1	/*
     2	Copyright 2014 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 mongo
    18	
    19	import (
    20		"context"
    21		"io"
    22	
    23		"perkeep.org/pkg/blob"
    24	
    25		"gopkg.in/mgo.v2"
    26	)
    27	
    28	const (
    29		// This error code is returned by mongo when a unique key violation occurs when inserting
    30		// See: http://www.mongodb.org/about/contributors/error-codes/
    31		mgoUniqueKeyErr = 11000
    32	)
    33	
    34	func (m *mongoStorage) ReceiveBlob(ctx context.Context, ref blob.Ref, source io.Reader) (blob.SizedRef, error) {
    35		blobData, err := io.ReadAll(source)
    36		if err != nil {
    37			return blob.SizedRef{}, err
    38		}
    39	
    40		b := blobDoc{Key: ref.String(), Blob: blobData, Size: uint32(len(blobData))}
    41	
    42		if err = m.c.Insert(b); err != nil {
    43			// Unique key violation?
    44			// Then the blob already exists, no need to throw an error
    45			if mongoErr, isMongoErr := err.(*mgo.LastError); isMongoErr && mongoErr.Code == mgoUniqueKeyErr {
    46				return blob.SizedRef{Ref: ref, Size: b.Size}, nil
    47			}
    48			return blob.SizedRef{}, err
    49		}
    50		return blob.SizedRef{Ref: ref, Size: b.Size}, nil
    51	}