当先锋百科网

首页 1 2 3 4 5 6 7

fabric-sdk-go编写

今天我们来学下fabric-sdk-go的编写

区块链是未来互联网的发展趋势，区块链是一个信息技术领域的术语。从本质上讲，它是一个共享数据库，存储于其中的数据或信息，具有“不可伪造”“全程留痕”“可以追溯”“公开透明”“集体维护”等特征。基于这些特征，区块链技术奠定了坚实的“信任”基础，创造了可靠的“合作”机制，具有广阔的运用前景。
所以学习区块链也能够为自己多一份保障。

  1. 首先，在区块链网络搭建完成以及链码编写完成并已经上链后，我们便可编写区块链应用层得编写了，编写应用层需要先编写sdk（请确保自己gopath里面有github.com/hyperledger/fabric-sdk-go包)依赖包我已经上传了 Golang依赖包 可以自行下载。那么我们首先编写应用层的sdk。在编写sdk前需要完成sdk的配置文件，尤其是要进行通信的Fabric组件的地址。我们将所有内容放入一个新的配置文件，Fabric SDK Go配置和我们的自定义参数中。
    使用如下命令创建config.yaml
 cd $GOPATH/src/github.com/chainHero/heroes-service && \
 vi config.yaml

以下是config.yaml的完整内容。

name: "heroes-service-network"
#
# Schema version of the content. Used by the SDK to apply the corresponding parsing rules.
#
version: 1.0.0

#
# The client section used by GO SDK.
#
client:

  # Which organization does this application instance belong to? The value must be the name of an org
  # defined under "organizations"
  organization: org1

  logging:
    level: info

  # Global configuration for peer, event service and orderer timeouts
  # if this this section is omitted, then default values will be used (same values as below)
#  peer:
#    timeout:
#      connection: 10s
#      response: 180s
#      discovery:
#        # Expiry period for discovery service greylist filter
#        # The channel client will greylist peers that are found to be offline
#        # to prevent re-selecting them in subsequent retries.
#        # This interval will define how long a peer is greylisted
#        greylistExpiry: 10s
#  eventService:
#    # Event service type (optional). If not specified then the type is automatically
#    # determined from channel capabilities.
#    type: (deliver|eventhub)
    # the below timeouts are commented out to use the default values that are found in
    # "pkg/fab/endpointconfig.go"
    # the client is free to override the default values by uncommenting and resetting
    # the values as they see fit in their config file
#    timeout:
#      connection: 15s
#      registrationResponse: 15s
#  orderer:
#    timeout:
#      connection: 15s
#      response: 15s
#  global:
#    timeout:
#      query: 180s
#      execute: 180s
#      resmgmt: 180s
#    cache:
#      connectionIdle: 30s
#      eventServiceIdle: 2m
#      channelConfig: 30m
#      channelMembership: 30s
#      discovery: 10s
#      selection: 10m

  # Root of the MSP directories with keys and certs.
  cryptoconfig:
    path: ${GOPATH}/src/github.com/chainHero/heroes-service/fixtures/crypto-config

  # Some SDKs support pluggable KV stores, the properties under "credentialStore"
  # are implementation specific
  credentialStore:
    path: /tmp/heroes-service-store

    # [Optional]. Specific to the CryptoSuite implementation used by GO SDK. Software-based implementations
    # requiring a key store. PKCS#11 based implementations does not.
    cryptoStore:
      path: /tmp/heroes-service-msp

   # BCCSP config for the client. Used by GO SDK.
  BCCSP:
    security:
     enabled: true
     default:
      provider: "SW"
     hashAlgorithm: "SHA2"
     softVerify: true
     level: 256

  tlsCerts:
    # [Optional]. Use system certificate pool when connecting to peers, orderers (for negotiating TLS) Default: false
    systemCertPool: false

    # [Optional]. Client key and cert for TLS handshake with peers and orderers
    client:
      keyfile:
      certfile:

#
# [Optional]. But most apps would have this section so that channel objects can be constructed
# based on the content below. If an app is creating channels, then it likely will not need this
# section.
#
channels:
  # name of the channel
  chainhero:
    # Required. list of orderers designated by the application to use for transactions on this
    # channel. This list can be a result of access control ("org1" can only access "ordererA"), or
    # operational decisions to share loads from applications among the orderers.  The values must
    # be "names" of orgs defined under "organizations/peers"
    # deprecated: not recommended, to override any orderer configuration items, entity matchers should be used.
    # orderers:
    #  - orderer.example.com

    # Required. list of peers from participating orgs
    peers:
      peer0.org1.hf.chainhero.io:
        # [Optional]. will this peer be sent transaction proposals for endorsement? The peer must
        # have the chaincode installed. The app can also use this property to decide which peers
        # to send the chaincode install request. Default: true
        endorsingPeer: true

        # [Optional]. will this peer be sent query proposals? The peer must have the chaincode
        # installed. The app can also use this property to decide which peers to send the
        # chaincode install request. Default: true
        chaincodeQuery: true

