From ce42ff9cf74ebb8d4b68bc78c95e90ea3db02b78 Mon Sep 17 00:00:00 2001 From: Loic Blot Date: Sat, 14 May 2016 11:00:42 +0200 Subject: Implement a PostgreSQL backend --- src/database-postgresql.cpp | 286 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 286 insertions(+) create mode 100644 src/database-postgresql.cpp (limited to 'src/database-postgresql.cpp') diff --git a/src/database-postgresql.cpp b/src/database-postgresql.cpp new file mode 100644 index 000000000..3b6b42aea --- /dev/null +++ b/src/database-postgresql.cpp @@ -0,0 +1,286 @@ +/* +Copyright (C) 2016 Loic Blot + +This program is free software; you can redistribute it and/or modify +it under the terms of the GNU Lesser General Public License as published by +the Free Software Foundation; either version 2.1 of the License, or +(at your option) any later version. + +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 Lesser General Public License for more details. + +You should have received a copy of the GNU Lesser General Public License along +with this program; if not, write to the Free Software Foundation, Inc., +51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. +*/ + +#include "config.h" + +#if USE_POSTGRESQL + +#include "database-postgresql.h" + +#ifdef _WIN32 + #ifndef WIN32_LEAN_AND_MEAN + #define WIN32_LEAN_AND_MEAN + #endif + // Without this some of the network functions are not found on mingw + #ifndef _WIN32_WINNT + #define _WIN32_WINNT 0x0501 + #endif + #include + #include +#else +#include +#endif + +#include "log.h" +#include "exceptions.h" +#include "settings.h" + +Database_PostgreSQL::Database_PostgreSQL(const Settings &conf) : + m_connect_string(""), + m_conn(NULL), + m_pgversion(0) +{ + if (!conf.getNoEx("pgsql_connection", m_connect_string)) { + throw SettingNotFoundException( + "Set pgsql_connection string in world.mt to " + "use the postgresql backend\n" + "Notes:\n" + "pgsql_connection has the following form: \n" + "\tpgsql_connection = host=127.0.0.1 port=5432 user=mt_user " + "password=mt_password dbname=minetest_world\n" + "mt_user should have CREATE TABLE, INSERT, SELECT, UPDATE and " + "DELETE rights on the database.\n" + "Don't create mt_user as a SUPERUSER!"); + } + + connectToDatabase(); +} + +Database_PostgreSQL::~Database_PostgreSQL() +{ + PQfinish(m_conn); +} + +void Database_PostgreSQL::connectToDatabase() +{ + m_conn = PQconnectdb(m_connect_string.c_str()); + + if (PQstatus(m_conn) != CONNECTION_OK) { + throw DatabaseException(std::string( + "PostgreSQL database error: ") + + PQerrorMessage(m_conn)); + } + + m_pgversion = PQserverVersion(m_conn); + + /* + * We are using UPSERT feature from PostgreSQL 9.5 + * to have the better performance, + * set the minimum version to 90500 + */ + if (m_pgversion < 90500) { + throw DatabaseException("PostgreSQL database error: " + "Server version 9.5 or greater required."); + } + + infostream << "PostgreSQL Database: Version " << m_pgversion + << " Connection made." << std::endl; + + createDatabase(); + initStatements(); +} + +void Database_PostgreSQL::verifyDatabase() +{ + if (PQstatus(m_conn) == CONNECTION_OK) + return; + + PQreset(m_conn); + ping(); +} + +void Database_PostgreSQL::ping() +{ + if (PQping(m_connect_string.c_str()) != PQPING_OK) { + throw DatabaseException(std::string( + "PostgreSQL database error: ") + + PQerrorMessage(m_conn)); + } +} + +bool Database_PostgreSQL::initialized() const +{ + return (PQstatus(m_conn) == CONNECTION_OK); +} + +void Database_PostgreSQL::initStatements() +{ + prepareStatement("read_block", + "SELECT data FROM blocks " + "WHERE posX = $1::int4 AND posY = $2::int4 AND " + "posZ = $3::int4"); + + prepareStatement("write_block", + "INSERT