github.com/slspeek/camlistore_namedsearch@v0.0.0-20140519202248-ed6f70f7721a/pkg/blobserver/s3/stat.go (about)

     1  /*
     2  Copyright 2011 Google Inc.
     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  	"fmt"
    21  	"os"
    22  
    23  	"camlistore.org/pkg/blob"
    24  	"camlistore.org/pkg/syncutil"
    25  )
    26  
    27  var statGate = syncutil.NewGate(20) // arbitrary
    28  
    29  func (sto *s3Storage) StatBlobs(dest chan<- blob.SizedRef, blobs []blob.Ref) (err error) {
    30  	if faultStat.FailErr(&err) {
    31  		return
    32  	}
    33  	var wg syncutil.Group
    34  	for _, br := range blobs {
    35  		br := br
    36  		statGate.Start()
    37  		wg.Go(func() error {
    38  			defer statGate.Done()
    39  
    40  			size, err := sto.s3Client.Stat(br.String(), sto.bucket)
    41  			if err == nil {
    42  				dest <- blob.SizedRef{Ref: br, Size: uint32(size)}
    43  				return nil
    44  			}
    45  			if err == os.ErrNotExist {
    46  				return nil
    47  			}
    48  			return fmt.Errorf("error statting %v: %v", br, err)
    49  		})
    50  	}
    51  	return wg.Err()
    52  }