        # [Optional]. will this peer be sent query proposals that do not require chaincodes, like
        # queryBlock(), queryTransaction(), etc. Default: true
        ledgerQuery: true

        # [Optional]. will this peer be the target of the SDK's listener registration? All peers can
        # produce events but the app typically only needs to connect to one to listen to events.
        # Default: true
        eventSource: true

      peer1.org1.hf.chainhero.io:

    policies:
      #[Optional] options for retrieving channel configuration blocks
      queryChannelConfig:
        #[Optional] min number of success responses (from targets/peers)
        minResponses: 1
        #[Optional] channel config will be retrieved for these number of random targets
        maxTargets: 1
        #[Optional] retry options for query config block
        retryOpts:
          #[Optional] number of retry attempts
          attempts: 5
          #[Optional] the back off interval for the first retry attempt
          initialBackoff: 500ms
          #[Optional] the maximum back off interval for any retry attempt
          maxBackoff: 5s
          #[Optional] he factor by which the initial back off period is exponentially incremented
          backoffFactor: 2.0


#
# list of participating organizations in this network
#
organizations:
  org1:
    mspid: org1.hf.chainhero.io
    cryptoPath: peerOrganizations/org1.hf.chainhero.io/users/{userName}@org1.hf.chainhero.io/msp
    peers:
      - peer0.org1.hf.chainhero.io
      - peer1.org1.hf.chainhero.io

    # [Optional]. Certificate Authorities issue certificates for identification purposes in a Fabric based
    # network. Typically certificates provisioning is done in a separate process outside of the
    # runtime network. Fabric-CA is a special certificate authority that provides a REST APIs for
    # dynamic certificate management (enroll, revoke, re-enroll). The following section is only for
    # Fabric-CA servers.
    certificateAuthorities:
      - ca.org1.hf.chainhero.io

#
# List of orderers to send transaction and channel create/update requests to. For the time
# being only one orderer is needed. If more than one is defined, which one get used by the
# SDK is implementation specific. Consult each SDK's documentation for its handling of orderers.
#
orderers:
  orderer.hf.chainhero.io:
    url: localhost:7050

    # these are standard properties defined by the gRPC library
    # they will be passed in as-is to gRPC client constructor
    grpcOptions:
      ssl-target-name-override: orderer.hf.chainhero.io
      # These parameters should be set in coordination with the keepalive policy on the server,
      # as incompatible settings can result in closing of connection.
      # When duration of the 'keep-alive-time' is set to 0 or less the keep alive client parameters are disabled
      keep-alive-time: 0s
      keep-alive-timeout: 20s
      keep-alive-permit: false
      fail-fast: false
      # allow-insecure will be taken into consideration if address has no protocol defined, if true then grpc or else grpcs
      allow-insecure: false

    tlsCACerts:
      # Certificate location absolute path
      path: ${GOPATH}/src/github.com/chainHero/heroes-service/fixtures/crypto-config/ordererOrganizations/hf.chainhero.io/tlsca/tlsca.hf.chainhero.io-cert.pem
#
# List of peers to send various requests to, including endorsement, query
# and event listener registration.
#
peers:
  peer0.org1.hf.chainhero.io:
    # this URL is used to send endorsement and query requests
    url: localhost:7051
    # eventUrl is only needed when using eventhub (default is delivery service)
    eventUrl: localhost:7053

    grpcOptions:
      ssl-target-name-override: peer0.org1.hf.chainhero.io
      # These parameters should be set in coordination with the keepalive policy on the server,
      # as incompatible settings can result in closing of connection.
      # When duration of the 'keep-alive-time' is set to 0 or less the keep alive client parameters are disabled
      keep-alive-time: 0s
      keep-alive-timeout: 20s
      keep-alive-permit: false
      fail-fast: false
      # allow-insecure will be taken into consideration if address has no protocol defined, if true then grpc or else grpcs
      allow-insecure: false

    tlsCACerts:
      # Certificate location absolute path
      path: ${GOPATH}/src/github.com/chainHero/heroes-service/fixtures/crypto-config/peerOrganizations/org1.hf.chainhero.io/tlsca/tlsca.org1.hf.chainhero.io-cert.pem

  peer1.org1.hf.chainhero.io:
    # this URL is used to send endorsement and query requests
    url: localhost:8051
    # eventUrl is only needed when using eventhub (default is delivery service)
    eventUrl: localhost:8053

    grpcOptions:
      ssl-target-name-override: peer1.org1.hf.chainhero.io
      # These parameters should be set in coordination with the keepalive policy on the server,
      # as incompatible settings can result in closing of connection.
      # When duration of the 'keep-alive-time' is set to 0 or less the keep alive client parameters are disabled
      keep-alive-time: 0s
      keep-alive-timeout: 20s
      keep-alive-permit: false
      fail-fast: false
      # allow-insecure will be taken into consideration if address has no protocol defined, if true then grpc or else grpcs
      allow-insecure: false

    tlsCACerts:
      # Certificate location absolute path
      path: ${GOPATH}/src/github.com/chainHero/heroes-service/fixtures/crypto-config/peerOrganizations/org1.hf.chainhero.io/tlsca/tlsca.org1.hf.chainhero.io-cert.pem

