nibiaa-devices / pizza-on-the-blockchain Goto Github PK

Hyperledger Fabric is a platform for distributed ledger solutions, underpinned by a modular architecture delivering high degrees of confidentiality, resiliency, flexibility and scalability. It is designed to support pluggable implementations of different components, and accommodate the complexity and intricacies that exist across the economic ecosystem.

Hyperledger Composer is a set of collaboration tools for building blockchain business networks that make it simple and fast for business owners and developers to create smart contracts and blockchain applications to solve business problems.

• Head over to the Composer Playground: Composer Playground

• Select "Deploy a Business Network"

• Under the "Model Network Starter Template", select "browse", and choose the [email protected] file from this repository.

• Select "Deploy"

• Select "Connect Now"

You should be presented with the following screen:

• Click on the "Model File" in the left pane. From this section you can model your business network. In our example, we are tracking the shipment of Frozen Pizzas from the Factory, to the Wholesaler, to the Retailer, down to the Customer. We're assuming each Entity (i.e. Factory), will make use of RFID tags to store information on the pizza, and will scan that tag as it's received. This information, such as timestamp, the date, and state (production, freezing, packaging, distribution) is stored on the Blockchain.

We will create multiple instances of type Entity (i.e. Factory).

Here we define the transactions that will take place on the Blockchain, such as changing the state of the pizza and which entity owns the pizza.

• Select "Script File" in the left pane. From here, you will define the transaction processor functions, these are the functions that will execute when the transactions are invoked.

The ChangeStateToProduction function will change the state of the current pizza to Production.

The same applies with the other three states. The ChangeOwner function will change the owner of the pizza to a new owner.

• Select "Access Control" from the left pane. From here, you can determine which participants of the business network have access to which assets and transactions.

• On the Top Pane, select "Test".

• From here, you can test out the transactions that you defined in the model file. On the top left, select "+ Create New Participant, and enter a unique identifier for the entity.

• Select "Create New". You should see a new entity being created. In the left Pane, under Assets, select Pizza. Select "+ Create New Asset." Fill in the details for the Pizza, and select "Create New". (For the state, select from "production", "freezing", "packaging", and "distribution). For the Owner field, select the ID of the entity you just created.
  

You should see a new Pizza asset being created.

• Select "Submit Transaction" on the bottom left. For the Transaction Type, select the "ChangeStateToFreezing" transaction, and for the "pizza" field, pass in the ID you just created when creating your pizza asset.

• Select "Submit"

You should see a notification pop up saying "Submit Transaction Successful". You can double-check by selecting "All Transactions" in the left pane, under Transactions.

• In the ChangeStateToFreezing transactions, select "view record", and you can see all the transaction related information.

That's it! You're ready to deploy your business network to the Hypelerledger Fabric.

The Hyperledger Fabric environment can only be set up on Unix environments, so for windows users, you have to install a virtual machine and set up the environment as such. For the purposes of this demo, we're going to be setting up a Ubuntu OS on VirtualBox.

Download Ubuntu: Install Ubuntu
Download VirtualBox Install VirtualBox
Instructions for setting up Ubuntu on VirtualBox Set Up Ubuntu on VirtualBox

To run Hyperledger Composer and Hyperledger Fabric, we recommend you have at least 4Gb of memory.

The following are prerequisites for installing the required development tools:

Operating Systems: Ubuntu Linux 14.04 / 16.04 LTS (both 64-bit), or Mac OS 10.12
 Docker Engine: Version 17.03 or higher
 Docker-Compose: Version 1.8 or higher
 Node: 8.9 or higher (note version 9 is not supported)
 npm: v5.x
 git: 2.9.x or higher
 Python: 2.7.x
 A code editor of your choice, we recommend VSCode.

If installing Hyperledger Composer using Linux, be aware of the following advice:

Login as a normal user, rather than root.
Do not su to root.
When installing prerequisites, use curl, then unzip using sudo.
Run prereqs-ubuntu.sh as a normal user. It may prompt for root password as some of it's actions are required to be run as root.
Do not use npm with sudo or su to root to use it.
Avoid installing node globally as root.**

If you're running on Ubuntu, you can download the prerequisites using the following commands:

curl -O https://hyperledger.github.io/composer/prereqs-ubuntu.sh chmod u+x prereqs-ubuntu.sh

Next run the script - as this briefly uses sudo during its execution, you will be prompted for your password.

./prereqs-ubuntu.sh

Follow these instructions to install the pre-requsities for installing Hyperledger Composer on a local Mac OS X machine. You need to install these tools before you attempt to install Hyperledger Composer.

