This project is the outcome of a mini-hackathon in which the BigchainDB and TheLedger teams participated on the 16-17 of August 2018.

The high level design specification is available at - ./specs/design.md

The directory structure of this project is as below :

.
├── LICENSE
├── README.md
├── bdb-hyperledger-oracle/
│  
├── data_job/
│   
├── hyperledger-chainservice/
│  
├── specs/
│   
└── ui/

This is a node based cron job that posts transactions to BigchainDB network.

This is a react based app to access REST API of Hyperledger Fabric chain service. This UI is for demo usage of the BigchainDB-Hyperledger Fabric oracle. The web form first creates a BigchainDB asset by taking passphrase and asset data (a number). Once the asset is created, the asset id is passed to a Hyperledger chain-code which internally passes it to the oracle. The oracle then queries BigchainDB with the asset id and executes a callback passed by the Hyperledger chain-code. The oracle then sends back the results to Hyperledger chain service.

This is hyperledger chain-service that interacts with the fabric network.

This project is an express API that functions as an oracle between Hyperledger Fabric (here in hyperledger-chainservice/) and BigchainDB.

In a real scenario, the chain-code can do pre-processing and create a dynamic callback before sending the request to the oracle.

• BigchainDB network is up and running
• Hyperledger network is up and running (to run the Hyperledger fabric network, run the startFabric.sh script in the /hyperledger-network/scripts directory)

• Create .env files in the root of each of oracle, chainservice and ui based on their .env.example files, respectively.

• Update the .env values as per your network and node IP addresses and ports.

• From new terminal, in hyperledger-chainservice/ execute yarn and yarn run start:watch. This will start Hyperledger-chaincode REST server to be consumed by UI.

• From new terminal, in ui/, execute npm install and then npm start. This will start react application on port 3000.

• From another new terminal, run docker-compose build and docker-compose up from the root directory. This will bring up the oracle.

• In your browser, visit http://localhost:3000, you will see UI for this project.
• Follow the instructions on the web page.