1	/*
     2	Copyright 2011 The Perkeep Authors
     3	
     4	Licensed under the Apache License, Version 2.0 (the "License");
     5	you may not use this file except in compliance with the License.
     6	You may obtain a copy of the License at
     7	
     8	     http://www.apache.org/licenses/LICENSE-2.0
     9	
    10	Unless required by applicable law or agreed to in writing, software
    11	distributed under the License is distributed on an "AS IS" BASIS,
    12	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13	See the License for the specific language governing permissions and
    14	limitations under the License.
    15	*/
    16	
    17	package s3
    18	
    19	import (
    20		"context"
    21		"fmt"
    22	
    23		"github.com/aws/aws-sdk-go/aws"
    24		"github.com/aws/aws-sdk-go/service/s3"
    25		"perkeep.org/pkg/blob"
    26		"perkeep.org/pkg/blobserver"
    27	
    28		"go4.org/syncutil"
    29	)
    30	
    31	var statGate = syncutil.NewGate(20) // arbitrary
    32	
    33	func (sto *s3Storage) StatBlobs(ctx context.Context, blobs []blob.Ref, fn func(blob.SizedRef) error) (err error) {
    34		if faultStat.FailErr(&err) {
    35			return
    36		}
    37	
    38		return blobserver.StatBlobsParallelHelper(ctx, blobs, fn, statGate, func(br blob.Ref) (sb blob.SizedRef, err error) {
    39			resp, err := sto.client.HeadObjectWithContext(ctx, &s3.HeadObjectInput{
    40				Bucket: &sto.bucket,
    41				Key:    aws.String(sto.dirPrefix + br.String()),
    42			})
    43			if err == nil {
    44				return blob.SizedRef{Ref: br, Size: uint32(*resp.ContentLength)}, nil
    45			}
    46			if isNotFound(err) {
    47				return sb, nil
    48			}
    49			return sb, fmt.Errorf("error statting %v: %v", br, err)
    50		})
    51	}