github.com/slspeek/camlistore_namedsearch@v0.0.0-20140519202248-ed6f70f7721a/pkg/index/enumstat.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 index
    18  
    19  import (
    20  	"fmt"
    21  	"strconv"
    22  	"strings"
    23  
    24  	"camlistore.org/pkg/blob"
    25  	"camlistore.org/pkg/context"
    26  	"camlistore.org/pkg/sorted"
    27  )
    28  
    29  func (ix *Index) EnumerateBlobs(ctx *context.Context, dest chan<- blob.SizedRef, after string, limit int) (err error) {
    30  	defer close(dest)
    31  	it := ix.s.Find("have:"+after, "have~")
    32  	defer func() {
    33  		closeErr := it.Close()
    34  		if err == nil {
    35  			err = closeErr
    36  		}
    37  	}()
    38  
    39  	n := int(0)
    40  	for n < limit && it.Next() {
    41  		k := it.Key()
    42  		if k <= after {
    43  			continue
    44  		}
    45  		if !strings.HasPrefix(k, "have:") {
    46  			break
    47  		}
    48  		n++
    49  		br, ok := blob.Parse(k[len("have:"):])
    50  		size, err := strconv.ParseUint(it.Value(), 10, 32)
    51  		if ok && err == nil {
    52  			select {
    53  			case dest <- blob.SizedRef{br, uint32(size)}:
    54  			case <-ctx.Done():
    55  				return context.ErrCanceled
    56  			}
    57  		}
    58  	}
    59  	return nil
    60  }
    61  
    62  func (ix *Index) StatBlobs(dest chan<- blob.SizedRef, blobs []blob.Ref) error {
    63  	for _, br := range blobs {
    64  		key := "have:" + br.String()
    65  		v, err := ix.s.Get(key)
    66  		if err == sorted.ErrNotFound {
    67  			continue
    68  		}
    69  		if err != nil {
    70  			return fmt.Errorf("error looking up key %q: %v", key, err)
    71  		}
    72  		size, err := strconv.ParseInt(v, 10, 64)
    73  		if err != nil {
    74  			return fmt.Errorf("invalid size for key %q = %q", key, v)
    75  		}
    76  		dest <- blob.SizedRef{br, uint32(size)}
    77  	}
    78  	return nil
    79  }