feat: Add traces for retrievals

pkg/client/accessdelegate_test.go

@@ -231,7 +231,7 @@ func TestAccessDelegate(t *testing.T) {
 						inv invocation.Invocation,
 						context server.InvocationContext,
 					) (result.Result[access.DelegateOk, failure.IPLDBuilderFailure], fx.Effects, error) {
-						return result.Error[access.DelegateOk, failure.IPLDBuilderFailure](
+						return result.Error[access.DelegateOk](
 							failure.FromError(fmt.Errorf("test error")),
 						), nil, nil
 					},

pkg/client/client.go

@@ -10,6 +10,7 @@ import (
 	captypes "github.com/storacha/go-libstoracha/capabilities/types"
 	ucancap "github.com/storacha/go-libstoracha/capabilities/ucan"
 	uclient "github.com/storacha/go-ucanto/client"
+	rclient "github.com/storacha/go-ucanto/client/retrieval"
 	"github.com/storacha/go-ucanto/core/delegation"
 	"github.com/storacha/go-ucanto/core/invocation"
 	"github.com/storacha/go-ucanto/core/receipt"
@@ -34,6 +35,7 @@ import (
 var (
 	log    = logging.Logger("github.com/storacha/guppy/pkg/client")
 	tracer = otel.Tracer("github.com/storacha/guppy/pkg/client")
+	meter  = otel.Meter("github.com/storacha/guppy/pkg/client")
 )
 
 type Client struct {
@@ -42,6 +44,7 @@ type Client struct {
 	data             agentdata.AgentData
 	saveFn           func(agentdata.AgentData) error
 	additionalProofs []delegation.Delegation
+	retrievalOpts    []rclient.Option
 }
 
 // NewClient creates a new client.

pkg/client/dagservice/dagservice.go

@@ -2,30 +2,39 @@ package dagservice
 
 import (
 	"context"
+	"io"
 
 	"github.com/ipfs/boxo/blockservice"
 	"github.com/ipfs/boxo/blockstore"
 	"github.com/ipfs/boxo/ipld/merkledag"
 	ds "github.com/ipfs/go-datastore"
 	dssync "github.com/ipfs/go-datastore/sync"
 	ipldfmt "github.com/ipfs/go-ipld-format"
-	rclient "github.com/storacha/go-ucanto/client/retrieval"
+	logging "github.com/ipfs/go-log/v2"
 	"github.com/storacha/go-ucanto/did"
 	"github.com/storacha/guppy/pkg/client"
 	"github.com/storacha/guppy/pkg/client/locator"
+	"go.opentelemetry.io/otel"
 )
 
+var (
+	log    = logging.Logger("client/dagservice")
+	tracer = otel.Tracer("client/dagservice")
+)
+
+// Retriever can fetch content from a given [locator.Location]. `Retrieve` does
+// no data validation.
 type Retriever interface {
-	Retrieve(ctx context.Context, space did.DID, location locator.Location, retrievalOpts ...rclient.Option) ([]byte, error)
+	Retrieve(ctx context.Context, location locator.Location) (io.ReadCloser, error)
 }
 
 var _ Retriever = (*client.Client)(nil)
 
-func NewDAGService(locator locator.Locator, retriever Retriever, space did.DID) ipldfmt.DAGService {
+func NewDAGService(locator locator.Locator, retriever Retriever, space did.DID, opts ...ExchangeOption) ipldfmt.DAGService {
 	return merkledag.NewReadOnlyDagService(
 		merkledag.NewDAGService(blockservice.New(
 			blockstore.NewBlockstore(dssync.MutexWrap(ds.NewMapDatastore())),
-			NewExchange(locator, retriever, space),
+			NewExchange(locator, retriever, space, opts...),
 		)),
 	)
 }