github.com/kchristidis/fabric@v1.0.4-0.20171028114726-837acd08cde1/orderer/ledger/file/factory.go (about)

     1  /*
     2  Copyright IBM Corp. 2017 All Rights Reserved.
     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 fileledger
    18  
    19  import (
    20  	"sync"
    21  
    22  	"github.com/hyperledger/fabric/common/ledger/blkstorage"
    23  	"github.com/hyperledger/fabric/common/ledger/blkstorage/fsblkstorage"
    24  	"github.com/hyperledger/fabric/orderer/ledger"
    25  )
    26  
    27  type fileLedgerFactory struct {
    28  	blkstorageProvider blkstorage.BlockStoreProvider
    29  	ledgers            map[string]ledger.ReadWriter
    30  	mutex              sync.Mutex
    31  }
    32  
    33  // GetOrCreate gets an existing ledger (if it exists) or creates it if it does not
    34  func (flf *fileLedgerFactory) GetOrCreate(chainID string) (ledger.ReadWriter, error) {
    35  	flf.mutex.Lock()
    36  	defer flf.mutex.Unlock()
    37  
    38  	key := chainID
    39  	// check cache
    40  	ledger, ok := flf.ledgers[key]
    41  	if ok {
    42  		return ledger, nil
    43  	}
    44  	// open fresh
    45  	blockStore, err := flf.blkstorageProvider.OpenBlockStore(key)
    46  	if err != nil {
    47  		return nil, err
    48  	}
    49  	ledger = &fileLedger{blockStore: blockStore, signal: make(chan struct{})}
    50  	flf.ledgers[key] = ledger
    51  	return ledger, nil
    52  }
    53  
    54  // ChainIDs returns the chain IDs the factory is aware of
    55  func (flf *fileLedgerFactory) ChainIDs() []string {
    56  	chainIDs, err := flf.blkstorageProvider.List()
    57  	if err != nil {
    58  		logger.Panic(err)
    59  	}
    60  	return chainIDs
    61  }
    62  
    63  // Close releases all resources acquired by the factory
    64  func (flf *fileLedgerFactory) Close() {
    65  	flf.blkstorageProvider.Close()
    66  }
    67  
    68  // New creates a new ledger factory
    69  func New(directory string) ledger.Factory {
    70  	return &fileLedgerFactory{
    71  		blkstorageProvider: fsblkstorage.NewProvider(
    72  			fsblkstorage.NewConf(directory, -1),
    73  			&blkstorage.IndexConfig{
    74  				AttrsToIndex: []blkstorage.IndexableAttr{blkstorage.IndexableAttrBlockNum}},
    75  		),
    76  		ledgers: make(map[string]ledger.ReadWriter),
    77  	}
    78  }