refactor(datatransfer): xerrors, cbor-gen, tweaks

Various refactors per PR comments: use xerrors, add context to dt calls, use cbor-gen, move files
into seperate modules, etc

chain/deals/cbor_gen.go

@@ -851,3 +851,51 @@ func (t *MinerDeal) UnmarshalCBOR(r io.Reader) error {
 	t.SectorID = uint64(extra)
 	return nil
 }
+
+func (t *StorageDataTransferVoucher) MarshalCBOR(w io.Writer) error {
+	if t == nil {
+		_, err := w.Write(cbg.CborNull)
+		return err
+	}
+	if _, err := w.Write([]byte{129}); err != nil {
+		return err
+	}
+
+	// t.t.Proposal (cid.Cid)
+
+	if err := cbg.WriteCid(w, t.Proposal); err != nil {
+		return xerrors.Errorf("failed to write cid field t.Proposal: %w", err)
+	}
+
+	return nil
+}
+
+func (t *StorageDataTransferVoucher) UnmarshalCBOR(r io.Reader) error {
+	br := cbg.GetPeeker(r)
+
+	maj, extra, err := cbg.CborReadHeader(br)
+	if err != nil {
+		return err
+	}
+	if maj != cbg.MajArray {
+		return fmt.Errorf("cbor input should be of type array")
+	}
+
+	if extra != 1 {
+		return fmt.Errorf("cbor input had wrong number of fields")
+	}
+
+	// t.t.Proposal (cid.Cid)
+
+	{
+
+		c, err := cbg.ReadCid(br)
+		if err != nil {
+			return xerrors.Errorf("failed to read cid field t.Proposal: %w", err)
+		}
+
+		t.Proposal = c
+
+	}
+	return nil
+}

chain/deals/client_utils.go

@@ -1,17 +1,28 @@
 package deals
 
 import (
+	"bytes"
 	"context"
+	"reflect"
 	"runtime"
 
 	"github.com/ipfs/go-cid"
+	"github.com/ipfs/go-datastore"
+	"github.com/ipfs/go-datastore/namespace"
 	files "github.com/ipfs/go-ipfs-files"
 	unixfile "github.com/ipfs/go-unixfs/file"
+	"github.com/ipld/go-ipld-prime"
+	"github.com/libp2p/go-libp2p-core/peer"
+	"go.uber.org/fx"
 	"golang.org/x/xerrors"
 
+	"github.com/filecoin-project/lotus/datatransfer"
 	"github.com/filecoin-project/lotus/lib/cborutil"
 	"github.com/filecoin-project/lotus/lib/padreader"
 	"github.com/filecoin-project/lotus/lib/sectorbuilder"
+	"github.com/filecoin-project/lotus/lib/statestore"
+	"github.com/filecoin-project/lotus/node/modules/dtypes"
+
 )
 
 func (c *Client) failDeal(id cid.Cid, cerr error) {
@@ -98,3 +109,81 @@ func (c *Client) disconnect(deal ClientDeal) error {
 	delete(c.conns, deal.ProposalCid)
 	return err
 }
+
+var _ datatransfer.RequestValidator = &ClientRequestValidator{}
+
+// ClientRequestValidator validates data transfer requests for the client
+// in a storage market
+type ClientRequestValidator struct {
+	deals *statestore.StateStore
+}
+
+// RegisterClientValidator is an initialization hook that registers the client
+// request validator with the data transfer module as the validator for
+// StorageDataTransferVoucher types
+func RegisterClientValidator(lc fx.Lifecycle, crv *ClientRequestValidator, dtm datatransfer.ClientDataTransfer) {
+	lc.Append(fx.Hook{
+		OnStart: func(ctx context.Context) error {
+			return dtm.RegisterVoucherType(reflect.TypeOf(StorageDataTransferVoucher{}), crv)
+		},
+	})
+}
+
+// NewClientRequestValidator returns a new client request validator for the
+// given datastore
+func NewClientRequestValidator(ds dtypes.MetadataDS) *ClientRequestValidator {
+	crv := &ClientRequestValidator{
+		deals: statestore.New(namespace.Wrap(ds, datastore.NewKey("/deals/client"))),
+	}
+	return crv
+}
+
+// ValidatePush validates a push request received from the peer that will send data
+// Will always error because clients should not accept push requests from a provider
+// in a storage deal (i.e. send data to client).
+func (c *ClientRequestValidator) ValidatePush(
+	sender peer.ID,
+	voucher datatransfer.Voucher,
+	baseCid cid.Cid,
+	Selector ipld.Node) error {
+	return ErrNoPushAccepted
+}
+
+// ValidatePull validates a pull request received from the peer that will receive data
+// Will succeed only if:
+// - voucher has correct type
+// - voucher references an active deal
+// - referenced deal matches the receiver (miner)
+// - referenced deal matches the given base CID
+// - referenced deal is in an acceptable state
+func (c *ClientRequestValidator) ValidatePull(
+	receiver peer.ID,
+	voucher datatransfer.Voucher,
+	baseCid cid.Cid,
+	Selector ipld.Node) error {
+	dealVoucher, ok := voucher.(*StorageDataTransferVoucher)
+	if !ok {
+		return xerrors.Errorf("voucher type %s: %w", voucher.Identifier(), ErrWrongVoucherType)
+	}
+
+	var deal ClientDeal
+	err := c.deals.Mutate(dealVoucher.Proposal, func(d *ClientDeal) error {
+		deal = *d
+		return nil
+	})
+	if err != nil {
+		return xerrors.Errorf("Proposal CID %s: %w", dealVoucher.Proposal.String(), ErrNoDeal)
+	}
+	if deal.Miner != receiver {
+		return xerrors.Errorf("Deal Peer %s, Data Transfer Peer %s: %w", deal.Miner.String(), receiver.String(), ErrWrongPeer)
+	}
+	if !bytes.Equal(deal.Proposal.PieceRef, baseCid.Bytes()) {
+		return xerrors.Errorf("Deal Payload CID %s, Data Transfer CID %s: %w", string(deal.Proposal.PieceRef), baseCid.String(), ErrWrongPiece)
+	}
+	for _, state := range AcceptableDealStates {
+		if deal.State == state {
+			return nil
+		}
+	}
+	return xerrors.Errorf("Deal State %s: %w", deal.State, ErrInacceptableDealState)
+}

