Add rootfs service

Add rootfs service to allow creation of rootfs from layer array

Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)

api/services/rootfs/rootfs.pb.go

@@ -0,0 +1,577 @@
+// Code generated by protoc-gen-gogo.
+// source: github.com/docker/containerd/api/services/rootfs/rootfs.proto
+// DO NOT EDIT!
+
+/*
+	Package rootfs is a generated protocol buffer package.
+
+	It is generated from these files:
+		github.com/docker/containerd/api/services/rootfs/rootfs.proto
+
+	It has these top-level messages:
+		PrepareRequest
+		PrepareResponse
+*/
+package rootfs
+
+import proto "github.com/gogo/protobuf/proto"
+import fmt "fmt"
+import math "math"
+import _ "github.com/gogo/protobuf/gogoproto"
+import _ "github.com/golang/protobuf/ptypes/empty"
+import _ "github.com/docker/containerd/api/types/mount"
+import containerd_v1_types1 "github.com/docker/containerd/api/types/descriptor"
+
+import github_com_opencontainers_go_digest "github.com/opencontainers/go-digest"
+
+import (
+	context "golang.org/x/net/context"
+	grpc "google.golang.org/grpc"
+)
+
+import strings "strings"
+import reflect "reflect"
+
+import io "io"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.GoGoProtoPackageIsVersion2 // please upgrade the proto package
+
+type PrepareRequest struct {
+	Layers []*containerd_v1_types1.Descriptor `protobuf:"bytes,1,rep,name=layers" json:"layers,omitempty"`
+}
+
+func (m *PrepareRequest) Reset()                    { *m = PrepareRequest{} }
+func (*PrepareRequest) ProtoMessage()               {}
+func (*PrepareRequest) Descriptor() ([]byte, []int) { return fileDescriptorRootfs, []int{0} }
+
+type PrepareResponse struct {
+	ChainID github_com_opencontainers_go_digest.Digest `protobuf:"bytes,1,opt,name=chainid,proto3,customtype=github.com/opencontainers/go-digest.Digest" json:"chainid"`
+}
+
+func (m *PrepareResponse) Reset()                    { *m = PrepareResponse{} }
+func (*PrepareResponse) ProtoMessage()               {}
+func (*PrepareResponse) Descriptor() ([]byte, []int) { return fileDescriptorRootfs, []int{1} }
+
+func init() {
+	proto.RegisterType((*PrepareRequest)(nil), "containerd.v1.PrepareRequest")
+	proto.RegisterType((*PrepareResponse)(nil), "containerd.v1.PrepareResponse")
+}
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ context.Context
+var _ grpc.ClientConn
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the grpc package it is being compiled against.
+const _ = grpc.SupportPackageIsVersion4
+
+// Client API for RootFS service
+
+type RootFSClient interface {
+	Prepare(ctx context.Context, in *PrepareRequest, opts ...grpc.CallOption) (*PrepareResponse, error)
+}
+
+type rootFSClient struct {
+	cc *grpc.ClientConn
+}
+
+func NewRootFSClient(cc *grpc.ClientConn) RootFSClient {
+	return &rootFSClient{cc}
+}
+
+func (c *rootFSClient) Prepare(ctx context.Context, in *PrepareRequest, opts ...grpc.CallOption) (*PrepareResponse, error) {
+	out := new(PrepareResponse)
+	err := grpc.Invoke(ctx, "/containerd.v1.RootFS/Prepare", in, out, c.cc, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
+// Server API for RootFS service
+
+type RootFSServer interface {
+	Prepare(context.Context, *PrepareRequest) (*PrepareResponse, error)
+}
+
+func RegisterRootFSServer(s *grpc.Server, srv RootFSServer) {
+	s.RegisterService(&_RootFS_serviceDesc, srv)
+}
+
+func _RootFS_Prepare_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(PrepareRequest)
+	if err := dec(in); err != nil {
+		return nil, err
+	}
+	if interceptor == nil {
+		return srv.(RootFSServer).Prepare(ctx, in)
+	}
+	info := &grpc.UnaryServerInfo{
+		Server:     srv,
+		FullMethod: "/containerd.v1.RootFS/Prepare",
+	}
+	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
+		return srv.(RootFSServer).Prepare(ctx, req.(*PrepareRequest))
+	}
+	return interceptor(ctx, in, info, handler)
+}
+
+var _RootFS_serviceDesc = grpc.ServiceDesc{
+	ServiceName: "containerd.v1.RootFS",
+	HandlerType: (*RootFSServer)(nil),
+	Methods: []grpc.MethodDesc{
+		{
+			MethodName: "Prepare",
+			Handler:    _RootFS_Prepare_Handler,
+		},
+	},
+	Streams:  []grpc.StreamDesc{},
+	Metadata: "github.com/docker/containerd/api/services/rootfs/rootfs.proto",
+}
+
+func (m *PrepareRequest) Marshal() (dAtA []byte, err error) {
+	size := m.Size()
+	dAtA = make([]byte, size)
+	n, err := m.MarshalTo(dAtA)
+	if err != nil {
+		return nil, err
+	}
+	return dAtA[:n], nil
+}
+
+func (m *PrepareRequest) MarshalTo(dAtA []byte) (int, error) {
+	var i int
+	_ = i
+	var l int
+	_ = l
+	if len(m.Layers) > 0 {
+		for _, msg := range m.Layers {
+			dAtA[i] = 0xa
+			i++
+			i = encodeVarintRootfs(dAtA, i, uint64(msg.Size()))
+			n, err := msg.MarshalTo(dAtA[i:])
+			if err != nil {
+				return 0, err
+			}
+			i += n
+		}
+	}
+	return i, nil
+}
+
+func (m *PrepareResponse) Marshal() (dAtA []byte, err error) {
