Remove duplication in pagination

pkg/backend/aio.go

@@ -152,7 +152,7 @@ func (s *Server) UpdateAioController(_ context.Context, in *pb.UpdateAioControll
 // ListAioControllers lists Aio controllers
 func (s *Server) ListAioControllers(_ context.Context, in *pb.ListAioControllersRequest) (*pb.ListAioControllersResponse, error) {
 	log.Printf("ListAioControllers: Received from client: %v", in)
-	size, offset, perr := server.ExtractPagination(in.PageSize, in.PageToken, s.Pagination)
+	pageToken, perr := s.Pagination.PageToken(in.PageSize, in.PageToken)
 	if perr != nil {
 		log.Printf("error: %v", perr)
 		return nil, perr
@@ -164,20 +164,14 @@ func (s *Server) ListAioControllers(_ context.Context, in *pb.ListAioControllers
 		return nil, err
 	}
 	log.Printf("Received from SPDK: %v", result)
-	token := ""
-	log.Printf("Limiting result len(%d) to [%d:%d]", len(result), offset, size)
-	result, hasMoreElements := server.LimitPagination(result, offset, size)
-	if hasMoreElements {
-		token = uuid.New().String()
-		s.Pagination[token] = offset + size
-	}
 	Blobarray := make([]*pb.AioController, len(result))
 	for i := range result {
 		r := &result[i]
 		Blobarray[i] = &pb.AioController{Handle: &pc.ObjectKey{Value: r.Name}, BlockSize: r.BlockSize, BlocksCount: r.NumBlocks}
 	}
 	sortAioControllers(Blobarray)
-	return &pb.ListAioControllersResponse{AioControllers: Blobarray, NextPageToken: token}, nil
+	page := server.LimitToPage(pageToken, Blobarray)
+	return &pb.ListAioControllersResponse{AioControllers: page.List, NextPageToken: page.NextToken}, nil
 }
 
 // GetAioController gets an Aio controller

pkg/backend/backend.go

@@ -8,6 +8,7 @@ package backend
 import (
 	"github.com/opiproject/gospdk/spdk"
 	pb "github.com/opiproject/opi-api/storage/v1alpha1/gen/go"
+	"github.com/opiproject/opi-spdk-bridge/pkg/server"
 )
 
 // TODO: can we combine all of volume types into a single list?
@@ -28,7 +29,7 @@ type Server struct {
 
 	rpc        spdk.JSONRPC
 	Volumes    VolumeParameters
-	Pagination map[string]int
+	Pagination server.Pagination
 }
 
 // NewServer creates initialized instance of BackEnd server communicating
@@ -41,6 +42,6 @@ func NewServer(jsonRPC spdk.JSONRPC) *Server {
 			NullVolumes: make(map[string]*pb.NullDebug),
 			NvmeVolumes: make(map[string]*pb.NVMfRemoteController),
 		},
-		Pagination: make(map[string]int),
+		Pagination: server.NewPagination(),
 	}
 }

pkg/backend/null.go

@@ -152,7 +152,7 @@ func (s *Server) UpdateNullDebug(_ context.Context, in *pb.UpdateNullDebugReques
 // ListNullDebugs lists Null Debug instances
 func (s *Server) ListNullDebugs(_ context.Context, in *pb.ListNullDebugsRequest) (*pb.ListNullDebugsResponse, error) {
 	log.Printf("ListNullDebugs: Received from client: %v", in)
-	size, offset, perr := server.ExtractPagination(in.PageSize, in.PageToken, s.Pagination)
+	pageToken, perr := s.Pagination.PageToken(in.PageSize, in.PageToken)
 	if perr != nil {
 		log.Printf("error: %v", perr)
 		return nil, perr
@@ -164,20 +164,14 @@ func (s *Server) ListNullDebugs(_ context.Context, in *pb.ListNullDebugsRequest)
 		return nil, err
 	}
 	log.Printf("Received from SPDK: %v", result)
-	token := ""
-	log.Printf("Limiting result len(%d) to [%d:%d]", len(result), offset, size)
-	result, hasMoreElements := server.LimitPagination(result, offset, size)
-	if hasMoreElements {
-		token = uuid.New().String()
-		s.Pagination[token] = offset + size
-	}
 	Blobarray := make([]*pb.NullDebug, len(result))
 	for i := range result {
 		r := &result[i]
 		Blobarray[i] = &pb.NullDebug{Handle: &pc.ObjectKey{Value: r.Name}, Uuid: &pc.Uuid{Value: r.UUID}, BlockSize: r.BlockSize, BlocksCount: r.NumBlocks}
 	}
 	sortNullDebugs(Blobarray)
-	return &pb.ListNullDebugsResponse{NullDebugs: Blobarray, NextPageToken: token}, nil
+	page := server.LimitToPage(pageToken, Blobarray)
+	return &pb.ListNullDebugsResponse{NullDebugs: page.List, NextPageToken: page.NextToken}, nil
 }
 
