Polygon DID Registry Contract

This library is an implementation of a registry contract that supports the Polygon DID Method.

Overview

The Polygon registry contract acts as a public ledger, where the Polygon-Identity specified Decentralised Identifiers will be logged. The specifications related to polygon DID method are mentioned in the document. A DID generated using the Polygon DID generator, can be stored and managed on the ledger using this contract library.

Contract Deployment

Network	ChainId	Registry Address
Polygon Mainnet	137	0x98bF771e1E93Db917A89986bcdaBa3b43643F367
Polygon Testnet	80001	0x8B335A167DA81CCef19C53eE629cf2F6291F2255

Methods

• createDID(address, string) : The method createDID is used to create and log a new DID on the polygon chain. The parameter of address type, will act as the reference key, to refer the did document stored on the chain. The string type variable will contain the did document, that will be stored on the matic chain.

• updateDIDDoc(address, string) : The method updateDID is included in contract, which will facilitate the controller, and only the controller of the did, to update the document if need arises. Though the Polygon DID method, defines how the DID doc is defined as per standards, and that can be resolved.

• deleteDIDDoc(address) : The method deleteDID is included in the contract, that only the controller of DID can access, to delete a particular DID from ledger.

• getDIDDoc(address) : The method getDID helps to resolve the DID document.

• transferOwnership(address) : The method transferOwnership, helps in transferring the ownership of contract to a new owner. Only the current owner can access this function.

• getOwner() : the method getOwner helps one to fetch the current owner of the contract.

• getTotalNumberOfDIDs() : the method getTotalNumberOfDIDs helps one to fetch the total number of DIDs ever written on Polygon Ledger, with the number of currently active DIDs.

• getTotalNumberOfDeletedDIDs(): the method getTotalNumberOfDeletedDIDs helps one fetch the total number of DIDs deleted from Polygon Ledger.

• getDIDDOcByIndex(uint256) : The method getDIDDOcByIndex helps,to resolve DID document by index.

Example ethers code

Using ethers, the following illustrates how one can interact with PolygonRegistry contract, from client side application.

Loading the Contract

const ethers = require('ethers');
const url = https://rpc-mumbai.matic.today; // For matic testnet
const DID_ADDRESS = `<Contract Address>`;
const provider = new ethers.providers.JsonRpcProvider(url);

let wallet = new ethers.Wallet(`<Signer Key/Private Key>`, provider);
let registry = new ethers.Contract(DID_ADDRESS, <Contract ABI>, wallet);

Creating a DID

let returnHashValues = await registry.functions.createDID(<DID address>, DidDoc);

Updating a DID

let returnHashValues = await registry.functions.updateDIDDoc(<DID address>, DidDoc)

Delete a DID

let returnHashValues = await registry.functions.deleteDIDDoc(<DID address>)

Resolving a DID

let returnDidDoc = await registry.functions.getDIDDoc(<DID address>);

Deploying the Contract on Matic network

Pre-requisites

• NodeJS

https://nodejs.org/en/download/

• Truffle

https://www.trufflesuite.com/docs/truffle/getting-started/truffle-with-metamask

• Ganache

https://www.trufflesuite.com/ganache

• A wallet connected to polygon network, with Matic token in it. One can receive the Matic Test Tokens from their faucet.

Deployment

Clone the above repository

git clone https://gitlab.com/polygon-did/polygon-did-smart-contract.git

Install Dependencies

npm i

Run a ganache instance (only required for Local Deployment)

ganache-cli

Update your and RPC URL in .env file.

RPCURL="<Place your RPC URL here>"
SIGNER="<Place your mnemonic/Private Key here>"

On a new console window run

truffle migrate --network <network name>

Testing

For Testing use the command

truffle test

The test cases run on a ganache setup.