coreapi: dag: Batching interface

License: MIT
Signed-off-by: Łukasz Magiera <magik6k@gmail.com>

core/coreapi/dag.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"io"
+	"sync"
 
 	gopath "path"
 
@@ -17,34 +18,25 @@ import (
 
 type DagAPI CoreAPI
 
+type dagBatch struct {
+	api   *DagAPI
+	toPut []ipld.Node
+
+	lk sync.Mutex
+}
+
 // Put inserts data using specified format and input encoding. Unless used with
 // `WithCodes` or `WithHash`, the defaults "dag-cbor" and "sha256" are used.
 // Returns the path of the inserted data.
 func (api *DagAPI) Put(ctx context.Context, src io.Reader, opts ...caopts.DagPutOption) (coreiface.ResolvedPath, error) {
-	settings, err := caopts.DagPutOptions(opts...)
-	if err != nil {
-		return nil, err
-	}
+	nd, err := getNode(src, opts...)
 
-	codec, ok := cid.CodecToStr[settings.Codec]
-	if !ok {
-		return nil, fmt.Errorf("invalid codec %d", settings.Codec)
-	}
-
-	nds, err := coredag.ParseInputs(settings.InputEnc, codec, src, settings.MhType, settings.MhLength)
+	err = api.node.DAG.Add(ctx, nd)
 	if err != nil {
 		return nil, err
 	}
-	if len(nds) == 0 {
-		return nil, fmt.Errorf("no node returned from ParseInputs")
-	}
 
-	err = api.node.DAG.Add(ctx, nds[0])
-	if err != nil {
-		return nil, err
-	}
-
-	return coreiface.IpldPath(nds[0].Cid()), nil
+	return coreiface.IpldPath(nd.Cid()), nil
 }
 
 // Get resolves `path` using Unixfs resolver, returns the resolved Node.
@@ -75,6 +67,58 @@ func (api *DagAPI) Tree(ctx context.Context, p coreiface.Path, opts ...caopts.Da
 	return out, nil
 }
 
+func (api *DagAPI) Batch(ctx context.Context) coreiface.DagBatch {
+	return &dagBatch{api: api}
+}
+
+func (b *dagBatch) Put(ctx context.Context, src io.Reader, opts ...caopts.DagPutOption) (coreiface.ResolvedPath, error) {
+	nd, err := getNode(src, opts...)
+	if err != nil {
+		return nil, err
+	}
+
+	b.lk.Lock()
+	b.toPut = append(b.toPut, nd)
+	b.lk.Unlock()
+
+	return coreiface.IpldPath(nd.Cid()), nil
+}
+
+func (b *dagBatch) Commit(ctx context.Context) error {
+	b.lk.Lock()
+	defer b.lk.Unlock()
+	defer func() {
+		b.toPut = nil
+	}()
+
+	return b.api.node.DAG.AddMany(ctx, b.toPut)
+}
+
+func getNode(src io.Reader, opts ...caopts.DagPutOption) (ipld.Node, error) {
+	settings, err := caopts.DagPutOptions(opts...)
+	if err != nil {
+		return nil, err
+	}
+
+	codec, ok := cid.CodecToStr[settings.Codec]
+	if !ok {
+		return nil, fmt.Errorf("invalid codec %d", settings.Codec)
+	}
+
+	nds, err := coredag.ParseInputs(settings.InputEnc, codec, src, settings.MhType, settings.MhLength)
+	if err != nil {
+		return nil, err
+	}
+	if len(nds) == 0 {
+		return nil, fmt.Errorf("no node returned from ParseInputs")
+	}
+	if len(nds) != 1 {
+		return nil, fmt.Errorf("got more that one node from ParseInputs")
+	}
+
+	return nds[0], nil
+}
+
 func (api *DagAPI) core() coreiface.CoreAPI {
 	return (*CoreAPI)(api)
 }

core/coreapi/interface/dag.go

@@ -4,21 +4,36 @@ import (
 	"context"
 	"io"
 
-	options "github.com/ipfs/go-ipfs/core/coreapi/interface/options"
+	"github.com/ipfs/go-ipfs/core/coreapi/interface/options"
 
 	ipld "gx/ipfs/QmZtNq8dArGfnpCZfx2pUNY7UcjGhVp5qqwQ4hH6mpTMRQ/go-ipld-format"
 )
 
-// DagAPI specifies the interface to IPLD
-type DagAPI interface {
+// DagOps groups operations that can be batched together
+type DagOps interface {
 	// Put inserts data using specified format and input encoding.
 	// Unless used with WithCodec or WithHash, the defaults "dag-cbor" and
 	// "sha256" are used.
 	Put(ctx context.Context, src io.Reader, opts ...options.DagPutOption) (ResolvedPath, error)
+}
+
+// DagBatch is the batching version of DagAPI. All implementations of DagBatch
+// should be threadsafe
+type DagBatch interface {
+	DagOps
+
+	Commit(ctx context.Context) error
+}
+
+// DagAPI specifies the interface to IPLD
+type DagAPI interface {
+	DagOps
 
 	// Get attempts to resolve and get the node specified by the path
 	Get(ctx context.Context, path Path) (ipld.Node, error)
 
 	// Tree returns list of paths within a node specified by the path.
 	Tree(ctx context.Context, path Path, opts ...options.DagTreeOption) ([]Path, error)
+
+	Batch(ctx context.Context) DagBatch
 }