#
# Fabric-CA is a special kind of Certificate Authority provided by Hyperledger Fabric which allows
# certificate management to be done via REST APIs. Application may choose to use a standard
# Certificate Authority instead of Fabric-CA, in which case this section would not be specified.
#
certificateAuthorities:
  ca.org1.hf.chainhero.io:
    url: http://localhost:7054
    # Fabric-CA supports dynamic user enrollment via REST APIs. A "root" user, a.k.a registrar, is
    # needed to enroll and invoke new users.
    httpOptions:
      verify: false
    registrar:
      enrollId: admin
      enrollSecret: adminpw
    # [Optional] The optional name of the CA.
    caName: ca.org1.hf.chainhero.io
    tlsCACerts:
      # Certificate location absolute path
      path: ${GOPATH}/src/github.com/chainHero/heroes-service/fixtures/crypto-config/peerOrganizations/org1.hf.chainhero.io/ca/ca.org1.hf.chainhero.io-cert.pem

entityMatchers:
  peer:
    - pattern: (\w*)peer0.org1.hf.chainhero.io(\w*)
      urlSubstitutionExp: localhost:7051
      eventUrlSubstitutionExp: localhost:7053
      sslTargetOverrideUrlSubstitutionExp: peer0.org1.hf.chainhero.io
      mappedHost: peer0.org1.hf.chainhero.io

    - pattern: (\w*)peer1.org1.hf.chainhero.io(\w*)
      urlSubstitutionExp: localhost:8051
      eventUrlSubstitutionExp: localhost:8053
      sslTargetOverrideUrlSubstitutionExp: peer1.org1.hf.chainhero.io
      mappedHost: peer1.org1.hf.chainhero.io

  orderer:
    - pattern: (\w*)orderer.hf.chainhero.io(\w*)
      urlSubstitutionExp: localhost:7050
      sslTargetOverrideUrlSubstitutionExp: orderer.hf.chainhero.io
      mappedHost: orderer.hf.chainhero.io

  certificateAuthorities:
    - pattern: (\w*)ca.org1.hf.chainhero.io(\w*)
      urlSubstitutionExp: http://localhost:7054
      mappedHost: ca.org1.hf.chainhero.io

接下来我们需要创建一个文件夹

mkdir $GOPATH/src/github.com/chainHero/heroes-service/blockchain

创建一个文件为sdk.go

vi $GOPATH/src/github.com/chainHero/heroes-service/blockchain/sdk.go

便可以编写SDK了，代码如下。

package blockchain

import (
	"github.com/hyperledger/fabric-sdk-go/pkg/client/channel"
	"github.com/hyperledger/fabric-sdk-go/pkg/core/config"
	"github.com/hyperledger/fabric-sdk-go/pkg/fabsdk"
)

var (
	SDK				*fabsdk.FabricSDK//定义一个指向fabsdk.go里面的FabricSDK的结构体
	ChannelName		= "mychannel"//当前将要访问的智能合约所属通道名称
	ChaincodeName	= "mycc"//网络编写时的链码名称
	Org				= "org1"
	User			= "Admin"
	ConfigPath		= "/home/work/go/src/trace-back/application/config.yaml"//configPath配置路径
	TargetEndPoint1 = "node2.organization1.gdzce.cn"//指定背书节点
	TargetEndPoint2 = "node2.organization2.gdzce.cn"//指定背书节点
	TargetEndPoint3 = "node2.organization3.gdzce.cn"//指定背书节点
)

// 初始化
func Init()  { 
	var err error
	SDK, err = fabsdk.New(config.FromFile(ConfigPath))
	if err != nil {
		panic(err)
	}
}

// 交互
func ChannelExecute(fcn string, args [][]byte) (channel.Response, error) {
	// 创建客户端
	ctx := SDK.ChannelContext(ChannelName, fabsdk.WithOrg(Org), fabsdk.WithUser(User))
	cli, err := channel.New(ctx)
	if err != nil {
		return channel.Response{}, err
	}
	resp, err := cli.Execute(channel.Request{
		ChaincodeID:     ChaincodeName,
		Fcn:             fcn,
		Args:            args,
	}, channel.WithTargetEndpoints(TargetEndPoint1, TargetEndPoint2, TargetEndPoint3))
	if err != nil {
		return channel.Response{}, err
	}
	return resp, nil
}

// 查询
func ChannelQuery(fcn string, args [][]byte) (channel.Response, error) {
	// 创建客户端
	ctx := SDK.ChannelContext(ChannelName, fabsdk.WithOrg(Org), fabsdk.WithUser(User))
	cli, err := channel.New(ctx)
	if err != nil {
		return channel.Response{}, err
	}
	return cli.Query(channel.Request{
		ChaincodeID:     ChaincodeName,
		Fcn:             fcn,
		Args:            args,
	}, channel.WithTargetEndpoints(TargetEndPoint1, TargetEndPoint2, TargetEndPoint3))
}

这便完成了sdk的编写了，其它的后面再说。