chain/deals/provider.go

@@ -212,7 +212,7 @@ func (p *Provider) onUpdated(ctx context.Context, update minerDealUpdate) {
 // and update message for the deal -- either moving to staged for a completion
 // event or moving to error if a data transfer error occurs
 func (p *Provider) onDataTransferEvent(event datatransfer.Event, channelState datatransfer.ChannelState) {
-	voucher, ok := channelState.Voucher().(StorageDataTransferVoucher)
+	voucher, ok := channelState.Voucher().(*StorageDataTransferVoucher)
 	// if this event is for a transfer not related to storage, ignore
 	if !ok {
 		return

chain/deals/provider_states.go

@@ -163,8 +163,9 @@ func (p *Provider) accept(ctx context.Context, deal MinerDeal) (func(*MinerDeal)
 	// initiate a pull data transfer. This will complete asynchronously and the
 	// completion of the data transfer will trigger a change in deal state
 	// (see onDataTransferEvent)
-	_, err = p.dataTransfer.OpenPullDataChannel(deal.Client,
+	_, err = p.dataTransfer.OpenPullDataChannel(ctx,
-		StorageDataTransferVoucher{Proposal: deal.ProposalCid},
+		deal.Client,
+		&StorageDataTransferVoucher{Proposal: deal.ProposalCid},
 		deal.Ref,
 		allSelector,
 	)

chain/deals/provider_utils.go

@@ -1,17 +1,28 @@
 package deals
 
 import (
+	"bytes"
 	"context"
+	"reflect"
 	"runtime"
 
 	"github.com/filecoin-project/lotus/api"
+	"github.com/filecoin-project/lotus/datatransfer"
+	"github.com/filecoin-project/lotus/node/modules/dtypes"
+	"github.com/ipld/go-ipld-prime"
+	"go.uber.org/fx"
+
 	"github.com/filecoin-project/lotus/chain/actors"
 	"github.com/filecoin-project/lotus/chain/address"
 	"github.com/filecoin-project/lotus/chain/types"
 	"github.com/filecoin-project/lotus/lib/cborutil"
+	"github.com/filecoin-project/lotus/lib/statestore"
 
 	"github.com/ipfs/go-cid"
+	"github.com/ipfs/go-datastore"
+	"github.com/ipfs/go-datastore/namespace"
 	inet "github.com/libp2p/go-libp2p-core/network"
+	"github.com/libp2p/go-libp2p-core/peer"
 	"golang.org/x/xerrors"
 )
 
