This project was a part of my undergraduate thesis.

A blockchain based marketplace

This project is composed of four different components. Hyperledger Fabric, Hyperledger Composer, an API server developed with loopback framework, and three client applications developed with Angular framework.

• The underlying blockchain is provided by Hyperledger Fabric.
• Hyperledgr composer is used for defining the business network, It includes the logic(smart contracts), models, and access controls for different particpants of the network.
• An API server is developed in loopback for interacting with the network. It provides a full REST API for all of the entities and transactions in the network. It also includes Authentication and a wallet service.
• three client web applications developed with Angular for different participants of the entwork. regulator-app, broker-app, member-app.

These four layers are essentially stacked on top of each other and each layer serves a different purpose and enable modularity:
Fabric (blockchain) <- Composer(smart contracts, models, and ACLs) <- API Server(REST API, Wallet service, Authentication) <- Web apps(users)

Business Network

A business network consists of participants, assets, and transactions. Each participant have an issued identity. Participants can use their identity card to interact with the network using the Composer CLI or the client apps.

Participants should trust the API server if they want to use client applications, because their identity cards should be uploaded to their wallet. Any participant can also interact with the network using Composer CLI if they don't want to trust the API server.

Installation

1. To install prerequisites follow the steps in this link. It will install Docker and Node.js. Run the following commands to verify installation. An Ubuntu machine is required.

   nvm --version
   docker --version
   

2. Then follow steps 1 to 4 of this link.
3. Then Run the following commands to create your peer admin card.

   cd ~/fabric-dev-servers
   ./startFabric.sh
   ./createPeerAdminCard.sh
   ./stopFabric.sh
   

4. clone the repository

   sudo apt-get install git
   git clone https://github.com/AiDirex/basic-marketplace
   

5. then install modules

   cd basic-marketplace
   npm install
   

6. Then start the Fabric network and package and install the marketplace application on the blockchain.

   npm run prepublish
   npm run start
   

7. After the network is started, add a sample Regulator object using the composer CLI and the admin card.

   composer participant add -c admin@coin-marketplace -d '{
     "$class": "net.aidin.marketplace.Regulator",
     "regulatorId": "reg1",
     "name": "regulator",
     "description": "regulator"
   }'
   

8. Then issue an identity for the regulator. The issued identity is stored at regulator1.card file in the current working directory.

   composer identity --issuer true issue -c admin@coin-marketplace -f regulator1.card -u reg1 -a "resource:net.aidin.marketplace.Regulator#reg1"
   

9. You can import the card in the regulator application to use it. Or directly import it to the composer wallet if you intend to only use the CLI.
10. Install MongoDB community edition by following instructions in this link. The REST server uses MongoDB to store authentication data, cards, and map these cards to authenticated users. You can configure the MongoDB connection in ./api-server/server/datasources.json
11. Copy ./api-server/server/providers-example.json to ./api-server/server/providers.json
12. For authentication in web applications we can use OAuth services provided by Google or Github. Follow steps in this link to get a client-secret and client-id from google. Put your credentials in clientID and clientSecret in provider.json file. Use localhost:4200 everywhere needed, instead of localhost:3000 that is specified in the tutorial link.
13. Then you can start the REST server

    cd api-server
    npm run install
    npm run start
    

14. Finally you can start web applications.
    • To start regulators application:

      cd ../client-apps/regulator-app
      npm run install
      npm run start
      

    • To start brokers application:

      cd ../client-apps/broker-app
      npm run install
      npm run start
      

    • To start members application:

      cd ../client-apps/member-app
      npm run install
      npm run start
      

15. Use login button to authenticate, then upload a card in the wallet section to start using the application.

Other commands

• You can import the card to the composer wallet.

  composer card import --file regulator1.card
  

  Or you can import it in the regulator's application wallet section to use it.

• To delete a card using composer CLI.

  composer card delete -c reg1@coin-marketplace
  

• To delete card of the business network admin

  composer card delete -c admin@coin-marketplace
  

• To list imported cards

  composer card list