cuongquangnam / ContactTracing

ContactTracing

This is a demo aiming to showcase the use of Decentralized ID and Blockchain to solve the problem of verification and contact tracing of COVID-19 pandemic.

The project uses Truffle + Ganache testnet for testing.

Further development may include creation of QR code representing the URL for the json certificate so that the verifier can check by scanning the code.

The demo video and use case description can be found here: https://devpost.com/software/streamlining-contact-tracing-to-reopen-our-economy

Veritrace

Installation Guide:

Install Ganache from https://www.trufflesuite.com/ganache

Install Nodejs from https://nodejs.org/en/download/

Install Truffle with npm npm install -g truffle

Install all dependencies with npm npm install

Guide:

1. Clone the repo git clone https://github.com/cuongquangnam/ContactTracing.git
2. Create a new workspace in ganache for this project and in the configuration under truffle projects select add project and select the file location of your truffle-config folder. The file location should look something like C:\Users\sydel\Desktop\did\ContactTracing\truffle-config.js
3. Open the repo you have cloned in your text editor.
4. Open the terminal in the same working directory.
5. In the terminal, truffle compile Notice corresponding json files to the smart contracts appear in build/contracts. truffle migrate Notice that balance of eth in ganache's first account decreases after contracts are migrated. Clicking on the contract tab of ganache shows which contracts have been deployed and the addresses of the contracts. truffle console brings up the truffle console which will be used to run some functions in the smart contract. While in truffle console,
   • var myContractBF = await BuildingFactory.deployed() This fetches the buildingFactory object deployed in ganache.
   • myContractBF.set_didfactory("get-did-document-factory-address-from-ganache-tab-contracts") Calls set_didfactory function from buildingFactory object.
   • myContractBF.createBuilding("Building1","100","244") myContractBF.createBuilding("Building2","340","1144") myContractBF.createBuilding("Building3","1040","2444") Creates some building objects which will be used for the demo.
   • myContractBF.getBuildingAt(0) myContractBF.getBuildingAt(1) myContractBF.getBuildingAt(2) Returns did of the building created. Should be in the format 'did:ether:f7317f93f6163e0611a6ebface56e36e2ff6ce9c'
   • var buildingOne = await Building.at('get-building-address-from-building-1-did') This fetches the building 1 object that was created earlier. An example is var buildingOne = await Building.at('0xf7317f93f6163e0611a6ebface56e36e2ff6ce9c')
   • buildingOne.set_companyOwner("get-random-address-account-to-be-owners-address") For the companyOwner's address select a random address from the ganache accounts tab. An example would be buildingOne.set_companyOwner("did:ether:0x9416a4Fc66b90d72C3697cb06edeAd7774A74a3a") where 0x9416a4Fc66b90d72C3697cb06edeAd7774A74a3a is the random address selected to be the owner's address.
6. Next we edit the code with the new addresses and private keys we have obtained.
   • change the DIDDocumentFactory.abi and buildingFactory.abi address in server.js which can be obtained from the contracts tab in ganache. For example, both take the format of 0x982993cCa0B474070c652e8363bD7e16A962613E
   • change the privateKey and accountAddr fields in server.js to the private key corresponding to the companyOwner's address and the company owner's address. The private key of the account can be found in ganache's account tab by clicking on the key icon on the rightmostside of the account address. An example is var privateKey = "7f155baaba59074655bceb20c21f6d1ce835b00a7c0b0ff3797c6f56d52bfa8c"; var accountAddr = "0x9416a4Fc66b90d72C3697cb06edeAd7774A74a3a";
   • change all the buildingAddress in files/scriptVerify.js with the addresses obtained earlier. For example buildingAddress = 0xf7317f93f6163e0611a6ebface56e36e2ff6ce9c
   • change all the displayed address in 'verify.html' with the addresses obtained earlier. For example did:ether:0xf7317f93f6163e0611a6ebface56e36e2ff6ce9c
7. Add a new terminal and do node server
8. Access localhost:3000/sign.html on your preferred browser (should be best if on Chrome)
9. Select a random account address from the ganache accounts tab to be a worker's address and replace it with workerDID in the following format. Replace companyOwnerDID with the previously selected companyOwner account from ganache. {"workerDID":"did:ether:0x767fa9Fca86f8326e273f98506ad3B57893F6B4c","companyOwnerDID":"did:ether:0x9416a4Fc66b90d72C3697cb06edeAd7774A74a3a"} Use the private key of the companyOwner. The private key of the account can be found in ganache's account tab by clicking on the key icon on the rightmostside of the account address. Private key has 64 characters, example: E9873D79C6D87DC0FB6A5778633389F4453213303DA61F20BD67FC233AA33262 Press submit query. The response will be in the following format. {"workerDID":"did:ether:0x767fa9Fca86f8326e273f98506ad3B57893F6B4c","companyOwnerDID":"did:ether:0x9416a4Fc66b90d72C3697cb06edeAd7774A74a3a","signature":"0xa81da85a0f5e6fadb4bac943485e3281f01d90c12a2b3266cd8ba2e44836973e237f1b50d35515d50e3b31435ec4ad61b95aa17bd7310994c52c6e55fc8946931c"}
10. Copy and paste the response into the verify tab of the browser and select the building that the user would like to enter.

Supported Features

1. User is able to enter the buildings that the companyOwner owns when he presents (1) a valid response for the building selected along with (2) the building number in verify.html.
2. User is denied entry for invalid response in verify.html.
3. User is not able to enter buildings twice. ie. the building must leave the building before being able to enter the same building or another building.
4. Do contact tracing by using the worker's did, for example did:ether:0x767fa9Fca86f8326e273f98506ad3B57893F6B4c or building's did, for example did:ether:0xf7317f93f6163e0611a6ebface56e36e2ff6ce9c along with an input timeframe to retrieve buildings associated with the worker's did and workers associated with the building's did in a specific timeframe respectively.

FAQ

1. Unable to see selection of date in firefox. A: Please use chrome.