src/database-redis.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2014 celeron55, Perttu Ahola <celeron55@gmail.com>
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU Lesser General Public License as published by
   7 the Free Software Foundation; either version 2.1 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public License along
  16 with this program; if not, write to the Free Software Foundation, Inc.,
  17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "config.h"
  21
  22 #if USE_REDIS
  23 /*
  24         Redis databases
  25 */
  26
  27
  28 #include "database-redis.h"
  29 #include <hiredis.h>
  30
  31 #include "map.h"
  32 #include "mapsector.h"
  33 #include "mapblock.h"
  34 #include "serialization.h"
  35 #include "main.h"
  36 #include "settings.h"
  37 #include "log.h"
  38
  39 Database_Redis::Database_Redis(ServerMap *map, std::string savedir)
  40 {
  41         Settings conf;
  42         conf.readConfigFile((std::string(savedir) + DIR_DELIM + "world.mt").c_str());
  43         std::string tmp;
  44         try {
  45         tmp = conf.get("redis_address");
  46         hash = conf.get("redis_hash");
  47         } catch(SettingNotFoundException e) {
  48                 throw SettingNotFoundException("Set redis_address and redis_hash in world.mt to use the redis backend");
  49         }
  50         const char *addr = tmp.c_str();
  51         int port = conf.exists("redis_port") ? conf.getU16("redis_port") : 6379;
  52         ctx = redisConnect(addr, port);
  53         if(!ctx)
  54                 throw FileNotGoodException("Cannot allocate redis context");
  55         else if(ctx->err) {
  56                 std::string err = std::string("Connection error: ") + ctx->errstr;
  57                 redisFree(ctx);
  58                 throw FileNotGoodException(err);
  59         }
  60         srvmap = map;
  61 }
  62
  63 int Database_Redis::Initialized(void)
  64 {
  65         return 1;
  66 }
  67
  68 void Database_Redis::beginSave() {
  69         redisReply *reply;
  70         reply = (redisReply*) redisCommand(ctx, "MULTI");
  71         if(!reply)
  72                 throw FileNotGoodException(std::string("redis command 'MULTI' failed: ") + ctx->errstr);
  73         freeReplyObject(reply);
  74 }
  75
  76 void Database_Redis::endSave() {
  77         redisReply *reply;
  78         reply = (redisReply*) redisCommand(ctx, "EXEC");
  79         if(!reply)
  80                 throw FileNotGoodException(std::string("redis command 'EXEC' failed: ") + ctx->errstr);
  81         freeReplyObject(reply);
  82 }
  83
  84 void Database_Redis::saveBlock(MapBlock *block)
  85 {
  86         DSTACK(__FUNCTION_NAME);
  87         /*
  88                 Dummy blocks are not written
  89         */
  90         if(block->isDummy())
  91         {
  92                 return;
  93         }
  94
  95         // Format used for writing
  96         u8 version = SER_FMT_VER_HIGHEST_WRITE;
  97         // Get destination
  98         v3s16 p3d = block->getPos();
  99
 100         /*
 101                 [0] u8 serialization version
 102                 [1] data
 103         */
 104
 105         std::ostringstream o(std::ios_base::binary);
 106         o.write((char*)&version, 1);
 107         // Write basic data
 108         block->serialize(o, version, true);
 109         // Write block to database
 110         std::string tmp1 = o.str();
 111         std::string tmp2 = i64tos(getBlockAsInteger(p3d));
 112
 113         redisReply *reply;
 114         reply = (redisReply*) redisCommand(ctx, "HSET %s %s %b", hash.c_str(), tmp2.c_str(), tmp1.c_str(), tmp1.size());
 115         if(!reply)
 116                 throw FileNotGoodException(std::string("redis command 'HSET %s %s %b' failed: ") + ctx->errstr);
 117         if(reply->type == REDIS_REPLY_ERROR)
 118                 throw FileNotGoodException("Failed to store block in Database");
 119
 120         // We just wrote it to the disk so clear modified flag
 121         block->resetModified();
 122 }
 123
 124 MapBlock* Database_Redis::loadBlock(v3s16 blockpos)
 125 {
 126         v2s16 p2d(blockpos.X, blockpos.Z);
 127
 128         std::string tmp = i64tos(getBlockAsInteger(blockpos));
 129         redisReply *reply;
 130         reply = (redisReply*) redisCommand(ctx, "HGET %s %s", hash.c_str(), tmp.c_str());
 131         if(!reply)
 132                 throw FileNotGoodException(std::string("redis command 'HGET %s %s' failed: ") + ctx->errstr);