@@ -125,3 +136,81 @@ func (p *Provider) getWorker(miner address.Address) (address.Address, error) {
 
 	return address.NewFromBytes(r.Return)
 }
+
+var _ datatransfer.RequestValidator = &ProviderRequestValidator{}
+
+// ProviderRequestValidator validates data transfer requests for the provider
+// in a storage market
+type ProviderRequestValidator struct {
+	deals *statestore.StateStore
+}
+
+// RegisterProviderValidator is an initialization hook that registers the provider
+// request validator with the data transfer module as the validator for
+// StorageDataTransferVoucher types
+func RegisterProviderValidator(lc fx.Lifecycle, mrv *ProviderRequestValidator, dtm datatransfer.ProviderDataTransfer) {
+	lc.Append(fx.Hook{
+		OnStart: func(ctx context.Context) error {
+			return dtm.RegisterVoucherType(reflect.TypeOf(StorageDataTransferVoucher{}), mrv)
+		},
+	})
+}
+
+// NewProviderRequestValidator returns a new client request validator for the
+// given datastore
+func NewProviderRequestValidator(ds dtypes.MetadataDS) *ProviderRequestValidator {
+	return &ProviderRequestValidator{
+		deals: statestore.New(namespace.Wrap(ds, datastore.NewKey("/deals/client"))),
+	}
+}
+
+// ValidatePush validates a push request received from the peer that will send data
+// Will succeed only if:
+// - voucher has correct type
+// - voucher references an active deal
+// - referenced deal matches the client
+// - referenced deal matches the given base CID
+// - referenced deal is in an acceptable state
+func (m *ProviderRequestValidator) ValidatePush(
+	sender peer.ID,
+	voucher datatransfer.Voucher,
+	baseCid cid.Cid,
+	Selector ipld.Node) error {
+	dealVoucher, ok := voucher.(*StorageDataTransferVoucher)
+	if !ok {
+		return xerrors.Errorf("voucher type %s: %w", voucher.Identifier(), ErrWrongVoucherType)
+	}
+
+	var deal MinerDeal
+	err := m.deals.Mutate(dealVoucher.Proposal, func(d *MinerDeal) error {
+		deal = *d
+		return nil
+	})
+	if err != nil {
+		return xerrors.Errorf("Proposal CID %s: %w", dealVoucher.Proposal.String(), ErrNoDeal)
+	}
+	if deal.Client != sender {
+		return xerrors.Errorf("Deal Peer %s, Data Transfer Peer %s: %w", deal.Client.String(), sender.String(), ErrWrongPeer)
+	}
+
+	if !bytes.Equal(deal.Proposal.PieceRef, baseCid.Bytes()) {
+		return xerrors.Errorf("Deal Payload CID %s, Data Transfer CID %s: %w", string(deal.Proposal.PieceRef), baseCid.String(), ErrWrongPiece)
+	}
+	for _, state := range AcceptableDealStates {
+		if deal.State == state {
+			return nil
+		}
+	}
+	return xerrors.Errorf("Deal State %s: %w", deal.State, ErrInacceptableDealState)
+}
+
+// ValidatePull validates a pull request received from the peer that will receive data.
+// Will always error because providers should not accept pull requests from a client
+// in a storage deal (i.e. send data to client).
+func (m *ProviderRequestValidator) ValidatePull(
+	receiver peer.ID,
+	voucher datatransfer.Voucher,
+	baseCid cid.Cid,
+	Selector ipld.Node) error {
+	return ErrNoPullAccepted
+}

