Files
mongo/s/d_state.cpp
2010-06-15 10:18:13 -04:00

361 lines
11 KiB
C++

// d_state.cpp
/**
* Copyright (C) 2008 10gen Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
these are commands that live in mongod
mostly around shard management and checking
*/
#include "pch.h"
#include <map>
#include <string>
#include "../db/commands.h"
#include "../db/jsobj.h"
#include "../db/dbmessage.h"
#include "../db/query.h"
#include "../client/connpool.h"
#include "../util/queue.h"
#include "shard.h"
#include "d_logic.h"
using namespace std;
namespace mongo {
// -----ShardingState START ----
ShardingState::ShardingState(){
_enabled = false;
}
void ShardingState::enable( const string& server ){
_enabled = true;
assert( server.size() );
if ( _configServer.size() == 0 )
_configServer = server;
else {
assert( server == _configServer );
}
}
bool ShardingState::hasVersion( const string& ns ) const {
NSVersionMap::const_iterator i = _versions.find(ns);
return i != _versions.end();
}
bool ShardingState::hasVersion( const string& ns , ConfigVersion& version ) const {
NSVersionMap::const_iterator i = _versions.find(ns);
if ( i == _versions.end() )
return false;
version = i->second;
return true;
}
ConfigVersion& ShardingState::getVersion( const string& ns ){
return _versions[ns];
}
void ShardingState::setVersion( const string& ns , const ConfigVersion& version ){
_versions[ns] = version;
}
ShardingState shardingState;
// -----ShardingState END ----
// -----ShardedConnectionInfo START ----
boost::thread_specific_ptr<ShardedConnectionInfo> ShardedConnectionInfo::_tl;
ShardedConnectionInfo::ShardedConnectionInfo(){
_id.clear();
}
ShardedConnectionInfo* ShardedConnectionInfo::get( bool create ){
ShardedConnectionInfo* info = _tl.get();
if ( ! info && create ){
log(1) << "entering shard mode for connection" << endl;
info = new ShardedConnectionInfo();
_tl.reset( info );
}
return info;
}
ConfigVersion& ShardedConnectionInfo::getVersion( const string& ns ){
return _versions[ns];
}
void ShardedConnectionInfo::setVersion( const string& ns , const ConfigVersion& version ){
_versions[ns] = version;
}
void ShardedConnectionInfo::setID( const OID& id ){
_id = id;
}
// -----ShardedConnectionInfo END ----
unsigned long long extractVersion( BSONElement e , string& errmsg ){
if ( e.eoo() ){
errmsg = "no version";
return 0;
}
if ( e.isNumber() )
return (unsigned long long)e.number();
if ( e.type() == Date || e.type() == Timestamp )
return e._numberLong();
errmsg = "version is not a numeric type";
return 0;
}
class MongodShardCommand : public Command {
public:
MongodShardCommand( const char * n ) : Command( n ){
}
virtual bool slaveOk() const {
return false;
}
virtual bool adminOnly() const {
return true;
}
};
bool haveLocalShardingInfo( const string& ns ){
if ( ! shardingState.enabled() )
return false;
if ( ! shardingState.hasVersion( ns ) )
return false;
return ShardedConnectionInfo::get(false) > 0;
}
class SetShardVersion : public MongodShardCommand {
public:
SetShardVersion() : MongodShardCommand("setShardVersion"){}
virtual void help( stringstream& help ) const {
help << " example: { setShardVersion : 'alleyinsider.foo' , version : 1 , configdb : '' } ";
}
virtual LockType locktype() const { return WRITE; } // TODO: figure out how to make this not need to lock
bool run(const string& , BSONObj& cmdObj, string& errmsg, BSONObjBuilder& result, bool){
ShardedConnectionInfo* info = ShardedConnectionInfo::get( true );
bool authoritative = cmdObj.getBoolField( "authoritative" );
string configdb = cmdObj["configdb"].valuestrsafe();
{ // configdb checking
if ( configdb.size() == 0 ){
errmsg = "no configdb";
return false;
}
if ( shardingState.enabled() ){
if ( configdb != shardingState.getConfigServer() ){
errmsg = "specified a different configdb!";
return false;
}
}
else {
if ( ! authoritative ){
result.appendBool( "need_authoritative" , true );
errmsg = "first setShardVersion";
return false;
}
