coreapi: path remainders

License: MIT
Signed-off-by: Łukasz Magiera <magik6k@gmail.com>

core/coreapi/interface/path.go

@@ -29,13 +29,14 @@ type Path interface {
 
 // ResolvedPath is a resolved Path
 type ResolvedPath interface {
-	// Cid returns cid referred to by path
+	// Cid returns the CID referred to by path
 	Cid() *cid.Cid
 
-	// Root returns cid of root path
+	// Root returns the CID of root path
 	Root() *cid.Cid
 
-	//TODO: Path remainder
+	// Remainder returns unresolved part of the path
+	Remainder() string
 
 	Path
 }

core/coreapi/path.go

 package coreapi
 
 import (
-	"context"
+	context "context"
+	gopath "path"
+	strings "strings"
 
 	core "github.com/ipfs/go-ipfs/core"
 	coreiface "github.com/ipfs/go-ipfs/core/coreapi/interface"
@@ -22,18 +24,29 @@ type path struct {
 // resolvedPath implements coreiface.resolvedPath
 type resolvedPath struct {
 	path
-	cid  *cid.Cid
-	root *cid.Cid
+	cid       *cid.Cid
+	root      *cid.Cid
+	remainder string
 }
 
 // IpfsPath parses the path from `c`, reruns the parsed path.
 func (api *CoreAPI) IpfsPath(c *cid.Cid) coreiface.ResolvedPath {
-	return &resolvedPath{path: path{ipfspath.Path("/ipfs/" + c.String())}, cid: c, root: c}
+	return &resolvedPath{
+		path:      path{ipfspath.Path("/ipfs/" + c.String())},
+		cid:       c,
+		root:      c,
+		remainder: "",
+	}
 }
 
 // IpldPath parses the path from `c`, reruns the parsed path.
 func (api *CoreAPI) IpldPath(c *cid.Cid) coreiface.ResolvedPath {
-	return &resolvedPath{path: path{ipfspath.Path("/ipld/" + c.String())}, cid: c, root: c}
+	return &resolvedPath{
+		path:      path{ipfspath.Path("/ipld/" + c.String())},
+		cid:       c,
+		root:      c,
+		remainder: "",
+	}
 }
 
 // ResolveNode resolves the path `p` using Unixfs resolver, gets and returns the
@@ -66,25 +79,40 @@ func resolvePath(ctx context.Context, ng ipld.NodeGetter, nsys namesys.NameSyste
 		return p.(coreiface.ResolvedPath), nil
 	}
 
+	ipath := p.(*path).path
+	ipath, err := core.ResolveIPNS(ctx, nsys, ipath)
+	if err == core.ErrNoNamesys {
+		return nil, coreiface.ErrOffline
+	} else if err != nil {
+		return nil, err
+	}
+
+	resolveOnce := uio.ResolveUnixfsOnce
+	if strings.HasPrefix(ipath.String(), "/ipld") {
+		resolveOnce = resolver.ResolveSingle
+	}
+
 	r := &resolver.Resolver{
 		DAG:         ng,
-		ResolveOnce: uio.ResolveUnixfsOnce,
+		ResolveOnce: resolveOnce,
 	}
 
-	p2 := ipfspath.FromString(p.String())
-	node, err := core.Resolve(ctx, nsys, r, p2)
-	if err == core.ErrNoNamesys {
-		return nil, coreiface.ErrOffline
-	} else if err != nil {
+	node, rest, err := r.ResolveToLastNode(ctx, ipath)
+	if err != nil {
 		return nil, err
 	}
 
 	var root *cid.Cid
-	if p2.IsJustAKey() {
+	if ipath.IsJustAKey() {
 		root = node.Cid()
 	}
 
-	return &resolvedPath{path: path{p2}, cid: node.Cid(), root: root}, nil
+	return &resolvedPath{
+		path:      path{ipath},
+		cid:       node.Cid(),
+		root:      root,
+		remainder: gopath.Join(rest...),
+	}, nil
 }
 
 // ParsePath parses path `p` using ipfspath parser, returns the parsed path.
@@ -120,3 +148,7 @@ func (p *resolvedPath) Cid() *cid.Cid {
 func (p *resolvedPath) Root() *cid.Cid {
 	return p.root
 }
+
+func (p *resolvedPath) Remainder() string {
+	return p.remainder
+}

