Using the Oracle contract, you can use your own node to fulfill requests. This guide will show you how to deploy your own Oracle contract and add jobs to your node so that it can provide data to smart contracts.
Before you begin this guide, complete the following tasks to make sure you have all of the tools that you need:
- Set up XDCPay and obtain Apothem(Testnet) PLI.
- Configure a Xinfin client with an active WebSocket connection.
- Run a Plugin Node and connect it to a supported database.
- Fund the XDC Wallet address that your Plugin node uses. You can find the address in the node Operator GUI under the Keys tab. The address of the node is the
Regulartype. You can obtain test ETH from several faucets.
Your node works with several different types of addresses. Each address type has a specific function:
- Node address: This is the address for your Plugin node wallet. The node requires native blockchain tokens at all times to respond to requests. For this example, the node uses XDC. When you start a Plugin node, it automatically generates this address. You can find this address on the Node Operator GUI under Keys > Account addresses.
- Oracle contract address: This is the address for contracts like
Oracle.solthat are deployed to a blockchain. Do not fund these addresses with native blockchain tokens such as XDC. When you make API call requests, the funds pass through this contract to interact with your Plugin node. This will be the address that smart contract developers point to when they choose a node for an API call.
- Admin wallet address: This is the address that owns your
Oracle.solcontract addresses. If you're on OCR, this is the wallet address that receives PLI tokens.
- 1.Go to Remix and open the
Oracle.solsmart contract. The contents of this file will be very minimal.
pragma solidity 0.4.24;
- 1.On the Compile tab, click the Compile button for
Oracle.sol. Remix automatically selects the compiler version and language from the
pragmaline unless you select a specific version manually.
- 2.On the Deploy and Run tab, configure the following settings:
- Select the "Oracle" contract from the Contract menu.
- Copy the PLI token contract address for the network(like Mainnet, Apothem as given below) you are using and paste it into the
address_linkfield next to the Deploy button:
Compile the program and you should see "green tick"
Click Deploy. XDCPay prompts you to confirm the transaction.
If the transaction is successful, a new address displays in the Deployed Contracts section. Keep a note of the Oracle contract address(let's remember this address as OCA to refer to). You need it later for your contract consumption.