 // GetNullDebug gets a a Null Debug instance

pkg/backend/nvme.go

@@ -114,7 +114,7 @@ func (s *Server) NVMfRemoteControllerReset(_ context.Context, in *pb.NVMfRemoteC
 // ListNVMfRemoteControllers lists an NVMf remote controllers
 func (s *Server) ListNVMfRemoteControllers(_ context.Context, in *pb.ListNVMfRemoteControllersRequest) (*pb.ListNVMfRemoteControllersResponse, error) {
 	log.Printf("ListNVMfRemoteControllers: Received from client: %v", in)
-	size, offset, perr := server.ExtractPagination(in.PageSize, in.PageToken, s.Pagination)
+	pageToken, perr := s.Pagination.PageToken(in.PageSize, in.PageToken)
 	if perr != nil {
 		log.Printf("error: %v", perr)
 		return nil, perr
@@ -126,13 +126,6 @@ func (s *Server) ListNVMfRemoteControllers(_ context.Context, in *pb.ListNVMfRem
 		return nil, err
 	}
 	log.Printf("Received from SPDK: %v", result)
-	token := ""
-	log.Printf("Limiting result len(%d) to [%d:%d]", len(result), offset, size)
-	result, hasMoreElements := server.LimitPagination(result, offset, size)
-	if hasMoreElements {
-		token = uuid.New().String()
-		s.Pagination[token] = offset + size
-	}
 	Blobarray := make([]*pb.NVMfRemoteController, len(result))
 	for i := range result {
 		r := &result[i]
@@ -148,7 +141,8 @@ func (s *Server) ListNVMfRemoteControllers(_ context.Context, in *pb.ListNVMfRem
 		}
 	}
 	sortNVMfRemoteControllers(Blobarray)
-	return &pb.ListNVMfRemoteControllersResponse{NvMfRemoteControllers: Blobarray, NextPageToken: token}, nil
+	page := server.LimitToPage(pageToken, Blobarray)
+	return &pb.ListNVMfRemoteControllersResponse{NvMfRemoteControllers: page.List, NextPageToken: page.NextToken}, nil
 }
 
 // GetNVMfRemoteController gets an NVMf remote controller

pkg/frontend/blk.go

@@ -110,7 +110,7 @@ func (s *Server) UpdateVirtioBlk(_ context.Context, in *pb.UpdateVirtioBlkReques
 // ListVirtioBlks lists Virtio block devices
 func (s *Server) ListVirtioBlks(_ context.Context, in *pb.ListVirtioBlksRequest) (*pb.ListVirtioBlksResponse, error) {
 	log.Printf("ListVirtioBlks: Received from client: %v", in)
-	size, offset, perr := server.ExtractPagination(in.PageSize, in.PageToken, s.Pagination)
+	pageToken, perr := s.Pagination.PageToken(in.PageSize, in.PageToken)
 	if perr != nil {
 		log.Printf("error: %v", perr)
 		return nil, perr
@@ -122,13 +122,6 @@ func (s *Server) ListVirtioBlks(_ context.Context, in *pb.ListVirtioBlksRequest)
 		return nil, err
 	}
 	log.Printf("Received from SPDK: %v", result)
-	token := ""
-	log.Printf("Limiting result len(%d) to [%d:%d]", len(result), offset, size)
-	result, hasMoreElements := server.LimitPagination(result, offset, size)
-	if hasMoreElements {
-		token = uuid.New().String()
-		s.Pagination[token] = offset + size
-	}
 	Blobarray := make([]*pb.VirtioBlk, len(result))
 	for i := range result {
 		r := &result[i]
@@ -138,8 +131,8 @@ func (s *Server) ListVirtioBlks(_ context.Context, in *pb.ListVirtioBlksRequest)
 			VolumeId: &pc.ObjectKey{Value: "TBD"}}
 	}
 	sortVirtioBlks(Blobarray)
-
-	return &pb.ListVirtioBlksResponse{VirtioBlks: Blobarray, NextPageToken: token}, nil
+	page := server.LimitToPage(pageToken, Blobarray)
+	return &pb.ListVirtioBlksResponse{VirtioBlks: page.List, NextPageToken: page.NextToken}, nil
 }
 
