–signature-policy：设置背书策略
出现以下错误：
Error: proposal failed with status: 500 - failed to invoke backing implementation of 'ApproveChaincodeDefinitionForMyOrg': currently defined sequence 3 is larger than requested sequence 2
序列号不是当前合约序列号，只需要改成最新的序号即可，假如是这里，sequence值改成3即可
Error: proposal failed with status: 500 - failed to invoke backing implementation of 'ApproveChaincodeDefinitionForMyOrg': attempted to redefine uncommitted sequence (4) for namespace mycc with unchanged content
存在当前最新的合约没有commit，无法进行新的approve，只需要将最新的commit后再进行这次新的approve即可。
切换节点重复命令，知道满足lifecycle策略 
假如在操作上都approve成功了，还是出现以下情况：
我的实践是直接先commit，commit成功就可以继续走.
3.1.1 提交合约
每次调用完approve之后，必须commit才能起效。
控制台输入以下命令:
> peer lifecycle chaincode commit -o orderer.example.com:7050 --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 --channelID mychannel --name mycc --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.crt --peerAddresses peer0.org2.example.com:9051 --tlsRootCertFiles /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org2.example.com/peers/peer0.org2.example.com/tls/ca.crt --version 1 --sequence 2 --init-required --signature-policy "OR('Org1MSP.member','Org2MSP.member')"
控制台输出以下结果表示成功 
此时查询a的值为90
3.1.2 验证背书策略
前面设置的背书策略为组织1成员或者组织2成员背书即满足， 此时指定背书节点为peer0.org1.example.com.
> peer chaincode invoke -o orderer.example.com:7050 --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 -C mychannel -n mycc --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.crt -c '{"Args":["invoke","a","b","10"]}'
控制台输出如下：
重新查询a的值为80，更新成功
将背书策略修改为 “AND(‘Org1MSP.member’,‘Org2MSP.member’)”
> peer lifecycle chaincode approveformyorg --signature-policy "AND('Org1MSP.member','Org2MSP.member')" --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 --channelID mychannel --name mycc --version 1 --init-required --package-id mycc_1:4ad799ccef18d596f8c175fe1849cadc63f92a5efb1e7332712fbb2827a2ec6f --sequence 3 --waitForEvent
> peer lifecycle chaincode commit -o orderer.example.com:7050 --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 --channelID mychannel --name mycc --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.crt --peerAddresses peer0.org2.example.com:9051 --tlsRootCertFiles /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org2.example.com/peers/peer0.org2.example.com/tls/ca.crt --version 1 --sequence 3 --init-required --signature-policy "AND('Org1MSP.member','Org2MSP.member')"
同样只设置peer0.org1.example.com节点，重新invoke，查看节点日志结果如下：
ERRO 0ed VSCC error: stateBasedValidator.Validate failed, err validation of endorsement policy for chaincode mycc in tx 15:0 failed: signature set did not satisfy policy
不满足背书策略，因为我们已经重新设置为"AND(‘Org1MSP.member’,‘Org2MSP.member’)"
接下来，我们通过设置键级别背书策略的方法，将上面操作完成.
3.2 键级别背书策略设置
键级别的背书策略是通过
对于私有数据，以下功能适用： 
Go shim提供了扩展功能，允许链码开发人员根据组织的MSP标识符来处理认可策略 
根据官方给的说明 假如需要两个特定组织来批准key更改，设置key的背书策略，请将两个org都传递MSPIDs给AddOrgs()，然后调用Policy()构造可以传递给的认可策略字节数组SetStateValidationParameter() 接下来我们进行实践
3.2.1 编辑合约提供修改背书策略方法
首先导入相关依赖包 
新增function 设置背书策略
endorsement具体实现如下：
由于新增了引入包，先下载依赖 进入合约目录输入以下命令
> go mod vendor
3.2.2 升级合约
参考 Fabric2.0
> peer chaincode invoke -o orderer.example.com:7050 --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 -C mychannel -n mycc --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.crt --peerAddresses peer0.org2.example.com:9051 --tlsRootCertFiles /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org2.example.com/peers/peer0.org2.example.com/tls/ca.crt -c '{"Args":["endorsement","a","Org2MSP","add"]}'
查看peer日志，交易成功。
只设置peer0.org1节点作为背书节点。
> peer chaincode invoke -o orderer.example.com:7050 --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 -C mychannel -n mycc --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.crt -c '{"Args":["addTen","a"]}'
查看节点日志如下，提示不满足策略，因为前面设置的是AND(“Org1MSP.member”,“Org2MSP.member”) 
修改背书策略，删除Org2MSP
> peer chaincode invoke -o orderer.example.com:7050 --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 -C mychannel -n mycc --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.crt --peerAddresses peer0.org2.example.com:9051 --tlsRootCertFiles /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org2.example.com/peers/peer0.org2.example.com/tls/ca.crt -c '{"Args":["endorsement","a","Org2MSP","del"]}'
修改成功 
重新执行以下命令：
> peer chaincode invoke -o orderer.example.com:7050 --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 -C mychannel -n mycc --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.crt -c '{"Args":["addTen","a"]}'
修改a值从110变成120，执行成功 
4. 总结
经过实践，合约的approve跟commit是明显有问题的，会出现approve完成后，checkcommit还是false,但是最终还是可以commit成功的情况，这时候只要commit成功就行了。以上这一点是比较需要注意的。Fabric2.0灵活的背书策略配还是可以的，需要chaincode源码留下评论。
转载自： https://me.csdn.net/qq_28540443