core/coreapi/path_test.go

@@ -32,3 +32,84 @@ func TestMutablePath(t *testing.T) {
 		t.Error("expected /ipld path to be immutable")
 	}
 }
+
+func TestPathRemainder(t *testing.T) {
+	ctx := context.Background()
+	_, api, err := makeAPI(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	obj, err := api.Dag().Put(ctx, strings.NewReader(`{"foo": {"bar": "baz"}}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	p1, err := api.ParsePath(obj.String() + "/foo/bar")
+	if err != nil {
+		t.Error(err)
+	}
+
+	rp1, err := api.ResolvePath(ctx, p1)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if rp1.Remainder() != "foo/bar" {
+		t.Error("expected to get path remainder")
+	}
+}
+
+func TestEmptyPathRemainder(t *testing.T) {
+	ctx := context.Background()
+	_, api, err := makeAPI(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	obj, err := api.Dag().Put(ctx, strings.NewReader(`{"foo": {"bar": "baz"}}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if obj.Remainder() != "" {
+		t.Error("expected the resolved path to not have a remainder")
+	}
+
+	p1, err := api.ParsePath(obj.String())
+	if err != nil {
+		t.Error(err)
+	}
+
+	rp1, err := api.ResolvePath(ctx, p1)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if rp1.Remainder() != "" {
+		t.Error("expected the resolved path to not have a remainder")
+	}
+}
+
+func TestInvalidPathRemainder(t *testing.T) {
+	ctx := context.Background()
+	_, api, err := makeAPI(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	obj, err := api.Dag().Put(ctx, strings.NewReader(`{"foo": {"bar": "baz"}}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	p1, err := api.ParsePath(obj.String() + "/bar/baz")
+	if err != nil {
+		t.Error(err)
+	}
+
+	_, err = api.ResolvePath(ctx, p1)
+	if err == nil || err.Error() != "no such link found" {
+		t.Fatalf("unexpected error: %s", err)
+	}
+}

core/pathresolver.go

@@ -19,10 +19,8 @@ import (
 var ErrNoNamesys = errors.New(
 	"core/resolve: no Namesys on IpfsNode - can't resolve ipns entry")
 
-// Resolve resolves the given path by parsing out protocol-specific
-// entries (e.g. /ipns/<node-key>) and then going through the /ipfs/
-// entries and returning the final node.
-func Resolve(ctx context.Context, nsys namesys.NameSystem, r *resolver.Resolver, p path.Path) (ipld.Node, error) {
+// ResolveIPNS resolves /ipns paths
+func ResolveIPNS(ctx context.Context, nsys namesys.NameSystem, p path.Path) (path.Path, error) {
 	if strings.HasPrefix(p.String(), "/ipns/") {
 		evt := log.EventBegin(ctx, "resolveIpnsPath")
 		defer evt.Done()
@@ -31,36 +29,47 @@ func Resolve(ctx context.Context, nsys namesys.NameSystem, r *resolver.Resolver,
 		// TODO(cryptix): we should be able to query the local cache for the path
 		if nsys == nil {
 			evt.Append(logging.LoggableMap{"error": ErrNoNamesys.Error()})
-			return nil, ErrNoNamesys
+			return "", ErrNoNamesys
 		}
 
 		seg := p.Segments()
 
 		if len(seg) < 2 || seg[1] == "" { // just "/<protocol/>" without further segments
 			evt.Append(logging.LoggableMap{"error": path.ErrNoComponents.Error()})
-			return nil, path.ErrNoComponents
+			return "", path.ErrNoComponents
 		}
 
 		extensions := seg[2:]
 		resolvable, err := path.FromSegments("/", seg[0], seg[1])
 		if err != nil {
 			evt.Append(logging.LoggableMap{"error": err.Error()})
-			return nil, err
+			return "", err
 		}
 
 		respath, err := nsys.Resolve(ctx, resolvable.String())
 		if err != nil {
 			evt.Append(logging.LoggableMap{"error": err.Error()})
-			return nil, err
+			return "", err
 		}
 
 		segments := append(respath.Segments(), extensions...)
 		p, err = path.FromSegments("/", segments...)
 		if err != nil {
 			evt.Append(logging.LoggableMap{"error": err.Error()})
-			return nil, err
+			return "", err
 		}
 	}
+	return p, nil
+}
+
+// Resolve resolves the given path by parsing out protocol-specific
+// entries (e.g. /ipns/<node-key>) and then going through the /ipfs/
+// entries and returning the final node.
+func Resolve(ctx context.Context, nsys namesys.NameSystem, r *resolver.Resolver, p path.Path) (ipld.Node, error) {
+	p, err := ResolveIPNS(ctx, nsys, p)
+	if err != nil {
+		return nil, err
+	}
 
 	// ok, we have an IPFS path now (or what we'll treat as one)
 	return r.ResolvePath(ctx, p)

path/path.go

@@ -161,7 +161,7 @@ func SplitList(pth string) []string {
 // must be a Multihash) and return it separately.
 func SplitAbsPath(fpath Path) (*cid.Cid, []string, error) {
 	parts := fpath.Segments()
-	if parts[0] == "ipfs" {
+	if parts[0] == "ipfs" || parts[0] == "ipld" {
 		parts = parts[1:]
 	}