pegnet-community / pegnet-chainlink-client Goto Github PK

This repository contains two parts

1. Pegnet Chainlink Contracts

Contracts contains an implementation of Chainlink oracle contract which can be used by any Ethereum dApp to request data for any pegnet.

2. Chainlink Price Scraper Server

Server repository scrapes data from Chainlink feed from https://feeds.chain.link/ and returns prices for all symbols with USD pairs

Implementation of a Chainlink requesting contract to fetch peg attributes from Pegnet Explorer API.

This chainlink smart contract can be used to query and create Chainlink oracles for a given peg price, volume, supply or price change by peg symbol.

How to run

To run the scraping server

The server is an Express/NodeJS app.

cd server
sudo npm install
npm start

This will start the scraping server at port 3000. The latest chainlink feed data can then be requested by sending a GET request to http://localhost:3000 This can further be deployed on a instance to provide a static IP which all pegnet Oracle miners can query from. Sample response would look like

{"data":[{"symbol":"ETH","price":"238.245"},{"symbol":"BTC","price":"9118.641"},
{"symbol":"AUD","price":"0.663"},{"symbol":"EUR","price":"1.131497"},
{"symbol":"CHF","price":"1.068"},{"symbol":"GBP","price":"1.299"},
{"symbol":"JPY","price":"0.00950606"},{"symbol":"XAG","price":"17.308"},
{"symbol":"XAU","price":"1687.745"},{"symbol":"LINK","price":"4.664"}]}

To deploy the contracts

1. Go to the contract file /contracts/PegnetChainlinkConsumer.sol and uncomment the line 10 of the file to set the link price for each request.

For mainnet request prices check the price of your chosen of your oracle provider node here https://docs.chain.link/docs/decentralized-oracles-ethereum-mainnet#config For Testnet deployments request prices are simplified to 1 Link for 1 request.

2. Compile and deploy the contracts to your network of choice.

3. Fund the contract with Chainlink token. For Ropsten you get request chainlink token from the faucet at https://ropsten.chain.link/

Method definitions - The contract allows any smart contract to request the following attibutes of each pegged token.

1. To request current price of a pegged token call the requestPegCurrentPrice method
2. To request last updated timestamp of a pegged token call the requestPegLastUpdate method
3. To request last volume of the pegged token call the requestPegVolume method.
4. To request last reported of the pegged token call the requestPegSupply method.

Each method takes in three arguments. The oracle_address, job_id and symbol of the pegged token.

For instance to request the current price of the pETH pegged token on Ropsten network, a consumer smart contract will send a request to requestPegCurrentPrice("0xc99B3D447826532722E41bc36e644ba3479E4365", "3cff0a3524694ff8834bda9cf9c779a1", "pETH")

The complete list of chainlink oracle addresses and job ids on the testnet can be obtained here and for the mainnet can be obtained here.