sample-standalone-app.md

Node.js Standalone Application in Vagrant

This section describes how to run a sample standalone Node.js application which interacts with a Hyperledger Fabric block chain.

1. If you haven't already done so, see Setting Up The Application Development Environment to get your environment set up. The remaining steps assume that you are running inside the vagrant environment.

2. Issue the following commands to build the Node.js Client SDK:

   cd /opt/gopath/src/github.com/hyperledger/fabric
   make node-sdk
   

3. Start the membership services and peer processes. We run the peer in dev mode for simplicity.

   cd /opt/gopath/src/github.com/hyperledger/fabric/build/bin
   membersrvc > membersrvc.log 2>&1&
   peer node start --peer-chaincodedev > peer.log 2>&1&
   

4. Build and run chaincode example 2:

   cd /opt/gopath/src/github.com/hyperledger/fabric/examples/chaincode/go/chaincode_example02
   go build
   CORE_CHAINCODE_ID_NAME=mycc CORE_PEER_ADDRESS=0.0.0.0:30303 ./chaincode_example02 > log 2>&1&
   

5. Put the following sample app in a file named app.js in the /tmp directory. Take a moment (now or later) to read the comments and code to begin to learn the Node.js Client SDK APIs.

   /*
    * A simple application utilizing the Node.js Client SDK to:
    * 1) Enroll a user
    * 2) User deploys chaincode
    * 3) User queries chaincode
    */
   // "HFC" stands for "Hyperledger Fabric Client"
   // we are using the path to the HFC because we have not globally installed the package
   var hfc = require('/opt/gopath/src/github.com/hyperledger/fabric/sdk/node');
   
   var chain, user, chaincodeID;
   
   // Create a chain object used to interact with the chain.
   // You can name it anything you want as it is only used by client.
   chain = hfc.newChain("mychain");
   // Initialize the place to store sensitive private key information
   chain.setKeyValStore( hfc.newFileKeyValStore('/tmp/keyValStore') );
   // Set the URL to membership services and to the peer
   chain.setMemberServicesUrl("grpc://localhost:7054");
   chain.addPeer("grpc://localhost:7051");
   // The following is required when the peer is started in dev mode
   // (i.e. with the '--peer-chaincodedev' option)
   chain.setDevMode(true);
   
   // Begin by enrolling the user
   enroll();
   
   // Enroll a user.
   function enroll() {
      console.log("enrolling user admin ...");
      // Enroll "admin" which is preregistered in the membersrvc.yaml
      chain.enroll("admin", "Xurw3yU9zI0l", function(err, admin) {
         if (err) {
            console.log("ERROR: failed to register admin: %s",err);
            process.exit(1);
         }
         user = admin;
         deploy();
      });
   }
   
   // Deploy chaincode
   function deploy() {
      console.log("deploying chaincode; please wait ...");
      // Construct the deploy request
      var req = {
          chaincodeName: 'mycc',
          fcn: "init",
          args: ["a", "100", "b", "200"]
      };
      // Issue the deploy request and listen for events
      var tx = user.deploy(req);
      tx.on('complete', function(results) {
          // Deploy request completed successfully
          console.log("deploy complete; results: %j",results);
          // Set the testChaincodeID for subsequent tests
          chaincodeID = results.chaincodeID;
          query();
      });
      tx.on('error', function(err) {
          console.log("Failed to deploy chaincode: request=%j, error=%k",req,err);
          process.exit(1);
      });
   
   }
   
   // Query chaincode
   function query() {
      console.log("querying chaincode ...");
      // Construct a query request
      var req = {
         chaincodeID: chaincodeID,
         fcn: "query",
         args: ["a"]
      };
      // Issue the query request and listen for events
      var tx = user.query(req);
      tx.on('complete', function (results) {
         console.log("query completed successfully; results=%j",results);
         process.exit(0);
      });
      tx.on('error', function (err) {
         console.log("Failed to query chaincode: request=%j, error=%k",req,err);
         process.exit(1);
      });
   }

6. Run the application as follows:

   cd /tmp
   node app
   

7. Congratulations! You've successfully run your first Hyperledger Fabric application.

Next, see Hyperledger Fabric Client (HFC) SDK for Node.js to learn more about writing your own applications.