First install nvm (the Node version manager). nvm is a tool that allows you to easily install, update and switch between versions of Node.js.

Open the terminal (command line) by clicking on the magnifier in the menu bar at the top right of your screen. Type terminal and press enter.

In the terminal window paste the text below and press enter:

curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.0/install.sh | bash

When you hit enter you should see the pop-up below, prompting you to install git. Press the Get Xcode button to install the full Apple Xcode IDE, including a C++ compiler, used to install native Node.js modules.

The download and install process for Xcode may take 20 minutes or more. Be patient!

After the installation of Xcode has completed launch Xcode. Accept the license agreement. It will prompt you for your username and password and will install additional components.

After Xcode finishes installing additional components and launches, simply quit Xcode.

Switch back to the terminal and create your bash profile (stores user preferences for bash):

touch .bash_profile

Then rerun the original curl command:

curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.0/install.sh | bash

Close the terminal and reopen it.

Check that nvm is installed and is accessible:

nvm —-version

Install the latest (long term support) version of Node:

nvm install --lts

Switch to the LTS version of Node:

nvm use --lts

Check that Node is installed:

node --version

Follow the instructions here to install Docker for Max (stable): Install Docker

After running the installed Docker application you should have the whale icon in your menu bar, with a green “Docker is running” status.

Install VSCode by visiting: Install VSCode

Press the “Download for Mac” button and copy the downloaded application into your Applications folder.

Type composer into the search bar and then press the Install button next to the Hyperleger Composer extension. Once the install completes you need to press the Reload button to activate the extension.

Follow these instructions to obtain the Hyperledger Composer development tools (primarily used to create Business Networks) and stand up a Hyperledger Fabric (primarily used to run/deploy your Business Networks locally). Note that the Business Networks you create can also be deployed to Hyperledger Fabric runtimes in other environments e.g. on a cloud platform.

There are a few useful CLI tools for Composer developers. The most important one is composer-cli, which contains all the essential operations, so we'll install that first. Next, we'll also pick up generator-hyperledger-composer, composer-rest-server and Yeoman plus the generator-hyperledger-composer. Those last 3 are not core parts of the development environment, but they'll be useful if you're following the tutorials or developing applications that interact with your Business Network, so we'll get them installed now.

1. Essential CLI tools:

npm install -g composer-cli

2. Utility for running a REST Server on your machine to expose your business networks as RESTful APIs:

npm install -g composer-rest-server

3. Useful utility for generating application assets:

npm install -g generator-hyperledger-composer

4. Yeoman is a tool for generating applications, which utilises generator-hyperledger-composer:

npm install -g yo

If you've already tried Composer online, you'll have seen the browser app "Playground". You can run this locally on your development machine too, giving you a UI for viewing and demonstrating your business networks.

Browser app for simple editing and testing Business Networks:

npm install -g composer-playground

This step gives you a local Hyperledger Fabric runtime to deploy your business networks to.

1. In a directory of your choice (we will assume ~/fabric-tools), get the .zip file that contains the tools to install Hyperledger Fabric:

mkdir ~/fabric-tools && cd ~/fabric-tools

curl -O https://raw.githubusercontent.com/hyperledger/composer-tools/master/packages/fabric-dev-servers/fabric-dev-servers.zip

unzip fabric-dev-servers.zip

A tar.gz is also available if you prefer: just replace the .zip file with fabric-dev-servers.tar.gz1 and the unzip command with a tar xvzf command in the above snippet.

2. Use the scripts you just downloaded and extracted to download a local Hyperledger Fabric runtime:

cd ~/fabric-tools ./downloadFabric.sh

Start the fabric:

./startFabric.sh

Generate a PeerAdmin card:

./createPeerAdminCard.sh

You can start and stop your runtime using ~/fabric-tools/stopFabric.sh, and start it again with ~/fabric-tools/startFabric.sh.

At the end of your development session, you run ~/fabric-tools/stopFabric.sh and then ~/fabric-tools/teardownFabric.sh. Note that if you've run the teardown script, the next time you start the runtime, you'll need to create a new PeerAdmin card just like you did on first time startup.

Once you have the environment set up, it's time to package everything into a .bna file. In order to do this, we're going to use a Yeoman generator to create a skeleton business network, then replace the model, script, and access control files with the ones we created earlier on in the tutorial.

1. Create a skeleton business network using Yeoman. This command will require a business network name, description, author name, author email address, license selection and namespace.

yo hyperledger-composer:businessnetwork

2. Enter pizza-on-the-blockchain for the network name, and desired information for description, author name, and author email.

