feat(bsync): initial work on bsync

actions/manifest.go

@@ -1,56 +1,41 @@
 package actions
 
 import (
-	"context"
-
+	"github.com/qri-io/qri/base"
 	"github.com/qri-io/qri/manifest"
 	"github.com/qri-io/qri/p2p"
 
-	"gx/ipfs/QmPSQnBKM9g7BaUcZCvswUJVscQ1ipjmwxN5PXCjkp9EQ7/go-cid"
 	ipld "gx/ipfs/QmR7TcHkR9nxkUorfi8XMTAMLUK7GiP64TWWBzY3aacc1o/go-ipld-format"
 	"gx/ipfs/QmUJYo4etAQqFfSS2rarFAE97eNGB8ej64YkRT2SmsYD4r/go-ipfs/core/coreapi"
-	coreiface "gx/ipfs/QmUJYo4etAQqFfSS2rarFAE97eNGB8ej64YkRT2SmsYD4r/go-ipfs/core/coreapi/interface"
 )
 
 // NewManifest generates a manifest for a given node
 func NewManifest(node *p2p.QriNode, path string) (*manifest.Manifest, error) {
-	ipfsn, err := node.IPFSNode()
+	ng, err := newNodeGetter(node)
 	if err != nil {
 		return nil, err
 	}
 
-	id, err := cid.Parse(path)
+	return base.NewManifest(node.Context(), ng, path)
+}
+
+// Missing returns a manifest describing blocks that are not in this node for a given manifest
+func Missing(node *p2p.QriNode, m *manifest.Manifest) (missing *manifest.Manifest, err error) {
+	ng, err := newNodeGetter(node)
 	if err != nil {
 		return nil, err
 	}
 
-	ng := &nodeGetter{dag: coreapi.NewCoreAPI(ipfsn).Dag()}
-	return manifest.NewManifest(node.Context(), ng, id)
+	return base.Missing(node.Context(), ng, m)
 }
 
-type nodeGetter struct {
-	dag coreiface.DagAPI
-}
-
-// Get retrieves nodes by CID. Depending on the NodeGetter
-// implementation, this may involve fetching the Node from a remote
-// machine; consider setting a deadline in the context.
-func (ng *nodeGetter) Get(ctx context.Context, id cid.Cid) (ipld.Node, error) {
-	path, err := coreiface.ParsePath(id.String())
+// newNodeGetter generates an ipld.NodeGetter from a QriNode
+func newNodeGetter(node *p2p.QriNode) (ng ipld.NodeGetter, err error) {
+	ipfsn, err := node.IPFSNode()
 	if err != nil {
 		return nil, err
 	}
-	return ng.dag.Get(ctx, path)
-}
 
-// GetMany returns a channel of NodeOptions given a set of CIDs.
-func (ng *nodeGetter) GetMany(ctx context.Context, cids []cid.Cid) <-chan *ipld.NodeOption {
-	ch := make(chan *ipld.NodeOption)
-	go func() {
-		for _, id := range cids {
-			n, err := ng.Get(ctx, id)
-			ch <- &ipld.NodeOption{Err: err, Node: n}
-		}
-	}()
-	return ch
+	ng = &manifest.NodeGetter{Dag: coreapi.NewCoreAPI(ipfsn).Dag()}
+	return
 }

base/manifest.go

@@ -0,0 +1,38 @@
+package base
+
+import (
+	"context"
+
+	"github.com/qri-io/qri/manifest"
+
+	"gx/ipfs/QmPSQnBKM9g7BaUcZCvswUJVscQ1ipjmwxN5PXCjkp9EQ7/go-cid"
+	ipld "gx/ipfs/QmR7TcHkR9nxkUorfi8XMTAMLUK7GiP64TWWBzY3aacc1o/go-ipld-format"
+)
+
+// NewManifest generates a manifest for a given node
+func NewManifest(ctx context.Context, ng ipld.NodeGetter, path string) (*manifest.Manifest, error) {
+	id, err := cid.Parse(path)
+	if err != nil {
+		return nil, err
+	}
+
+	return manifest.NewManifest(ctx, ng, id)
+}
+
+// Missing returns a manifest describing blocks that are not in this node for a given manifest
+func Missing(ctx context.Context, ng ipld.NodeGetter, m *manifest.Manifest) (missing *manifest.Manifest, err error) {
+	var nodes []string
+
+	for _, idstr := range m.Nodes {
+		id, err := cid.Parse(idstr)
+		if err != nil {
+			return nil, err
+		}
+		if _, err := ng.Get(ctx, id); err == ipld.ErrNotFound {
+			nodes = append(nodes, id.String())
+		} else if err != nil {
+			return nil, err
+		}
+	}
+	return &manifest.Manifest{Nodes: nodes}, nil
+}