Golang BatchRequest.Replica方法代码示例

// Send forwards the call to the single store. This is a poor man's
// version of kv.TxnCoordSender, but it serves the purposes of
// supporting tests in this package. Transactions are not supported.
// Since kv/ depends on storage/, we can't get access to a
// TxnCoordSender from here.
// TODO(tschottdorf): {kv->storage}.LocalSender
func (db *testSender) Send(ctx context.Context, ba roachpb.BatchRequest) (*roachpb.BatchResponse, *roachpb.Error) {
	if et, ok := ba.GetArg(roachpb.EndTransaction); ok {
		return nil, roachpb.NewError(util.Errorf("%s method not supported", et.Method()))
	}
	// Lookup range and direct request.
	key, endKey := keys.Range(ba)
	rng := db.store.LookupReplica(key, endKey)
	if rng == nil {
		return nil, roachpb.NewError(roachpb.NewRangeKeyMismatchError(key, endKey, nil))
	}
	ba.RangeID = rng.Desc().RangeID
	replica := rng.GetReplica()
	if replica == nil {
		return nil, roachpb.NewError(util.Errorf("own replica missing in range"))
	}
	ba.Replica = *replica
	br, pErr := db.store.Send(ctx, ba)
	if br != nil && br.Error != nil {
		panic(roachpb.ErrorUnexpectedlySet(db.store, br))
	}
	if pErr != nil {
		return nil, pErr
	}
	return br, nil
}

// Send implements the client.Sender interface. The store is looked up from the
// store map if specified by the request; otherwise, the command is being
// executed locally, and the replica is determined via lookup through each
// store's LookupRange method. The latter path is taken only by unit tests.
func (ls *Stores) Send(ctx context.Context, ba roachpb.BatchRequest) (*roachpb.BatchResponse, *roachpb.Error) {
	var store *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 *roachpb.ReplicaDescriptor
		var rangeID roachpb.RangeID
		rs := keys.Range(ba)
		rangeID, repl, err = ls.lookupReplica(rs.Key, rs.EndKey)
		if err == nil {
			ba.RangeID = rangeID
			ba.Replica = *repl
		}
	}

	ctx = log.Add(ctx,
		log.RangeID, ba.RangeID)

	if err == nil {
		store, err = ls.GetStore(ba.Replica.StoreID)
	}

	if err != nil {
		return nil, roachpb.NewError(err)
	}

	sp, cleanupSp := tracing.SpanFromContext(opStores, store.Tracer(), ctx)
	defer cleanupSp()
	if ba.Txn != nil {
		// For calls that read data within a txn, we keep track of timestamps
		// observed from the various participating nodes' HLC clocks. If we have
		// a timestamp on file for this Node which is smaller than MaxTimestamp,
		// we can lower MaxTimestamp accordingly. If MaxTimestamp drops below
		// OrigTimestamp, we effectively can't see uncertainty restarts any
		// more.
		// Note that it's not an issue if MaxTimestamp propagates back out to
		// the client via a returned Transaction update - when updating a Txn
		// from another, the larger MaxTimestamp wins.
		if maxTS, ok := ba.Txn.GetObservedTimestamp(ba.Replica.NodeID); ok && maxTS.Less(ba.Txn.MaxTimestamp) {
			// Copy-on-write to protect others we might be sharing the Txn with.
			shallowTxn := *ba.Txn
			// The uncertainty window is [OrigTimestamp, maxTS), so if that window
			// is empty, there won't be any uncertainty restarts.
			if !ba.Txn.OrigTimestamp.Less(maxTS) {
				sp.LogEvent("read has no clock uncertainty")
			}
			shallowTxn.MaxTimestamp.Backward(maxTS)
			ba.Txn = &shallowTxn
		}
	}
	br, pErr := store.Send(ctx, ba)
	if br != nil && br.Error != nil {
		panic(roachpb.ErrorUnexpectedlySet(store, br))
	}
	return br, pErr
}

