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mongodb/s/d_logic.cpp

502 lines
16 KiB
C++

// d_logic.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 "stdafx.h"
#include <map>
#include <string>
#include "../db/commands.h"
#include "../db/jsobj.h"
#include "../db/dbmessage.h"
#include "../client/connpool.h"
#include "../util/queue.h"
using namespace std;
namespace mongo {
typedef map<string,unsigned long long> NSVersions;
NSVersions myVersions;
boost::thread_specific_ptr<NSVersions> clientShardVersions;
string shardConfigServer;
boost::thread_specific_ptr<OID> clientServerIds;
map< string , BlockingQueue<BSONObj>* > clientQueues;
unsigned long long getVersion( 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.date();
errmsg = "version is not a numberic type";
return 0;
}
class MongodShardCommand : public Command {
public:
MongodShardCommand( const char * n ) : Command( n ){
}
virtual bool slaveOk(){
return false;
}
virtual bool adminOnly() {
return true;
}
};
class WriteBackCommand : public MongodShardCommand {
public:
WriteBackCommand() : MongodShardCommand( "writebacklisten" ){}
bool run(const char *cmdns, BSONObj& cmdObj, string& errmsg, BSONObjBuilder& result, bool){
BSONElement e = cmdObj.firstElement();
if ( e.type() != jstOID ){
errmsg = "need oid as first value";
return 0;
}
const OID id = e.__oid();
dbtemprelease unlock;
if ( ! clientQueues[id.str()] )
clientQueues[id.str()] = new BlockingQueue<BSONObj>();
BSONObj z = clientQueues[id.str()]->blockingPop();
log(1) << "WriteBackCommand got : " << z << endl;
result.append( "data" , z );
return true;
}
} writeBackCommand;
// setShardVersion( ns )
class SetShardVersion : public MongodShardCommand {
public:
SetShardVersion() : MongodShardCommand("setShardVersion"){}
virtual void help( stringstream& help ) const {
help << " example: { setShardVersion : 'alleyinsider.foo' , version : 1 , configdb : '' } ";
}
bool run(const char *cmdns, BSONObj& cmdObj, string& errmsg, BSONObjBuilder& result, bool){
string configdb = cmdObj["configdb"].valuestrsafe();
{ // configdb checking
if ( configdb.size() == 0 ){
errmsg = "no configdb";
return false;
}
if ( shardConfigServer.size() == 0 ){
if ( ! cmdObj.getBoolField( "authoritative" ) ){
result.appendBool( "need_authoritative" , true );
errmsg = "first setShardVersion";
return false;
}
shardConfigServer = configdb;
}
else if ( shardConfigServer != configdb ){
errmsg = "specified a different configdb!";
return false;
}
}
{ // 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 ( ! clientServerIds.get() ){
string s = clientId.str();
OID * nid = new OID();
nid->init( s );
clientServerIds.reset( nid );
if ( ! clientQueues[s] )
clientQueues[s] = new BlockingQueue<BSONObj>();
}
else if ( clientId != *clientServerIds.get() ){
errmsg = "server id has changed!";
return 0;
}
}
}
unsigned long long version = getVersion( cmdObj["version"] , errmsg );
if ( ! version )
return false;
NSVersions * versions = clientShardVersions.get();
if ( ! versions ){
log(1) << "entering shard mode for connection" << endl;
versions = new NSVersions();
clientShardVersions.reset( versions );
}
string ns = cmdObj["setShardVersion"].valuestrsafe();
if ( ns.size() == 0 ){
errmsg = "need to speciy fully namespace";
return false;
}
unsigned long long& oldVersion = (*versions)[ns];
if ( version < oldVersion ){
errmsg = "you already have a newer version";
result.appendTimestamp( "oldVersion" , oldVersion );
result.appendTimestamp( "newVersion" , version );
return false;
}
unsigned long long& myVersion = myVersions[ns];
if ( version < myVersion ){
errmsg = "going to older version for global";
return false;
}
if ( myVersion == 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;
myVersion = 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' } ";
}
bool run(const char *cmdns, 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" , shardConfigServer.c_str() );
result.appendTimestamp( "global" , myVersions[ns] );
if ( clientShardVersions.get() )
result.appendTimestamp( "mine" , (*clientShardVersions.get())[ns] );
else
result.appendTimestamp( "mine" , 0 );
result.append( "ok" , 1 );
return true;
}
} getShardVersion;
class MoveShardStartCommand : public MongodShardCommand {
public:
MoveShardStartCommand() : MongodShardCommand( "movechunk.start" ){}
virtual void help( stringstream& help ) const {
help << "should not be calling this directly" << endl;
}
bool run(const char *cmdns, BSONObj& cmdObj, string& errmsg, BSONObjBuilder& result, bool){
// so i have to start clone, tell caller its ok to make change
// at this point the caller locks me, and updates config db
// then finish calls finish, and then deletes data when cursors are done
string ns = cmdObj["movechunk.start"].valuestrsafe();
string to = cmdObj["to"].valuestrsafe();
string from = cmdObj["from"].valuestrsafe(); // my public address, a tad redundant, but safe