 // GetVirtioBlk gets a Virtio block device

pkg/frontend/blk_test.go

@@ -285,12 +285,16 @@ func TestFrontEnd_ListVirtioBlks(t *testing.T) {
 			"subsystem-test",
 			[]*pb.VirtioBlk{
 				{
-					Id:       &pc.ObjectKey{Value: "virtio-blk-42"},
+					Id:       &pc.ObjectKey{Value: "VblkEmu0pf2"},
 					PcieId:   &pb.PciEndpoint{PhysicalFunction: int32(1)},
 					VolumeId: &pc.ObjectKey{Value: "TBD"},
 				},
 			},
-			[]string{`{"jsonrpc":"2.0","id":%d,"result":[{"ctrlr":"VblkEmu0pf0","emulation_manager":"mlx5_0","type":"virtio_blk","pci_index":0,"pci_bdf":"ca:00.4"},{"ctrlr":"virtio-blk-42","emulation_manager":"mlx5_0","type":"virtio_blk","pci_index":0,"pci_bdf":"ca:00.4"},{"ctrlr":"VblkEmu0pf2","emulation_manager":"mlx5_0","type":"virtio_blk","pci_index":0,"pci_bdf":"ca:00.4"}],"error":{"code":0,"message":""}}`},
+			[]string{`{"jsonrpc":"2.0","id":%d,"result":[
+				{"ctrlr":"VblkEmu0pf0","emulation_manager":"mlx5_0","type":"virtio_blk","pci_index":0,"pci_bdf":"ca:00.4"},
+				{"ctrlr":"virtio-blk-42","emulation_manager":"mlx5_0","type":"virtio_blk","pci_index":0,"pci_bdf":"ca:00.4"},
+				{"ctrlr":"VblkEmu0pf2","emulation_manager":"mlx5_0","type":"virtio_blk","pci_index":0,"pci_bdf":"ca:00.4"}
+				],"error":{"code":0,"message":""}}`},
 			codes.OK,
 			"",
 			true,

pkg/frontend/frontend.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/opiproject/gospdk/spdk"
 	pb "github.com/opiproject/opi-api/storage/v1alpha1/gen/go"
+	"github.com/opiproject/opi-spdk-bridge/pkg/server"
 )
 
 // SubsystemListener interface is used to provide SPDK call params to create/delete
@@ -42,7 +43,7 @@ type Server struct {
 	rpc        spdk.JSONRPC
 	Nvme       NvmeParameters
 	Virt       VirtioParameters
-	Pagination map[string]int
+	Pagination server.Pagination
 }
 
 // NewServer creates initialized instance of FrontEnd server communicating
@@ -61,7 +62,7 @@ func NewServer(jsonRPC spdk.JSONRPC) *Server {
 			ScsiCtrls: make(map[string]*pb.VirtioScsiController),
 			ScsiLuns:  make(map[string]*pb.VirtioScsiLun),
 		},
-		Pagination: make(map[string]int),
+		Pagination: server.NewPagination(),
 	}
 }
 

pkg/frontend/nvme.go

@@ -188,7 +188,7 @@ func (s *Server) UpdateNVMeSubsystem(_ context.Context, in *pb.UpdateNVMeSubsyst
 // ListNVMeSubsystems lists NVMe Subsystems
 func (s *Server) ListNVMeSubsystems(_ context.Context, in *pb.ListNVMeSubsystemsRequest) (*pb.ListNVMeSubsystemsResponse, error) {
 	log.Printf("ListNVMeSubsystems: Received from client: %v", in)
-	size, offset, perr := server.ExtractPagination(in.PageSize, in.PageToken, s.Pagination)
+	pageToken, perr := s.Pagination.PageToken(in.PageSize, in.PageToken)
 	if perr != nil {
 		log.Printf("error: %v", perr)
 		return nil, perr
@@ -200,20 +200,14 @@ func (s *Server) ListNVMeSubsystems(_ context.Context, in *pb.ListNVMeSubsystems
 		return nil, err
 	}
 	log.Printf("Received from SPDK: %v", result)
-	token := ""
-	log.Printf("Limiting result len(%d) to [%d:%d]", len(result), offset, size)
-	result, hasMoreElements := server.LimitPagination(result, offset, size)
-	if hasMoreElements {
-		token = uuid.New().String()
-		s.Pagination[token] = offset + size
-	}
 	Blobarray := make([]*pb.NVMeSubsystem, len(result))
 	for i := range result {
 		r := &result[i]
 		Blobarray[i] = &pb.NVMeSubsystem{Spec: &pb.NVMeSubsystemSpec{Nqn: r.Nqn, SerialNumber: r.SerialNumber, ModelNumber: r.ModelNumber}}
 	}
 	sortNVMeSubsystems(Blobarray)
-	return &pb.ListNVMeSubsystemsResponse{NvMeSubsystems: Blobarray, NextPageToken: token}, nil
+	page := server.LimitToPage(pageToken, Blobarray)
+	return &pb.ListNVMeSubsystemsResponse{NvMeSubsystems: page.List, NextPageToken: page.NextToken}, nil
 }
 
