github.com/leonlxy/hyperledger@v1.0.0-alpha.0.20170427033203-34922035d248/peer/channel/deliverclient.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 channel 18 19 import ( 20 "fmt" 21 "math" 22 23 "github.com/hyperledger/fabric/common/localmsp" 24 "github.com/hyperledger/fabric/protos/common" 25 ab "github.com/hyperledger/fabric/protos/orderer" 26 "github.com/hyperledger/fabric/protos/utils" 27 ) 28 29 type deliverClientIntf interface { 30 getBlock() (*common.Block, error) 31 } 32 33 type deliverClient struct { 34 client ab.AtomicBroadcast_DeliverClient 35 chainID string 36 } 37 38 func newDeliverClient(client ab.AtomicBroadcast_DeliverClient, chainID string) *deliverClient { 39 return &deliverClient{client: client, chainID: chainID} 40 } 41 42 func seekHelper(chainID string, start *ab.SeekPosition) *common.Envelope { 43 seekInfo := &ab.SeekInfo{ 44 Start: &ab.SeekPosition{Type: &ab.SeekPosition_Oldest{Oldest: &ab.SeekOldest{}}}, 45 Stop: &ab.SeekPosition{Type: &ab.SeekPosition_Specified{Specified: &ab.SeekSpecified{Number: math.MaxUint64}}}, 46 Behavior: ab.SeekInfo_BLOCK_UNTIL_READY, 47 } 48 49 //TODO- epoch and msgVersion may need to be obtained for nowfollowing usage in orderer/configupdate/configupdate.go 50 msgVersion := int32(0) 51 epoch := uint64(0) 52 env, err := utils.CreateSignedEnvelope(common.HeaderType_CONFIG_UPDATE, chainID, localmsp.NewSigner(), seekInfo, msgVersion, epoch) 53 if err != nil { 54 fmt.Printf("Error signing envelope %s\n", err) 55 return nil 56 } 57 return env 58 } 59 60 func (r *deliverClient) seekOldest() error { 61 return r.client.Send(seekHelper(r.chainID, &ab.SeekPosition{Type: &ab.SeekPosition_Oldest{Oldest: &ab.SeekOldest{}}})) 62 } 63 64 func (r *deliverClient) seekNewest() error { 65 return r.client.Send(seekHelper(r.chainID, &ab.SeekPosition{Type: &ab.SeekPosition_Newest{Newest: &ab.SeekNewest{}}})) 66 } 67 68 func (r *deliverClient) seek(blockNumber uint64) error { 69 return r.client.Send(seekHelper(r.chainID, &ab.SeekPosition{Type: &ab.SeekPosition_Specified{Specified: &ab.SeekSpecified{Number: blockNumber}}})) 70 } 71 72 func (r *deliverClient) readBlock() (*common.Block, error) { 73 for { 74 msg, err := r.client.Recv() 75 if err != nil { 76 fmt.Println("Error receiving:", err) 77 return nil, err 78 } 79 80 switch t := msg.Type.(type) { 81 case *ab.DeliverResponse_Status: 82 fmt.Println("Got status ", t) 83 continue 84 case *ab.DeliverResponse_Block: 85 fmt.Println("Received block: ", t.Block) 86 return t.Block, nil 87 } 88 } 89 } 90 91 func (r *deliverClient) getBlock() (*common.Block, error) { 92 err := r.seek(0) 93 if err != nil { 94 fmt.Println("Received error:", err) 95 return nil, err 96 } 97 98 b, err := r.readBlock() 99 if err != nil { 100 return nil, err 101 } 102 103 return b, nil 104 }