chain/deals/request_validation.go

@@ -1,230 +0,0 @@
-package deals
-
-import (
-	"bytes"
-	"context"
-	"errors"
-	"reflect"
-
-	"github.com/ipfs/go-cid"
-	datastore "github.com/ipfs/go-datastore"
-	"github.com/ipfs/go-datastore/namespace"
-	"github.com/ipld/go-ipld-prime"
-	"github.com/libp2p/go-libp2p-core/peer"
-	"go.uber.org/fx"
-
-	"github.com/filecoin-project/lotus/api"
-	"github.com/filecoin-project/lotus/datatransfer"
-	"github.com/filecoin-project/lotus/lib/statestore"
-	"github.com/filecoin-project/lotus/node/modules/dtypes"
-)
-
-var (
-	// ErrWrongVoucherType means the voucher was not the correct type can validate against
-	ErrWrongVoucherType = errors.New("cannot validate voucher type")
-
-	// ErrNoPushAccepted just means clients do not accept pushes for storage deals
-	ErrNoPushAccepted = errors.New("Client should not receive data for a storage deal")
-
-	// ErrNoPullAccepted just means providers do not accept pulls for storage deals
-	ErrNoPullAccepted = errors.New("Provider should not send data for a storage deal")
-
-	// ErrNoDeal means no active deal was found for this vouchers proposal cid
-	ErrNoDeal = errors.New("No deal found for this proposal")
-
-	// ErrWrongPeer means that the other peer for this data transfer request does not match
-	// the other peer for the deal
-	ErrWrongPeer = errors.New("Data Transfer peer id and Deal peer id do not match")
-
-	// ErrWrongPiece means that the pieceref for this data transfer request does not match
-	// the one specified in the deal
-	ErrWrongPiece = errors.New("Base CID for deal does not match CID for piece")
-
-	// ErrInacceptableDealState means the deal for this transfer is not in a deal state
-	// where transfer can be performed
-	ErrInacceptableDealState = errors.New("Deal is not a in a state where deals are accepted")
-
-	// AcceptableDealStates are the states in which it would make sense to actually start a data transfer
-	AcceptableDealStates = []api.DealState{api.DealAccepted, api.DealUnknown}
-)
-
-// StorageDataTransferVoucher is the voucher type for data transfers
-// used by the storage market
-type StorageDataTransferVoucher struct {
-	Proposal cid.Cid
-}
-
-// ToBytes converts the StorageDataTransferVoucher to raw bytes
-func (dv StorageDataTransferVoucher) ToBytes() []byte {
-	return dv.Proposal.Bytes()
-}
-
-// FromBytes converts the StorageDataTransferVoucher to raw bytes
-func (dv StorageDataTransferVoucher) FromBytes(raw []byte) (datatransfer.Voucher, error) {
-	c, err := cid.Cast(raw)
-	if err != nil {
-		return nil, err
-	}
-	return StorageDataTransferVoucher{c}, nil
-}
-
-// Identifier is the unique string identifier for a StorageDataTransferVoucher
-func (dv StorageDataTransferVoucher) Identifier() string {
-	return "StorageDataTransferVoucher"
-}
-
-var _ datatransfer.RequestValidator = &ClientRequestValidator{}
-
-// ClientRequestValidator validates data transfer requests for the client
-// in a storage market
-type ClientRequestValidator struct {
-	deals *statestore.StateStore
-}
-
-// RegisterClientValidator is an initialization hook that registers the client
-// request validator with the data transfer module as the validator for
-// StorageDataTransferVoucher types
-func RegisterClientValidator(lc fx.Lifecycle, crv *ClientRequestValidator, dtm datatransfer.ClientDataTransfer) {
-	lc.Append(fx.Hook{
-		OnStart: func(ctx context.Context) error {
-			return dtm.RegisterVoucherType(reflect.TypeOf(StorageDataTransferVoucher{}), crv)
-		},
-	})
-}
-
-// NewClientRequestValidator returns a new client request validator for the
-// given datastore
-func NewClientRequestValidator(ds dtypes.MetadataDS) *ClientRequestValidator {
-	crv := &ClientRequestValidator{
-		deals: statestore.New(namespace.Wrap(ds, datastore.NewKey("/deals/client"))),
-	}
-	return crv
-}
-
-// ValidatePush validates a push request received from the peer that will send data
-// Will always error because clients should not accept push requests from a provider
-// in a storage deal (i.e. send data to client).
-func (c *ClientRequestValidator) ValidatePush(
-	sender peer.ID,
-	voucher datatransfer.Voucher,
-	baseCid cid.Cid,
-	Selector ipld.Node) error {
-	return ErrNoPushAccepted
-}
-
-// ValidatePull validates a pull request received from the peer that will receive data
-// Will succeed only if:
-// - voucher has correct type
-// - voucher references an active deal
-// - referenced deal matches the receiver (miner)
-// - referenced deal matches the given base CID
-// - referenced deal is in an acceptable state
-func (c *ClientRequestValidator) ValidatePull(
-	receiver peer.ID,
-	voucher datatransfer.Voucher,
-	baseCid cid.Cid,
-	Selector ipld.Node) error {
-	dealVoucher, ok := voucher.(StorageDataTransferVoucher)
-	if !ok {
-		return ErrWrongVoucherType
-	}
-
-	var deal ClientDeal
-	err := c.deals.Mutate(dealVoucher.Proposal, func(d *ClientDeal) error {
-		deal = *d
-		return nil
-	})
-	if err != nil {
-		return ErrNoDeal
-	}
-	if deal.Miner != receiver {
-		return ErrWrongPeer
-	}
-	if !bytes.Equal(deal.Proposal.PieceRef, baseCid.Bytes()) {
-		return ErrWrongPiece
-	}
-	for _, state := range AcceptableDealStates {
-		if deal.State == state {
-			return nil
-		}
-	}
-	return ErrInacceptableDealState
-}
-
-var _ datatransfer.RequestValidator = &ProviderRequestValidator{}
-
-// ProviderRequestValidator validates data transfer requests for the provider
-// in a storage market
-type ProviderRequestValidator struct {
-	deals *statestore.StateStore
-}
-
-// RegisterProviderValidator is an initialization hook that registers the provider
-// request validator with the data transfer module as the validator for
-// StorageDataTransferVoucher types
-func RegisterProviderValidator(lc fx.Lifecycle, mrv *ProviderRequestValidator, dtm datatransfer.ProviderDataTransfer) {
-	lc.Append(fx.Hook{
-		OnStart: func(ctx context.Context) error {
-			return dtm.RegisterVoucherType(reflect.TypeOf(StorageDataTransferVoucher{}), mrv)
-		},
-	})
-}
-
-// NewProviderRequestValidator returns a new client request validator for the
-// given datastore
-func NewProviderRequestValidator(ds dtypes.MetadataDS) *ProviderRequestValidator {
-	return &ProviderRequestValidator{
-		deals: statestore.New(namespace.Wrap(ds, datastore.NewKey("/deals/client"))),
-	}
-}
-
-// ValidatePush validates a push request received from the peer that will send data
-// Will succeed only if:
-// - voucher has correct type
-// - voucher references an active deal
-// - referenced deal matches the client
-// - referenced deal matches the given base CID
-// - referenced deal is in an acceptable state
-func (m *ProviderRequestValidator) ValidatePush(
-	sender peer.ID,
-	voucher datatransfer.Voucher,
-	baseCid cid.Cid,
-	Selector ipld.Node) error {
-	dealVoucher, ok := voucher.(StorageDataTransferVoucher)
-	if !ok {
-		return ErrWrongVoucherType
-	}
-
-	var deal MinerDeal
-	err := m.deals.Mutate(dealVoucher.Proposal, func(d *MinerDeal) error {
-		deal = *d
-		return nil
-	})
-	if err != nil {
-		return ErrNoDeal
-	}
-	if deal.Client != sender {
-		return ErrWrongPeer
-	}
-
-	if !bytes.Equal(deal.Proposal.PieceRef, baseCid.Bytes()) {
-		return ErrWrongPiece
-	}
-	for _, state := range AcceptableDealStates {
-		if deal.State == state {
-			return nil
-		}
-	}
-	return ErrInacceptableDealState
-}
-
-// ValidatePull validates a pull request received from the peer that will receive data.
-// Will always error because providers should not accept pull requests from a client
-// in a storage deal (i.e. send data to client).
-func (m *ProviderRequestValidator) ValidatePull(
-	receiver peer.ID,
-	voucher datatransfer.Voucher,
-	baseCid cid.Cid,
-	Selector ipld.Node) error {
-	return ErrNoPullAccepted
-}