BSONObj filter = cmdObj.getObjectField( "filter" );
if ( ns.size() == 0 ){
errmsg = "need to specify namespace in command";
return false;
}
if ( to.size() == 0 ){
errmsg = "need to specify server to move shard to";
return false;
}
if ( from.size() == 0 ){
errmsg = "need to specify server to move shard from (redundat i know)";
return false;
}
if ( filter.isEmpty() ){
errmsg = "need to specify a filter";
return false;
}
log() << "got movechunk.start: " << cmdObj << endl;
BSONObj res;
bool ok;
{
dbtemprelease unlock;
ScopedDbConnection conn( to );
ok = conn->runCommand( "admin" ,
BSON( "startCloneCollection" << ns <<
"from" << from <<
"query" << filter
) ,
res );
conn.done();
}
log() << " movechunk.start res: " << res << endl;
if ( ok ){
result.append( res["finishToken"] );
}
return ok;
}
} moveShardStartCmd;
class MoveShardFinishCommand : public MongodShardCommand {
public:
MoveShardFinishCommand() : MongodShardCommand( "movechunk.finish" ){}
virtual void help( stringstream& help ) const {
help << "should not be calling this directly" << endl;
}
bool run(const char *cmdns, BSONObj& cmdObj, string& errmsg, BSONObjBuilder& result, bool){
// see MoveShardStartCommand::run
string ns = cmdObj["movechunk.finish"].valuestrsafe();
if ( ns.size() == 0 ){
errmsg = "need ns as cmd value";
return false;
}
string to = cmdObj["to"].valuestrsafe();
if ( to.size() == 0 ){
errmsg = "need to specify server to move shard to";
return false;
}
unsigned long long newVersion = getVersion( cmdObj["newVersion"] , errmsg );
if ( newVersion == 0 ){
errmsg = "have to specify new version number";
return false;
}
BSONObj finishToken = cmdObj.getObjectField( "finishToken" );
if ( finishToken.isEmpty() ){
errmsg = "need finishToken";
return false;
}
if ( ns != finishToken["collection"].valuestrsafe() ){
errmsg = "namespaced don't match";
return false;
}
// now we're locked
myVersions[ns] = newVersion;
NSVersions * versions = clientShardVersions.get();
if ( ! versions ){
versions = new NSVersions();
clientShardVersions.reset( versions );
}
(*versions)[ns] = newVersion;
BSONObj res;
bool ok;
{
dbtemprelease unlock;
ScopedDbConnection conn( to );
ok = conn->runCommand( "admin" ,
BSON( "finishCloneCollection" << finishToken ) ,
res );
conn.done();
}
if ( ! ok ){
// uh oh
errmsg = "finishCloneCollection failed!";
result << "finishError" << res;
return false;
}
// wait until cursors are clean
cerr << "WARNING: deleting data before ensuring no more cursors TODO" << endl;
dbtemprelease unlock;
DBDirectClient client;
BSONObj removeFilter = finishToken.getObjectField( "query" );
client.remove( ns , removeFilter );
return true;
}
} moveShardFinishCmd;
bool haveLocalShardingInfo( const string& ns ){
if ( shardConfigServer.empty() )
return false;
unsigned long long version = myVersions[ns];
if ( version == 0 )
return false;
NSVersions * versions = clientShardVersions.get();
if ( ! versions )
return false;
return true;
}
/**
* @ return true if not in sharded mode
or if version for this client is ok
*/
bool shardVersionOk( const string& ns , string& errmsg ){
if ( shardConfigServer.empty() ){
return true;
}
unsigned long long version = myVersions[ns];
if ( version == 0 ){
return true;
}
NSVersions * versions = clientShardVersions.get();
if ( ! versions ){
// 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 clientVersion = (*versions)[ns];
if ( clientVersion == 0 ){
errmsg = "client in sharded mode, but doesn't have version set for this collection";
return false;
}
if ( clientVersion >= version ){
return true;
}
errmsg = "your version is too old. ";
errmsg += " ns: " + ns;
return false;
}
bool handlePossibleShardedMessage( Message &m, DbResponse &dbresponse ){
int op = m.data->operation();
if ( op < 2000 || op >= 3000 )
return false;
const char *ns = m.data->_data + 4;
string errmsg;
if ( shardVersionOk( ns , errmsg ) )
return false;
if ( doesOpGetAResponse( op ) ){
BufBuilder b( 32768 );
b.skip( sizeof( QueryResult ) );
{
BSONObj obj = BSON( "$err" << errmsg );
b.append( obj.objdata() , obj.objsize() );
}
QueryResult *qr = (QueryResult*)b.buf();
qr->resultFlags() = QueryResult::ResultFlag_ErrSet | QueryResult::ResultFlag_ShardConfigStale;
qr->len = b.len();
qr->setOperation( opReply );
qr->cursorId = 0;
qr->startingFrom = 0;
qr->nReturned = 1;
b.decouple();
Message * resp = new Message();
resp->setData( qr , true );
dbresponse.response = resp;
dbresponse.responseTo = m.data->id;
return true;
}
OID * clientID = clientServerIds.get();
massert( "write with bad shard config and no server id!" , clientID );
log() << "got write with an old config - writing back" << endl;
BSONObjBuilder b;
b.appendBool( "writeBack" , true );
b.append( "ns" , ns );
b.appendBinData( "msg" , m.data->len , bdtCustom , (char*)(m.data) );
log() << "writing back msg with len: " << m.data->len << " op: " << m.data->_operation << endl;
clientQueues[clientID->str()]->push( b.obj() );
return true;
}
}