Excelian hyperledger walkthrough-feb17

1

Hyperledger Fabric

Architecture

Fabric has several framework

components:

Membership services for security:

audit, registration & identity

management

Blockchain services: Consensus,

Storage & transactions

Chaincode services: Secure

container & registry

For the hackathon we will focus on

the container and blockchain

storage

2

Chaincode

REST ENDPOINTS

Hyperledger-java API

Application code

Validating P

eer

Node

Docker

conta

iner

RocksDB storage

Other Validating

PeersREST

Consensus

Consensus

Consensus

Prerequisites

Docker (I tested on 1.12.1 on Mac OS X)

Docker Compose (kitematic is also helpful)

Java/Golang environment for chaincode development (I used JDK 8 + Gradle 3.2)

For application development:

Java/Golang environment

Your favourite development language, as long as you have a REST API available

This guide loosely based on:

http://hyperledger-fabric.readthedocs.io/en/latest/starter/fabric-starter-kit/

3

The Environment

4

Starter container

Member SVCs

Peer node

Container for the member security services (not strictly required for the hackathon)

Runs and builds the Fabric Shim for interaction with Fabric

Runs and builds the java chaincode

Requires Java + gradle to be installed in the container

Deploys the Java chaincode running on peer node into Fabric

Used for executing commands against the running chaincode

Docker-compose.ymlmembersrvc:

# try 'docker ps' to see the container status after starting this compose

container_name: membersrvc

image: hyperledger/fabric-membersrvc

command: membersrvc

environment:

- COMPOSE_HTTP_TIMEOUT=120

volumes:

- /Users/jbowkett/Documents/Excelian/blockchain/dev-team/git-clone/smart-cheques/starter-

kit/docker-containers/mapped-fs-member:/user/docker-containers/mapped-fs-member

peer:

container_name: peer

image: hyperledger/fabric-peer

environment:

- CORE_PEER_ADDRESSAUTODETECT=true

- CORE_VM_ENDPOINT=unix:///var/run/docker.sock

- CORE_LOGGING_LEVEL=DEBUG

- CORE_PEER_ID=vp0

- CORE_SECURITY_ENABLED=false

# - CORE_SECURITY_PRIVACY=false

- CORE_PEER_PKI_ECA_PADDR=membersrvc:7054

- CORE_PEER_PKI_TCA_PADDR=membersrvc:7054

- CORE_PEER_PKI_TLSCA_PADDR=membersrvc:7054

- CORE_PEER_VALIDATOR_CONSENSUS_PLUGIN=noops


# this gives access to the docker host daemon to deploy chain code in network mode

volumes:

- /var/run/docker.sock:/var/run/docker.sock


kit/docker-containers/mapped-fs-peer:/user/docker-containers/mapped-fs-peer

5

# have the peer wait 10 sec for membersrvc to start

# the following is to run the peer in Developer mode - also set sample DEPLOY_MODE=dev

command: sh -c "sleep 10; peer node start --peer-chaincodedev"

#command: sh -c "sleep 10; peer node start"

links:

- membersrvc

ports:

- "5005:5005"

starter:

container_name: starter

image: hyperledger/fabric-starter-kit

volumes:

# tweak this to map a local development directory tree into the container


kit/docker-containers/mapped-fs-starter:/user/docker-containers/mapped-fs-starter

environment:

- MEMBERSRVC_ADDRESS=membersrvc:7054

- PEER_ADDRESS=peer:7051

- KEY_VALUE_STORE=/tmp/hl_sdk_node_key_value_store

# set to following to 'dev' if peer running in Developer mode


- DEPLOY_MODE=dev

- CORE_CHAINCODE_ID_NAME=mycc

- CORE_PEER_ADDRESS=peer:7051

# the following command will start the chain code when this container starts and ready it for

deployment by the app

# command: sh -c "sleep 20;

/opt/gopath/src/github.com/hyperledger/fabric/examples/chaincode/go/chaincode_example02/chai

ncode_example02"

stdin_open: true

tty: true

links:

- membersrvc

- peer

Bootstrap the Docker environments

Edit the volumes sections of your docker-compose.yml to map appropriate

directories for getting code onto your nodes

Make sure those paths exist on your development (and “production” machine)

Go to the directory the docker-compose.yml is installed:

$ docker-compose up -d

6

7

Update the peer node to run Java services

$ docker exec -it peer /bin/bash

peer$ peer node start --peer-chaincodedev

peer$ apt-get update && add-apt-repository ppa:webupd8team/java && add-

apt-repository ppa:cwchien/gradle && apt-get update && apt-get install

oracle-java8-installer

peer$ java –fullversion # should be JDK 1.8

peer$ apt-get install gradle

peer$ gradle –v # should be 3.2+

8

9

Install the chaincode shim into the gradle repo

peer$ cd $GOPATH/src/github.com/hyperledger/fabric/core/chaincode/shim/java

peer$ gradle clean build

10

The story so far….

We’ve created the 3 Hyperledger docker containers (starter, membersvc and peer)

with mounted directories on our development machine

Provisioned the peer node by installing the correct version of Java and Gradle

Built the Hyperledger shim on the peer node and installed it as an available

dependency for later Gradle builds on the peer node

Now let’s deploy an example chaincode application….

11

Install your chaincode on the peer node and run the service

import org.hyperledger.java.shim.ChaincodeBase;

import org.hyperledger.java.shim.ChaincodeStub;

public class HelloWorldChaincode extends ChaincodeBase {

public HelloWorldChaincode() { }

public String run(ChaincodeStub chaincodeStub, String function, String[] args) {

return "hello world!";

}

public String query(ChaincodeStub chaincodeStub, String function, String[] args) {

return "hello world query";

}

public String getChaincodeID() {

return "HelloWorldChaincode";

}

public static void main(String[] args) {

new HelloWorldChaincode().start(args);

}

}12

$ cp <hello world chaincode src> <mapped dir for peer>

Start the chaincode

peer$ gradle clean build runHello

$ docker exec -it starter /bin/bash

starter$ peer chaincode deploy -l java -n HelloWorldChaincode -c

'{"Args":[]}'

starter$ peer chaincode invoke -l java -n HelloWorldChaincode -c

'{"Args":[]}’

starter$ peer chaincode query -l java -n HelloWorldChaincode -c

'{"Args":[]}'

13

SUCCESS !!!!

A quick recap….

1. Create the 3 Hyperledger Docker containers (starter, membersvc and peer) with

mapped directories to our development machine

2. Provision the peer node by logging into the Docker container and installing the

correct version of Java and Gradle

3. Build the Hyperledger shim on the peer node and install it as an available

dependency for later Gradle builds on the peer node

4. Create a HelloWorld chaincode on our development machine & copy the code+build

script to the peer node using our Docker mapped-directory

5. On the starter node, deploy the chaincode into Fabric, and then use the starter node

to query the running chaincode within fabric

14

Some APIs and Examples to be aware of

Table creation:

final List<TableProto.ColumnDefinition> columnDefs = new ArrayList<>();

columnDefs.add(newBuilder().setName("hash").setKey(true).setType(STRING).build());

columnDefs.add(newBuilder().setName("messages").setKey(false).setType(STRING).build());

final boolean success = chaincodeStub.createTable(TABLE_NAME, columnDefs);

Lookup is based on the key column only

https://github.com/hyperledger/fabric/tree/master/examples/chaincode/java

Examples:

LinkExample – Invoking one chaincode from another

MapExample – Simple map storage

RangeExample – Query storage with range

SimpleExample – Transferring value using Arguments

TableExample – C/R/D Using underlying storage tables

15


Useful links

https://docs.docker.com/engine/installation/

https://docs.docker.com/engine/installation/linux/linux-postinstall/ Important on

Linux if running Docker on boot

http://hyperledger-fabric.readthedocs.io


https://github.com/jbowkett/zug-hackathon


https://gradle.org/documentation/

16



http://hyperledger-fabric.readthedocs.io/


https://github.com/jbowkett/zug-hackathon


https://gradle.org/documentation/

Technology

Excelian hyperledger walkthrough-feb17