// SendBatch implements batch.Sender.
func (ls *LocalSender) SendBatch(ctx context.Context, ba proto.BatchRequest) (*proto.BatchResponse, error) {
trace := tracer.FromCtx(ctx)
var store *storage.Store
var err error
// If we aren't given a Replica, then a little bending over
// backwards here. This case applies exclusively to unittests.
if ba.RangeID == 0 || ba.Replica.StoreID == 0 {
var repl *proto.Replica
var rangeID proto.RangeID
rangeID, repl, err = ls.lookupReplica(ba.Key, ba.EndKey)
if err == nil {
ba.RangeID = rangeID
ba.Replica = *repl
}
}
ctx = log.Add(ctx,
log.Method, ba.Method(), // TODO(tschottdorf): Method() always `Batch`.
log.Key, ba.Key,
log.RangeID, ba.RangeID)
if err == nil {
store, err = ls.GetStore(ba.Replica.StoreID)
}
var br *proto.BatchResponse
if err == nil {
// For calls that read data within a txn, we can avoid uncertainty
// related retries in certain situations. If the node is in
// "CertainNodes", we need not worry about uncertain reads any
// more. Setting MaxTimestamp=Timestamp for the operation
// accomplishes that. See proto.Transaction.CertainNodes for details.
if ba.Txn != nil && ba.Txn.CertainNodes.Contains(ba.Replica.NodeID) {
// MaxTimestamp = Timestamp corresponds to no clock uncertainty.
trace.Event("read has no clock uncertainty")
ba.Txn.MaxTimestamp = ba.Txn.Timestamp
}
{
var tmpR proto.Response
// TODO(tschottdorf): &ba -> ba
tmpR, err = store.ExecuteCmd(ctx, &ba)
// TODO(tschottdorf): remove this dance once BatchResponse is returned.
if tmpR != nil {
br = tmpR.(*proto.BatchResponse)
if br.Error != nil {
panic(proto.ErrorUnexpectedlySet)
}
}
}
}
// TODO(tschottdorf): Later error needs to be associated to an index
// and ideally individual requests don't even have an error in their
// header. See #1891.
return br, err
}