142-Fabric開發(四) 基於Fabirc1.4.3編寫你的第一個應用

寫在前面（到到底什麼是Fabric？）

在第一節的最後，我粗略地說了說到底什麼是Fabirc。在這裡，我得再問自己一遍。到底什麼是Fabirc？
我這個人比較喜歡望文生義，見文知意，顧名思義。。。找Gu爸問問，給如下結果：

具體是什麼意思，我們暫且按下不表。來看看，我們的另外一個角兒，Hyperledger（超級賬本）。對，我們這裡講Fabric確切的說只是Hyperledger下的一個專案而已。中文官網描述如下：

到這裡，我們應該對Hyperledger Fabirc（以下簡稱Fabric）有了進一步的認識，他本質就是一項分散式賬本技術，結合上文的翻譯，Fabric就是一個分散式賬本技術框架。至於對該技術的分析，我們後續文章會進行連載，再問億遍什麼是Fabirc。這裡，我們先來編寫一個應用，看看他到底在做什麼，能做什麼吧。

基於Fabric編寫第一個應用程式

我們寫這個程式要幹什麼呢？
最基本的功能就是要給使用者提供查詢賬本（包含特定記錄）和更新賬本（新增記錄）。

而這個程式會基於javascript，通過Node.js SDK與賬本所在的網路進行互動。

Hyperledger中文文件給出了以下步驟，我們可以照貓畫虎來試試。（畢竟是入門文章，刪除線覆蓋部分可以先不看）

啟動一個Hyperledger Fabric區塊鏈測試網路。
在我們的網路中，我們需要一些最基本的元件來查詢和更新賬本。這些元件<peer節點、ordering節點以及證書管理>是我們網路的基礎。而CLI容器則用來發送一些管理命令。有個簡單的指令碼將下載並啟動這個測試網路。
學習應用程式中所用到的智慧合約例子的引數。
~~智慧合約包含的各種功能讓我們可以用多種方式和賬本進行互動。如，我們可以讀取整體的資料或者某一部分詳盡的資料。~~
開發能夠查詢以及更新記錄的應用程式。
~~我們提供兩個程式例子 —— 一個用於查詢賬本，另一個使用者更新賬本。我們的程式將使用SDK APIs來和網路進行互動，並最終呼叫這些功能。~~

好了，廢話不多說，正文開始

1、首先，啟動測試網路

上節我們已經下載了的fabric中已經包含了fabric-samples，執行下面操作

cd fabric-samples/fabcar ; ls

可以看到fabcar樣例包含的指令碼和程式程式碼

2、下載並解壓Hyperledger Fabric Docker images

下載映象

./startFabric.sh

執行過程如下:

halfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/fabcar$ ./startFabric.sh Stopping for channel 'mychannel' with CLI timeout of '10' seconds and CLI delay of '3' secondsproceeding ...WARNING: The BYFN_CA2_PRIVATE_KEY variable is not set. Defaulting to a blank string.WARNING: The BYFN_CA1_PRIVATE_KEY variable is not set. Defaulting to a blank string.Stopping cli                    ... doneStopping peer0.org2.example.com ... doneStopping orderer.example.com    ... doneStopping peer1.org2.example.com ... doneStopping peer1.org1.example.com ... doneStopping peer0.org1.example.com ... doneRemoving cli                    ... doneRemoving peer0.org2.example.com ... doneRemoving orderer.example.com    ... doneRemoving peer1.org2.example.com ... doneRemoving peer1.org1.example.com ... doneRemoving peer0.org1.example.com ... doneRemoving network net_byfnRemoving volume net_peer0.org3.example.comWARNING: Volume net_peer0.org3.example.com not found.Removing volume net_peer1.org3.example.comWARNING: Volume net_peer1.org3.example.com not found.Removing volume net_orderer2.example.comWARNING: Volume net_orderer2.example.com not found.Removing volume net_orderer.example.comRemoving volume net_peer0.org2.example.comRemoving volume net_peer0.org1.example.comRemoving volume net_peer1.org1.example.comRemoving volume net_peer1.org2.example.comRemoving volume net_orderer5.example.comWARNING: Volume net_orderer5.example.com not found.Removing volume net_orderer4.example.comWARNING: Volume net_orderer4.example.com not found.Removing volume net_orderer3.example.comWARNING: Volume net_orderer3.example.com not found.57da35e620757727893af4a0b1fab6da4a8cUntagged: dev-peer1.org2.example.com-mycc-1.0-26c2ef32838554aac4f7ad6f100aca865e87959c9a126e86d764c8d01f8346ab:latestDeleted: sha256:a361bdbae52fd3897a325606f2c3f1d7a23fb737d8b12f987a0d927f1e7ddfb2Deleted: sha256:41880d8787311ec41d2162219382b44ce4c656513c4d8cc5ea8bdb6a1379c51fDeleted: sha256:d8c907db9d43ebefb2f1c76d89ad11546ca186b55bd3f1cb2ed9ec99eed2d26eDeleted: sha256:2c4c8355d0acd14eff6fa105568de64b27a9b5cce3523c31a57a32a1afa28891Untagged: dev-peer0.org1.example.com-mycc-1.0-384f11f484b9302df90b453200cfb25174305fce8f53f4e94d45ee3b6cab0ce9:latestDeleted: sha256:3425e36582cdcb3d0da871f71976622ab353b9c8a512e0555a73b790bec1ee22Deleted: sha256:e98f3c309f14bc6306be86a137e11166ee83abdd96ecac89698e658f225be899Deleted: sha256:cbfe5ddde265d8294e77bdde9314e9bb6a384dae9085922ecab85cb6ceae4547Deleted: sha256:e962aafc8595469a2b3ec55f05e3e042b0bda3dca52f1e600d0f7311c21f4732Untagged: dev-peer0.org2.example.com-mycc-1.0-15b571b3ce849066b7ec74497da3b27e54e0df1345daff3951b94245ce09c42b:latestDeleted: sha256:714e8f05a4ffaf0f544cc710e865022e8c513e95c060a55eacb7a2b818540c64Deleted: sha256:0a43b52a03c8d649886ad62bb923494c3fc9c7badf65977d816bd7994ecebb0cDeleted: sha256:2d4758a2f6ea8c70a747bf7b4beb31b199b05f2b7f09ddef3a097e2844151f41Deleted: sha256:1fae417e6afb0a2e4178d2b43ab673997d66cad0cb55ced26b07e092b5ec8642Starting for channel 'mychannel' with CLI timeout of '10' seconds and CLI delay of '3' seconds and using database 'couchdb'proceeding ..../byfn.sh: line 124: configtxlator: command not foundLOCAL_VERSION=DOCKER_IMAGE_VERSION=1.4.3=================== WARNING ===================  Local fabric binaries and docker images are    out of  sync. This may cause problems.       ===============================================/home/halfape/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/first-network/../bin/cryptogen############################################################### Generate certificates using cryptogen tool ###################################################################+ cryptogen generate --config=./crypto-config.yamlorg1.example.comorg2.example.com+ res=0+ set +xGenerate CCP files for Org1 and Org2/home/halfape/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/first-network/../bin/configtxgen###################################################################  Generating Orderer Genesis block ########################################################################CONSENSUS_TYPE=solo+ '[' solo == solo ']'+ configtxgen -profile TwoOrgsOrdererGenesis -channelID byfn-sys-channel -outputBlock ./channel-artifacts/genesis.block2020-09-25 10:38:25.424 CST [common.tools.configtxgen] main -> INFO 001 Loading configuration2020-09-25 10:38:25.638 CST [common.tools.configtxgen.localconfig] completeInitialization -> INFO 002 orderer type: solo2020-09-25 10:38:25.638 CST [common.tools.configtxgen.localconfig] Load -> INFO 003 Loaded configuration: /home/halfape/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/first-network/configtx.yaml2020-09-25 10:38:25.768 CST [common.tools.configtxgen.localconfig] completeInitialization -> INFO 004 orderer type: solo2020-09-25 10:38:25.768 CST [common.tools.configtxgen.localconfig] LoadTopLevel -> INFO 005 Loaded configuration: /home/halfape/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/first-network/configtx.yaml2020-09-25 10:38:25.770 CST [common.tools.configtxgen] doOutputBlock -> INFO 006 Generating genesis block2020-09-25 10:38:25.771 CST [common.tools.configtxgen] doOutputBlock -> INFO 007 Writing genesis block+ res=0+ set +x#################################################################### Generating channel configuration transaction 'channel.tx' ####################################################################+ configtxgen -profile TwoOrgsChannel -outputCreateChannelTx ./channel-artifacts/channel.tx -channelID mychannel2020-09-25 10:38:25.815 CST [common.tools.configtxgen] main -> INFO 001 Loading configuration2020-09-25 10:38:25.953 CST [common.tools.configtxgen.localconfig] Load -> INFO 002 Loaded configuration: /home/halfape/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/first-network/configtx.yaml2020-09-25 10:38:26.139 CST [common.tools.configtxgen.localconfig] completeInitialization -> INFO 003 orderer type: solo2020-09-25 10:38:26.139 CST [common.tools.configtxgen.localconfig] LoadTopLevel -> INFO 004 Loaded configuration: /home/halfape/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/first-network/configtx.yaml2020-09-25 10:38:26.139 CST [common.tools.configtxgen] doOutputChannelCreateTx -> INFO 005 Generating new channel configtx2020-09-25 10:38:26.141 CST [common.tools.configtxgen] doOutputChannelCreateTx -> INFO 006 Writing new channel tx+ res=0+ set +x########################################################################    Generating anchor peer update for Org1MSP   ###########################################################################+ configtxgen -profile TwoOrgsChannel -outputAnchorPeersUpdate ./channel-artifacts/Org1MSPanchors.tx -channelID mychannel -asOrg Org1MSP2020-09-25 10:38:26.188 CST [common.tools.configtxgen] main -> INFO 001 Loading configuration2020-09-25 10:38:26.322 CST [common.tools.configtxgen.localconfig] Load -> INFO 002 Loaded configuration: /home/halfape/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/first-network/configtx.yaml2020-09-25 10:38:26.451 CST [common.tools.configtxgen.localconfig] completeInitialization -> INFO 003 orderer type: solo2020-09-25 10:38:26.451 CST [common.tools.configtxgen.localconfig] LoadTopLevel -> INFO 004 Loaded configuration: /home/halfape/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/first-network/configtx.yaml2020-09-25 10:38:26.451 CST [common.tools.configtxgen] doOutputAnchorPeersUpdate -> INFO 005 Generating anchor peer update2020-09-25 10:38:26.452 CST [common.tools.configtxgen] doOutputAnchorPeersUpdate -> INFO 006 Writing anchor peer update+ res=0+ set +x########################################################################    Generating anchor peer update for Org2MSP   ###########################################################################+ configtxgen -profile TwoOrgsChannel -outputAnchorPeersUpdate ./channel-artifacts/Org2MSPanchors.tx -channelID mychannel -asOrg Org2MSP2020-09-25 10:38:26.491 CST [common.tools.configtxgen] main -> INFO 001 Loading configuration2020-09-25 10:38:26.632 CST [common.tools.configtxgen.localconfig] Load -> INFO 002 Loaded configuration: /home/halfape/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/first-network/configtx.yaml2020-09-25 10:38:26.767 CST [common.tools.configtxgen.localconfig] completeInitialization -> INFO 003 orderer type: solo2020-09-25 10:38:26.767 CST [common.tools.configtxgen.localconfig] LoadTopLevel -> INFO 004 Loaded configuration: /home/halfape/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/first-network/configtx.yaml2020-09-25 10:38:26.767 CST [common.tools.configtxgen] doOutputAnchorPeersUpdate -> INFO 005 Generating anchor peer update2020-09-25 10:38:26.767 CST [common.tools.configtxgen] doOutputAnchorPeersUpdate -> INFO 006 Writing anchor peer update+ res=0+ set +xCreating network "net_byfn" with the default driverCreating volume "net_peer0.org2.example.com" with default driverCreating volume "net_peer1.org2.example.com" with default driverCreating volume "net_peer1.org1.example.com" with default driverCreating volume "net_peer0.org1.example.com" with default driverCreating volume "net_orderer.example.com" with default driverCreating couchdb1 ... Creating ca_peerOrg1 ... Creating ca_peerOrg2 ... Creating couchdb2 ... Creating couchdb3 ... Creating orderer.example.com ... Creating couchdb0 ... Creating couchdb1Creating ca_peerOrg1Creating orderer.example.comCreating ca_peerOrg2Creating couchdb0Creating couchdb3Creating couchdb3 ... doneCreating couchdb1 ... doneCreating peer0.org2.example.com ... Creating peer1.org2.example.com ... Creating peer1.org1.example.com ... Creating peer0.org2.example.comCreating peer0.org1.example.comCreating peer1.org2.example.comCreating peer1.org1.example.com ... doneCreating cli ... Creating cli ... doneCONTAINER ID        IMAGE                               COMMAND                  CREATED             STATUS                  PORTS                                        NAMES25db1f49bd0d        hyperledger/fabric-tools:latest     "/bin/bash"              3 seconds ago       Up Less than a second                                                cliffa08fe12f45        hyperledger/fabric-peer:latest      "peer node start"        10 seconds ago      Up 3 seconds            0.0.0.0:10051->10051/tcp                     peer1.org2.example.comdb986456e3f1        hyperledger/fabric-peer:latest      "peer node start"        10 seconds ago      Up 3 seconds            0.0.0.0:8051->8051/tcp                       peer1.org1.example.com6b58e2f9f0fd        hyperledger/fabric-peer:latest      "peer node start"        10 seconds ago      Up 3 seconds            0.0.0.0:7051->7051/tcp                       peer0.org1.example.com99f1a6861f29        hyperledger/fabric-peer:latest      "peer node start"        10 seconds ago      Up 5 seconds            0.0.0.0:9051->9051/tcp                       peer0.org2.example.com083ad91dc52d        hyperledger/fabric-couchdb          "tini -- /docker-ent…"   16 seconds ago      Up 10 seconds           4369/tcp, 9100/tcp, 0.0.0.0:7984->5984/tcp   couchdb2278bd416710a        hyperledger/fabric-couchdb          "tini -- /docker-ent…"   16 seconds ago      Up 10 seconds           4369/tcp, 9100/tcp, 0.0.0.0:5984->5984/tcp   couchdb0e027cdca24ae        hyperledger/fabric-ca:latest        "sh -c 'fabric-ca-se…"   16 seconds ago      Up 10 seconds           7054/tcp, 0.0.0.0:8054->8054/tcp             ca_peerOrg240ba0e78f3a2        hyperledger/fabric-couchdb          "tini -- /docker-ent…"   16 seconds ago      Up 10 seconds           4369/tcp, 9100/tcp, 0.0.0.0:8984->5984/tcp   couchdb3302ff3534644        hyperledger/fabric-orderer:latest   "orderer"                16 seconds ago      Up 10 seconds           0.0.0.0:7050->7050/tcp                       orderer.example.com6875e13d9078        hyperledger/fabric-ca:latest        "sh -c 'fabric-ca-se…"   16 seconds ago      Up 10 seconds           0.0.0.0:7054->7054/tcp                       ca_peerOrg1dfa539ffb0b5        hyperledger/fabric-couchdb          "tini -- /docker-ent…"   16 seconds ago      Up 10 seconds           4369/tcp, 9100/tcp, 0.0.0.0:6984->5984/tcp   couchdb1 ____    _____      _      ____    _____ / ___|  |_   _|    / \    |  _ \  |_   _|\___ \    | |     / _ \   | |_) |   | |   ___) |   | |    / ___ \  |  _ <    | |  |____/    |_|   /_/   \_\ |_| \_\   |_|  Build your first network (BYFN) end-to-end testChannel name : mychannelCreating channel...+ peer channel create -o orderer.example.com:7050 -c mychannel -f ./channel-artifacts/channel.tx --tls true --cafile /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem+ res=0+ set +x2020-09-25 02:38:45.449 UTC [channelCmd] InitCmdFactory -> INFO 001 Endorser and orderer connections initialized2020-09-25 02:38:45.677 UTC [cli.common] readBlock -> INFO 002 Got status: &{NOT_FOUND}2020-09-25 02:38:45.679 UTC [channelCmd] InitCmdFactory -> INFO 003 Endorser and orderer connections initialized2020-09-25 02:38:45.916 UTC [cli.common] readBlock -> INFO 004 Received block: 0===================== Channel 'mychannel' created ===================== Having all peers join the channel...