3. Select Apache-2.0 as the license.

4. Select org.acme.biznet as the namespace.

5. cd into the folder which was just created and replace the contents of /pizza-on-the-blockchain/lib/org.example.biznet.cto with the model file generated earlier on in the tutorial.

6. Replace the contents of /pizza-on-the-blockchain/lib/logic.js with the script file generated earlier on in the tutorial.

7. Create a new file in the pizza-on-the-blockchain folder, called permissions.acl and paste the contents of the Access Control file generated earlier on in the tutorial.

Now that you have your busines network, it's time to package it up into a .bna file. In the pizza-on-the-blockchain directory, enter the following command:

composer archive create -t dir -n .

After the command has run, a business network archive file called [email protected] has been created in the tutorial-network directory.

After creating the .bna file, the business network can be deployed to the instance of Hyperledger Fabric. Normally, information from the Fabric administrator is required to create a PeerAdmin identity, with privileges to deploy chaincode to the peer. However, as part of the development environment installation, a PeerAdmin identity has been created already.

After the runtime has been installed, a business network can be deployed to the peer. For best practice, a new identity should be created to administrate the business network after deployment. This identity is referred to as a network admin.

A PeerAdmin business network card with the correct credentials is already created as part of development environment installation.

Deploying a business network to the Hyperledger Fabric requires the Hyperledger Composer chaincode to be installed on the peer, then the business network archive (.bna) must be sent to the peer, and a new participant, identity, and associated card must be created to be the network administrator. Finally, the network administrator business network card must be imported for use, and the network can then be pinged to check it is responding.

1. To install the composer runtime, run the following command:

composer runtime install --card PeerAdmin@hlfv1 --businessNetworkName pizza-on-the-blockchain

The composer runtime install command requires a PeerAdmin business network card (in this case one has been created and imported in advance), and the name of the business network.

2. To deploy the business network, from the pizza-on-the-blockchain directory, run the following command:

composer network start --card PeerAdmin@hlfv1 --networkAdmin admin --networkAdminEnrollSecret adminpw --archiveFile [email protected] --file networkadmin.card

The composer network start command requires a business network card, as well as the name of the admin identity for the business network, the file path of the .bna and the name of the file to be created ready to import as a business network card.

3. To import the network administrator identity as a usable business network card, run the following command:

composer card import --file networkadmin.card

The composer card import command requires the filename specified in composer network start to create a card.

4. To check that the business network has been deployed successfully, run the following command to ping the network:

composer network ping --card admin@pizza-on-the-blockchain

The composer network ping command requires a business network card to identify the network to ping.

Hyperledger Composer can generate a bespoke REST API based on a business network. For developing a web application, the REST API provides a useful layer of language-neutral abstraction.

1. To create the REST API, navigate to the pizza-on-the-blockchain directory and run the following command:

composer-rest-server

2. Enter admin@pizza-on-the-blockchain as the card name.

3. Select never use namespaces when asked whether to use namespaces in the generated API.

4. Select No when asked whether to secure the generated API.

5. Select Yes when asked whether to enable event publication.

6. Select No when asked whether to enable TLS security.

The generated API is connected to the deployed blockchain and business network.

Once the REST server is up and running, head over to https://localhost:3000/explorer

It should look a little like this:

This is a Python Flask web application built as an interface for the Blockchain network running on Hyperledger Fabric. The application utilises REST APIs (generated using the Composer REST Server) to connect to the Blockchain network and perform GET, POST and PUT requests.

This application was built with the Flask Microframework. The UI of the application was built with MaterializeCSS, a front-end framework based on Material Design.

1. Ensure Python is installed on your local environment (Both Python 2 and Python 3 are supported).
2. Install the requirements using the command pip install -r requirements.txt.
3. Run the application as: python application.py.
4. Point your web browser to the address localhost:<port>.

Please feel free to contact me with any questions/comments.

Once you start up the application, you should be able to see this page:

Browse to the Factory page, and select Production as the Pizza state. Press Submit.

You can see the Current Status has changed to production. Now, when filling the form, select Freezing. Press Submit.

Now, try Packaging.

Finally, select Distribution.

Now, select Transfer Ownership, to transfer the ownership of the pizza to the Wholesaler. This will automatically take you to the Wholesaler page, and you can see the transaction issued onto the Blockchain.

Select Transfer Ownership again.

Select Transfer Ownership one more time.

From here, the Customer can keep track of their pizza through the entire process.

And that's it! See how simple it is? If you're interested in learning more about Blockchain, check out some useful links:

https://www.ibm.com/blockchain/what-is-blockchain.html

https://hyperledger.github.io/composer/