chain/deals/request_validation_test.go

@@ -11,13 +11,13 @@ import (
 	dss "github.com/ipfs/go-datastore/sync"
 	blocksutil "github.com/ipfs/go-ipfs-blocksutil"
 	"github.com/libp2p/go-libp2p-core/peer"
+	xerrors "golang.org/x/xerrors"
 
 	"github.com/filecoin-project/lotus/api"
 	"github.com/filecoin-project/lotus/chain/actors"
 	"github.com/filecoin-project/lotus/chain/address"
 	"github.com/filecoin-project/lotus/chain/deals"
 	"github.com/filecoin-project/lotus/chain/types"
-	"github.com/filecoin-project/lotus/datatransfer"
 	"github.com/filecoin-project/lotus/lib/cborrpc"
 	"github.com/filecoin-project/lotus/lib/statestore"
 )
@@ -27,12 +27,12 @@ var blockGenerator = blocksutil.NewBlockGenerator()
 type wrongDTType struct {
 }
 
-func (wrongDTType) ToBytes() []byte {
+func (wrongDTType) ToBytes() ([]byte, error) {
-	return []byte{}
+	return []byte{}, nil
 }
 
-func (wrongDTType) FromBytes([]byte) (datatransfer.Voucher, error) {
+func (wrongDTType) FromBytes([]byte) error {
-	return nil, fmt.Errorf("not implemented")
+	return fmt.Errorf("not implemented")
 }
 