+	size := m.Size()
+	dAtA = make([]byte, size)
+	n, err := m.MarshalTo(dAtA)
+	if err != nil {
+		return nil, err
+	}
+	return dAtA[:n], nil
+}
+
+func (m *PrepareResponse) MarshalTo(dAtA []byte) (int, error) {
+	var i int
+	_ = i
+	var l int
+	_ = l
+	if len(m.ChainID) > 0 {
+		dAtA[i] = 0xa
+		i++
+		i = encodeVarintRootfs(dAtA, i, uint64(len(m.ChainID)))
+		i += copy(dAtA[i:], m.ChainID)
+	}
+	return i, nil
+}
+
+func encodeFixed64Rootfs(dAtA []byte, offset int, v uint64) int {
+	dAtA[offset] = uint8(v)
+	dAtA[offset+1] = uint8(v >> 8)
+	dAtA[offset+2] = uint8(v >> 16)
+	dAtA[offset+3] = uint8(v >> 24)
+	dAtA[offset+4] = uint8(v >> 32)
+	dAtA[offset+5] = uint8(v >> 40)
+	dAtA[offset+6] = uint8(v >> 48)
+	dAtA[offset+7] = uint8(v >> 56)
+	return offset + 8
+}
+func encodeFixed32Rootfs(dAtA []byte, offset int, v uint32) int {
+	dAtA[offset] = uint8(v)
+	dAtA[offset+1] = uint8(v >> 8)
+	dAtA[offset+2] = uint8(v >> 16)
+	dAtA[offset+3] = uint8(v >> 24)
+	return offset + 4
+}
+func encodeVarintRootfs(dAtA []byte, offset int, v uint64) int {
+	for v >= 1<<7 {
+		dAtA[offset] = uint8(v&0x7f | 0x80)
+		v >>= 7
+		offset++
+	}
+	dAtA[offset] = uint8(v)
+	return offset + 1
+}
+func (m *PrepareRequest) Size() (n int) {
+	var l int
+	_ = l
+	if len(m.Layers) > 0 {
+		for _, e := range m.Layers {
+			l = e.Size()
+			n += 1 + l + sovRootfs(uint64(l))
+		}
+	}
+	return n
+}
+
+func (m *PrepareResponse) Size() (n int) {
+	var l int
+	_ = l
+	l = len(m.ChainID)
+	if l > 0 {
+		n += 1 + l + sovRootfs(uint64(l))
+	}
+	return n
+}
+
+func sovRootfs(x uint64) (n int) {
+	for {
+		n++
+		x >>= 7
+		if x == 0 {
+			break
+		}
+	}
+	return n
+}
+func sozRootfs(x uint64) (n int) {
+	return sovRootfs(uint64((x << 1) ^ uint64((int64(x) >> 63))))
+}
+func (this *PrepareRequest) String() string {
+	if this == nil {
+		return "nil"
+	}
+	s := strings.Join([]string{`&PrepareRequest{`,
+		`Layers:` + strings.Replace(fmt.Sprintf("%v", this.Layers), "Descriptor", "containerd_v1_types1.Descriptor", 1) + `,`,
+		`}`,
+	}, "")
+	return s
+}
+func (this *PrepareResponse) String() string {
+	if this == nil {
+		return "nil"
+	}
+	s := strings.Join([]string{`&PrepareResponse{`,
+		`ChainID:` + fmt.Sprintf("%v", this.ChainID) + `,`,
+		`}`,
+	}, "")
+	return s
+}
+func valueToStringRootfs(v interface{}) string {
+	rv := reflect.ValueOf(v)
+	if rv.IsNil() {
+		return "nil"
+	}
+	pv := reflect.Indirect(rv).Interface()
+	return fmt.Sprintf("*%v", pv)
+}
+func (m *PrepareRequest) Unmarshal(dAtA []byte) error {
+	l := len(dAtA)
+	iNdEx := 0
+	for iNdEx < l {
+		preIndex := iNdEx
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if shift >= 64 {
+				return ErrIntOverflowRootfs
+			}
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := dAtA[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		if wireType == 4 {
+			return fmt.Errorf("proto: PrepareRequest: wiretype end group for non-group")
+		}
+		if fieldNum <= 0 {
+			return fmt.Errorf("proto: PrepareRequest: illegal tag %d (wire type %d)", fieldNum, wire)
+		}
+		switch fieldNum {
+		case 1:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Layers", wireType)
+			}
+			var msglen int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowRootfs
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				msglen |= (int(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			if msglen < 0 {
+				return ErrInvalidLengthRootfs
+			}
+			postIndex := iNdEx + msglen
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.Layers = append(m.Layers, &containerd_v1_types1.Descriptor{})
+			if err := m.Layers[len(m.Layers)-1].Unmarshal(dAtA[iNdEx:postIndex]); err != nil {
+				return err
+			}
+			iNdEx = postIndex
+		default:
+			iNdEx = preIndex
+			skippy, err := skipRootfs(dAtA[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthRootfs
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	if iNdEx > l {
+		return io.ErrUnexpectedEOF
+	}
+	return nil
+}
+func (m *PrepareResponse) Unmarshal(dAtA []byte) error {
+	l := len(dAtA)
+	iNdEx := 0
+	for iNdEx < l {
+		preIndex := iNdEx
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if shift >= 64 {
+				return ErrIntOverflowRootfs
+			}
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := dAtA[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		if wireType == 4 {
+			return fmt.Errorf("proto: PrepareResponse: wiretype end group for non-group")
+		}
+		if fieldNum <= 0 {
+			return fmt.Errorf("proto: PrepareResponse: illegal tag %d (wire type %d)", fieldNum, wire)
+		}
+		switch fieldNum {
+		case 1:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field ChainID", wireType)
+			}
+			var stringLen uint64
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowRootfs
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				stringLen |= (uint64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			intStringLen := int(stringLen)
