public/subjects/blockchain/sign-service

Sign Service

The goal of this raid is to create a web service that allows users to upload, sign and store the hash of documents on the blockchain and to

Functionalities

Our signing service consist of three sections.

• Title and short presentation of the service
• Upload a document and connect a wallet
• Actions : sign, publish and verify

Presentation This section introduces the service and redirects to the two other pages

Connection

• a button to upload a document to the webpage
• a button Connect Wallet to connect an Ethereum wallet. It should handle MetaMask. Optionnaly you could use wallet connet

Action

• a button sign offline to sign the document offline
  • The resulting signature is displayed on the page or in a modal
• a button publish to store hash of the transaction on the blockchain
  • The transaction is created to add the hash to a smart contract.
  • The transaction is signed by the wallet and send
  • Optionally : The document can be stored in the database of your choice
• a button verify to check if a document has been stored previously. - It hashes the document, reads if the smart contract contains it, and displays the data at which the document was added Optionally
• A retrieve section allows to recover a document from its hash. The document must have been stored

Result

The overall appearance can be basic but it should be clear and easy to use.

Example of interface

==== Introduction ====
This is a signing service
==== Upload and connection ====
[connect wallet]
<Current document>  [upload document]
==== Actions ====
[sign]      | [publish]         | [verify]
<Signature> | <Confirmation>    | <Result>

<> are displays [] are buttons

Structure

The structure of the project is

project
│ README.md
│ package.json
│
└── server
│   │ index.js
│
└── interface
│   │ index.html
│   │ style.css
│   └── js
│       | main.js
|       | blockchain.js
└── Contracts
   │ storage.sol

Scripts and documentation

Package.json must contain following scripts:

• deploy that compile and deploy the smart contract with the tooling of your choice on a local blockchain (that must be launched too)
  • If the tooling is not available it should instruct the user how to install it
• serve that launches the server that serves the page on localhost:3000
• start that does all of the above

The project must contain a readme file that introduces the project and instructs how to use i