Receipt writing

client/connection.go

@@ -80,7 +80,7 @@ type ExecutionResponse interface {
 }
 
 func Execute(invocations []invocation.Invocation, conn Connection) (ExecutionResponse, error) {
-	input, err := message.Build(invocations)
+	input, err := message.Build(invocations, nil)
 	if err != nil {
 		return nil, fmt.Errorf("building message: %s", err)
 	}

core/dag/blockstore/blockstore.go

@@ -194,3 +194,21 @@ func NewBlockReader(options ...Option) (BlockReader, error) {
 
 	return &blockreader{keys, blks}, nil
 }
+
+func Encode(view ipld.View, bs BlockWriter) error {
+	blks := view.Blocks()
+	for {
+		b, err := blks.Next()
+		if err != nil {
+			if err == io.EOF {
+				break
+			}
+			return fmt.Errorf("reading proof blocks: %s", err)
+		}
+		err = bs.Put(b)
+		if err != nil {
+			return fmt.Errorf("putting proof block: %s", err)
+		}
+	}
+	return nil
+}

core/delegation/delegate.go

@@ -2,7 +2,6 @@ package delegation
 
 import (
 	"fmt"
-	"io"
 
 	"github.com/web3-storage/go-ucanto/core/dag/blockstore"
 	"github.com/web3-storage/go-ucanto/core/ipld/block"
@@ -20,7 +19,7 @@ type delegationConfig struct {
 	nbf uint64
 	nnc string
 	fct []ucan.FactBuilder
-	prf []Delegation
+	prf Proofs
 }
 
 // WithExpiration configures the expiration time in UTC seconds since Unix
@@ -61,7 +60,7 @@ func WithFacts(fct []ucan.FactBuilder) Option {
 // `Delegation` is not the resource owner / service provider, for the delegated
 // capabilities, the `proofs` must contain valid `Proof`s containing
 // delegations to the `issuer`.
-func WithProofs(prf []Delegation) Option {
+func WithProofs(prf Proofs) Option {
 	return func(cfg *delegationConfig) error {
 		cfg.prf = prf
 		return nil
@@ -79,28 +78,14 @@ func Delegate(issuer ucan.Signer, audience ucan.Principal, capabilities []ucan.C
 		}
 	}
 
-	var links []ucan.Link
 	bs, err := blockstore.NewBlockStore()
 	if err != nil {
 		return nil, err
 	}
 
-	for _, p := range cfg.prf {
-		links = append(links, p.Link())
-		blks := p.Blocks()
-		for {
-			b, err := blks.Next()
-			if err != nil {
-				if err == io.EOF {
-					break
-				}
-				return nil, fmt.Errorf("reading proof blocks: %s", err)
-			}
-			err = bs.Put(b)
-			if err != nil {
-				return nil, fmt.Errorf("putting proof block: %s", err)
-			}
-		}
+	links, err := cfg.prf.Encode(bs)
+	if err != nil {
+		return nil, err
 	}
 
 	data, err := ucan.Issue(

core/delegation/delegation.go

@@ -22,7 +22,7 @@ import (
 // Delagation is a materialized view of a UCAN delegation, which can be encoded
 // into a UCAN token and used as proof for an invocation or further delegations.
 type Delegation interface {
-	ipld.IPLDView
+	ipld.View
 	// Link returns the IPLD link of the root block of the delegation.
 	Link() ucan.Link
 	// Archive writes the delegation to a Content Addressed aRchive (CAR).

core/delegation/proofs.go

@@ -0,0 +1,60 @@
+package delegation
+
+import (
+	"github.com/web3-storage/go-ucanto/core/dag/blockstore"
+	"github.com/web3-storage/go-ucanto/core/ipld"
+	"github.com/web3-storage/go-ucanto/ucan"
+)
+
+type Proof struct {
+	delegation Delegation
+	link       ucan.Link
+}
+
+func (p Proof) Delegation() (Delegation, bool) {
+	return p.delegation, p.delegation != nil
+}
+
+func (p Proof) Link() ucan.Link {
+	if p.delegation != nil {
+		return p.delegation.Link()
+	}
+	return p.link
+}
+
+func FromDelegation(delegation Delegation) Proof {
+	return Proof{delegation, nil}
+}
+
+func FromLink(link ucan.Link) Proof {
+	return Proof{nil, link}
+}
+
+type Proofs []Proof
+
+func NewProofsView(links []ipld.Link, bs blockstore.BlockReader) Proofs {
+	proofs := make(Proofs, 0, len(links))
+	for _, link := range links {
+		if delegation, err := NewDelegationView(link, bs); err == nil {
+			proofs = append(proofs, FromDelegation(delegation))
+		} else {
+			proofs = append(proofs, FromLink(link))
+		}
+	}
+	return proofs
+}
+
+// Encode writes a set of proofs, some of which may be full delegations to a blockstore
+func (proofs Proofs) Encode(bs blockstore.BlockWriter) ([]ipld.Link, error) {
+	links := make([]ucan.Link, 0, len(proofs))
+	for _, p := range proofs {
+		links = append(links, p.Link())
+		if delegation, isDelegation := p.Delegation(); isDelegation {
+			err := blockstore.Encode(delegation, bs)
+			if err != nil {
+				return nil, err
+			}
+		}
+	}
+	return links, nil
+}