+			if intStringLen < 0 {
+				return ErrInvalidLengthRootfs
+			}
+			postIndex := iNdEx + intStringLen
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.ChainID = github_com_opencontainers_go_digest.Digest(dAtA[iNdEx:postIndex])
+			iNdEx = postIndex
+		default:
+			iNdEx = preIndex
+			skippy, err := skipRootfs(dAtA[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthRootfs
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	if iNdEx > l {
+		return io.ErrUnexpectedEOF
+	}
+	return nil
+}
+func skipRootfs(dAtA []byte) (n int, err error) {
+	l := len(dAtA)
+	iNdEx := 0
+	for iNdEx < l {
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if shift >= 64 {
+				return 0, ErrIntOverflowRootfs
+			}
+			if iNdEx >= l {
+				return 0, io.ErrUnexpectedEOF
+			}
+			b := dAtA[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		wireType := int(wire & 0x7)
+		switch wireType {
+		case 0:
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return 0, ErrIntOverflowRootfs
+				}
+				if iNdEx >= l {
+					return 0, io.ErrUnexpectedEOF
+				}
+				iNdEx++
+				if dAtA[iNdEx-1] < 0x80 {
+					break
+				}
+			}
+			return iNdEx, nil
+		case 1:
+			iNdEx += 8
+			return iNdEx, nil
+		case 2:
+			var length int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return 0, ErrIntOverflowRootfs
+				}
+				if iNdEx >= l {
+					return 0, io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				length |= (int(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			iNdEx += length
+			if length < 0 {
+				return 0, ErrInvalidLengthRootfs
+			}
+			return iNdEx, nil
+		case 3:
+			for {
+				var innerWire uint64
+				var start int = iNdEx
+				for shift := uint(0); ; shift += 7 {
+					if shift >= 64 {
+						return 0, ErrIntOverflowRootfs
+					}
+					if iNdEx >= l {
+						return 0, io.ErrUnexpectedEOF
+					}
+					b := dAtA[iNdEx]
+					iNdEx++
+					innerWire |= (uint64(b) & 0x7F) << shift
+					if b < 0x80 {
+						break
+					}
+				}
+				innerWireType := int(innerWire & 0x7)
+				if innerWireType == 4 {
+					break
+				}
+				next, err := skipRootfs(dAtA[start:])
+				if err != nil {
+					return 0, err
+				}
+				iNdEx = start + next
+			}
+			return iNdEx, nil
+		case 4:
+			return iNdEx, nil
+		case 5:
+			iNdEx += 4
+			return iNdEx, nil
+		default:
+			return 0, fmt.Errorf("proto: illegal wireType %d", wireType)
+		}
+	}
+	panic("unreachable")
+}
+
+var (
+	ErrInvalidLengthRootfs = fmt.Errorf("proto: negative length found during unmarshaling")
+	ErrIntOverflowRootfs   = fmt.Errorf("proto: integer overflow")
+)
+
+func init() {
+	proto.RegisterFile("github.com/docker/containerd/api/services/rootfs/rootfs.proto", fileDescriptorRootfs)
+}
+
+var fileDescriptorRootfs = []byte{
+	// 335 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x8c, 0x90, 0xc1, 0x4f, 0xea, 0x40,
+	0x10, 0xc6, 0xd9, 0xbc, 0x04, 0xf2, 0xf6, 0xe5, 0xbd, 0x97, 0x34, 0x1e, 0x08, 0xc6, 0x2d, 0xe1,
+	0x44, 0x4c, 0xdc, 0x8d, 0x78, 0xd0, 0x0b, 0x17, 0x24, 0x46, 0x6e, 0xa6, 0x1e, 0x3c, 0x97, 0x76,
+	0x58, 0x56, 0xa1, 0xb3, 0xee, 0x6e, 0x49, 0xb8, 0xf9, 0xe7, 0x71, 0xf4, 0x68, 0x3c, 0x10, 0xe9,
+	0x5f, 0x62, 0x68, 0x0b, 0x82, 0x89, 0xd1, 0x4b, 0x67, 0x9a, 0xef, 0x9b, 0xdf, 0x7c, 0xb3, 0xb4,
+	0x2b, 0x95, 0x1b, 0xa7, 0x43, 0x1e, 0xe1, 0x54, 0xc4, 0x18, 0x3d, 0x80, 0x11, 0x11, 0x26, 0x2e,
+	0x54, 0x09, 0x98, 0x58, 0x84, 0x5a, 0x09, 0x0b, 0x66, 0xa6, 0x22, 0xb0, 0xc2, 0x20, 0xba, 0xd1,
+	0xa6, 0x70, 0x6d, 0xd0, 0xa1, 0xf7, 0xf7, 0xc3, 0xcc, 0x67, 0xa7, 0x8d, 0x03, 0x89, 0x12, 0x73,
+	0x45, 0xac, 0xbb, 0xc2, 0xd4, 0x38, 0x94, 0x88, 0x72, 0x02, 0x22, 0xff, 0x1b, 0xa6, 0x23, 0x01,
+	0x53, 0xed, 0xe6, 0xa5, 0x78, 0xf1, 0x6d, 0x00, 0x37, 0xd7, 0x60, 0xc5, 0x14, 0xd3, 0xc4, 0x15,
+	0xdf, 0x72, 0xb2, 0xf7, 0xc3, 0xc9, 0x18, 0x6c, 0x64, 0x94, 0x76, 0x68, 0x76, 0xda, 0x82, 0xd1,
+	0x1a, 0xd0, 0x7f, 0x37, 0x06, 0x74, 0x68, 0x20, 0x80, 0xc7, 0x14, 0xac, 0xf3, 0xce, 0x69, 0x75,
+	0x12, 0xce, 0xc1, 0xd8, 0x3a, 0x69, 0xfe, 0x6a, 0xff, 0xe9, 0xf8, 0x7c, 0xef, 0x44, 0x9e, 0x33,
+	0x79, 0x7f, 0x0b, 0x0a, 0x4a, 0x7b, 0xeb, 0x9e, 0xfe, 0xdf, 0xa2, 0xac, 0xc6, 0xc4, 0x82, 0x77,
+	0x47, 0x6b, 0xd1, 0x38, 0x54, 0x89, 0x8a, 0xeb, 0xa4, 0x49, 0xda, 0xbf, 0x7b, 0xdd, 0xc5, 0xd2,
+	0xaf, 0xbc, 0x2e, 0xfd, 0xe3, 0x9d, 0xe8, 0xa8, 0x21, 0xd9, 0xae, 0xb0, 0x42, 0xe2, 0x49, 0xac,
+	0x24, 0x58, 0xc7, 0xfb, 0x79, 0xc9, 0x96, 0x7e, 0xed, 0x72, 0x0d, 0x19, 0xf4, 0x83, 0x0d, 0xad,
+	0x13, 0xd0, 0x6a, 0x80, 0xe8, 0xae, 0x6e, 0xbd, 0x6b, 0x5a, 0x2b, 0xb7, 0x7a, 0x47, 0x9f, 0x92,
+	0xee, 0x1f, 0xd6, 0x60, 0x5f, 0xc9, 0x45, 0xd8, 0x5e, 0x7d, 0xb1, 0x62, 0x95, 0x97, 0x15, 0xab,
+	0x3c, 0x65, 0x8c, 0x2c, 0x32, 0x46, 0x9e, 0x33, 0x46, 0xde, 0x32, 0x46, 0x86, 0xd5, 0xfc, 0xad,
+	0xce, 0xde, 0x03, 0x00, 0x00, 0xff, 0xff, 0x4c, 0xa2, 0x59, 0x7e, 0x2c, 0x02, 0x00, 0x00,
+}