+ peer channel join -b mychannel.block+ res=1+ set +xError: error getting endorser client for channel: endorser client failed to connect to peer0.org1.example.com:7051: failed to create new connection: connection error: desc = "transport: error while dialing: dial tcp 172.20.0.11:7051: connect: connection refused"peer0.org1 failed to join the channel, Retry after 3 seconds+ peer channel join -b mychannel.block+ res=1+ set +xError: error getting endorser client for channel: endorser client failed to connect to peer0.org1.example.com:7051: failed to create new connection: connection error: desc = "transport: error while dialing: dial tcp 172.20.0.11:7051: connect: connection refused"peer0.org1 failed to join the channel, Retry after 3 seconds+ peer channel join -b mychannel.block+ res=0+ set +x2020-09-25 02:38:52.604 UTC [channelCmd] InitCmdFactory -> INFO 001 Endorser and orderer connections initialized2020-09-25 02:38:53.046 UTC [channelCmd] executeJoin -> INFO 002 Successfully submitted proposal to join channel===================== peer0.org1 joined channel 'mychannel' ===================== + peer channel join -b mychannel.block+ res=0+ set +x2020-09-25 02:38:56.141 UTC [channelCmd] InitCmdFactory -> INFO 001 Endorser and orderer connections initialized2020-09-25 02:38:56.324 UTC [channelCmd] executeJoin -> INFO 002 Successfully submitted proposal to join channel===================== peer1.org1 joined channel 'mychannel' ===================== + peer channel join -b mychannel.block+ res=0+ set +x2020-09-25 02:38:59.461 UTC [channelCmd] InitCmdFactory -> INFO 001 Endorser and orderer connections initialized2020-09-25 02:38:59.669 UTC [channelCmd] executeJoin -> INFO 002 Successfully submitted proposal to join channel===================== peer0.org2 joined channel 'mychannel' ===================== + peer channel join -b mychannel.block+ res=0+ set +x2020-09-25 02:39:02.781 UTC [channelCmd] InitCmdFactory -> INFO 001 Endorser and orderer connections initialized2020-09-25 02:39:03.110 UTC [channelCmd] executeJoin -> INFO 002 Successfully submitted proposal to join channel===================== peer1.org2 joined channel 'mychannel' ===================== Updating anchor peers for org1...+ peer channel update -o orderer.example.com:7050 -c mychannel -f ./channel-artifacts/Org1MSPanchors.tx --tls true --cafile /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem+ res=0+ set +x2020-09-25 02:39:06.210 UTC [channelCmd] InitCmdFactory -> INFO 001 Endorser and orderer connections initialized2020-09-25 02:39:06.392 UTC [channelCmd] update -> INFO 002 Successfully submitted channel update===================== Anchor peers updated for org 'Org1MSP' on channel 'mychannel' ===================== Updating anchor peers for org2...+ peer channel update -o orderer.example.com:7050 -c mychannel -f ./channel-artifacts/Org2MSPanchors.tx --tls true --cafile /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem+ res=0+ set +x2020-09-25 02:39:09.469 UTC [channelCmd] InitCmdFactory -> INFO 001 Endorser and orderer connections initialized2020-09-25 02:39:09.496 UTC [channelCmd] update -> INFO 002 Successfully submitted channel update===================== Anchor peers updated for org 'Org2MSP' on channel 'mychannel' ===================== ========= All GOOD, BYFN execution completed ===========  _____   _   _   ____   | ____| | \ | | |  _ \  |  _|   |  \| | | | | | | |___  | |\  | | |_| | |_____| |_| \_| |____/  + echo 'Installing smart contract on peer0.org1.example.com'Installing smart contract on peer0.org1.example.com+ docker exec -e CORE_PEER_LOCALMSPID=Org1MSP -e CORE_PEER_ADDRESS=peer0.org1.example.com:7051 -e CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/users/[email protected]/msp -e CORE_PEER_TLS_ROOTCERT_FILE=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/peers/peer0.org1.example.com/tls/ca.crt cli peer chaincode install -n fabcar -v 1.0 -p github.com/chaincode/fabcar/go -l golang2020-09-25 02:39:13.810 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 001 Using default escc2020-09-25 02:39:13.810 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 002 Using default vscc2020-09-25 02:39:16.156 UTC [chaincodeCmd] install -> INFO 003 Installed remotely response:<status:200 payload:"OK" > + echo 'Installing smart contract on peer1.org1.example.com'Installing smart contract on peer1.org1.example.com+ docker exec -e CORE_PEER_LOCALMSPID=Org1MSP -e CORE_PEER_ADDRESS=peer1.org1.example.com:8051 -e CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/users/[email protected]/msp -e CORE_PEER_TLS_ROOTCERT_FILE=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/peers/peer0.org1.example.com/tls/ca.crt cli peer chaincode install -n fabcar -v 1.0 -p github.com/chaincode/fabcar/go -l golang2020-09-25 02:39:16.543 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 001 Using default escc2020-09-25 02:39:16.543 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 002 Using default vscc2020-09-25 02:39:16.793 UTC [chaincodeCmd] install -> INFO 003 Installed remotely response:<status:200 payload:"OK" > + echo 'Installing smart contract on peer0.org2.example.com'Installing smart contract on peer0.org2.example.com+ docker exec -e CORE_PEER_LOCALMSPID=Org2MSP -e CORE_PEER_ADDRESS=peer0.org2.example.com:9051 -e CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org2.example.com/users/[email protected]/msp -e CORE_PEER_TLS_ROOTCERT_FILE=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org2.example.com/peers/peer0.org2.example.com/tls/ca.crt cli peer chaincode install -n fabcar -v 1.0 -p github.com/chaincode/fabcar/go -l golang2020-09-25 02:39:17.188 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 001 Using default escc2020-09-25 02:39:17.188 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 002 Using default vscc2020-09-25 02:39:17.458 UTC [chaincodeCmd] install -> INFO 003 Installed remotely response:<status:200 payload:"OK" > + echo 'Installing smart contract on peer1.org2.example.com'Installing smart contract on peer1.org2.example.com+ docker exec -e