/**
* The core config write functionality.
*
* Config writes run in two passes - the first is a quick check to ensure the config servers
* are all reachable, the second runs the actual write.
*
* TODO: Upgrade and move this logic to the config servers, a state machine implementation
* is probably the next step.
*/
void ConfigCoordinator::executeBatch( const BatchedCommandRequest& clientRequest,
BatchedCommandResponse* clientResponse,
bool fsyncCheck ) {
NamespaceString nss( clientRequest.getNS() );
dassert( nss.db() == "config" || nss.db() == "admin" );
dassert( clientRequest.sizeWriteOps() == 1u );
if ( fsyncCheck ) {
//
// Sanity check that all configs are still reachable using fsync, preserving legacy
// behavior
//
OwnedPointerVector<ConfigFsyncResponse> fsyncResponsesOwned;
vector<ConfigFsyncResponse*>& fsyncResponses = fsyncResponsesOwned.mutableVector();
//
// Send side
//
for ( vector<ConnectionString>::iterator it = _configHosts.begin();
it != _configHosts.end(); ++it ) {
ConnectionString& configHost = *it;
FsyncRequest fsyncRequest;
_dispatcher->addCommand( configHost, "admin", fsyncRequest );
}
_dispatcher->sendAll();
//
// Recv side
//
bool fsyncError = false;
while ( _dispatcher->numPending() > 0 ) {
fsyncResponses.push_back( new ConfigFsyncResponse() );
ConfigFsyncResponse& fsyncResponse = *fsyncResponses.back();
Status dispatchStatus = _dispatcher->recvAny( &fsyncResponse.configHost,
&fsyncResponse.response );
// We've got to recv everything, no matter what
if ( !dispatchStatus.isOK() ) {
fsyncError = true;
buildFsyncErrorFrom( dispatchStatus, &fsyncResponse.response );
}
else if ( !fsyncResponse.response.getOk() ) {
fsyncError = true;
}
}
if ( fsyncError ) {
combineFsyncErrors( fsyncResponses, clientResponse );
return;
}
else {
fsyncResponsesOwned.clear();
}
}
//
// Do the actual writes
//
BatchedCommandRequest configRequest( clientRequest.getBatchType() );
clientRequest.cloneTo( &configRequest );
configRequest.setNS( nss.coll() );
OwnedPointerVector<ConfigResponse> responsesOwned;
vector<ConfigResponse*>& responses = responsesOwned.mutableVector();
//
// Send the actual config writes
//
// Get as many batches as we can at once
for ( vector<ConnectionString>::iterator it = _configHosts.begin();
it != _configHosts.end(); ++it ) {
ConnectionString& configHost = *it;
_dispatcher->addCommand( configHost, nss.db(), configRequest );
}
// Send them all out
_dispatcher->sendAll();
//
// Recv side
//
while ( _dispatcher->numPending() > 0 ) {
// Get the response
responses.push_back( new ConfigResponse() );
ConfigResponse& configResponse = *responses.back();
Status dispatchStatus = _dispatcher->recvAny( &configResponse.configHost,
&configResponse.response );
if ( !dispatchStatus.isOK() ) {
buildErrorFrom( dispatchStatus, &configResponse.response );
}
}
combineResponses( responses, clientResponse );
}
/**
* The core config write functionality.
*
* Config writes run in two passes - the first is a quick check to ensure the config servers
* are all reachable, the second runs the actual write.
*
* TODO: Upgrade and move this logic to the config servers, a state machine implementation
* is probably the next step.
*/
void ConfigCoordinator::executeBatch(const BatchedCommandRequest& clientRequest,
BatchedCommandResponse* clientResponse) {
const NamespaceString nss(clientRequest.getNS());
// Should never use it for anything other than DBs residing on the config server
dassert(nss.db() == "config" || nss.db() == "admin");
dassert(clientRequest.sizeWriteOps() == 1u);
// This is an opportunistic check that all config servers look healthy by calling
// getLastError on each one of them. If there was some form of write/journaling error, get
// last error would fail.
{
for (vector<ConnectionString>::iterator it = _configHosts.begin();
it != _configHosts.end();
++it) {
_dispatcher->addCommand(*it,
"admin",
RawBSONSerializable(BSON("getLastError" << true <<
"fsync" << true)));
}
_dispatcher->sendAll();
bool error = false;
while (_dispatcher->numPending()) {
ConnectionString host;
RawBSONSerializable response;
Status status = _dispatcher->recvAny(&host, &response);
if (status.isOK()) {
BSONObj obj = response.toBSON();
LOG(3) << "Response " << obj.toString();
// If the ok field is anything other than 1, count it as error
if (!obj["ok"].trueValue()) {
error = true;
log() << "Config server check for host " << host
<< " returned error: " << response;
}
}
else {
error = true;
log() << "Config server check for host " << host
<< " failed with status: " << status;
}
}
// All responses should have been gathered by this point
if (error) {
clientResponse->setOk(false);
clientResponse->setErrCode(ErrorCodes::RemoteValidationError);
clientResponse->setErrMessage("Could not verify that config servers were active"
" and reachable before write");
return;
}
}
if (!_checkConfigString(clientResponse)) {
return;
}
//
// Do the actual writes
//
BatchedCommandRequest configRequest( clientRequest.getBatchType() );
clientRequest.cloneTo( &configRequest );
configRequest.setNS( nss.coll() );
OwnedPointerVector<ConfigResponse> responsesOwned;
vector<ConfigResponse*>& responses = responsesOwned.mutableVector();
//
// Send the actual config writes
//
// Get as many batches as we can at once
for (vector<ConnectionString>::const_iterator it = _configHosts.begin();
it != _configHosts.end();
++it) {
const ConnectionString& configHost = *it;
_dispatcher->addCommand(configHost, nss.db(), configRequest);
}
// Send them all out
_dispatcher->sendAll();
//
// Recv side
//
while (_dispatcher->numPending() > 0) {
// Get the response
responses.push_back(new ConfigResponse());
ConfigResponse& configResponse = *responses.back();
Status dispatchStatus = _dispatcher->recvAny(&configResponse.configHost,
&configResponse.response);
if (!dispatchStatus.isOK()) {
buildErrorFrom(dispatchStatus, &configResponse.response);
}
}
combineResponses(responses, clientResponse);
}