api/services/rootfs/rootfs.proto

@@ -0,0 +1,38 @@
+syntax = "proto3";
+
+package containerd.v1;
+
+import "gogoproto/gogo.proto";
+import "google/protobuf/empty.proto";
+import "github.com/docker/containerd/api/types/mount/mount.proto";
+import "github.com/docker/containerd/api/types/descriptor/descriptor.proto";
+
+service RootFS {
+	rpc Prepare(PrepareRequest) returns (PrepareResponse);
+
+	// TODO: Add method for initializing and retrieving mounts
+	//rpc InitMounts(InitRequest) returns (MountResponse);
+	//rpc Mounts(MountRequest) returns (MountResponse);
+}
+
+message PrepareRequest {
+	repeated containerd.v1.types.Descriptor layers = 1;
+}
+
+message PrepareResponse {
+	string chainid = 1 [(gogoproto.customtype) = "github.com/opencontainers/go-digest.Digest", (gogoproto.nullable) = false, (gogoproto.customname) = "ChainID"];
+}
+
+//message InitRequest {
+//	string name = 1;
+//	string chainID = 2;
+//	bool Readonly = 3;
+//}
+//
+//message MountRequest {
+//	string name = 1;
+//}
+//
+//message MountResponse {
+//	repeated containerd.v1.types.Mount mounts = 1;
+//}

