use one cb and use goroutines to call fileRef

Author: sunilmhta

cmd/gateway/zcn/gateway-zcn.go

@@ -11,6 +11,7 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/0chain/gosdk/zboxcore/sdk"
@@ -548,58 +549,77 @@ func (zob *zcnObjects) PutMultipleObjects(
 	}
 	operationRequests := make([]sdk.OperationRequest, total)
 	objectInfo := make([]minio.ObjectInfo, total)
-	cbs := make([]*statusCB, total)
+	cb := &statusCB{
+		doneCh: make(chan struct{}, 1),
+		errCh:  make(chan error, 1),
+	}
+
+	var wg sync.WaitGroup
+	errCh := make(chan error, total)
 	for i := 0; i < total; i++ {
-		var ref *sdk.ORef
-		ref, err := getSingleRegularRef(zob.alloc, remotePaths[i])
-		if err != nil {
-			if !isPathNoExistError(err) {
-				return nil, []error{err}
+		wg.Add(1)
+		go func(idx int) {
+			defer wg.Done()
+			var ref *sdk.ORef
+			ref, err := getSingleRegularRef(zob.alloc, remotePaths[idx])
+			if err != nil {
+				if !isPathNoExistError(err) {
+					errCh <- err
+					return
+				}
 			}
-		}
 
-		var isUpdate bool
-		if ref != nil {
-			isUpdate = true
-		}
+			var isUpdate bool
+			if ref != nil {
+				isUpdate = true
+			}
 
-		contentType := opts[i].UserDefined["content-type"]
-		if contentType == "" {
-			contentType = "application/octet-stream"
-		}
+			contentType := opts[idx].UserDefined["content-type"]
+			if contentType == "" {
+				contentType = "application/octet-stream"
+			}
 
-		_, fileName := filepath.Split(remotePaths[i])
-		fileMeta := sdk.FileMeta{
-			Path:       "",
-			RemotePath: remotePaths[i],
-			ActualSize: r[i].Size(),
-			MimeType:   contentType,
-			RemoteName: fileName,
-		}
+			_, fileName := filepath.Split(remotePaths[idx])
+			fileMeta := sdk.FileMeta{
+				Path:       "",
+				RemotePath: remotePaths[idx],
+				ActualSize: r[idx].Size(),
+				MimeType:   contentType,
+				RemoteName: fileName,
+			}
 
-		cbs[i] = &statusCB{
-			doneCh: make(chan struct{}, 1),
-			errCh:  make(chan error, 1),
-		}
-		options := []sdk.ChunkedUploadOption{
-			sdk.WithStatusCallback(cbs[i]),
-			sdk.WithEncrypt(false),
-		}
-		operationRequests[i] = sdk.OperationRequest{
-			FileMeta:      fileMeta,
-			FileReader:    newMinioReader(r[i]),
-			OperationType: constants.FileOperationInsert,
-			Opts:          options,
-		}
-		if isUpdate {
-			operationRequests[i].OperationType = constants.FileOperationUpdate
-		}
-		objectInfo[i] = minio.ObjectInfo{
-			Bucket:  bucket,
-			Name:    objects[i],
-			Size:    r[i].Size(),
-			ModTime: time.Now(),
-		}
+			options := []sdk.ChunkedUploadOption{
+				sdk.WithStatusCallback(cb),
+				sdk.WithEncrypt(false),
+			}
+			operationRequests[idx] = sdk.OperationRequest{
+				FileMeta:      fileMeta,
+				FileReader:    newMinioReader(r[idx]),
+				OperationType: constants.FileOperationInsert,
+				Opts:          options,
+			}
+			if isUpdate {
+				operationRequests[idx].OperationType = constants.FileOperationUpdate
+			}
+			objectInfo[idx] = minio.ObjectInfo{
+				Bucket:  bucket,
+				Name:    objects[idx],
+				Size:    r[idx].Size(),
+				ModTime: time.Now(),
+			}
+		}(i)
+	}
+	wg.Wait()
+	close(errCh)
+
+	var errs []error
+	for err := range errCh {
+		errs = append(errs, err)
+	}
+
+	if errs != nil && len(errs) > 0 {
+		logger.Error("error while getting file ref and creating operationRequests.")
+		return nil, errs
 	}
 
 	errn := zob.alloc.DoMultiOperation(operationRequests)
@@ -608,16 +628,13 @@ func (zob *zcnObjects) PutMultipleObjects(
 		return nil, []error{errn}
 	}
 
-	var errs []error
-	for i, cb := range cbs {
-		select {
-		case <-cb.doneCh:
-		case err := <-cb.errCh:
-			errs = append(errs, fmt.Errorf("error for object %s: %v", objects[i], err)) // store the error in case of unsuccessful upload for ith object
-		}
+	select {
+	case <-cb.doneCh:
+	case err := <-cb.errCh:
+		return nil, []error{err}
 	}
 
-	return objectInfo, errs
+	return objectInfo, nil
 }
 func (zob *zcnObjects) CopyObject(ctx context.Context, srcBucket, srcObject, destBucket, destObject string, srcInfo minio.ObjectInfo, srcOpts, dstOpts minio.ObjectOptions) (objInfo minio.ObjectInfo, err error) {
 	var srcRemotePath, dstRemotePath string