 133
 134         if (reply->type == REDIS_REPLY_STRING && reply->len == 0) {
 135                 freeReplyObject(reply);
 136                 errorstream << "Blank block data in database (reply->len == 0) ("
 137                         << blockpos.X << "," << blockpos.Y << "," << blockpos.Z << ")" << std::endl;
 138
 139                 if (g_settings->getBool("ignore_world_load_errors")) {
 140                         errorstream << "Ignoring block load error. Duck and cover! "
 141                                 << "(ignore_world_load_errors)" << std::endl;
 142                 } else {
 143                         throw SerializationError("Blank block data in database");
 144                 }
 145                 return NULL;
 146         }
 147
 148         if (reply->type == REDIS_REPLY_STRING) {
 149                 /*
 150                         Make sure sector is loaded
 151                 */
 152                 MapSector *sector = srvmap->createSector(p2d);
 153
 154                 try {
 155                         std::istringstream is(std::string(reply->str, reply->len), std::ios_base::binary);
 156                         freeReplyObject(reply); // std::string copies the memory so we can already do this here
 157                         u8 version = SER_FMT_VER_INVALID;
 158                         is.read((char *)&version, 1);
 159
 160                         if (is.fail())
 161                                 throw SerializationError("ServerMap::loadBlock(): Failed"
 162                                         " to read MapBlock version");
 163
 164                         MapBlock *block = NULL;
 165                         bool created_new = false;
 166                         block = sector->getBlockNoCreateNoEx(blockpos.Y);
 167                         if (block == NULL)
 168                         {
 169                                 block = sector->createBlankBlockNoInsert(blockpos.Y);
 170                                 created_new = true;
 171                         }
 172
 173                         // Read basic data
 174                         block->deSerialize(is, version, true);
 175
 176                         // If it's a new block, insert it to the map
 177                         if (created_new)
 178                                 sector->insertBlock(block);
 179
 180                         // We just loaded it from, so it's up-to-date.
 181                         block->resetModified();
 182                 }
 183                 catch (SerializationError &e)
 184                 {
 185                         errorstream << "Invalid block data in database"
 186                                 << " (" << blockpos.X << "," << blockpos.Y << "," << blockpos.Z
 187                                 << ") (SerializationError): " << e.what() << std::endl;
 188                         // TODO: Block should be marked as invalid in memory so that it is
 189                         // not touched but the game can run
 190
 191                         if (g_settings->getBool("ignore_world_load_errors")) {
 192                                 errorstream << "Ignoring block load error. Duck and cover! "
 193                                         << "(ignore_world_load_errors)" << std::endl;
 194                         } else {
 195                                 throw SerializationError("Invalid block data in database");
 196                         }
 197                 }
 198
 199                 return srvmap->getBlockNoCreateNoEx(blockpos);  // should not be using this here
 200         }
 201         return NULL;
 202 }
 203
 204 void Database_Redis::listAllLoadableBlocks(std::list<v3s16> &dst)
 205 {
 206         redisReply *reply;
 207         reply = (redisReply*) redisCommand(ctx, "HKEYS %s", hash.c_str());
 208         if(!reply)
 209                 throw FileNotGoodException(std::string("redis command 'HKEYS %s' failed: ") + ctx->errstr);
 210         if(reply->type != REDIS_REPLY_ARRAY)
 211                 throw FileNotGoodException("Failed to get keys from database");
 212         for(size_t i = 0; i < reply->elements; i++)
 213         {
 214                 assert(reply->element[i]->type == REDIS_REPLY_STRING);
 215                 dst.push_back(getIntegerAsBlock(stoi64(reply->element[i]->str)));
 216         }
 217         freeReplyObject(reply);
 218 }
 219
 220 Database_Redis::~Database_Redis()
 221 {
 222         redisFree(ctx);
 223 }
 224 #endif