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Using Node.js as an Application Developer with Hyperledger Fabric

This guide covers prerequisites, setup instructions, and steps for developing a Node.js application integrated with Hyperledger Fabric.

Prerequisites

For macOS:

1. Homebrew: Install Homebrew if it is not already installed.

2. Docker Desktop: Install Docker Desktop.

3. Node.js, jq, and npm: Install these packages via Homebrew:

   brew install node jq

For Linux:

1. Docker: Install Docker using your preferred package manager (e.g., apt-get, yum).
2. Node.js, jq, and npm: Install with your package manager (e.g., apt-get, yum).

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Step 1: Install Fabric Samples, Binaries, and Docker Images

Note: If you have already installed these, you can skip this step. Otherwise, run:

curl -sSL https://bit.ly/2ysbOFE | bash -s

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Step 2: Set Up Your Environment

macOS:

1. Add Fabric binaries and configuration to your PATH by appending the following lines to your .zshrc or equivalent:

   echo 'export PATH=$PWD/bin:$PATH' >> ~/.zshrc
   echo 'export FABRIC_CFG_PATH=$PWD/config' >> ~/.zshrc
   
   echo 'export CORE_PEER_TLS_ENABLED=true' >> ~/.zshrc
   echo 'export CORE_PEER_LOCALMSPID=Org1MSP' >> ~/.zshrc
   echo 'export CORE_PEER_TLS_ROOTCERT_FILE=${PWD}/test-network/organizations/peerOrganizations/org1.example.com/tlsca/tlsca.org1.example.com-cert.pem' >> ~/.zshrc
   echo 'export CORE_PEER_MSPCONFIGPATH=${PWD}/test-network/organizations/peerOrganizations/org1.example.com/users/[email protected]/msp' >> ~/.zshrc
   echo 'export CORE_PEER_ADDRESS=localhost:7051' >> ~/.zshrc

2. Apply changes by sourcing the profile:

   source ~/.zshrc

Linux:

1. Add Fabric binaries to your PATH by appending the following lines to your ~/.bashrc or equivalent:

   echo 'export PATH=$PWD/bin:$PATH' >> ~/.bashrc
   echo 'export FABRIC_CFG_PATH=$PWD/config' >> ~/.bashrc
   
   echo 'export CORE_PEER_TLS_ENABLED=true' >> ~/.bashrc
   echo 'export CORE_PEER_LOCALMSPID=Org1MSP' >> ~/.bashrc
   echo 'export CORE_PEER_TLS_ROOTCERT_FILE=${PWD}/test-network/organizations/peerOrganizations/org1.example.com/tlsca/tlsca.org1.example.com-cert.pem' >> ~/.bashrc
   echo 'export CORE_PEER_MSPCONFIGPATH=${PWD}/test-network/organizations/peerOrganizations/org1.example.com/users/[email protected]/msp' >> ~/.bashrc
   echo 'export CORE_PEER_ADDRESS=localhost:7051' >> ~/.bashrc

2. Apply changes by sourcing the profile:

   source ~/.bashrc

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Step 3: Launch the Test Network

To convert files in test-network to Unix format (if needed):

find test-network -type f -not -path "*.git*" -exec dos2unix {} +

1. Navigate to the test network directory:

   cd test-network

2. Stop any existing network (if running):

   ./network.sh down

3. Start the test network:

   ./network.sh up -ca

4. Create a channel:

   ./network.sh createChannel -c mychannel

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Step 4: Install and Instantiate Chaincode

1. Deploy the chaincode using Node.js:

   ./network.sh deployCC -ccn basic -ccp ../chaincode-javascript/ -ccl javascript

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Step 5: Set Up the Node.js Application

1. Navigate to the application directory:

   cd backend/src

2. Install the required Node.js packages:

   npm install

3. Run the application:

   node app.js

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Step 6: Enroll Users

1. Enroll Admin User:

   node caActions.js admin <orgName>

2. Register and Enroll Application User:

   node caActions.js user <orgName> <username>

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Step 7: Verify the Setup

1. Check Docker containers to ensure the Hyperledger Fabric components are running:

   docker ps

2. Interact with the application to confirm that it communicates with the Hyperledger Fabric network as expected.

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Additional Resources

• Hyperledger Fabric Documentation
• Hyperledger Fabric Samples GitHub

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This README provides a complete guide to setting up and using Node.js as an application developer with Hyperledger Fabric on macOS and Linux systems.