core/invocation/invocation.go

@@ -35,3 +35,34 @@ type IssuedInvocation interface {
 func Invoke(issuer ucan.Signer, audience ucan.Principal, capability ucan.Capability[ucan.CaveatBuilder], options ...delegation.Option) (IssuedInvocation, error) {
 	return delegation.Delegate(issuer, audience, []ucan.Capability[ucan.CaveatBuilder]{capability}, options...)
 }
+
+type Ran struct {
+	invocation Invocation
+	link       ucan.Link
+}
+
+func (r Ran) Invocation() (Invocation, bool) {
+	return r.invocation, r.invocation != nil
+}
+
+func (r Ran) Link() ucan.Link {
+	if r.invocation != nil {
+		return r.invocation.Link()
+	}
+	return r.link
+}
+
+func FromInvocation(invocation Invocation) Ran {
+	return Ran{invocation, nil}
+}
+
+func FromLink(link ucan.Link) Ran {
+	return Ran{nil, link}
+}
+
+func (r Ran) Encode(bs blockstore.BlockWriter) (ipld.Link, error) {
+	if invocation, ok := r.Invocation(); ok {
+		return r.Link(), blockstore.Encode(invocation, bs)
+	}
+	return r.Link(), nil
+}

core/ipld/lib.go

@@ -7,3 +7,4 @@ import (
 
 type Link = ipld.Link
 type Block = block.Block
+type Node = ipld.Node

core/ipld/view.go

@@ -7,7 +7,7 @@ import (
 // View represents a materialized IPLD DAG View, which provides a generic
 // traversal API. It is useful for encoding (potentially partial) IPLD DAGs
 // into content archives (e.g. CARs).
-type IPLDView interface {
+type View interface {
 	// Root is the root block of the IPLD DAG this is the view of. This is the
 	// block from which all other blocks are linked directly or transitively.
 	Root() Block
@@ -21,3 +21,14 @@ type IPLDView interface {
 	// omitting it when encoding the view into a CAR archive.
 	Blocks() iterable.Iterator[Block]
 }
+
+// ViewBuilder represents a materializable IPLD DAG View. It is a useful
+// abstraction that can be used to defer actual IPLD encoding.
+//
+// Note that represented DAG could be partial implying that some of the blocks
+// may not be included. This by design allowing a user to include whatever
+// blocks they want to include.
+type ViewBuilder[V View] interface {
+	// BuildIPLDView encodes all the blocks and creates a new IPLDView instance over them.
+	BuildIPLDView() V
+}

core/message/message.go

@@ -2,7 +2,6 @@ package message
 
 import (
 	"fmt"
-	"io"
 
 	"github.com/web3-storage/go-ucanto/core/dag/blockstore"
 	"github.com/web3-storage/go-ucanto/core/invocation"
@@ -12,10 +11,11 @@ import (
 	"github.com/web3-storage/go-ucanto/core/ipld/hash/sha256"
 	"github.com/web3-storage/go-ucanto/core/iterable"
 	mdm "github.com/web3-storage/go-ucanto/core/message/datamodel"
+	"github.com/web3-storage/go-ucanto/core/receipt"
 )
 
 type AgentMessage interface {
-	ipld.IPLDView
+	ipld.View
 	// Invocations is a list of links to the root block of invocations than can
 	// be found in the message.
 	Invocations() []ipld.Link
@@ -73,7 +73,7 @@ func (m *message) Get(link ipld.Link) (ipld.Link, bool) {
 	return rcpt, true
 }
 