api/types/descriptor/descriptor.pb.go

@@ -0,0 +1,417 @@
+// Code generated by protoc-gen-gogo.
+// source: github.com/docker/containerd/api/types/descriptor/descriptor.proto
+// DO NOT EDIT!
+
+/*
+	Package descriptor is a generated protocol buffer package.
+
+	It is generated from these files:
+		github.com/docker/containerd/api/types/descriptor/descriptor.proto
+
+	It has these top-level messages:
+		Descriptor
+*/
+package descriptor
+
+import proto "github.com/gogo/protobuf/proto"
+import fmt "fmt"
+import math "math"
+import _ "github.com/gogo/protobuf/gogoproto"
+
+import github_com_opencontainers_go_digest "github.com/opencontainers/go-digest"
+
+import strings "strings"
+import reflect "reflect"
+
+import io "io"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.GoGoProtoPackageIsVersion2 // please upgrade the proto package
+
+type Descriptor struct {
+	MediaType string                                     `protobuf:"bytes,1,opt,name=mediaType,proto3" json:"mediaType,omitempty"`
+	Digest    github_com_opencontainers_go_digest.Digest `protobuf:"bytes,2,opt,name=digest,proto3,customtype=github.com/opencontainers/go-digest.Digest" json:"digest"`
+	MediaSize int64                                      `protobuf:"varint,3,opt,name=mediaSize,proto3" json:"mediaSize,omitempty"`
+}
+
+func (m *Descriptor) Reset()                    { *m = Descriptor{} }
+func (*Descriptor) ProtoMessage()               {}
+func (*Descriptor) Descriptor() ([]byte, []int) { return fileDescriptorDescriptor, []int{0} }
+
+func init() {
+	proto.RegisterType((*Descriptor)(nil), "containerd.v1.types.Descriptor")
+}
+func (m *Descriptor) Marshal() (dAtA []byte, err error) {
+	size := m.Size()
+	dAtA = make([]byte, size)
+	n, err := m.MarshalTo(dAtA)
+	if err != nil {
+		return nil, err
+	}
+	return dAtA[:n], nil
+}
+
+func (m *Descriptor) MarshalTo(dAtA []byte) (int, error) {
+	var i int
+	_ = i
+	var l int
+	_ = l
+	if len(m.MediaType) > 0 {
+		dAtA[i] = 0xa
+		i++
+		i = encodeVarintDescriptor(dAtA, i, uint64(len(m.MediaType)))
+		i += copy(dAtA[i:], m.MediaType)
+	}
+	if len(m.Digest) > 0 {
+		dAtA[i] = 0x12
+		i++
+		i = encodeVarintDescriptor(dAtA, i, uint64(len(m.Digest)))
+		i += copy(dAtA[i:], m.Digest)
+	}
+	if m.MediaSize != 0 {
+		dAtA[i] = 0x18
+		i++
+		i = encodeVarintDescriptor(dAtA, i, uint64(m.MediaSize))
+	}
+	return i, nil
+}
+
+func encodeFixed64Descriptor(dAtA []byte, offset int, v uint64) int {
+	dAtA[offset] = uint8(v)
+	dAtA[offset+1] = uint8(v >> 8)
+	dAtA[offset+2] = uint8(v >> 16)
+	dAtA[offset+3] = uint8(v >> 24)
+	dAtA[offset+4] = uint8(v >> 32)
+	dAtA[offset+5] = uint8(v >> 40)
+	dAtA[offset+6] = uint8(v >> 48)
+	dAtA[offset+7] = uint8(v >> 56)
+	return offset + 8
+}
+func encodeFixed32Descriptor(dAtA []byte, offset int, v uint32) int {
+	dAtA[offset] = uint8(v)
+	dAtA[offset+1] = uint8(v >> 8)
+	dAtA[offset+2] = uint8(v >> 16)
+	dAtA[offset+3] = uint8(v >> 24)
+	return offset + 4
+}
+func encodeVarintDescriptor(dAtA []byte, offset int, v uint64) int {
+	for v >= 1<<7 {
+		dAtA[offset] = uint8(v&0x7f | 0x80)
+		v >>= 7
+		offset++
+	}
+	dAtA[offset] = uint8(v)
+	return offset + 1
+}
+func (m *Descriptor) Size() (n int) {
+	var l int
+	_ = l
+	l = len(m.MediaType)
+	if l > 0 {
+		n += 1 + l + sovDescriptor(uint64(l))
+	}
+	l = len(m.Digest)
+	if l > 0 {
+		n += 1 + l + sovDescriptor(uint64(l))
+	}
+	if m.MediaSize != 0 {
+		n += 1 + sovDescriptor(uint64(m.MediaSize))
+	}
+	return n
+}
+
+func sovDescriptor(x uint64) (n int) {
+	for {
+		n++
+		x >>= 7
+		if x == 0 {
+			break
+		}
+	}
+	return n
+}
+func sozDescriptor(x uint64) (n int) {
+	return sovDescriptor(uint64((x << 1) ^ uint64((int64(x) >> 63))))
+}
+func (this *Descriptor) String() string {
+	if this == nil {
+		return "nil"
+	}
+	s := strings.Join([]string{`&Descriptor{`,
+		`MediaType:` + fmt.Sprintf("%v", this.MediaType) + `,`,
+		`Digest:` + fmt.Sprintf("%v", this.Digest) + `,`,
+		`MediaSize:` + fmt.Sprintf("%v", this.MediaSize) + `,`,
+		`}`,
+	}, "")
+	return s
+}
+func valueToStringDescriptor(v interface{}) string {
+	rv := reflect.ValueOf(v)
+	if rv.IsNil() {
+		return "nil"
+	}
+	pv := reflect.Indirect(rv).Interface()
+	return fmt.Sprintf("*%v", pv)
+}
+func (m *Descriptor) Unmarshal(dAtA []byte) error {
+	l := len(dAtA)
+	iNdEx := 0
+	for iNdEx < l {
+		preIndex := iNdEx
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if shift >= 64 {
+				return ErrIntOverflowDescriptor
+			}
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := dAtA[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		if wireType == 4 {
+			return fmt.Errorf("proto: Descriptor: wiretype end group for non-group")
+		}
+		if fieldNum <= 0 {
+			return fmt.Errorf("proto: Descriptor: illegal tag %d (wire type %d)", fieldNum, wire)
+		}
+		switch fieldNum {
+		case 1:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field MediaType", wireType)
+			}
+			var stringLen uint64
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowDescriptor
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				stringLen |= (uint64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			intStringLen := int(stringLen)