 // GetNVMeSubsystem gets NVMe Subsystems
@@ -360,14 +354,18 @@ func (s *Server) UpdateNVMeController(_ context.Context, in *pb.UpdateNVMeContro
 // ListNVMeControllers lists NVMe controllers
 func (s *Server) ListNVMeControllers(_ context.Context, in *pb.ListNVMeControllersRequest) (*pb.ListNVMeControllersResponse, error) {
 	log.Printf("Received from client: %v", in.Parent)
+	pageToken, perr := s.Pagination.PageToken(in.PageSize, in.PageToken)
+	if perr != nil {
+		log.Printf("error: %v", perr)
+		return nil, perr
+	}
 	Blobarray := []*pb.NVMeController{}
 	for _, controller := range s.Nvme.Controllers {
 		Blobarray = append(Blobarray, controller)
 	}
 	sortNVMeControllers(Blobarray)
-	token := uuid.New().String()
-	s.Pagination[token] = int(in.PageSize)
-	return &pb.ListNVMeControllersResponse{NvMeControllers: Blobarray, NextPageToken: token}, nil
+	page := server.LimitToPage(pageToken, Blobarray)
+	return &pb.ListNVMeControllersResponse{NvMeControllers: page.List, NextPageToken: page.NextToken}, nil
 }
 
 // GetNVMeController gets an NVMe controller
@@ -501,7 +499,7 @@ func (s *Server) UpdateNVMeNamespace(_ context.Context, in *pb.UpdateNVMeNamespa
 // ListNVMeNamespaces lists NVMe namespaces
 func (s *Server) ListNVMeNamespaces(_ context.Context, in *pb.ListNVMeNamespacesRequest) (*pb.ListNVMeNamespacesResponse, error) {
 	log.Printf("ListNVMeNamespaces: Received from client: %v", in)
-	size, offset, perr := server.ExtractPagination(in.PageSize, in.PageToken, s.Pagination)
+	pageToken, perr := s.Pagination.PageToken(in.PageSize, in.PageToken)
 	if perr != nil {
 		log.Printf("error: %v", perr)
 		return nil, perr
@@ -523,18 +521,10 @@ func (s *Server) ListNVMeNamespaces(_ context.Context, in *pb.ListNVMeNamespaces
 		return nil, err
 	}
 	log.Printf("Received from SPDK: %v", result)
-	token := ""
 	Blobarray := []*pb.NVMeNamespace{}
 	for i := range result {
 		rr := &result[i]
 		if rr.Nqn == nqn || nqn == "" {
-			log.Printf("Limiting result len(%d) to [%d:%d]", len(result), offset, size)
-			hasMoreElements := false
-			rr.Namespaces, hasMoreElements = server.LimitPagination(rr.Namespaces, offset, size)
-			if hasMoreElements {
-				token = uuid.New().String()
-				s.Pagination[token] = offset + size
-			}
 			for j := range rr.Namespaces {
 				r := &rr.Namespaces[j]
 				Blobarray = append(Blobarray, &pb.NVMeNamespace{Spec: &pb.NVMeNamespaceSpec{HostNsid: int32(r.Nsid)}})
@@ -543,7 +533,8 @@ func (s *Server) ListNVMeNamespaces(_ context.Context, in *pb.ListNVMeNamespaces
 	}
 	if len(Blobarray) > 0 {
 		sortNVMeNamespaces(Blobarray)
-		return &pb.ListNVMeNamespacesResponse{NvMeNamespaces: Blobarray, NextPageToken: token}, nil
+		page := server.LimitToPage(pageToken, Blobarray)
+		return &pb.ListNVMeNamespacesResponse{NvMeNamespaces: page.List, NextPageToken: page.NextToken}, nil
 	}
 
 	msg := fmt.Sprintf("Could not find any namespaces for NQN: %s", nqn)

pkg/frontend/scsi.go

@@ -29,6 +29,12 @@ func sortScsiControllers(controllers []*pb.VirtioScsiController) {
 	})
 }
 
