AutoGetCollectionForRead::AutoGetCollectionForRead(OperationContext* txn,
const NamespaceString& nss)
: _txn(txn), _transaction(txn, MODE_IS) {
{
_autoColl.emplace(txn, nss, MODE_IS);
auto curOp = CurOp::get(_txn);
stdx::lock_guard<Client> lk(*_txn->getClient());
// TODO: OldClientContext legacy, needs to be removed
curOp->ensureStarted();
curOp->setNS_inlock(nss.ns());
// At this point, we are locked in shared mode for the database by the DB lock in the
// constructor, so it is safe to load the DB pointer.
if (_autoColl->getDb()) {
// TODO: OldClientContext legacy, needs to be removed
curOp->enter_inlock(nss.ns().c_str(), _autoColl->getDb()->getProfilingLevel());
}
}
// Note: this can yield.
_ensureMajorityCommittedSnapshotIsValid(nss);
// We have both the DB and collection locked, which is the prerequisite to do a stable shard
// version check, but we'd like to do the check after we have a satisfactory snapshot.
auto css = CollectionShardingState::get(txn, nss);
css->checkShardVersionOrThrow(txn);
}
AutoGetCollectionForRead::AutoGetCollectionForRead(OperationContext* opCtx,
const NamespaceString& nss,
AutoGetCollection::ViewMode viewMode) {
_autoColl.emplace(opCtx, nss, MODE_IS, MODE_IS, viewMode);
// Note: this can yield.
_ensureMajorityCommittedSnapshotIsValid(nss, opCtx);
}