+			if intStringLen < 0 {
+				return ErrInvalidLengthDescriptor
+			}
+			postIndex := iNdEx + intStringLen
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.MediaType = string(dAtA[iNdEx:postIndex])
+			iNdEx = postIndex
+		case 2:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Digest", wireType)
+			}
+			var stringLen uint64
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowDescriptor
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				stringLen |= (uint64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			intStringLen := int(stringLen)
+			if intStringLen < 0 {
+				return ErrInvalidLengthDescriptor
+			}
+			postIndex := iNdEx + intStringLen
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.Digest = github_com_opencontainers_go_digest.Digest(dAtA[iNdEx:postIndex])
+			iNdEx = postIndex
+		case 3:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field MediaSize", wireType)
+			}
+			m.MediaSize = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowDescriptor
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.MediaSize |= (int64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		default:
+			iNdEx = preIndex
+			skippy, err := skipDescriptor(dAtA[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthDescriptor
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	if iNdEx > l {
+		return io.ErrUnexpectedEOF
+	}
+	return nil
+}
+func skipDescriptor(dAtA []byte) (n int, err error) {
+	l := len(dAtA)
+	iNdEx := 0
+	for iNdEx < l {
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if shift >= 64 {
+				return 0, ErrIntOverflowDescriptor
+			}
+			if iNdEx >= l {
+				return 0, io.ErrUnexpectedEOF
+			}
+			b := dAtA[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		wireType := int(wire & 0x7)
+		switch wireType {
+		case 0:
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return 0, ErrIntOverflowDescriptor
+				}
+				if iNdEx >= l {
+					return 0, io.ErrUnexpectedEOF
+				}
+				iNdEx++
+				if dAtA[iNdEx-1] < 0x80 {
+					break
+				}
+			}
+			return iNdEx, nil
+		case 1:
+			iNdEx += 8
+			return iNdEx, nil
+		case 2:
+			var length int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return 0, ErrIntOverflowDescriptor
+				}
+				if iNdEx >= l {
+					return 0, io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				length |= (int(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			iNdEx += length
+			if length < 0 {
+				return 0, ErrInvalidLengthDescriptor
+			}
+			return iNdEx, nil
+		case 3:
+			for {
+				var innerWire uint64
+				var start int = iNdEx
+				for shift := uint(0); ; shift += 7 {
+					if shift >= 64 {
+						return 0, ErrIntOverflowDescriptor
+					}
+					if iNdEx >= l {
+						return 0, io.ErrUnexpectedEOF
+					}
+					b := dAtA[iNdEx]
+					iNdEx++
+					innerWire |= (uint64(b) & 0x7F) << shift
+					if b < 0x80 {
+						break
+					}
+				}
+				innerWireType := int(innerWire & 0x7)
+				if innerWireType == 4 {
+					break
+				}
+				next, err := skipDescriptor(dAtA[start:])
+				if err != nil {
+					return 0, err
+				}
+				iNdEx = start + next
+			}
+			return iNdEx, nil
+		case 4:
+			return iNdEx, nil
+		case 5:
+			iNdEx += 4
+			return iNdEx, nil
+		default:
+			return 0, fmt.Errorf("proto: illegal wireType %d", wireType)
+		}
+	}
+	panic("unreachable")
+}
+
+var (
+	ErrInvalidLengthDescriptor = fmt.Errorf("proto: negative length found during unmarshaling")
+	ErrIntOverflowDescriptor   = fmt.Errorf("proto: integer overflow")
+)
+
+func init() {
+	proto.RegisterFile("github.com/docker/containerd/api/types/descriptor/descriptor.proto", fileDescriptorDescriptor)
+}
+
+var fileDescriptorDescriptor = []byte{
+	// 230 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0x72, 0x4a, 0xcf, 0x2c, 0xc9,
+	0x28, 0x4d, 0xd2, 0x4b, 0xce, 0xcf, 0xd5, 0x4f, 0xc9, 0x4f, 0xce, 0x4e, 0x2d, 0xd2, 0x4f, 0xce,
+	0xcf, 0x2b, 0x49, 0xcc, 0xcc, 0x4b, 0x2d, 0x4a, 0xd1, 0x4f, 0x2c, 0xc8, 0xd4, 0x2f, 0xa9, 0x2c,
+	0x48, 0x2d, 0xd6, 0x4f, 0x49, 0x2d, 0x4e, 0x2e, 0xca, 0x2c, 0x28, 0xc9, 0x2f, 0x42, 0x62, 0xea,
+	0x15, 0x14, 0xe5, 0x97, 0xe4, 0x0b, 0x09, 0x23, 0x74, 0xe8, 0x95, 0x19, 0xea, 0x81, 0x35, 0x48,
+	0x89, 0xa4, 0xe7, 0xa7, 0xe7, 0x83, 0xe5, 0xf5, 0x41, 0x2c, 0x88, 0x52, 0xa5, 0x29, 0x8c, 0x5c,
+	0x5c, 0x2e, 0x70, 0xfd, 0x42, 0x32, 0x5c, 0x9c, 0xb9, 0xa9, 0x29, 0x99, 0x89, 0x21, 0x95, 0x05,
+	0xa9, 0x12, 0x8c, 0x0a, 0x8c, 0x1a, 0x9c, 0x41, 0x08, 0x01, 0x21, 0x2f, 0x2e, 0xb6, 0x94, 0xcc,
+	0xf4, 0xd4, 0xe2, 0x12, 0x09, 0x26, 0x90, 0x94, 0x93, 0xd1, 0x89, 0x7b, 0xf2, 0x0c, 0xb7, 0xee,
+	0xc9, 0x6b, 0x21, 0xb9, 0x39, 0xbf, 0x20, 0x35, 0x0f, 0x6e, 0x7d, 0xb1, 0x7e, 0x7a, 0xbe, 0x2e,
+	0x44, 0x8b, 0x9e, 0x0b, 0x98, 0x0a, 0x82, 0x9a, 0x00, 0xb7, 0x29, 0x38, 0xb3, 0x2a, 0x55, 0x82,
+	0x59, 0x81, 0x51, 0x83, 0x39, 0x08, 0x21, 0xe0, 0x24, 0x71, 0xe2, 0xa1, 0x1c, 0xc3, 0x8d, 0x87,
+	0x72, 0x0c, 0x0d, 0x8f, 0xe4, 0x18, 0x4f, 0x3c, 0x92, 0x63, 0xbc, 0xf0, 0x48, 0x8e, 0xf1, 0xc1,
+	0x23, 0x39, 0xc6, 0x24, 0x36, 0xb0, 0xbb, 0x8d, 0x01, 0x01, 0x00, 0x00, 0xff, 0xff, 0xf2, 0x3c,
+	0x86, 0x2d, 0x28, 0x01, 0x00, 0x00,
+}