-func Build(invocations []invocation.Invocation) (AgentMessage, error) {
+func Build(invocations []invocation.Invocation, receipts []receipt.UniversalReceipt) (AgentMessage, error) {
 	bs, err := blockstore.NewBlockStore()
 	if err != nil {
 		return nil, err
@@ -83,25 +83,35 @@ func Build(invocations []invocation.Invocation) (AgentMessage, error) {
 	for _, inv := range invocations {
 		ex = append(ex, inv.Link())
 
-		blks := inv.Blocks()
-		for {
-			b, err := blks.Next()
+		err := blockstore.Encode(inv, bs)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	var report *mdm.ReportModel
+	if len(receipts) > 0 {
+		report = &mdm.ReportModel{
+			Keys:   make([]string, 0, len(receipts)),
+			Values: make(map[string]ipld.Link, len(receipts)),
+		}
+		for _, receipt := range receipts {
+			err := blockstore.Encode(receipt, bs)
 			if err != nil {
-				if err == io.EOF {
-					break
-				}
-				return nil, fmt.Errorf("reading invocation blocks: %s", err)
+				return nil, err
 			}
-			err = bs.Put(b)
-			if err != nil {
-				return nil, fmt.Errorf("putting invocation block: %s", err)
+
+			key := receipt.Ran().Link().String()
+			if _, ok := report.Values[key]; !ok {
+				report.Values[key] = receipt.Root().Link()
 			}
 		}
 	}
 
 	msg := mdm.AgentMessageModel{
 		UcantoMessage7: &mdm.DataModel{
 			Execute: ex,
+			Report:  report,
 		},
 	}
 

core/receipt/datamodel/receipt.go

@@ -37,8 +37,8 @@ type MetaModel struct {
 }
 
 type ResultModel[O any, X any] struct {
-	Ok  O
-	Err X
+	Ok  *O
+	Err *X
 }
 
 // NewReceiptModelType creates a new schema.Type for a Receipt. You must

core/receipt/datamodel/receipt_test.go

@@ -39,10 +39,10 @@ func TestEncodeDecode(t *testing.T) {
 	}
 
 	l := cidlink.Link{Cid: cid.MustParse("bafkreiem4twkqzsq2aj4shbycd4yvoj2cx72vezicletlhi7dijjciqpui")}
-	r0 := rdm.ReceiptModel[*resultOk, *resultErr]{
-		Ocm: rdm.OutcomeModel[*resultOk, *resultErr]{
+	r0 := rdm.ReceiptModel[resultOk, resultErr]{
+		Ocm: rdm.OutcomeModel[resultOk, resultErr]{
 			Ran: l,
-			Out: rdm.ResultModel[*resultOk, *resultErr]{
+			Out: rdm.ResultModel[resultOk, resultErr]{
 				Ok: &resultOk{Status: "done"},
 			},
 		},
@@ -51,7 +51,7 @@ func TestEncodeDecode(t *testing.T) {
 	if err != nil {
 		t.Fatalf("encoding receipt: %s", err)
 	}
-	r1 := rdm.ReceiptModel[*resultOk, *resultErr]{}
+	r1 := rdm.ReceiptModel[resultOk, resultErr]{}
 	err = block.Decode(b0, &r1, typ, cbor.Codec, sha256.Hasher)
 	if err != nil {
 		t.Fatalf("decoding receipt: %s", err)
@@ -63,10 +63,10 @@ func TestEncodeDecode(t *testing.T) {
 		t.Fatalf("status was not done")
 	}
 
-	r2 := rdm.ReceiptModel[*resultOk, *resultErr]{
-		Ocm: rdm.OutcomeModel[*resultOk, *resultErr]{
+	r2 := rdm.ReceiptModel[resultOk, resultErr]{
+		Ocm: rdm.OutcomeModel[resultOk, resultErr]{
 			Ran: l,
-			Out: rdm.ResultModel[*resultOk, *resultErr]{
+			Out: rdm.ResultModel[resultOk, resultErr]{
 				Err: &resultErr{Message: "boom"},
 			},
 		},
@@ -75,7 +75,7 @@ func TestEncodeDecode(t *testing.T) {
 	if err != nil {
 		t.Fatalf("encoding receipt: %s", err)
 	}
-	r3 := rdm.ReceiptModel[*resultOk, *resultErr]{}
+	r3 := rdm.ReceiptModel[resultOk, resultErr]{}
 	err = block.Decode(b1, &r3, typ, cbor.Codec, sha256.Hasher)
 	if err != nil {
 		t.Fatalf("decoding receipt: %s", err)