+func sortScsiLuns(controllers []*pb.VirtioScsiLun) {
+	sort.Slice(controllers, func(i int, j int) bool {
+		return controllers[i].Id.Value < controllers[j].Id.Value
+	})
+}
+
 // CreateVirtioScsiController creates a Virtio SCSI controller
 func (s *Server) CreateVirtioScsiController(_ context.Context, in *pb.CreateVirtioScsiControllerRequest) (*pb.VirtioScsiController, error) {
 	log.Printf("CreateVirtioScsiController: Received from client: %v", in)
@@ -108,7 +114,7 @@ func (s *Server) UpdateVirtioScsiController(_ context.Context, in *pb.UpdateVirt
 // ListVirtioScsiControllers lists Virtio SCSI controllers
 func (s *Server) ListVirtioScsiControllers(_ context.Context, in *pb.ListVirtioScsiControllersRequest) (*pb.ListVirtioScsiControllersResponse, error) {
 	log.Printf("ListVirtioScsiControllers: Received from client: %v", in)
-	size, offset, perr := server.ExtractPagination(in.PageSize, in.PageToken, s.Pagination)
+	pageToken, perr := s.Pagination.PageToken(in.PageSize, in.PageToken)
 	if perr != nil {
 		log.Printf("error: %v", perr)
 		return nil, perr
@@ -120,20 +126,14 @@ func (s *Server) ListVirtioScsiControllers(_ context.Context, in *pb.ListVirtioS
 		return nil, err
 	}
 	log.Printf("Received from SPDK: %v", result)
-	token := ""
-	log.Printf("Limiting result len(%d) to [%d:%d]", len(result), offset, size)
-	result, hasMoreElements := server.LimitPagination(result, offset, size)
-	if hasMoreElements {
-		token = uuid.New().String()
-		s.Pagination[token] = offset + size
-	}
 	Blobarray := make([]*pb.VirtioScsiController, len(result))
 	for i := range result {
 		r := &result[i]
 		Blobarray[i] = &pb.VirtioScsiController{Id: &pc.ObjectKey{Value: r.Ctrlr}}
 	}
 	sortScsiControllers(Blobarray)
-	return &pb.ListVirtioScsiControllersResponse{VirtioScsiControllers: Blobarray, NextPageToken: token}, nil
+	page := server.LimitToPage(pageToken, Blobarray)
+	return &pb.ListVirtioScsiControllersResponse{VirtioScsiControllers: page.List, NextPageToken: page.NextToken}, nil
 }
 
 // GetVirtioScsiController gets a Virtio SCSI controller
@@ -249,7 +249,7 @@ func (s *Server) UpdateVirtioScsiLun(_ context.Context, in *pb.UpdateVirtioScsiL
 // ListVirtioScsiLuns lists Virtio SCSI LUNs
 func (s *Server) ListVirtioScsiLuns(_ context.Context, in *pb.ListVirtioScsiLunsRequest) (*pb.ListVirtioScsiLunsResponse, error) {
 	log.Printf("ListVirtioScsiLuns: Received from client: %v", in)
-	size, offset, perr := server.ExtractPagination(in.PageSize, in.PageToken, s.Pagination)
+	pageToken, perr := s.Pagination.PageToken(in.PageSize, in.PageToken)
 	if perr != nil {
 		log.Printf("error: %v", perr)
 		return nil, perr
@@ -261,19 +261,14 @@ func (s *Server) ListVirtioScsiLuns(_ context.Context, in *pb.ListVirtioScsiLuns
 		return nil, err
 	}
 	log.Printf("Received from SPDK: %v", result)
-	token := ""
-	log.Printf("Limiting result len(%d) to [%d:%d]", len(result), offset, size)
-	result, hasMoreElements := server.LimitPagination(result, offset, size)
-	if hasMoreElements {
-		token = uuid.New().String()
-		s.Pagination[token] = offset + size
-	}
 	Blobarray := make([]*pb.VirtioScsiLun, len(result))
 	for i := range result {
 		r := &result[i]
 		Blobarray[i] = &pb.VirtioScsiLun{VolumeId: &pc.ObjectKey{Value: r.Ctrlr}}
 	}
-	return &pb.ListVirtioScsiLunsResponse{VirtioScsiLuns: Blobarray, NextPageToken: token}, nil
+	sortScsiLuns(Blobarray)
+	page := server.LimitToPage(pageToken, Blobarray)
+	return &pb.ListVirtioScsiLunsResponse{VirtioScsiLuns: page.List, NextPageToken: page.NextToken}, nil
 }
 
 // GetVirtioScsiLun gets a Virtio SCSI LUN