ccorley / fabric-client

A node.js Hyperledger Fabric client

fabric-client

fabric-client is a Node.js Hyperledger Fabric blockchain client that allows transactions to be sent to the blockchain via a REST API or a NATS listener. The fabric-client works with the fhir-data smart contract to provide storage of FHIR patient resources in the blockchain.

Pre-requisites

The fabric-client requires Node.js and a Hyperledger Fabric to connect to.

• Install Node.js

If you don't have a Hyperledger Fabric instance and would like to install the Hyperledger Fabric test-network on your local machine, you can follow the "testing with test-network" instructions below.

Clone fabric-client

git clone https://github.com/ccorley/fabric-client.git

The fabric-client repo contains fhir-data.tar.gz which is a Hyperledger Fabric Typescript contract for storing FHIR-R4 Patient records in the blockchain. Install this contract in your Hyperledger Fabric network, or follow the instructions below to install it in a test-network instance.

Test with test-network

The fabric client can be tested using a local Hyperledger Fabric test-network instance. Follow the steps below to set up test-network on your local machine.

Install Hyperledger fabric-samples

Follow the instructions to install the Hyperledger Fabric samples repository and pre-requisites.

Start the test-network

cd fabric-samples/test-network
./network.sh up createChannel -c channel1 -ca

Copy the contract to the test-network

Copy the contract to the test-network directory. It will be installed in later step.

cp <fabric-client-path>/fabric-client/fhir-data.tar.gz .

Install the contract

Install the contract (chaincode) as Org1.

export CORE_PEER_TLS_ENABLED=true
export CORE_PEER_LOCALMSPID="Org1MSP"
export CORE_PEER_TLS_ROOTCERT_FILE=${PWD}/organizations/peerOrganizations/org1.example.com/peers/peer0.org1.example.com/tls/ca.crt
export CORE_PEER_MSPCONFIGPATH=${PWD}/organizations/peerOrganizations/org1.example.com/users/[e-mail]/msp
export CORE_PEER_ADDRESS=localhost:7051
peer lifecycle chaincode install fhir-data.tar.gz

You should see a result like:

2021-06-01 15:49:26.260 CDT [cli.lifecycle.chaincode] submitInstallProposal -> INFO 001 Installed remotely: response:<status:200 payload:"\nNfhir-data_1.0:b2f0f237531073839bafbe0bf1fa324c163f1b3364ad4762b8dd878ba59184c4\022\rfhir-data_1.0" > 
2021-06-01 15:49:26.262 CDT [cli.lifecycle.chaincode] submitInstallProposal -> INFO 002 Chaincode code package identifier: fhir-data_1.0:b2f0f237531073839bafbe0bf1fa324c163f1b3364ad4762b8dd878ba59184c4

Install the contract as Org2.

export CORE_PEER_LOCALMSPID="Org2MSP"
export CORE_PEER_TLS_ROOTCERT_FILE=${PWD}/organizations/peerOrganizations/org2.example.com/peers/peer0.org2.example.com/tls/ca.crt
export CORE_PEER_MSPCONFIGPATH=${PWD}/organizations/peerOrganizations/org2.example.com/users/[e-mail]/msp
export CORE_PEER_ADDRESS=localhost:9051
peer lifecycle chaincode install fhir-data.tar.gz

You should see a result like:

2021-06-01 15:52:15.817 CDT [cli.lifecycle.chaincode] submitInstallProposal -> INFO 001 Installed remotely: response:<status:200 payload:"\nNfhir-data_1.0:b2f0f237531073839bafbe0bf1fa324c163f1b3364ad4762b8dd878ba59184c4\022\rfhir-data_1.0" > 
2021-06-01 15:52:15.819 CDT [cli.lifecycle.chaincode] submitInstallProposal -> INFO 002 Chaincode code package identifier: fhir-data_1.0:b2f0f237531073839bafbe0bf1fa324c163f1b3364ad4762b8dd878ba59184c4

Approve the chaincode as Org2

Still as Org2, get the chaincode ID:

peer lifecycle chaincode queryinstalled

You should see a result like:

Installed chaincodes on peer:
Package ID: fhir-data_1.0:b2f0f237531073839bafbe0bf1fa324c163f1b3364ad4762b8dd878ba59184c4, Label: fhir-data_1.0

Approve the chaincode for Org2

export CC_PACKAGE_ID=fhir-data_1.0:b2f0f237531073839bafbe0bf1fa324c163f1b3364ad4762b8dd878ba59184c4
peer lifecycle chaincode approveformyorg -o localhost:7050 --ordererTLSHostnameOverride orderer.example.com --channelID channel1 --name fhir-data --version 1.0 --package-id $CC_PACKAGE_ID --sequence 1 --tls --cafile "${PWD}/organizations/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem"

You should see a result like:

2021-06-01 15:58:05.614 CDT [chaincodeCmd] ClientWait -> INFO 001 txid [eb957a579478747bc19e47254e024eaae4d14f4c23888782a826c26950b789e1] committed with status (VALID) at localhost:9051

