akc-example-dapp

Example showing the dapp of fabric network.

Akachain sdk

In this example we are using akachain sdk named: akc-node-sdk-external-cc version ^v1.0.1. To be install the sdk you need to create the .npmrc file, please read and follow the guide.

Config

We need to configure the necessary network variables to execute the chaincode, create .env file based on content in env_example file:

• TARGET_NAME: List of endorsing peer, when passing an empty array ([]), it will automatically send to all peers according to the network's settings.
• FABRIC_CLIENT_ROOT_PATH: cert location.

# Chaincode
TARGET_NAME=["peer0-operator.operator","peer0-merchant.merchant"]
ORG_NAME=OPERATOR
CHAINCODE_USER=operator
CHANNEL_NAME=exampleChannel
CHAINCODE_ID=chaincode_cc
FABRIC_CLIENT_ROOT_PATH=/data/app

Services

The services that call to the network are defined in the file ./services/chaincode.js which have simple functions, which call into the akachain sdk library. We interact with these two functions through the export function processRequestChainCode(funcName, args, invoke), and the boolean variable invoke acts as the route.

async function processRequestChainCode(funcName, args, invoke) {
  const params = [];
  params.push(JSON.stringify(args));

  const orgname = process.env.ORG_NAME;
  const username = process.env.CHAINCODE_USER;
  const channelName = process.env.CHANNEL_NAME;
  const chaincodeId = process.env.CHAINCODE_ID;
  const artifactFolder = process.env.FABRIC_CLIENT_ROOT_PATH;
  const req = {
    orgname,
    chaincodeId,
    channelName,
    username,
    args: params,
    funcName,
    artifactFolder,
  };
  let resultCc;
  if (invoke) {
    resultCc = await invokeChaincode(req);
  } else {
    resultCc = await queryChaincode(req);
  }

  return resultCc;
}

Dapp

Assuming we have a chaincode running on the network that has a chaincode function invoke named "function_invoke" and a chaincode function query named "function_query" with input corresponding to each function:

const FUNCTION_INVOKE = "function_invoke"
const FUNCTION_QUERY = "function_query"
const sdk = require("./services/chaincode");

//call function invoke onchain
async function callInvokeOnchain(data) {
    const result = await sdk.processRequestChainCode(
        FUNCTION_INVOKE,
        data,
        true
    );

    return true;
}

//call function query onchain
async function callQueryOnchain(data) {
    const result = await sdk.processRequestChainCode(
        FUNCTION_QUERY,
        data,
        false
    );

    return true;
}

callInvokeOnchain({ dataInvoke: [], example: "xxx" });
callQueryOnchain({ dataQuery: [], example: "xxx" });

Run Dapp

Run dapp with command:

npm start