fix(coreapi/add): close the fake repo used when adding with hash-only

fixes ipfs#6744

core/coreapi/unixfs.go

@@ -3,7 +3,6 @@ package coreapi
 import (
 	"context"
 	"fmt"
-	"sync"
 
 	"github.com/ipfs/go-ipfs/core"
 
@@ -12,7 +11,6 @@ import (
 	blockservice "github.com/ipfs/go-blockservice"
 	cid "github.com/ipfs/go-cid"
 	cidutil "github.com/ipfs/go-cidutil"
-	filestore "github.com/ipfs/go-filestore"
 	bstore "github.com/ipfs/go-ipfs-blockstore"
 	files "github.com/ipfs/go-ipfs-files"
 	ipld "github.com/ipfs/go-ipld-format"
@@ -30,28 +28,6 @@ import (
 
 type UnixfsAPI CoreAPI
 
-var nilNode *core.IpfsNode
-var once sync.Once
-
-func getOrCreateNilNode() (*core.IpfsNode, error) {
-	once.Do(func() {
-		if nilNode != nil {
-			return
-		}
-		node, err := core.NewNode(context.Background(), &core.BuildCfg{
-			//TODO: need this to be true or all files
-			// hashed will be stored in memory!
-			NilRepo: true,
-		})
-		if err != nil {
-			panic(err)
-		}
-		nilNode = node
-	})
-
-	return nilNode, nil
-}
-
 // Add builds a merkledag node from a reader, adds it to the blockstore,
 // and returns the key representing that node.
 func (api *UnixfsAPI) Add(ctx context.Context, files files.Node, opts ...options.UnixfsAddOption) (path.Resolved, error) {
@@ -85,41 +61,24 @@ func (api *UnixfsAPI) Add(ctx context.Context, files files.Node, opts ...options
 	pinning := api.pinning
 
 	if settings.OnlyHash {
-		node, err := getOrCreateNilNode()
+		nilnode, err := core.NewNode(ctx, &core.BuildCfg{
+			//TODO: need this to be true or all files
+			// hashed will be stored in memory!
+			NilRepo: true,
+		})
 		if err != nil {
 			return nil, err
 		}
-		addblockstore = node.Blockstore
-		exch = node.Exchange
-		pinning = node.Pinning
+		defer nilnode.Close()
+		addblockstore = nilnode.Blockstore
+		exch = nilnode.Exchange
+		pinning = nilnode.Pinning
 	}
 
 	bserv := blockservice.New(addblockstore, exch) // hash security 001
 	dserv := dag.NewDAGService(bserv)
 
-	// add a sync call to the DagService
-	// this ensures that data written to the DagService is persisted to the underlying datastore
-	// TODO: propagate the Sync function from the datastore through the blockstore, blockservice and dagservice
-	var syncDserv *syncDagService
-	if settings.OnlyHash {
-		syncDserv = &syncDagService{
-			DAGService: dserv,
-			syncFn:     func() error { return nil },
-		}
-	} else {
-		syncDserv = &syncDagService{
-			DAGService: dserv,
-			syncFn: func() error {
-				ds := api.repo.Datastore()
-				if err := ds.Sync(bstore.BlockPrefix); err != nil {
-					return err
-				}
-				return ds.Sync(filestore.FilestorePrefix)
-			},
-		}
-	}
-
-	fileAdder, err := coreunix.NewAdder(ctx, pinning, addblockstore, syncDserv)
+	fileAdder, err := coreunix.NewAdder(ctx, pinning, addblockstore, dserv)
 	if err != nil {
 		return nil, err
 	}
@@ -295,13 +254,3 @@ func (api *UnixfsAPI) lsFromLinks(ctx context.Context, ndlinks []*ipld.Link, set
 func (api *UnixfsAPI) core() *CoreAPI {
 	return (*CoreAPI)(api)
 }
-
-// syncDagService is used by the Adder to ensure blocks get persisted to the underlying datastore
-type syncDagService struct {
-	ipld.DAGService
-	syncFn func() error
-}
-
-func (s *syncDagService) Sync() error {
-	return s.syncFn()
-}