 func (wrongDTType) Identifier() string {
@@ -106,7 +106,7 @@ func TestClientRequestValidation(t *testing.T) {
 	minerId := peer.ID("fakepeerid")
 	block := blockGenerator.Next()
 	t.Run("ValidatePush fails", func(t *testing.T) {
-		if crv.ValidatePush(minerId, wrongDTType{}, block.Cid(), nil) != deals.ErrNoPushAccepted {
+		if !xerrors.Is(crv.ValidatePush(minerId, wrongDTType{}, block.Cid(), nil), deals.ErrNoPushAccepted) {
 			t.Fatal("Push should fail for the client request validator for storage deals")
 		}
 	})
@@ -123,7 +123,7 @@ func TestClientRequestValidation(t *testing.T) {
 		if err != nil {
 			t.Fatal("unable to construct piece cid")
 		}
-		if crv.ValidatePull(minerId, deals.StorageDataTransferVoucher{proposalNd.Cid()}, pieceRef, nil) != deals.ErrNoDeal {
+		if !xerrors.Is(crv.ValidatePull(minerId, &deals.StorageDataTransferVoucher{proposalNd.Cid()}, pieceRef, nil), deals.ErrNoDeal) {
 			t.Fatal("Pull should fail if there is no deal stored")
 		}
 	})
@@ -140,7 +140,7 @@ func TestClientRequestValidation(t *testing.T) {
 		if err != nil {
 			t.Fatal("unable to construct piece cid")
 		}
-		if crv.ValidatePull(minerId, deals.StorageDataTransferVoucher{clientDeal.ProposalCid}, pieceRef, nil) != deals.ErrWrongPeer {
+		if !xerrors.Is(crv.ValidatePull(minerId, &deals.StorageDataTransferVoucher{clientDeal.ProposalCid}, pieceRef, nil), deals.ErrWrongPeer) {
 			t.Fatal("Pull should fail if miner address is incorrect")
 		}
 	})
@@ -152,7 +152,7 @@ func TestClientRequestValidation(t *testing.T) {
 		if err := state.Begin(clientDeal.ProposalCid, &clientDeal); err != nil {
 			t.Fatal("deal tracking failed")
 		}
-		if crv.ValidatePull(minerId, deals.StorageDataTransferVoucher{clientDeal.ProposalCid}, blockGenerator.Next().Cid(), nil) != deals.ErrWrongPiece {
+		if !xerrors.Is(crv.ValidatePull(minerId, &deals.StorageDataTransferVoucher{clientDeal.ProposalCid}, blockGenerator.Next().Cid(), nil), deals.ErrWrongPiece) {
 			t.Fatal("Pull should fail if piece ref is incorrect")
 		}
 	})
@@ -168,7 +168,7 @@ func TestClientRequestValidation(t *testing.T) {
 		if err != nil {
 			t.Fatal("unable to construct piece cid")
 		}
-		if crv.ValidatePull(minerId, deals.StorageDataTransferVoucher{clientDeal.ProposalCid}, pieceRef, nil) != deals.ErrInacceptableDealState {
+		if !xerrors.Is(crv.ValidatePull(minerId, &deals.StorageDataTransferVoucher{clientDeal.ProposalCid}, pieceRef, nil), deals.ErrInacceptableDealState) {
 			t.Fatal("Pull should fail if deal is in a state that cannot be data transferred")
 		}
 	})
@@ -184,7 +184,7 @@ func TestClientRequestValidation(t *testing.T) {
 		if err != nil {
 			t.Fatal("unable to construct piece cid")
 		}
-		if crv.ValidatePull(minerId, deals.StorageDataTransferVoucher{clientDeal.ProposalCid}, pieceRef, nil) != nil {
+		if crv.ValidatePull(minerId, &deals.StorageDataTransferVoucher{clientDeal.ProposalCid}, pieceRef, nil) != nil {
 			t.Fatal("Pull should should succeed when all parameters are correct")
 		}
 	})
@@ -198,7 +198,7 @@ func TestProviderRequestValidation(t *testing.T) {
 	clientID := peer.ID("fakepeerid")
 	block := blockGenerator.Next()
 	t.Run("ValidatePull fails", func(t *testing.T) {
-		if mrv.ValidatePull(clientID, wrongDTType{}, block.Cid(), nil) != deals.ErrNoPullAccepted {
+		if !xerrors.Is(mrv.ValidatePull(clientID, wrongDTType{}, block.Cid(), nil), deals.ErrNoPullAccepted) {
 			t.Fatal("Pull should fail for the provider request validator for storage deals")
 		}
 	})
@@ -216,7 +216,7 @@ func TestProviderRequestValidation(t *testing.T) {
 		if err != nil {
 			t.Fatal("unable to construct piece cid")
 		}
-		if mrv.ValidatePush(clientID, deals.StorageDataTransferVoucher{proposalNd.Cid()}, pieceRef, nil) != deals.ErrNoDeal {
+		if !xerrors.Is(mrv.ValidatePush(clientID, &deals.StorageDataTransferVoucher{proposalNd.Cid()}, pieceRef, nil), deals.ErrNoDeal) {
 			t.Fatal("Push should fail if there is no deal stored")
 		}
 	})
@@ -233,7 +233,7 @@ func TestProviderRequestValidation(t *testing.T) {
 		if err != nil {
 			t.Fatal("unable to construct piece cid")
 		}
-		if mrv.ValidatePush(clientID, deals.StorageDataTransferVoucher{minerDeal.ProposalCid}, pieceRef, nil) != deals.ErrWrongPeer {
+		if !xerrors.Is(mrv.ValidatePush(clientID, &deals.StorageDataTransferVoucher{minerDeal.ProposalCid}, pieceRef, nil), deals.ErrWrongPeer) {
 			t.Fatal("Push should fail if miner address is incorrect")
 		}
 	})
@@ -245,7 +245,7 @@ func TestProviderRequestValidation(t *testing.T) {
 		if err := state.Begin(minerDeal.ProposalCid, &minerDeal); err != nil {
 			t.Fatal("deal tracking failed")
 		}
-		if mrv.ValidatePush(clientID, deals.StorageDataTransferVoucher{minerDeal.ProposalCid}, blockGenerator.Next().Cid(), nil) != deals.ErrWrongPiece {
+		if !xerrors.Is(mrv.ValidatePush(clientID, &deals.StorageDataTransferVoucher{minerDeal.ProposalCid}, blockGenerator.Next().Cid(), nil), deals.ErrWrongPiece) {
 			t.Fatal("Push should fail if piece ref is incorrect")
 		}
 	})
@@ -261,7 +261,7 @@ func TestProviderRequestValidation(t *testing.T) {
 		if err != nil {
 			t.Fatal("unable to construct piece cid")
 		}
-		if mrv.ValidatePush(clientID, deals.StorageDataTransferVoucher{minerDeal.ProposalCid}, pieceRef, nil) != deals.ErrInacceptableDealState {
+		if !xerrors.Is(mrv.ValidatePush(clientID, &deals.StorageDataTransferVoucher{minerDeal.ProposalCid}, pieceRef, nil), deals.ErrInacceptableDealState) {
 			t.Fatal("Push should fail if deal is in a state that cannot be data transferred")
 		}
 	})
@@ -277,7 +277,7 @@ func TestProviderRequestValidation(t *testing.T) {
 		if err != nil {
 			t.Fatal("unable to construct piece cid")
 		}
-		if mrv.ValidatePush(clientID, deals.StorageDataTransferVoucher{minerDeal.ProposalCid}, pieceRef, nil) != nil {
+		if mrv.ValidatePush(clientID, &deals.StorageDataTransferVoucher{minerDeal.ProposalCid}, pieceRef, nil) != nil {
 			t.Fatal("Push should should succeed when all parameters are correct")
 		}
 	})