api/types/descriptor/descriptor.proto

@@ -0,0 +1,11 @@
+syntax = "proto3";
+
+package containerd.v1.types;
+
+import "gogoproto/gogo.proto";
+
+message Descriptor {
+	string mediaType = 1;
+	string digest = 2 [(gogoproto.customtype) = "github.com/opencontainers/go-digest.Digest", (gogoproto.nullable) = false];
+	int64 mediaSize = 3;
+}

cmd/containerd/builtins.go

@@ -7,6 +7,7 @@ import (
 	_ "github.com/docker/containerd/services/execution"
 	_ "github.com/docker/containerd/services/healthcheck"
 	_ "github.com/docker/containerd/services/metrics"
+	_ "github.com/docker/containerd/services/rootfs"
 	_ "github.com/docker/containerd/snapshot/btrfs"
 	_ "github.com/docker/containerd/snapshot/overlay"
 )

rootfs/apply.go

@@ -16,9 +16,13 @@ import (
 	"github.com/pkg/errors"
 )
 
+type Preparer interface {
+	Prepare(ctx context.Context, layers []ocispec.Descriptor) (digest.Digest, error)
+}
+
 type Mounter interface {
-	Mount(mounts ...containerd.Mount) error
+	Mount(target string, mounts ...containerd.Mount) error
-	Unmount(mounts ...containerd.Mount) error
+	Unmount(target string) error
 }
 
 // ApplyLayer applies the layer to the provided parent. The resulting snapshot
@@ -51,13 +55,13 @@ func ApplyLayer(snapshots snapshot.Snapshotter, mounter Mounter, rd io.Reader, p
 		return "", err
 	}
 
-	if err := mounter.Mount(mounts...); err != nil {
+	if err := mounter.Mount(dir, mounts...); err != nil {
 		if err := snapshots.Remove(ctx, key); err != nil {
 			log.L.WithError(err).Error("snapshot rollback failed")
 		}
 		return "", err
 	}
-	defer mounter.Unmount(mounts...)
+	defer mounter.Unmount(dir)
 
 	rd, err = dockerarchive.DecompressStream(rd)
 	if err != nil {
@@ -74,6 +78,9 @@ func ApplyLayer(snapshots snapshot.Snapshotter, mounter Mounter, rd io.Reader, p
 	if parent != "" {
 		chainID = identity.ChainID([]digest.Digest{parent, chainID})
 	}
+	if _, err := snapshots.Stat(ctx, chainID.String()); err == nil {
+		return diffID, nil //TODO: call snapshots.Remove(ctx, key) once implemented
+	}
 
 	return diffID, snapshots.Commit(ctx, chainID.String(), key)
 }
@@ -90,7 +97,7 @@ func Prepare(ctx context.Context, snapshots snapshot.Snapshotter, mounter Mounte
 	// rootfs Controller.
 	//
 	// Just pass them in for now.
-	openBlob func(digest.Digest) (io.ReadCloser, error),
+	openBlob func(context.Context, digest.Digest) (io.ReadCloser, error),
 	resolveDiffID func(digest.Digest) digest.Digest,
 	registerDiffID func(diffID, dgst digest.Digest) error) (digest.Digest, error) {
 	var (
@@ -116,7 +123,7 @@ func Prepare(ctx context.Context, snapshots snapshot.Snapshotter, mounter Mounte
 			}
 		}
 
