jefftellew / certificatechain

Repo for our project CertificateChain

CertificateChain: Decentralized Healthcare Training Certificate Management System using Blockchain and Smart Contracts

Repo for our project CertificateChain. This project aims to create a blockchain-based database system to store certificates, as well as creating a java-based web app for users to interact with the system through.

Authors

Jeff Tellew¹ and Tsung-Ting Kuo² †

1 University of California Santa Barbara, Santa Barbara, CA, USA

2 UCSD Health Department of Biomedical Informatics, University of California San Diego, La Jolla, CA, USA

† Corresponding Author

Introduction

This repo contains all code for our project, CertificateChain. Source code as well as testing scripts used to automate our experiments are both contained within this repo. There is also code for the web app that we tested with other DBMI members at the same time. Lastly, there are some example certificate PDF files that were used during experiments.

Contact

Thank you for using our software. If you have any questions or suggestions, please kindly contact Jeff Tellew (jefftellew at gmail dot com), University of California Santa Barbara, Santa Barbara, CA, USA.

Installation

This section will go over installing all of the necessary components to run the web app.

These steps include commands that are specifically for a BASH shell and directory structures that match Unix directories. If you are on Windows, you will need to adjust accordingly.

Installing geth

First, you will need to install geth. This can be done with the following steps.

1. Download geth 1.8.11, available from here. You should download the binary file, not the installer. If you are on Ubuntu, this is a direct download link.
2. Unpack the archive by running the command tar xvzf geth-linux-amd64-1.8.11-dea1ce05.tar.gz
3. Install geth by running the command cp geth-linux-amd64-1.8.11-dea1ce05/geth /usr/bin/geth and cp geth-linux-amd64-1.8.11-dea1ce05/geth /usr/local/bin
4. Run the command geth version to ensure that geth is properly installed.

Installing ethereum

Next, you will need to install some things for Ethereum. This is just a sequence of commands.

1. apt-get install software-properties-common
2. add-apt-repository -y ppa:ethereum/ethereum
3. add-apt-repository -y ppa:openjdk-r/ppa
4. apt-get update
5. apt-get install solc openjdk-8-jdk

Clone the repo

Finally, you will need to clone this repo. If you haven't already, and aren't sure how, see GitHub's help page. You may need to install git using apt-get install git and maven using apt-get install maven

Once you're done with that, you're all ready to go!

Launching the Web App on a Server

The process of launching the web app on a server like an AWS Virtual Machine should be fairly straightforward. This section will explain the steps to take in order to do so.

1. Follow the steps in the Installation section to set everything up.
2. Change into the root directory of the repo, which should be called dbmi-19
3. Start geth by running the script startGeth.sh. If you are running this on a Unix machine, you can use screen to run geth in the background. This is accomplished by creating a screen, starting geth with the script, and then detaching from the screen. The commands to do this are screen -S geth followed by ./scripts/startGeth.sh. Then, hit the keys CTRL + a + d OR enter the command screen -d to detach. If you are not able to use screen or simply don't want to, you will need to find another way to run the script in the background or you will not be able to keep the web app running.
4. Start the web app. Again, if you have access to it, you can use screen to run this in the background. This can be accomplished with the command screen -S web-app followed by the command mvn spring-boot:run. Once more, use the key sequence CTRL + a + d OR use the command screen -d to detach from the screen. You will need to be in the repo root directory where pom.xml is located, which should be dbmi-19 unless something has been changed.

Launching the Web App Locally

You can launch the web app locally either from the command line as a .jar or from within an IDE like IntelliJ. This section will briefly cover how to launch the web app using IntelliJ.

1. Follow the steps in the Installation section to set everything up.
2. Open IntelliJ and create a new project from an existing source. From the menu bar at the top, this would be File > New > Project from Existing Sources....
3. Navigate to the location you downloaded the repo to and enter the repo root directory.
4. Find the file named pom.xml and select it.
5. Click "OK" to finish creating the project.
6. Start geth by running startGeth.sh. You can either run it through the file explorer or through the terminal.
7. Run the web app by clicking the green arrow near the top right of the screen. If you can't find it, you can also run it from the menu bar at the top by navigating to Run > Run 'CertificatesApplication' or by using the keyboard shortcut (Shift + F10 on Windows, not sure on Mac or Linux)

Switching between Windows and Unix-based OS

There are a few small changes that need to be made to change between a machine running Windows and one running a Unix-based OS like Linux or a Mac.

In particular, there are modifications that need to be made to two files:

• startGeth.sh
• CertificateDBSC.java

startGeth.sh

1. Open startGeth.sh in your text editor of choice (found in /dbmi-19/scripts/)
2. Locate the lines near the top of the file that are marked with *** UNIX *** and *** WINDOWS ***
3. Make sure that the lines in the section for the OS you are using are uncommented, and that the lines in the section for the other OS are commented out.

CertificateDBSC.java

1. Open CertificateDBSC.java in your text editor of choice (found in /dbmi/src/main/java/edu/ucsd/dbmi/certificates/contract/)
2. Locate the line near the top of the file in the INSTANCE VARIABLES section that defines the variable private static String dir
3. Make sure that the line marked with the OS you are using is uncommented, and that the line marked with the OS you are not using is commented out