chain/deals/types.go

@@ -1,6 +1,9 @@
 package deals
 
 import (
+	"bytes"
+	"errors"
+
 	"github.com/filecoin-project/lotus/api"
 	"github.com/filecoin-project/lotus/chain/actors"
 	"github.com/filecoin-project/lotus/chain/address"
@@ -9,6 +12,35 @@ import (
 	"github.com/ipfs/go-cid"
 )
 
+var (
+	// ErrWrongVoucherType means the voucher was not the correct type can validate against
+	ErrWrongVoucherType = errors.New("cannot validate voucher type")
+
+	// ErrNoPushAccepted just means clients do not accept pushes for storage deals
+	ErrNoPushAccepted = errors.New("Client should not receive data for a storage deal")
+
+	// ErrNoPullAccepted just means providers do not accept pulls for storage deals
+	ErrNoPullAccepted = errors.New("Provider should not send data for a storage deal")
+
+	// ErrNoDeal means no active deal was found for this vouchers proposal cid
+	ErrNoDeal = errors.New("No deal found for this proposal")
+
+	// ErrWrongPeer means that the other peer for this data transfer request does not match
+	// the other peer for the deal
+	ErrWrongPeer = errors.New("Data Transfer peer id and Deal peer id do not match")
+
+	// ErrWrongPiece means that the pieceref for this data transfer request does not match
+	// the one specified in the deal
+	ErrWrongPiece = errors.New("Base CID for deal does not match CID for piece")
+
+	// ErrInacceptableDealState means the deal for this transfer is not in a deal state
+	// where transfer can be performed
+	ErrInacceptableDealState = errors.New("Deal is not a in a state where deals are accepted")
+
+	// AcceptableDealStates are the states in which it would make sense to actually start a data transfer
+	AcceptableDealStates = []api.DealState{api.DealAccepted, api.DealUnknown}
+)
+
 const DealProtocolID = "/fil/storage/mk/1.0.1"
 const AskProtocolID = "/fil/storage/ask/1.0.1"
 