-		rc, err := openBlob(layerDigest)
+		rc, err := openBlob(ctx, layerDigest)
 		if err != nil {
 			return "", err
 		}

services/rootfs/preparer.go

@@ -0,0 +1,39 @@
+package rootfs
+
+import (
+	"context"
+
+	rootfsapi "github.com/docker/containerd/api/services/rootfs"
+	containerd_v1_types "github.com/docker/containerd/api/types/descriptor"
+	"github.com/docker/containerd/rootfs"
+	digest "github.com/opencontainers/go-digest"
+	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
+)
+
+func NewPreparerFromClient(client rootfsapi.RootFSClient) rootfs.Preparer {
+	return remotePreparer{
+		client: client,
+	}
+}
+
+type remotePreparer struct {
+	client rootfsapi.RootFSClient
+}
+
+func (rp remotePreparer) Prepare(ctx context.Context, layers []ocispec.Descriptor) (digest.Digest, error) {
+	pr := rootfsapi.PrepareRequest{
+		Layers: make([]*containerd_v1_types.Descriptor, len(layers)),
+	}
+	for i, l := range layers {
+		pr.Layers[i] = &containerd_v1_types.Descriptor{
+			MediaType: l.MediaType,
+			Digest:    l.Digest,
+			MediaSize: l.Size,
+		}
+	}
+	resp, err := rp.client.Prepare(ctx, &pr)
+	if err != nil {
+		return "", nil
+	}
+	return resp.ChainID, nil
+}

services/rootfs/service.go

@@ -0,0 +1,86 @@
+package rootfs
+
+import (
+	"syscall"
+
+	"github.com/docker/containerd"
+	rootfsapi "github.com/docker/containerd/api/services/rootfs"
+	"github.com/docker/containerd/content"
+	"github.com/docker/containerd/log"
+	"github.com/docker/containerd/plugin"
+	"github.com/docker/containerd/rootfs"
+	"github.com/docker/containerd/snapshot"
+	digest "github.com/opencontainers/go-digest"
+	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
+	"golang.org/x/net/context"
+	"google.golang.org/grpc"
+)
+
+func init() {
+	plugin.Register("rootfs-grpc", &plugin.Registration{
+		Type: plugin.GRPCPlugin,
+		Init: func(ic *plugin.InitContext) (interface{}, error) {
+			return NewService(ic.Store, ic.Snapshotter)
+		},
+	})
+}
+
+type Service struct {
+	store       *content.Store
+	snapshotter snapshot.Snapshotter
+}
+
+func NewService(store *content.Store, snapshotter snapshot.Snapshotter) (*Service, error) {
+	return &Service{
+		store:       store,
+		snapshotter: snapshotter,
+	}, nil
+}
+
+func (s *Service) Register(gs *grpc.Server) error {
+	rootfsapi.RegisterRootFSServer(gs, s)
+	return nil
+}
+
+func (s *Service) Prepare(ctx context.Context, pr *rootfsapi.PrepareRequest) (*rootfsapi.PrepareResponse, error) {
+	layers := make([]ocispec.Descriptor, len(pr.Layers))
+	for i, l := range pr.Layers {
+		layers[i] = ocispec.Descriptor{
+			MediaType: l.MediaType,
+			Digest:    l.Digest,
+			Size:      l.MediaSize,
+		}
+	}
+	log.G(ctx).Infof("Preparing %#v", layers)
+	chainID, err := rootfs.Prepare(ctx, s.snapshotter, mounter{}, layers, s.store.Reader, emptyResolver, noopRegister)
+	if err != nil {
+		log.G(ctx).Errorf("Rootfs Prepare failed!: %v", err)
+		return nil, err
+	}
+	log.G(ctx).Infof("ChainID %#v", chainID)
+	return &rootfsapi.PrepareResponse{
+		ChainID: chainID,
+	}, nil
+}
+
+type mounter struct{}
+
+func (mounter) Mount(dir string, mounts ...containerd.Mount) error {
+	return containerd.MountAll(mounts, dir)
+}
+
+func (mounter) Unmount(dir string) error {
+	return syscall.Unmount(dir, 0)
+}
+
+func emptyResolver(digest.Digest) digest.Digest {
+	return digest.Digest("")
+}
+
+func noopRegister(digest.Digest, digest.Digest) error {
+	return nil
+}
+
+//func (s *Service) Mounts(ctx context.Context, mr *rootfsapi.MountRequest) (*rootfsapi.MountResponse, error) {
+//
+//}