// Send implements the client.Sender interface. The store is looked up from the
// store map if specified by the request; otherwise, the command is being
// executed locally, and the replica is determined via lookup through each
// store's LookupRange method. The latter path is taken only by unit tests.
func (ls *Stores) Send(ctx context.Context, ba roachpb.BatchRequest) (*roachpb.BatchResponse, *roachpb.Error) {
	sp := tracing.SpanFromContext(ctx)
	var store *Store
	var pErr *roachpb.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 *roachpb.ReplicaDescriptor
		var rangeID roachpb.RangeID
		rs := keys.Range(ba)
		rangeID, repl, pErr = ls.lookupReplica(rs.Key, rs.EndKey)
		if pErr == nil {
			ba.RangeID = rangeID
			ba.Replica = *repl
		}
	}

	ctx = log.Add(ctx,
		log.RangeID, ba.RangeID)

	if pErr == nil {
		store, pErr = ls.GetStore(ba.Replica.StoreID)
	}

	var br *roachpb.BatchResponse
	if pErr != nil {
		return nil, pErr
	}
	// 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=OrigTimestamp for the operation
	// accomplishes that. See roachpb.Transaction.CertainNodes for details.
	if ba.Txn != nil && ba.Txn.CertainNodes.Contains(ba.Replica.NodeID) {
		// MaxTimestamp = Timestamp corresponds to no clock uncertainty.
		sp.LogEvent("read has no clock uncertainty")
		// Copy-on-write to protect others we might be sharing the Txn with.
		shallowTxn := *ba.Txn
		// We set to OrigTimestamp because that works for both SNAPSHOT and
		// SERIALIZABLE: If we used Timestamp instead, we could run into
		// unnecessary retries at SNAPSHOT. For example, a SNAPSHOT txn at
		// OrigTimestamp = 1000.0, Timestamp = 2000.0, MaxTimestamp = 3000.0
		// will always read at 1000, so a MaxTimestamp of 2000 will still let
		// it restart with uncertainty when it finds a value in (1000, 2000).
		shallowTxn.MaxTimestamp = ba.Txn.OrigTimestamp
		ba.Txn = &shallowTxn
	}
	br, pErr = store.Send(ctx, ba)
	if br != nil && br.Error != nil {
		panic(roachpb.ErrorUnexpectedlySet(store, br))
	}
	return br, pErr
}

// Send implements the client.Sender interface. The store is looked up from the
// store map if specified by the request; otherwise, the command is being
// executed locally, and the replica is determined via lookup through each
// store's LookupRange method. The latter path is taken only by unit tests.
func (ls *Stores) Send(ctx context.Context, ba roachpb.BatchRequest) (*roachpb.BatchResponse, *roachpb.Error) {
	sp := tracing.SpanFromContext(ctx)
	var store *Store
	var pErr *roachpb.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 *roachpb.ReplicaDescriptor
		var rangeID roachpb.RangeID
		rs := keys.Range(ba)
		rangeID, repl, pErr = ls.lookupReplica(rs.Key, rs.EndKey)
		if pErr == nil {
			ba.RangeID = rangeID
			ba.Replica = *repl
		}
	}

	ctx = log.Add(ctx,
		log.RangeID, ba.RangeID)

	if pErr == nil {
		store, pErr = ls.GetStore(ba.Replica.StoreID)
	}

	var br *roachpb.BatchResponse
	if pErr != nil {
		return nil, pErr
	}
	// 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 roachpb.Transaction.CertainNodes for details.
	if ba.Txn != nil && ba.Txn.CertainNodes.Contains(ba.Replica.NodeID) {
		// MaxTimestamp = Timestamp corresponds to no clock uncertainty.
		sp.LogEvent("read has no clock uncertainty")
		// Copy-on-write to protect others we might be sharing the Txn with.
		shallowTxn := *ba.Txn
		shallowTxn.MaxTimestamp = ba.Txn.Timestamp
		ba.Txn = &shallowTxn
	}
	br, pErr = store.Send(ctx, ba)
	if br != nil && br.Error != nil {
		panic(roachpb.ErrorUnexpectedlySet(store, br))
	}
	return br, pErr
}

// Send implements the client.Sender interface. The store is looked up from the
// store map if specified by the request; otherwise, the command is being
// executed locally, and the replica is determined via lookup through each
// store's LookupRange method. The latter path is taken only by unit tests.
func (ls *LocalSender) Send(ctx context.Context, ba roachpb.BatchRequest) (*roachpb.BatchResponse, *roachpb.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 *roachpb.ReplicaDescriptor
		var rangeID roachpb.RangeID
		key, endKey := keys.Range(ba)
		rangeID, repl, err = ls.lookupReplica(key, endKey)
		if err == nil {
			ba.RangeID = rangeID
			ba.Replica = *repl
		}
	}

