github.com/kchristidis/fabric@v1.0.4-0.20171028114726-837acd08cde1/core/deliverservice/requester.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 deliverclient
    18  
    19  import (
    20  	"math"
    21  
    22  	"github.com/hyperledger/fabric/common/localmsp"
    23  	"github.com/hyperledger/fabric/core/deliverservice/blocksprovider"
    24  	"github.com/hyperledger/fabric/protos/common"
    25  	"github.com/hyperledger/fabric/protos/orderer"
    26  	"github.com/hyperledger/fabric/protos/utils"
    27  )
    28  
    29  type blocksRequester struct {
    30  	chainID string
    31  	client  blocksprovider.BlocksDeliverer
    32  }
    33  
    34  func (b *blocksRequester) RequestBlocks(ledgerInfoProvider blocksprovider.LedgerInfo) error {
    35  	height, err := ledgerInfoProvider.LedgerHeight()
    36  	if err != nil {
    37  		logger.Errorf("Can't get legder height for channel %s from committer [%s]", b.chainID, err)
    38  		return err
    39  	}
    40  
    41  	if height > 0 {
    42  		logger.Debugf("Starting deliver with block [%d] for channel %s", height, b.chainID)
    43  		if err := b.seekLatestFromCommitter(height); err != nil {
    44  			return err
    45  		}
    46  	} else {
    47  		logger.Debugf("Starting deliver with olders block for channel %s", b.chainID)
    48  		if err := b.seekOldest(); err != nil {
    49  			return err
    50  		}
    51  	}
    52  
    53  	return nil
    54  }
    55  
    56  func (b *blocksRequester) seekOldest() error {
    57  	seekInfo := &orderer.SeekInfo{
    58  		Start:    &orderer.SeekPosition{Type: &orderer.SeekPosition_Oldest{Oldest: &orderer.SeekOldest{}}},
    59  		Stop:     &orderer.SeekPosition{Type: &orderer.SeekPosition_Specified{Specified: &orderer.SeekSpecified{Number: math.MaxUint64}}},
    60  		Behavior: orderer.SeekInfo_BLOCK_UNTIL_READY,
    61  	}
    62  
    63  	//TODO- epoch and msgVersion may need to be obtained for nowfollowing usage in orderer/configupdate/configupdate.go
    64  	msgVersion := int32(0)
    65  	epoch := uint64(0)
    66  	env, err := utils.CreateSignedEnvelope(common.HeaderType_CONFIG_UPDATE, b.chainID, localmsp.NewSigner(), seekInfo, msgVersion, epoch)
    67  	if err != nil {
    68  		return err
    69  	}
    70  	return b.client.Send(env)
    71  }
    72  
    73  func (b *blocksRequester) seekLatestFromCommitter(height uint64) error {
    74  	seekInfo := &orderer.SeekInfo{
    75  		Start:    &orderer.SeekPosition{Type: &orderer.SeekPosition_Specified{Specified: &orderer.SeekSpecified{Number: height}}},
    76  		Stop:     &orderer.SeekPosition{Type: &orderer.SeekPosition_Specified{Specified: &orderer.SeekSpecified{Number: math.MaxUint64}}},
    77  		Behavior: orderer.SeekInfo_BLOCK_UNTIL_READY,
    78  	}
    79  
    80  	//TODO- epoch and msgVersion may need to be obtained for nowfollowing usage in orderer/configupdate/configupdate.go
    81  	msgVersion := int32(0)
    82  	epoch := uint64(0)
    83  	env, err := utils.CreateSignedEnvelope(common.HeaderType_CONFIG_UPDATE, b.chainID, localmsp.NewSigner(), seekInfo, msgVersion, epoch)
    84  	if err != nil {
    85  		return err
    86  	}
    87  	return b.client.Send(env)
    88  }