CORE_PEER_LOCALMSPID=Org2MSP -e CORE_PEER_ADDRESS=peer1.org2.example.com:10051 -e CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org2.example.com/users/[email protected]/msp -e CORE_PEER_TLS_ROOTCERT_FILE=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org2.example.com/peers/peer0.org2.example.com/tls/ca.crt cli peer chaincode install -n fabcar -v 1.0 -p github.com/chaincode/fabcar/go -l golang2020-09-25 02:39:17.774 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 001 Using default escc2020-09-25 02:39:17.774 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 002 Using default vscc2020-09-25 02:39:18.016 UTC [chaincodeCmd] install -> INFO 003 Installed remotely response:<status:200 payload:"OK" > + echo 'Instantiating smart contract on mychannel'Instantiating smart contract on mychannel+ docker exec -e CORE_PEER_LOCALMSPID=Org1MSP -e CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/users/[email protected]/msp cli peer chaincode instantiate -o orderer.example.com:7050 -C mychannel -n fabcar -l golang -v 1.0 -c '{"Args":[]}' -P 'AND('\''Org1MSP.member'\'','\''Org2MSP.member'\'')' --tls --cafile /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem --peerAddresses peer0.org1.example.com:7051 --tlsRootCertFiles /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/peers/peer0.org1.example.com/tls/ca.crt2020-09-25 02:39:18.397 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 001 Using default escc2020-09-25 02:39:18.398 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 002 Using default vscc+ echo 'Waiting for instantiation request to be committed ...'Waiting for instantiation request to be committed ...+ sleep 10+ echo 'Submitting initLedger transaction to smart contract on mychannel'Submitting initLedger transaction to smart contract on mychannel+ echo 'The transaction is sent to all of the peers so that chaincode is built before receiving the following requests'The transaction is sent to all of the peers so that chaincode is built before receiving the following requests+ docker exec -e CORE_PEER_LOCALMSPID=Org1MSP -e CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/users/[email protected]/msp cli peer chaincode invoke -o orderer.example.com:7050 -C mychannel -n fabcar -c '{"function":"initLedger","Args":[]}' --waitForEvent --tls --cafile /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem --peerAddresses peer0.org1.example.com:7051 --peerAddresses peer1.org1.example.com:8051 --peerAddresses peer0.org2.example.com:9051 --peerAddresses peer1.org2.example.com:10051 --tlsRootCertFiles /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/peers/peer0.org1.example.com/tls/ca.crt --tlsRootCertFiles /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/peers/peer0.org1.example.com/tls/ca.crt --tlsRootCertFiles /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org2.example.com/peers/peer0.org2.example.com/tls/ca.crt --tlsRootCertFiles /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org2.example.com/peers/peer0.org2.example.com/tls/ca.crt2020-09-25 02:41:52.030 UTC [chaincodeCmd] ClientWait -> INFO 002 txid [526e4e9e4df22f304b49bbe0e93b8cdd0b523afc273d7a5277f8ca7e0087e7b2] committed with status (VALID) at peer1.org1.example.com:80512020-09-25 02:41:51.979 UTC [chaincodeCmd] ClientWait -> INFO 003 txid [526e4e9e4df22f304b49bbe0e93b8cdd0b523afc273d7a5277f8ca7e0087e7b2] committed with status (VALID) at peer1.org2.example.com:100512020-09-25 02:41:51.983 UTC [chaincodeCmd] ClientWait -> INFO 001 txid [526e4e9e4df22f304b49bbe0e93b8cdd0b523afc273d7a5277f8ca7e0087e7b2] committed with status (VALID) at peer0.org2.example.com:90512020-09-25 02:41:52.061 UTC [chaincodeCmd] ClientWait -> INFO 004 txid [526e4e9e4df22f304b49bbe0e93b8cdd0b523afc273d7a5277f8ca7e0087e7b2] committed with status (VALID) at peer0.org1.example.com:70512020-09-25 02:41:52.100 UTC [chaincodeCmd] chaincodeInvokeOrQuery -> INFO 005 Chaincode invoke successful. result: status:200 + set +xTotal setup execution time : 225 secs ...Next, use the FabCar applications to interact with the deployed FabCar contract.The FabCar applications are available in multiple programming languages.Follow the instructions for the programming language of your choice:JavaScript:  Start by changing into the "javascript" directory:    cd javascript  Next, install all required packages:    npm install  Then run the following applications to enroll the admin user, and register a new user  called user1 which will be used by the other applications to interact with the deployed  FabCar contract:    node enrollAdmin    node registerUser  You can run the invoke application as follows. By default, the invoke application will  create a new car, but you can update the application to submit other transactions:    node invoke  You can run the query application as follows. By default, the query application will  return all cars, but you can update the application to evaluate other transactions:    node queryTypeScript:  Start by changing into the "typescript" directory:    cd typescript  Next, install all required packages:    npm install  Next, compile the TypeScript code into JavaScript:    npm run build  Then run the following applications to enroll the admin user, and register a new user  called user1 which will be used by the other applications to interact with the deployed  FabCar contract:    node dist/enrollAdmin    node dist/registerUser  You can run the invoke application as follows. By default, the invoke application will  create a new car, but you can update the application to submit other transactions:    node dist/invoke  You can run the query application as follows. By default, the query application will  return all cars, but you can update the application to evaluate other transactions:    node dist/queryJava:  Start by changing into the "java" directory:    cd java  Then, install dependencies and run the test using:    mvn test  The test will invoke the sample client app which perform the following:    - Enroll admin and user1 and import them into the wallet (if they don't already exist there)    - Submit a transaction to create a new car    - Evaluate a transaction (query) to return details of this car    - Submit a transaction to change the owner of this car    - Evaluate a transaction (query) to return the updated details of this carhalfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/fabcar$

