Block chain Development
shilparock
BLCN532_Lab03_Middleware1.docxBLCN532 Lab 3
Middleware
Introduction
This lab introduces you to the layer of functional code that exists between smart contract chaincode and the user-focused application. Middleware acts as both a service and interface layer. In this lab you’ll examine source code and configuration files that make up the middleware layer and then invoke functionality through an exposed service.
Lab Deliverables:
To complete this lab, you must create a Lab Report file and submit the file in iLearn. The Lab Report file must be a Microsoft Word format (.docx), and have the filename with the following format:
BLCN532_SECTION_STUDENTID_LASTNAME_FIRSTNAME_Lab03.docx
· SECTION is the section number of your current course (2 digits)
· STUDENTID is your student ID number (with leading zeros)
· LASTNAME is your last name
· FIRSTNAME is your first name
To get started, create a Microsoft Word document (.docx) with the correct filename for this lab. You’ll be asked to enter text and paste screenshots into the lab report file.
NOTE: All screenshots MUST be readable. A screenshot that I cannot read (i.e. cannot read the text you are capturing) will not count for any points.
SECTION 1: Installing tools and dependencies
Step 1.1: Building an application: Installing tools and dependencies
First, you’ll log into your development environment and install a few tools and dependencies.
1. Before you start this lab, make sure that you view the lab video and increase the memory of your VM. You need that extra memory to successfully complete this lab.
2. Open PowerShell
3. PS %HOME%> cd vagrant\hyperledger
4. PS %HOME%\vagrant\Hyperledger> vagrant up
5. Launch PuTTY -> open connection (Vagrant Hyperledger)
6. $ cd $GOPATH/src/trade-finance-logistics/middleware
7. Good news!!! The virtual machine we’re using already has node.js and npm installed!!
8. $ node -v
9. $ npm -v
10. Create a screenshot of the results of steps 5-8, and paste that screenshot into your Lab Report File.
11. Install fabric-ca-client and fabric-client
a. Two methods:
i. $ npm install fabric-ca-client
ii. $ npm install fabric-client
b. OR, just $ npm install
12. Create a screenshot of the results of npm install, and paste that screenshot into your Lab Report File.
Step 1.2: Configuring the network and application
Next, you’ll examine the network configuration.
1. Open the config.json file ($ nano config.json)
2. Scroll down to the entry that defines the Carrier organization. (carrierorg)
3. Create a screenshot that shows the url, requests, and events attributes of the carrierorg definition, and paste that screenshot into your Lab Report File.
4. Exit from the nano editor.
5. Open the clientUtils.js file ($ nano clientUtils.js)
6. Scroll down to the function named registerAndEnrollUser.
7. Briefly read through the code and comments to see how the JavaScript program carries out the tasks of registering and enrolling a new user.
8. Create a screenshot that shows the first several lines of the registerAndEnrollUser function, and paste that screenshot into your Lab Report File.
9. Exit from the nano editor.
10. Open the createTradeApp.js file ($ nano createTradeApp.js)
11. Scroll down to the line in which “Wood for Toys” requests a new trade action.
12. Create a screenshot that shows the JavaScript code from step 11, and paste that screenshot into your Lab Report File.
13. Exit from the nano editor.
Step 1.3: Install and run, and invoke the chaincode
1. $ cd $GOPATH/src/trade-finance-logistics/network
2. Remove previous cryptographic material
a. $ rm -rf client-certs
3. $ ./trade.sh up
4. Open a New PuTTY connection (Vagrant Hyperledger)
NOTE: This is the SECOND PuTTY CONNECTION for screenshots in later steps.
5. $ cd $GOPATH/src/trade-finance-logistics/middleware
6. $ node createTradeApp.js
7. Create a screenshot that shows results from step 5, and paste that screenshot into your Lab Report File.
8. (In the FIRST PuTTY CONNECTION window) $ docker ps -a
a. Scroll to display the dev-peers
9. Create a screenshot that shows results from step 7, and paste that screenshot into your Lab Report File.
10. $ node runTradeScenarioApp.js
11. Create a screenshot that shows results from step 9, and paste that screenshot into your Lab Report File.
Step 1.4: Run the blockchain client application
1. $ cd $GOPATH/src/trade-finance-logistics/application
2. $ npm install
3. $ node app.js
4. Create a screenshot that shows results from step 3, and paste that screenshot into your Lab Report File.
5. Open a New PuTTY connection (Vagrant Hyperledger)
NOTE: This is the THIRD PuTTY CONNECTION for screenshots in later steps.
6. $ cd $GOPATH/src/trade-finance-logistics/application
7. $ curl -s -X POST http://localhost:4000/login -H "content-type: application/x-www-form-urlencoded" -d 'username=Jim&orgName=importerorg'
8. $ curl -s -X POST http://localhost:4000/login -H "content-type: application/x-www-form-urlencoded" -d 'username=admin&orgName=importerorg&password=adminpw'
9. Copy the value of the token you got back from the results of step 8 to your clipboard.
a. In Linux, just highlighting text at the command line copies that text to your clipboard.
10. $ curl -s -X POST http://localhost:4000/channel/create -H "authorization: Bearer PASTE THE TOKEN VALUE FROM STEP 8 HERE"
11. Create a screenshot that shows results from step 10, and paste that screenshot into your Lab Report File.
Section 2: Wrapping up
Now that you have installed, run, and tested your chaincode, you need to properly shutdown your business network.
1. In the FIRST PuTTY CONNECTION $ ./trade.sh down
2. Exit from your Linux sessions
3. $ exit
4. In Windows PowerShell, shut down your Hyperledger virtual machine:
5. PS %HOME%\vagrant\Hyperledger> vagrant halt
6. Create a snapshot of your Ubuntu VM in VirtualBox. This allows you to easily restore to this point if you ever need to “undo” subsequent steps and return to a known point.
You should have 10 screenshots in your Lab Report File. Save your file and submit it in iLearn as a file attachment for the Lab 3 assignment.
Congratulations! You have complete lab 3.
