📘 Hyperledger Fabric Assignment This repository contains the internship assignment implementation using Hyperledger Fabric:

Level-1 → Setup and run the Fabric test network Level-2 → Develop and deploy a Java chaincode (AccountContract) Level-3 → Build a Spring Boot REST API that invokes the chaincode and containerize it with Docker 🚀 Prerequisites Ensure you have the following installed:

Docker & Docker Compose Git Java 17+ Maven 3.8+ Hyperledger Fabric Samples & Binaries Clone Fabric samples:

git clone https://github.com/hyperledger/fabric-samples.git cd fabric-samples

Optional: checkout stable branch

git checkout release-2.5

Download Fabric binaries & images:

curl -sSL https://bit.ly/2ysbOFE | bash -s -- 2.5.0 1.5.0 🧩 Level-1: Start Test Network From inside fabric-samples/test-network:

Start Fabric test network with 2 orgs, orderer, CA, CouchDB

./network.sh up createChannel -c mychannel -s couchdb

To stop and clean

./network.sh down This creates mychannel where we will deploy the Java chaincode.

⚙️ Level-2: Java Chaincode 📂 Code location: chaincode-java/

The chaincode (AccountContract) manages account assets with fields:

DEALERID, MSISDN, MPIN, BALANCE, STATUS, TRANSAMOUNT, TRANSTYPE, REMARKS Key Functions CreateAccount(id, dealerId, msisdn, mpin, balance, status) ReadAccount(id) UpdateAccount(id, mpin, status, remarks) ApplyTransaction(id, amount, trType, remarks) (trType = credit | debit) GetAccountHistory(id) GetAllAccounts() Build Chaincode cd chaincode-java mvn clean package Deploy Chaincode From fabric-samples/test-network:

./network.sh deployCC -ccn accountcc -ccp ../chaincode-java -ccl java Quick Test (CLI) docker exec -it cli bash

Create account

peer chaincode invoke -C mychannel -n accountcc
-c '{"function":"CreateAccount","Args":["acct1","dealer123","+919900112233","1234","1000.0","ACTIVE"]}'

Query account

peer chaincode query -C mychannel -n accountcc
-c '{"Args":["ReadAccount","acct1"]}' 🌐 Level-3: REST API (Spring Boot) 📂 Code location: rest-api-java/

The REST API uses Fabric Gateway Java SDK to connect to Fabric and invoke the chaincode.

Endpoints Method Endpoint Description POST /accounts Create new account GET /accounts/{id} Read account PUT /accounts/{id} Update account fields POST /accounts/{id}/transaction Apply credit/debit GET /accounts/{id}/history Get account history Configuration Update rest-api-java/src/main/resources/application.properties:

server.port=8080 fabric.connection.profile=connection.json fabric.wallet.path=wallet fabric.user=appUser fabric.channel=mychannel fabric.chaincode=accountcc ⚠️ Copy connection.json from fabric-samples/test-network/organizations/peerOrganizations/org1.example.com/ ⚠️ Copy user credentials into rest-api-java/wallet/ (e.g. appUser created by test-network). Do not commit private keys to GitHub.

Run Locally cd rest-api-java mvn spring-boot:run Build JAR mvn clean package java -jar target/fabric-rest-api-java-1.0.0.jar Run with Docker cd rest-api-java docker build -t fabric-rest-api-java:1.0 .

docker run -d --name fabric-rest-api -p 8080:8080
-v $(pwd)/connection.json:/app/connection.json
-v $(pwd)/wallet:/app/wallet
--network test-network_default
fabric-rest-api-java:1.0 🧪 Example API Usage Create Account curl -X POST http://localhost:8080/accounts
-H "Content-Type: application/json"
-d '{"id":"acct1","dealerID":"dealer123","msisdn":"+919900112233","mpin":"1234","balance":1000,"status":"ACTIVE"}' Read Account curl http://localhost:8080/accounts/acct1 Debit Transaction curl -X POST http://localhost:8080/accounts/acct1/transaction
-H "Content-Type: application/json"
-d '{"amount":100,"trType":"debit","remarks":"purchase"}' Account History curl http://localhost:8080/accounts/acct1/history 📂 Repository Layout hyperledger-fabric-assignment/ ├── README.md ├── chaincode-java/ # Java chaincode (AccountContract) ├── rest-api-java/ # Spring Boot REST API + Dockerfile ├── docs/ # Supporting docs (assignment.pdf, screenshots) └── instructions/ # Helper scripts and guides ⚠️ Notes & Best Practices Use Java 17+ for both chaincode and REST API. Use Fabric v2.4+ with test-network. Never commit wallet credentials or private keys to public repos. For money, prefer integer minor units (e.g., cents) instead of floating-point. REST API connects with Fabric Gateway and needs proper network config. ✅ Next Steps Clone this repo Start Fabric test-network (Level-1) Build & deploy chaincode (Level-2) Run REST API locally or in Docker (Level-3) Test endpoints with curl/Postman 🔗 This completes the Hyperledger Fab