分析上面的日誌，我們主要做了哪些事情呢？

停止了上次開啟的網路
啟動peer節點、Ordering節點、證書頒發機構以及CLI容器】
建立一個通道，並將peer加入該通道
將智慧合約（即鏈碼）安裝到peer節點的檔案系統上，並在通道上例項化該鏈碼；例項化會啟動鏈碼容器
呼叫initLedger功能來向通道賬本寫入10個不同的汽車

最後，還想我們展示瞭如何來跑這個應用程式，以javascript為例，那我們按照命令來試試吧

3、查詢賬本

查詢是指如何從賬本中讀取資料。您可以查詢單個或者多個鍵的值，如果賬本是以類似於JSON這樣的資料儲存格式寫入的，則可以執行更復雜的搜尋（如查詢包含某些關鍵字的所有資產）。

1.具體操作，在`javascript`中執行以下命令

halfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/fabcar/javascript$ npm installnpm WARN [email protected] No repository field.up to date in 4.15s4 packages are looking for funding  run `npm fund` for detailshalfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/fabcar/javascript$ node enrollAdminWallet path: /home/halfape/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/fabcar/javascript/walletAn identity for the admin user "admin" already exists in the wallethalfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/fabcar/javascript$ node registerUserWallet path: /home/halfape/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/fabcar/javascript/walletSuccessfully registered and enrolled admin user "user1" and imported it into the wallethalfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/fabcar/javascript$ node invokeWallet path: /home/halfape/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/fabcar/javascript/walletTransaction has been submittedhalfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/fabcar/javascript$ node queryWallet path: /home/halfape/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/fabcar/javascript/walletTransaction has been evaluated, result is: [{"colour":"brown","make":"Holden","model":"Barina","owner":"Shotaro"}}]

我們可以看到
這裡有10輛車，一輛屬於Adriana的黑色Tesla Model S、一輛屬於Brad的紅色Ford Mustang、一輛屬於Pari的紫羅蘭色Fiat Punto等等。賬本是基於Key/Value 的，在這裡，關鍵字是從CAR0到CAR9。這一點特別重要。

2.程式碼分析

我們可以大佬query.js裡面的程式碼具體做了什麼。

const path = require('path');  const ccpPath = path.resolve(__dirname, '..', '..', 'first-network', 'connection-org1.json');async function main() {    try {        // Create a new file system based wallet for managing identities.        const walletPath = path.join(process.cwd(), 'wallet');        const wallet = new FileSystemWallet(walletPath);        console.log(`Wallet path: ${walletPath}`);        // Check to see if we've already enrolled the user.        const userExists = await wallet.exists('user1');        if (!userExists) {            console.log('An identity for the user "user1" does not exist in the wallet');            console.log('Run the registerUser.js application before retrying');            return;        }        // Create a new gateway for connecting to our peer node.        const gateway = new Gateway();        await gateway.connect(ccpPath, { wallet, identity: 'user1', discovery: { enabled: true, asLocalhost: true } });        // Get the network (channel) our contract is deployed to.        const network = await gateway.getNetwork('mychannel');        // Get the contract from the network.        const contract = network.getContract('fabcar');        // Evaluate the specified transaction.        // queryCar transaction - requires 1 argument, ex: ('queryCar', 'CAR4')        // queryAllCars transaction - requires no arguments, ex: ('queryAllCars')        const result = await contract.evaluateTransaction('queryAllCars');        console.log(`Transaction has been evaluated, result is: ${result.toString()}`);    } catch (error) {        console.error(`Failed to evaluate transaction: ${error}`);        process.exit(1);    }}main();

