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A key application of Blockchain being currently explored is a Decentralized Energy network. The idea stems from a neighborhood where certain Residents are producing energy through Solar panels or other means, and can sell excess energy to Residents needing energy. The transactions would be based on coins in each Resident's account. As per a pre-determined contract and rate, the coins would be debited from the consumer and credited to the producer, for a certain billing period. Each transaction would need to be atomic and added to a Blockchain ledger for trust and verification. The network can include Banks to transact coins for Fiat currency (USD). The network can have Utility Company who can buy or provide energy through the network.
In this code pattern, we will create such a Blockchain application using Hyperledger Composer. The network consists of Residents, Banks and Utility Companies. Residents can exchange coins for energy among each other. The application assumes a pre-paid system where transactions occur after the energy is consumed and the values are updated. The Resident can exchange coins for Fiat money (USD) with Banks on the network. The Residents can also transact coins for energy with a Utility company on the network.
This code pattern is for developers looking to start building Blockchain applications with Hyperledger Composer. When the reader has completed this code pattern, they will understand how to:
- Create business network using Hyperledge Composer and recording transactions on Blockchain ledger
- Deploying the networking to an instance of Hyperledger Fabric
- Building an Angular app to interact with the network through REST API
- The administrator interacts with Decentralized Energy UI comprising of Angular framework
- The application processes user requests to the network through a REST API.
- Implements requests to the Blockchain state database on Hyperledger Fabric v1
- The REST API is used to retrieve the state of the database
- The Angular framework gets the data through GET calls to the REST API
- Hyperledger Composer
- Angular Framework
- Loopback
Follow these steps to setup and run this code pattern. The steps are described in detail below.
- Operating Systems: Ubuntu Linux 14.04 / 16.04 LTS (both 64-bit), or Mac OS 10.12
- Docker (Version 17.03 or higher)
- npm (v5.x)
- Node (version 8.9 or higher - note version 9 is not supported)
- to install specific Node version you can use nvm
- Hyperledger Composer
- to install composer cli
npm install -g composer-cli - to install composer-rest-server
npm install -g composer-rest-server - to install generator-hyperledger-composer
npm install -g generator-hyperledger-composer
- to install composer cli
- Clone the repo
- Setup Fabric
- Generate the Business Network Archive
- Deploy to Fabric
- Run Application
- Create Participants
- Execute Transactions
Clone the Decentralized-Energy-Composer code locally. In a terminal, run:
git clone https://github.com/IBM/Decentralized-Energy-Composer
cd Decentralized-Energy-Composer
These commands will kill and remove all running containers, and should remove all previously created Hyperledger Fabric chaincode images:
docker kill $(docker ps -q)
docker rm $(docker ps -aq)
docker rmi $(docker images dev-* -q)
All the scripts will be in the directory /fabric-tools. Start fabric and create peer admin card:
cd fabric-tools/
./downloadFabric.sh
./startFabric.sh
./createPeerAdminCard.sh
Next generate the Business Network Archive (BNA) file from the root directory:
cd ../
npm install
The composer archive create command in package.json has created a file called decentralized-energy-network@0.1.15.bna.
Now, we are ready to deploy the business network to Hyperledger Fabric. This requires the Hyperledger Composer chaincode to be installed on the peer,then the business network archive (.bna) must be sent to the peer, and a new participant, identity, and associated card must be created to be the network administrator. Finally, the network administrator business network card must be imported for use, and the network can then be pinged to check it is responding.
First, install the business network:
composer network install --card PeerAdmin@hlfv1 --archiveFile decentralized-energy-network@0.1.15.bna
Start the business network:
composer network start --networkName decentralized-energy-network --networkVersion 0.1.15 --networkAdmin admin --networkAdminEnrollSecret adminpw --card PeerAdmin@hlfv1 --file networkadmin.card
Import the network administrator identity as a usable business network card:
composer card import --file networkadmin.card
Check that the business network has been deployed successfully, run the following command to ping the network:
composer network ping --card admin@decentralized-energy-network
First, go into the angular-app folder and install the dependency:
cd angular-app/
npm install
To start the application:
npm start
The application should now be running at:
http://localhost:4200
The REST server to communicate with network is available here:
http://localhost:3000/explorer/
Once the application opens, create participants and fill in dummy data. Create Residents, Banks and Utility Companies.
Execute transactions manually between Residents, Resident and Bank, and Resident and Utility Company. After executing transactions, ensure the participants account values are updated.
At the end of your session, stop fabric:
cd ~/fabric-tools
./stopFabric.sh
./teardownFabric.sh
This application demonstrates a basic idea of a decentralized energy network using Blockchain and can be expanded in several ways:
- Adding specific permissions and participant access
- Setting up real time transactions among participants
- Integrating with IoT to read from power meter and distribute energy
The blockchain network can be deployed to IBM Cloud.
You can use the IBM Blockchain platform and start for free under Starter Membership Plan. Follow these instructions to deploy the business network to IBM Blockchain platform.
To deploy the Blockchain network as kubernetes cluster follow the instructions here. The guide walks through creating a free cluster on IBM Cloud and deploying your business network. This will provide the IP address for the composer rest server to be used by the application.