[#1129] policer: Pull required EC chunks

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

pkg/services/object/get/remote_getter.go

@@ -0,0 +1,55 @@
+package getsvc
+
+import (
+	"context"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/core/client"
+	netmapCore "git.frostfs.info/TrueCloudLab/frostfs-node/pkg/core/netmap"
+	netmapSDK "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/netmap"
+	objectSDK "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object"
+	oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
+)
+
+type RemoteGetPrm struct {
+	Address oid.Address
+	Node    netmapSDK.NodeInfo
+}
+
+type RemoteGetter struct {
+	s  remoteStorageConstructor
+	es epochSource
+	ks keyStorage
+}
+
+func (g *RemoteGetter) Get(ctx context.Context, prm RemoteGetPrm) (*objectSDK.Object, error) {
+	var nodeInfo client.NodeInfo
+	if err := client.NodeInfoFromRawNetmapElement(&nodeInfo, netmapCore.Node(prm.Node)); err != nil {
+		return nil, err
+	}
+	rs, err := g.s.Get(nodeInfo)
+	if err != nil {
+		return nil, err
+	}
+	epoch, err := g.es.Epoch()
+	if err != nil {
+		return nil, err
+	}
+	key, err := g.ks.GetKey(nil)
+	if err != nil {
+		return nil, err
+	}
+	r := RemoteRequestParams{
+		Epoch:      epoch,
+		TTL:        1,
+		PrivateKey: key,
+	}
+	return rs.Get(ctx, prm.Address, r)
+}
+
+func NewRemoteGetter(cc clientConstructor, es epochSource, ks keyStorage) *RemoteGetter {
+	return &RemoteGetter{
+		s:  &multiclientRemoteStorageConstructor{clientConstructor: cc},
+		es: es,
+		ks: ks,
+	}
+}