What is a BlockChain? Blockchain is a distributed database that maintains a continuously-growing list of ordered records called blocks. This technology underlying and other cryptocurrencies. It is a public ledger of all Bitcoin transaction. These blocks are added in a chronological order. In order to deploy a Blockchain application, you need a distributed Hyperledger Blockchain on your choice of infrastructure (on-premise or cloud). Bitcoin In this article, we will deploy a Hyperledger Fabric cluster using Docker. Prerequisites To follow this guide you need a system with working Docker engine and docker-compose on it. We will use Fabric which is an implementation of Blockchain technology written in Golang, so go version go1.6.2 or above is required. Before proceeding further let’s have a look on Hyperledger Fabric. The HyperLedger Project Hyperledger is an open source project with collaborative effort created to advance Blockchain technology. It helps in cross-industry distributed ledgers which support transaction system, property transaction, and other services. HyperLedger Fabric is an implementation of blockchain technology. It provides a modular architecture allowing pluggable implementations of the various function. Fabric Setting HyperLedger Cluster Pulling Images First, pull the latest images published by the Hyperledger fabric project from DockerHub. docker pull hyperledger/fabric-peer:latest docker pull hyperledger/fabric-membersrvc:latest Now in order to run these images. Create a docker-compose file which will launch both of these services. membersrvc: image: hyperledger/fabric-membersrvc ports: - "7054:7054" command: membersrvc vp0: image: hyperledger/fabric-peer ports: - "7050:7050" - "7051:7051" - "7053:7053" environment: - CORE_PEER_ADDRESSAUTODETECT=true - CORE_VM_ENDPOINT=unix:///var/run/docker.sock - CORE_LOGGING_LEVEL=DEBUG - CORE_PEER_ID=vp0 - CORE_PEER_PKI_ECA_PADDR=membersrvc:7054 - CORE_PEER_PKI_TCA_PADDR=membersrvc:7054 - CORE_PEER_PKI_TLSCA_PADDR=membersrvc:7054 - CORE_SECURITY_ENABLED=false - CORE_SECURITY_ENROLLID=test_vp0 - CORE_SECURITY_ENROLLSECRET=MwYpmSRjupbT links: - membersrvc command: sh -c "sleep 5; peer node start --peer-chaincodedev" That’s it now we are ready to launch these service by simply running docker-compose up Running the ChainCode Before running chain code you need to set your $GOPATH and then make a directory to download the sample chain code in the src directory. mkdir -p $GOPATH/src/github.com/chaincode_example02/ cd $GOPATH/src/github.com/chaincode_example02 Curl --request GET https://raw.githubusercontent.com/hyperledger/fabric/master/examples/chaincode/go/chaincode_example02/chaincode_example02.go > chaincode_example02.go Next, you’ll need to download the Hyperledger fabric to your local $GOPATH, after that you have to build the chain code. mkdir -p $GOPATH/src/github.com/hyperledger cd $GOPATH/src/github.com/hyperledger git clone http://gerrit.hyperledger.org/r/fabric Go to directory and build the code chaincode_example02 cd $GOPATH/src/github.com/chaincode_example02 go build Starting And Registering The ChainCode Run the following command to start the chain code. CORE_CHAINCODE_ID_NAME=mycc CORE_PEER_ADDRESS=0.0.0.0:7051 ./chaincode_example02 After that chain code console will display the message “Received REGISTERED, ready for invocations” which shows that chain code is ready for use. Running Rest API To log in with the help of REST API, send a POST request to the /registrar endpoint, with the enrolment ID and enrolment PW. These parameters are listed in the eca.users section of the membersrvc.yaml file. REST Request POST localhost:7050/registrar { "enrollId": "jim", "enrollSecret": "6avZQLwcUe9b" } REST Response: 200 OK { "OK": "Login successful for user 'jim'." } Continue Reading the Full Article at: XenonStack.com/blog