Approve the chaincode as Org1

export CORE_PEER_LOCALMSPID="Org1MSP"
export CORE_PEER_MSPCONFIGPATH=${PWD}/organizations/peerOrganizations/org1.example.com/users/[e-mail]/msp
export CORE_PEER_TLS_ROOTCERT_FILE=${PWD}/organizations/peerOrganizations/org1.example.com/peers/peer0.org1.example.com/tls/ca.crt
export CORE_PEER_ADDRESS=localhost:7051
peer lifecycle chaincode approveformyorg -o localhost:7050 --ordererTLSHostnameOverride orderer.example.com --channelID channel1 --name fhir-data --version 1.0 --package-id $CC_PACKAGE_ID --sequence 1 --tls --cafile "${PWD}/organizations/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem"

You should see a result like:

2021-06-01 16:01:16.349 CDT [chaincodeCmd] ClientWait -> INFO 001 txid [a54c5bffb61364921927df0d05863b2e390e6a4b100c093c4c29c383b86dcaa8] committed with status (VALID) at localhost:7051

Commit the chaincode definition to the channel

Check the approvals:

peer lifecycle chaincode checkcommitreadiness --channelID channel1 --name fhir-data --version 1.0 --sequence 1 --tls --cafile "${PWD}/organizations/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem" --output json

You should see a result like:

{
    "approvals": {
        "Org1MSP": true,
        "Org2MSP": true
    }
}

Commit the chaincode:

peer lifecycle chaincode commit -o localhost:7050 --ordererTLSHostnameOverride orderer.example.com --channelID channel1 --name fhir-data --version 1.0 --sequence 1 --tls --cafile "${PWD}/organizations/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem" --peerAddresses localhost:7051 --tlsRootCertFiles "${PWD}/organizations/peerOrganizations/org1.example.com/peers/peer0.org1.example.com/tls/ca.crt" --peerAddresses localhost:9051 --tlsRootCertFiles "${PWD}/organizations/peerOrganizations/org2.example.com/peers/peer0.org2.example.com/tls/ca.crt"

You should see a result like:

2021-06-01 16:05:15.427 CDT [chaincodeCmd] ClientWait -> INFO 001 txid [771b01791594bd09a8462e33252c6a2c125ede6126aa03971ed05ce09b1ffae0] committed with status (VALID) at localhost:7051
2021-06-01 16:05:15.430 CDT [chaincodeCmd] ClientWait -> INFO 002 txid [771b01791594bd09a8462e33252c6a2c125ede6126aa03971ed05ce09b1ffae0] committed with status (VALID) at localhost:9051

Check the commit:

peer lifecycle chaincode querycommitted --channelID channel1 --name fhir-data --cafile "${PWD}/organizations/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem"

You should see a result like:

Committed chaincode definition for chaincode 'fhir-data' on channel 'mychannel':
Version: 1.0, Sequence: 1, Endorsement Plugin: escc, Validation Plugin: vscc, Approvals: [Org1MSP: true, Org2MSP: true]

Configure the client

Copy your connection json to your fabric-client/conf directory. Example for test-network:

cd test-network
cp organizations/peerOrganizations/org1.example.com/connection-org1.json <fabric-client-path>/fabric-client/conf

You can also edit the fabric-client config.json in fabric-client/conf and adjust the settings for your fabric, but you should be able to use the configuration with test-network without changes. Please see the table below if you do need to make changes:

Setting	Example	Description
channel	channel1	The channel on which your Hyperledger Fabric contract is deployed.
contract	fhir-data	The name of the deployed contract.
port	9043	The port on which the fabric client listens for incoming REST API calls.
connection_profile	conf/connection-org1.json	The location of the Hyperledger Fabric connection profile.
wallet_location	conf/wallet	The location of the Hyperledger Fabric wallet directory.
use_discovery	true	Whether to use the fabric-network API's discovery service. Use true if your Hyperledger Fabric servers are DNS discoverable, otherwise use false.
as_local_host	true	If your Hyperledger Fabric servers are running locally and use_discovery is true, use true, otherwise use false.
use_nats	false	Whether to use NATS to receive messages from LinuxForHealth. This should always be true when using LinuxForHealth.
nats_servers	["localhost:4222"]	An array of NATS servers from which the fabric client will receive messages.
nats_nkey	conf/certs/nats-server.nk	The NATS nkey private key that the client needs to connect to the LinuxForHealth NATS server.
nats_ca_file	./conf/certs/lfh-root-ca.pem	The CA file to use when connecting to the LinuxForHealth NATS server.
enroll_admin	true	When using test-network, whether to enroll the admin. In general this will be true, at least initially when using test-network. Once the id is in the local wallet, you can leave it set to true or change it to false.
admin_name	admin	The name of the admin to enroll when enroll_admin is true.
admin_pw	adminpw	The password of the admin to enroll when enroll_admin is true.
register_user	true	When using test-network, whether to enroll a user. In general this will be true, at least initially when using test-network. Once the id is in the local wallet, you can leave it set to true or change it to false.
user_name	admin	The name of the user to register when register_user is true.
certificate_authority	ca.org1.example.com	The name of the Hyperledger Fabric CA to specify when register_user is true.
msp_id	Org1MSP	The name of the Hyperledger Fabric Membership Service Provider to use when register_user is true.

Start the client

cd fabric-client
node.js server.js

That's it - you're ready to send FHIR Patient transactions to the REST API and store them in your blockchain!