簡單分析：

會發現主要做了建立錢包，給錢包中新增使用者，獲取通道，獲取合約，呼叫合約函式`queryAllCars`的操作完成了查詢。

那我們這個查詢函式具體實現在哪呢？如下

halfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric$ lsbccsp          CODE_OF_CONDUCT.md  devenv         examples    gotools.mk   LICENSE   peer       release_notes    testingInfo.rst   unit-testCHANGELOG.md   common              discovery      Gopkg.lock  idemix       Makefile  protos     sampleconfig     test-pyramid.png  vendorci.properties  CONTRIBUTING.md     docker-env.mk  Gopkg.toml  images       msp       README.md  scripts          tokencmd            core                docs           gossip      integration  orderer   release    settings.gradle  tox.inihalfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric$ cd scripts/halfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts$ lsbootstrap.sh  check_deps.sh     check_spelling.sh        compile_protos.sh  generateHelpDocs.sh  goListFiles.sh  multiarch.sh             run-integration-tests.shchangelog.sh  check_license.sh  check_trailingspaces.sh  fabric-samples     golinter.sh          metrics_doc.sh  pull_build_artifacts.shhalfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts$ cd fabric-samples/halfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples$ lsbalance-transfer  bin        chaincode-docker-devmode  CODE_OF_CONDUCT.md  CONTRIBUTING.md  fabcar         high-throughput      Jenkinsfile  MAINTAINERS.md  README.mdbasic-network     chaincode  ci.properties             commercial-paper    docs             first-network  interest_rate_swaps  LICENSE      off_chain_data  scriptshalfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples$ cd chaincodehalfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/chaincode$ lsabac  chaincode_example02  fabcar  marbles02  marbles02_private  sacchalfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/chaincode$ cd fabcar/halfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/chaincode/fabcar$ lsgo  java  javascript  javascript-low-level  typescripthalfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/chaincode/fabcar$ cd javascripthalfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/chaincode/fabcar/javascript$ lsindex.js  lib  package.jsonhalfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/chaincode/fabcar/javascript$ cd lib/halfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/chaincode/fabcar/javascript/lib$ lsfabcar.jshalfape@halfape-VirtualBox:~/go/src/github.com/hyperledger/fabric/scripts/fabric-samples/chaincode/fabcar/javascript/lib$

開啟fabric.js,具體程式碼如下

/* * SPDX-License-Identifier: Apache-2.0 */'use strict';const { Contract } = require('fabric-contract-api');class FabCar extends Contract {    async initLedger(ctx) {        console.info('============= START : Initialize Ledger ===========');        const cars = [            {                color: 'blue',                make: 'Toyota',                model: 'Prius',                owner: 'Tomoko',            },            {                color: 'red',                make: 'Ford',                model: 'Mustang',                owner: 'Brad',            },            {                color: 'green',                make: 'Hyundai',                model: 'Tucson',                owner: 'Jin Soo',            },            {                color: 'yellow',                make: 'Volkswagen',                model: 'Passat',                owner: 'Max',            },            {                color: 'black',                make: 'Tesla',                model: 'S',                owner: 'Adriana',            },            {                color: 'purple',                make: 'Peugeot',                model: '205',                owner: 'Michel',            },            {                color: 'white',                make: 'Chery',                model: 'S22L',                owner: 'Aarav',            },            {                color: 'violet',                make: 'Fiat',                model: 'Punto',                owner: 'Pari',            },            {                color: 'indigo',                make: 'Tata',                model: 'Nano',                owner: 'Valeria',            },            {                color: 'brown',                make: 'Holden',                model: 'Barina',                owner: 'Shotaro',            },        ];        for (let i = 0; i < cars.length; i++) {            cars[i].docType = 'car';            await ctx.stub.putState('CAR' + i, Buffer.from(JSON.stringify(cars[i])));            console.info('Added <--> ', cars[i]);        }        console.info('============= END : Initialize Ledger ===========');    }    async queryCar(ctx, carNumber) {        const carAsBytes = await ctx.stub.getState(carNumber); // get the car from chaincode state        if (!carAsBytes || carAsBytes.length === 0) {            throw new Error(`${carNumber} does not exist`);        }        console.log(carAsBytes.toString());        return carAsBytes.toString();    }    async createCar(ctx, carNumber, make, model, color, owner) {        console.info('============= START : Create Car ===========');        const car = {            color,            docType: 'car',            make,            model,            owner,        };        await ctx.stub.putState(carNumber, Buffer.from(JSON.stringify(car)));        console.info('============= END : Create Car ===========');    }    async queryAllCars(ctx) {        const startKey = 'CAR0';        const endKey = 'CAR999';        const iterator = await ctx.stub.getStateByRange(startKey, endKey);        const allResults = [];        while (true) {            const res = await iterator.next();            if (res.value && res.value.value.toString()) {                console.log(res.value.value.toString('utf8'));                const Key = res.value.key;                let Record;                try {                    Record = JSON.parse(res.value.value.toString('utf8'));                } catch (err) {                    console.log(err);                    Record = res.value.value.toString('utf8');                }                allResults.push({ Key, Record });            }            if (res.done) {                console.log('end of data');                await iterator.close();                console.info(allResults);                return JSON.stringify(allResults);            }        }    }    async changeCarOwner(ctx, carNumber, newOwner) {        console.info('============= START : changeCarOwner ===========');        const carAsBytes = await ctx.stub.getState(carNumber); // get the car from chaincode state        if (!carAsBytes || carAsBytes.length === 0) {            throw new Error(`${carNumber} does not exist`);        }        const car = JSON.parse(carAsBytes.toString());        car.owner = newOwner;        await ctx.stub.putState(carNumber, Buffer.from(JSON.stringify(car)));        console.info('============= END : changeCarOwner ===========');    }}mdule.exports = FabCar;