	ctx = log.Add(ctx,
		log.RangeID, ba.RangeID)

	if err == nil {
		store, err = ls.GetStore(ba.Replica.StoreID)
	}

	var br *roachpb.BatchResponse
	if err != nil {
		return nil, roachpb.NewError(err)
	}
	// 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 roachpb.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
	}
	br, pErr := store.Send(ctx, ba)
	if br != nil && br.Error != nil {
		panic(roachpb.ErrorUnexpectedlySet(store, br))
	}
	return br, pErr
}

func TestStoreExecuteNoop(t *testing.T) {
	defer leaktest.AfterTest(t)
	store, _, stopper := createTestStore(t)
	defer stopper.Stop()
	ba := roachpb.BatchRequest{}
	ba.Key = nil // intentional
	ba.RangeID = 1
	ba.Replica = roachpb.ReplicaDescriptor{StoreID: store.StoreID()}
	ba.Add(&roachpb.GetRequest{RequestHeader: roachpb.RequestHeader{Key: roachpb.Key("a")}})
	ba.Add(&roachpb.NoopRequest{})

	br, pErr := store.Send(context.Background(), ba)
	if pErr != nil {
		t.Error(pErr)
	}
	reply := br.Responses[1].GetInner()
	if _, ok := reply.(*roachpb.NoopResponse); !ok {
		t.Errorf("expected *roachpb.NoopResponse, got %T", reply)
	}
}

// sendRPC sends one or more RPCs to replicas from the supplied roachpb.Replica
// slice. First, replicas which have gossiped addresses are corralled (and
// rearranged depending on proximity and whether the request needs to go to a
// leader) and then sent via rpc.Send, with requirement that one RPC to a
// server must succeed. Returns an RPC error if the request could not be sent.
// Note that the reply may contain a higher level error and must be checked in
// addition to the RPC error.
func (ds *DistSender) sendRPC(trace *tracer.Trace, rangeID roachpb.RangeID, replicas replicaSlice, order rpc.OrderingPolicy,
	ba roachpb.BatchRequest) (*roachpb.BatchResponse, *roachpb.Error) {
	if len(replicas) == 0 {
		return nil, roachpb.NewError(noNodeAddrsAvailError{})
	}

	// Build a slice of replica addresses.
	addrs := make([]net.Addr, 0, len(replicas))
	replicaMap := make(map[string]*roachpb.ReplicaDescriptor, len(replicas))
	for i := range replicas {
		addr := replicas[i].NodeDesc.Address
		addrs = append(addrs, addr)
		replicaMap[addr.String()] = &replicas[i].ReplicaDescriptor
	}

	// TODO(pmattis): This needs to be tested. If it isn't set we'll
	// still route the request appropriately by key, but won't receive
	// RangeNotFoundErrors.
	ba.RangeID = rangeID

	// Set RPC opts with stipulation that one of N RPCs must succeed.
	rpcOpts := rpc.Options{
		N:               1,
		Ordering:        order,
		SendNextTimeout: defaultSendNextTimeout,
		Timeout:         defaultRPCTimeout,
		Trace:           trace,
	}
	// getArgs clones the arguments on demand for all but the first replica.
	firstArgs := true
	getArgs := func(addr net.Addr) proto.Message {
		var a *roachpb.BatchRequest
		// Use the supplied args proto if this is our first address.
		if firstArgs {
			firstArgs = false
			a = &ba
		} else {
			// Otherwise, copy the args value and set the replica in the header.
			a = proto.Clone(&ba).(*roachpb.BatchRequest)
		}
		if addr != nil {
			// TODO(tschottdorf): see len(replicas) above.
			a.Replica = *replicaMap[addr.String()]
		}
		return a
	}
	// RPCs are sent asynchronously and there is no synchronized access to
	// the reply object, so we don't pass itself to RPCSend.
	// Otherwise there maybe a race case:
	// If the RPC call times out using our original reply object,
	// we must not use it any more; the rpc call might still return
	// and just write to it at any time.
	// args.CreateReply() should be cheaper than proto.Clone which use reflect.
	getReply := func() proto.Message {
		return &roachpb.BatchResponse{}
	}

	const method = "Node.Batch"
	replies, err := ds.rpcSend(rpcOpts, method, addrs, getArgs, getReply, ds.rpcContext)
	if err != nil {
		return nil, roachpb.NewError(err)
	}
	return replies[0].(*roachpb.BatchResponse), nil
}