[RFC] MFS interface draft

coreapi.go

@@ -33,6 +33,8 @@ type CoreAPI interface {
 	// ObjectAPI returns an implementation of Object API
 	Object() ObjectAPI
 
+	Files() MfsAPI
+
 	// Dht returns an implementation of Dht API
 	Dht() DhtAPI
 

mfs.go

@@ -0,0 +1,84 @@
+package iface
+
+import (
+	"context"
+	"io"
+	"os"
+	"strings"
+)
+
+// MfsPath
+//
+// Note that Path and ResolvedPath interfaces satisfy this interface
+//
+// This interface is inspired by https://godoc.org/github.com/src-d/go-billy,
+// but doesn't implement it
+type MfsPath interface {
+	// String returns the path as a string.
+	String() string
+
+	// Mutable returns false if the data pointed to by this path in guaranteed
+	// to not change.
+	//
+	// Note that resolved mutable path can be immutable.
+	Mutable() bool
+}
+
+type filesPath struct {
+	p string
+}
+
+func (p *filesPath) String() string {
+	return p.p
+}
+
+func (p *filesPath) Mutable() bool {
+	return !(strings.HasPrefix(p.p, "/ipfs") || strings.HasPrefix(p.p, "/ipld"))
+}
+
+func FilePath(p string) MfsPath {
+	// TODO: more validation
+	return &filesPath{
+		p: p,
+	}
+}
+
+type MfsAPI interface {
+	Create(ctx context.Context, path MfsPath) (File, error)
+	Open(ctx context.Context, path MfsPath) (File, error)
+	OpenFile(ctx context.Context, path MfsPath, flag int, perm os.FileMode) (File, error)
+
+	Stat(ctx context.Context, path MfsPath) (os.FileInfo, error)
+
+	Rename(ctx context.Context, oldpath, newpath MfsPath) error
+	Remove(ctx context.Context, path MfsPath) error
+
+	// ReadDir reads the directory named by dirname and returns a list of
+	// directory entries sorted by filename.
+	ReadDir(ctx context.Context, path MfsPath) ([]os.FileInfo, error)
+	// MkdirAll creates a directory named path, along with any necessary
+	// parents, and returns nil, or else returns an error. The permission bits
+	// perm are used for all directories that MkdirAll creates. If path is
+	// already a directory, MkdirAll does nothing and returns nil.
+	MkdirAll(ctx context.Context, path MfsPath, perm os.FileMode) error
+
+	Flush(ctx context.Context, path MfsPath) error
+	// TODO: ChCid
+	// TODO: Symlink stuff (is it implemented in mfs?)
+}
+
+type File interface {
+	io.Writer
+	io.WriterAt
+	io.Reader
+	io.Seeker
+	io.Closer
+
+	Name() MfsPath
+
+	// Truncate the file.
+	Truncate(size int64) error
+}
+
+var _ MfsPath = (Path)(nil)
+var _ MfsPath = (ResolvedPath)(nil)

tests/api.go

@@ -64,6 +64,7 @@ func TestApi(p Provider) func(t *testing.T) {
 		t.Run("Key", tp.TestKey)
 		t.Run("Name", tp.TestName)
 		t.Run("Object", tp.TestObject)
+		t.Run("Mfs", tp.TestMfs)
 		t.Run("Path", tp.TestPath)
 		t.Run("Pin", tp.TestPin)
 		t.Run("PubSub", tp.TestPubSub)

tests/mfs.go

@@ -0,0 +1,27 @@
+package tests
+
+import (
+	"context"
+	"testing"
+
+	"github.com/ipfs/interface-go-ipfs-core"
+)
+
+func (tp *provider) TestMfs(t *testing.T) {
+	t.Run("TestFilesDirs", tp.TestFilesDirs)
+}
+
+func (tp *provider) TestFilesDirs(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	api, err := tp.makeAPI(ctx)
+	if err != nil {
+		t.Fatal(err)
+		return
+	}
+
+	l, err := api.Files().ReadDir(ctx, iface.FilePath("/test"))
+	if len(l) != 0 {
+		return
+	}
+}