feat(filecoin): PDP link on filecoin/offer caveats (#69)

add an optional PDP link on filecoin/offer caveats

---------

Co-authored-by: Petra Jaros <[email protected]>

Author: hannahhoward

capabilities/filecoin/filecoin.ipldsch

@@ -1,6 +1,7 @@
 type OfferCaveats struct {
     content Link
     piece Link
+    PDP optional V1Link
 }
 
 type OfferOk struct {

capabilities/filecoin/offer.go

@@ -15,6 +15,9 @@ const OfferAbility = "filecoin/offer"
 type OfferCaveats struct {
 	Content ipld.Link
 	Piece   ipld.Link
+
+	// Link to `pdp/accept` capability, if applicable
+	PDP *ipld.Link
 }
 
 func (oc OfferCaveats) ToIPLD() (datamodel.Node, error) {

capabilities/filecoin/offer_test.go

@@ -9,18 +9,38 @@ import (
 )
 
 func TestOfferCaveatsRoundTrip(t *testing.T) {
-	nb := filecoin.OfferCaveats{
-		Content: testutil.RandomCID(t),
-		Piece:   testutil.RandomCID(t),
-	}
-
-	node, err := nb.ToIPLD()
-	require.NoError(t, err)
-
-	rnb, err := filecoin.OfferCaveatsReader.Read(node)
-	require.NoError(t, err)
-	require.Equal(t, nb.Content.String(), rnb.Content.String())
-	require.Equal(t, nb.Piece.String(), rnb.Piece.String())
+	t.Run("no pdp", func(t *testing.T) {
+		nb := filecoin.OfferCaveats{
+			Content: testutil.RandomCID(t),
+			Piece:   testutil.RandomCID(t),
+		}
+
+		node, err := nb.ToIPLD()
+		require.NoError(t, err)
+
+		rnb, err := filecoin.OfferCaveatsReader.Read(node)
+		require.NoError(t, err)
+		require.Equal(t, nb.Content.String(), rnb.Content.String())
+		require.Equal(t, nb.Piece.String(), rnb.Piece.String())
+	})
+	t.Run("with pdp", func(t *testing.T) {
+		pdpLink := testutil.RandomCID(t)
+		nb := filecoin.OfferCaveats{
+			Content: testutil.RandomCID(t),
+			Piece:   testutil.RandomCID(t),
+			PDP:     &pdpLink,
+		}
+
+		node, err := nb.ToIPLD()
+		require.NoError(t, err)
+
+		rnb, err := filecoin.OfferCaveatsReader.Read(node)
+		require.NoError(t, err)
+		require.Equal(t, nb.Content.String(), rnb.Content.String())
+		require.Equal(t, nb.Piece.String(), rnb.Piece.String())
+		require.NotNil(t, rnb.PDP)
+		require.Equal(t, (*nb.PDP).String(), (*rnb.PDP).String())
+	})
 }
 
 func TestOfferOkRoundTrip(t *testing.T) {