@@ -53,3 +85,30 @@ type AskRequest struct {
 type AskResponse struct {
 	Ask *types.SignedStorageAsk
 }
+
+// StorageDataTransferVoucher is the voucher type for data transfers
+// used by the storage market
+type StorageDataTransferVoucher struct {
+	Proposal cid.Cid
+}
+
+// ToBytes converts the StorageDataTransferVoucher to raw bytes
+func (dv *StorageDataTransferVoucher) ToBytes() ([]byte, error) {
+	var buf bytes.Buffer
+	err := dv.MarshalCBOR(&buf)
+	if err != nil {
+		return nil, err
+	}
+	return buf.Bytes(), nil
+}
+
+// FromBytes converts the StorageDataTransferVoucher to raw bytes
+func (dv *StorageDataTransferVoucher) FromBytes(raw []byte) error {
+	r := bytes.NewReader(raw)
+	return dv.UnmarshalCBOR(r)
+}
+
+// Identifier is the unique string identifier for a StorageDataTransferVoucher
+func (dv *StorageDataTransferVoucher) Identifier() string {
+	return "StorageDataTransferVoucher"
+}

datatransfer/dagservice_impl.go

@@ -2,15 +2,14 @@ package datatransfer
 
 import (
 	"context"
-	"fmt"
 	"reflect"
 
 	"github.com/ipfs/go-cid"
 	ipldformat "github.com/ipfs/go-ipld-format"
 	"github.com/ipfs/go-merkledag"
 	ipld "github.com/ipld/go-ipld-prime"
-
 	"github.com/libp2p/go-libp2p-core/peer"
+	"golang.org/x/xerrors"
 
 	"github.com/filecoin-project/lotus/node/modules/dtypes"
 )
@@ -51,15 +50,17 @@ func (impl *dagserviceImpl) RegisterVoucherType(voucherType reflect.Type, valida
 // open a data transfer that will send data to the recipient peer and
 // open a data transfer that will send data to the recipient peer and
 // transfer parts of the piece that match the selector
-func (impl *dagserviceImpl) OpenPushDataChannel(to peer.ID, voucher Voucher, baseCid cid.Cid, Selector ipld.Node) (ChannelID, error) {
+func (impl *dagserviceImpl) OpenPushDataChannel(ctx context.Context, to peer.ID, voucher Voucher, baseCid cid.Cid, Selector ipld.Node) (ChannelID, error) {
-	return ChannelID{}, fmt.Errorf("not implemented")
+	return ChannelID{}, xerrors.Errorf("not implemented")
 }
 
 // open a data transfer that will request data from the sending peer and
 // transfer parts of the piece that match the selector
-func (impl *dagserviceImpl) OpenPullDataChannel(to peer.ID, voucher Voucher, baseCid cid.Cid, Selector ipld.Node) (ChannelID, error) {
+func (impl *dagserviceImpl) OpenPullDataChannel(ctx context.Context, to peer.ID, voucher Voucher, baseCid cid.Cid, Selector ipld.Node) (ChannelID, error) {
+	ctx, cancel := context.WithCancel(ctx)
 	go func() {
-		err := merkledag.FetchGraph(context.TODO(), baseCid, impl.dag)
+		defer cancel()
+		err := merkledag.FetchGraph(ctx, baseCid, impl.dag)
 		var event Event
 		if err != nil {
 			event = Error

datatransfer/types.go

@@ -1,6 +1,7 @@
 package datatransfer
 
 import (
+	"context"
 	"reflect"
 
 	"github.com/ipfs/go-cid"
@@ -14,9 +15,9 @@ import (
 // from bytes, and has a string identifier type
 type Voucher interface {
 	// ToBytes converts the Voucher to raw bytes
-	ToBytes() []byte
+	ToBytes() ([]byte, error)
 	// FromBytes reads a Voucher from raw bytes
-	FromBytes([]byte) (Voucher, error)
+	FromBytes([]byte) error
 	// Identifier is a unique string identifier for this voucher type
 	Identifier() string
 }
@@ -152,11 +153,11 @@ type Manager interface {
 	// open a data transfer that will send data to the recipient peer and
 	// open a data transfer that will send data to the recipient peer and
 	// transfer parts of the piece that match the selector
-	OpenPushDataChannel(to peer.ID, voucher Voucher, baseCid cid.Cid, selector ipld.Node) (ChannelID, error)
+	OpenPushDataChannel(ctx context.Context, to peer.ID, voucher Voucher, baseCid cid.Cid, selector ipld.Node) (ChannelID, error)
 
 	// open a data transfer that will request data from the sending peer and
 	// transfer parts of the piece that match the selector
-	OpenPullDataChannel(to peer.ID, voucher Voucher, baseCid cid.Cid, selector ipld.Node) (ChannelID, error)
+	OpenPullDataChannel(ctx context.Context, to peer.ID, voucher Voucher, baseCid cid.Cid, selector ipld.Node) (ChannelID, error)
 
 	// close an open channel (effectively a cancel)
 	CloseDataTransferChannel(x ChannelID)

gen/main.go

@@ -143,6 +143,7 @@ func main() {
 		deals.ClientDealProposal{},
 		deals.ClientDeal{},
 		deals.MinerDeal{},
+		deals.StorageDataTransferVoucher{},
 	)
 	if err != nil {
 		fmt.Println(err)