INTO blocks (posX, posY, posZ, data) VALUES " + "($1::int4, $2::int4, $3::int4, $4::bytea) " + "ON CONFLICT ON CONSTRAINT blocks_pkey DO " + "UPDATE SET data = $4::bytea"); + + prepareStatement("delete_block", "DELETE FROM blocks WHERE " + "posX = $1::int4 AND posY = $2::int4 AND posZ = $3::int4"); + + prepareStatement("list_all_loadable_blocks", + "SELECT posX, posY, posZ FROM blocks"); +} + +PGresult *Database_PostgreSQL::checkResults(PGresult *result, bool clear) +{ + ExecStatusType statusType = PQresultStatus(result); + + switch (statusType) { + case PGRES_COMMAND_OK: + case PGRES_TUPLES_OK: + break; + case PGRES_FATAL_ERROR: + default: + throw DatabaseException( + std::string("PostgreSQL database error: ") + + PQresultErrorMessage(result)); + } + + if (clear) + PQclear(result); + + return result; +} + +void Database_PostgreSQL::createDatabase() +{ + PGresult *result = checkResults(PQexec(m_conn, + "SELECT relname FROM pg_class WHERE relname='blocks';"), + false); + + // If table doesn't exist, create it + if (!PQntuples(result)) { + static const char* dbcreate_sql = "CREATE TABLE blocks (" + "posX INT NOT NULL," + "posY INT NOT NULL," + "posZ INT NOT NULL," + "data BYTEA," + "PRIMARY KEY (posX,posY,posZ)" + ");"; + checkResults(PQexec(m_conn, dbcreate_sql)); + } + + PQclear(result); + + infostream << "PostgreSQL: Game Database was inited." << std::endl; +} + + +void Database_PostgreSQL::beginSave() +{ + verifyDatabase(); + checkResults(PQexec(m_conn, "BEGIN;")); +} + +void Database_PostgreSQL::endSave() +{ + checkResults(PQexec(m_conn, "COMMIT;")); +} + +bool Database_PostgreSQL::saveBlock(const v3s16 &pos, + const std::string &data) +{ + // Verify if we don't overflow the platform integer with the mapblock size + if (data.size() > INT_MAX) { + errorstream << "Database_PostgreSQL::saveBlock: Data truncation! " + << "data.size() over 0xFFFF (== " << data.size() + << ")" << std::endl; + return false; + } + + verifyDatabase(); + + s32 x, y, z; + x = htonl(pos.X); + y = htonl(pos.Y); + z = htonl(pos.Z); + + const void *args[] = { &x, &y, &z, data.c_str() }; + const int argLen[] = { + sizeof(x), sizeof(y), sizeof(z), (int)data.size() + }; + const int argFmt[] = { 1, 1, 1, 1 }; + + execPrepared("write_block", ARRLEN(args), args, argLen, argFmt); + return true; +} + +void Database_PostgreSQL::loadBlock(const v3s16 &pos, + std::string *block) +{ + verifyDatabase(); + + s32 x, y, z; + x = htonl(pos.X); + y = htonl(pos.Y); + z = htonl(pos.Z); + + const void *args[] = { &x, &y, &z }; + const int argLen[] = { sizeof(x), sizeof(y), sizeof(z) }; + const int argFmt[] = { 1, 1, 1 }; + + PGresult *results = execPrepared("read_block", ARRLEN(args), args, + argLen, argFmt, false); + + *block = ""; + + if (PQntuples(results)) { + *block = std::string(PQgetvalue(results, 0, 0), + PQgetlength(results, 0, 0)); + } + + PQclear(results); +} + +bool Database_PostgreSQL::deleteBlock(const v3s16 &pos) +{ + verifyDatabase(); + + s32 x, y, z; + x = htonl(pos.X); + y = htonl(pos.Y); + z = htonl(pos.Z); + + const void *args[] = { &x, &y, &z }; + const int argLen[] = { sizeof(x), sizeof(y), sizeof(z) }; + const int argFmt[] = { 1, 1, 1 }; + + execPrepared("read_block", ARRLEN(args), args, argLen, argFmt); + + return true; +} + +void Database_PostgreSQL::listAllLoadableBlocks(std::vector &dst) +{ + verifyDatabase(); + + PGresult *results = execPrepared("list_all_loadable_blocks", 0, + NULL, NULL, NULL, false, false); + + int numrows = PQntuples(results); + + for (int row = 0; row < numrows; ++row) { + dst.push_back(pg_to_v3s16(results, 0, 0)); + } + + PQclear(results); +} + +#endif // USE_POSTGRESQL -- cgit v1.2.3