shardingState.enable( configdb );
}
}
{ // setting up ids
if ( cmdObj["serverID"].type() != jstOID ){
// TODO: fix this
//errmsg = "need serverID to be an OID";
//return 0;
}
else {
OID clientId = cmdObj["serverID"].__oid();
if ( ! info->hasID() ){
info->setID( clientId );
}
else if ( clientId != info->getID() ){
errmsg = "server id has changed!";
return 0;
}
}
}
unsigned long long version = extractVersion( cmdObj["version"] , errmsg );
if ( errmsg.size() ){
return false;
}
string ns = cmdObj["setShardVersion"].valuestrsafe();
if ( ns.size() == 0 ){
errmsg = "need to speciy fully namespace";
return false;
}
ConfigVersion& oldVersion = info->getVersion(ns);
unsigned long long& globalVersion = shardingState.getVersion(ns);
if ( version == 0 && globalVersion == 0 ){
// this connection is cleaning itself
oldVersion = 0;
return 1;
}
if ( version == 0 && globalVersion > 0 ){
if ( ! authoritative ){
result.appendBool( "need_authoritative" , true );
result.appendTimestamp( "globalVersion" , globalVersion );
result.appendTimestamp( "oldVersion" , oldVersion );
errmsg = "dropping needs to be authoritative";
return 0;
}
log() << "wiping data for: " << ns << endl;
result.appendTimestamp( "beforeDrop" , globalVersion );
// only setting global version on purpose
// need clients to re-find meta-data
globalVersion = 0;
oldVersion = 0;
return 1;
}
if ( version < oldVersion ){
errmsg = "you already have a newer version";
result.appendTimestamp( "oldVersion" , oldVersion );
result.appendTimestamp( "newVersion" , version );
return false;
}
if ( version < globalVersion ){
errmsg = "going to older version for global";
return false;
}
if ( globalVersion == 0 && ! cmdObj.getBoolField( "authoritative" ) ){
// need authoritative for first look
result.appendBool( "need_authoritative" , true );
result.append( "ns" , ns );
errmsg = "first time for this ns";
return false;
}
result.appendTimestamp( "oldVersion" , oldVersion );
oldVersion = version;
globalVersion = version;
result.append( "ok" , 1 );
return 1;
}
} setShardVersion;
class GetShardVersion : public MongodShardCommand {
public:
GetShardVersion() : MongodShardCommand("getShardVersion"){}
virtual void help( stringstream& help ) const {
help << " example: { getShardVersion : 'alleyinsider.foo' } ";
}
virtual LockType locktype() const { return WRITE; } // TODO: figure out how to make this not need to lock
bool run(const string& , BSONObj& cmdObj, string& errmsg, BSONObjBuilder& result, bool){
string ns = cmdObj["getShardVersion"].valuestrsafe();
if ( ns.size() == 0 ){
errmsg = "need to speciy fully namespace";
return false;
}
result.append( "configServer" , shardingState.getConfigServer() );
result.appendTimestamp( "global" , shardingState.getVersion(ns) );
ShardedConnectionInfo* info = ShardedConnectionInfo::get( false );
if ( info )
result.appendTimestamp( "mine" , info->getVersion(ns) );
else
result.appendTimestamp( "mine" , 0 );
return true;
}
} getShardVersion;
/**
* @ return true if not in sharded mode
or if version for this client is ok
*/
bool shardVersionOk( const string& ns , string& errmsg ){
if ( ! shardingState.enabled() )
return true;
ShardedConnectionInfo* info = ShardedConnectionInfo::get( false );
if ( ! info ){
// this means the client has nothing sharded
// so this allows direct connections to do whatever they want
// which i think is the correct behavior
return true;
}
unsigned long long version;
if ( ! shardingState.hasVersion( ns , version ) )
return true;
unsigned long long clientVersion = info->getVersion(ns);
if ( version == 0 && clientVersion > 0 ){
stringstream ss;
ss << "version: " << version << " clientVersion: " << clientVersion;
errmsg = ss.str();
return false;
}
if ( clientVersion >= version )
return true;
if ( clientVersion == 0 ){
errmsg = "client in sharded mode, but doesn't have version set for this collection";
return false;
}
errmsg = (string)"your version is too old ns: " + ns;
return false;
}
}