會發現，除了我們的queryCar函式queryAllCars函式，還有createCar函式和changeCarOwner函式。另外還可以看到在初始化的時候出現了10輛汽車的原因。

在queryAllCars中有這麼一段

const startKey = 'CAR0';        const endKey = 'CAR999';        const iterator = await ctx.stub.getStateByRange(startKey, endKey);

該函式呼叫shim介面函式GetStateByRange來返回引數在startKey和endKey間的賬本資料。這兩個鍵值分別定義為CAR0和CAR999。因此，我們理論上可以建立1,000輛汽車（假設Keys都被正確使用），queryAllCars函式將會顯示出每一輛汽車的資訊。

既然看懂了程式碼，我們來做點小改動，回到剛才的query.js，編輯如下：

const result = await contract.evaluateTransaction('queryCar','CAR4');

然後再來執行，應當只查出CAR4的資訊，我們來看看吧

果然結果也是對的。因為車輛資訊是從0開始的，所以這裡是黑色特斯拉。

4、更新賬本

我們來看看另外一個獨立的用於交易的程式invoke.js,進行開啟

/* * SPDX-License-Identifier: Apache-2.0 */'use strict';const { FileSystemWallet, Gateway } = require('fabric-network');const path = require('path');const ccpPath = path.resolve(__dirname, '..', '..', 'first-network', 'connection-org1.json');const ccpPath = path.resolve(__dirname, '..', '..', 'first-network', 'connection-org1.json');async function main() {    try {        // Create a new file system based wallet for managing identities.        const walletPath = path.join(process.cwd(), 'wallet');        const wallet = new FileSystemWallet(walletPath);        console.log(`Wallet path: ${walletPath}`);        // Check to see if we've already enrolled the user.        const userExists = await wallet.exists('user1');        if (!userExists) {            console.log('An identity for the user "user1" does not exist in the wallet');            console.log('Run the registerUser.js application before retrying');            return;        }        // Create a new gateway for connecting to our peer node.        const gateway = new Gateway();        await gateway.connect(ccpPath, { wallet, identity: 'user1', discovery: { enabled: true, asLocalhost: true } });        // Get the network (channel) our contract is deployed to.        const network = await gateway.getNetwork('mychannel');        // Get the contract from the network.        const contract = network.getContract('fabcar');        // Submit the specified transaction.        // createCar transaction - requires 5 argument, ex: ('createCar', 'CAR12', 'Honda', 'Accord', 'Black', 'Tom')        // changeCarOwner transaction - requires 2 args , ex: ('changeCarOwner', 'CAR10', 'Dave')        await contract.submitTransaction('createCar', 'CAR12', 'Honda', 'Accord', 'Black', 'Tom');        console.log('Transaction has been submitted');        // Disconnect from the gateway.        await gateway.disconnect();    } catch (error) {        console.error(`Failed to submit transaction: ${error}`);        process.exit(1);    }}main();

簡單分析會發現主要做了建立錢包，給錢包中新增使用者，呼叫合約函式`createCar`的操作完成了提交交易的操作。

另外我們做一個簡單的修改，然後執行node invoke.js，會顯示交易已經被提交。

await contract.submitTransaction('createCar', 'CAR10', 'Aodi', 'Accord', 'Blue', 'halfape');

此時，我們在vim query.js，修改為查詢CAR10資訊，執行node query.js，則會顯示以下資訊。

還有一個chanegCarOwner，大家可以自己試試哈。

Fabric互動應用程式原理分析

下圖演示了一個應用程式如何在鏈碼（智慧合約）中呼叫不同功能。

從上圖以及上面的例子就可以看出：應用程式通過智慧合約（在Fabric中叫做鏈碼）從區塊鏈上獲取資訊或者更新資訊。

在來看一張圖，展示了應用程式是如何我們的Fabric網路進行互動的。

相信跟著我一步步除錯到這裡，你已經對Fabric又有了新的認識,對區塊鏈又有了新的認識。Say Goodbye~

參考文章：

https://blog.csdn.net/dalang1010/article/details/78940200
https://cn.hyperledger.org/
https://hyperledgercn.github.io/hyperledgerDocs/build_network_zh/

寫在最後

最後，還是得感謝眾多前輩所給的案例以及親身踩過的坑，我才得以成功測試這個小應用。如果你覺得這篇文章對你有所幫助，關注微信公眾號半路猿，拉你進我們的學習交流群，一起學習，一同成長。