impossible to obtain the proper types from the result set.
	 */
	std::vector<TypeCast> typeCasts;
	/**
	 * Query parameters
	 */
	std::vector<Parameter> parameters;
};

/**
 * Allows copying relations from the input stream to the output stream.
 * Such relations are specified by a regular expression.
 * We can also specify the regex replacement string and rename such relations. 
 */
class CopyRelations {
public:

	CopyRelations(const relpipe::writer::string_t pattern, const relpipe::writer::string_t replacement, const relpipe::writer::boolean_t replace) : pattern(pattern), replacement(replacement), replace(replace) {
	}

	virtual ~CopyRelations() {
	}

	const relpipe::writer::string_t pattern;
	const relpipe::writer::string_t replacement;
	const relpipe::writer::boolean_t replace;
};

class Configuration {
public:


	relpipe::writer::string_t dataSourceName;
	
	relpipe::writer::string_t dataSourceString;

	std::vector<Statement> statements;

	/**
	 * SQL script to be executed before the relational input.
	 */
	std::wistream* sqlBeforeRelational = nullptr;

	/**
	 * SQL script to be executed after the relational input.
	 */
	std::wistream* sqlAfterRelational = nullptr;

	std::vector<CopyRelations> copyRelations;
	
	relpipe::writer::boolean_t listDataSources = false;

	virtual ~Configuration() {
	}
};

}
}
}