sj-quickstart

Welcome to the sj-quickstart repository! In this guide, we’ll walk you through creating a SafeJunction agent that functions as an Ethereum Gas Price Oracle. The goal of this agent is to retrieve the baseFeePerGas value from the latest Ethereum mainnet block and provide it to a Solidity contract deployed on the Sepolia testnet.

This is accomplished by leveraging the SafeJunction platform, which enables seamless data retrieval across different environments by utilizing one agent's output as another's input.

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Getting Started

1. Set Up Environment Variables

   First, create an .env file in the root of the project with the following content. This will store the necessary keys for deployment and interaction with the Ethereum network:

   PRIVATE_KEY=
   ETHERSCAN_API_KEY=
   SEPOLIA_JSON_RPC_URL=

   • PRIVATE_KEY: Your wallet's private key.
   • ETHERSCAN_API_KEY: Your Etherscan API key (for contract verification and gas estimation).
   • SEPOLIA_JSON_RPC_URL: The JSON-RPC URL for the Sepolia testnet.

2. Compile the Contracts

   Once the environment variables are set, compile the Solidity contracts using Hardhat:

   npx hardhat compile

3. Deploy the BaseFeePerGasOracle Contract

   After compilation, you can deploy the BaseFeePerGasOracle contract to the Sepolia network using the following command:

   npx hardhat BaseFeePerGasOracle:deploy \
   --gateway <gateway-address> \
   --network sepolia

   • Replace <gateway-address> with the actual address of the gateway you'll be using.

4. Execute and Read the Result

   To execute the agent and retrieve the baseFeePerGas from the Ethereum mainnet, run the following command:

   npx hardhat BaseFeePerGasOracle:execAndReadBaseFeePerGas \
   --gateway <gateway-address> \
   --oracle <oracle-address> \
   --network sepolia

   • Replace <gateway-address> with the actual address of the gateway you'll be using.
   • Replace <oracle-address> with the actual deployed address of your BaseFeePerGasOracle contract.

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Example Output

When you run the BaseFeePerGasOracle:execAndReadBaseFeePerGas command, you might see output similar to the following:

exec transaction sent: 0x335ffaab8033ca9c343f22f36e1d869464f8fe541450cda85df77f9e941152a8
Agent not processed yet, waiting ...
Agent not processed yet, waiting ...
Agent not processed yet, waiting ...
Waiting for the root hash update ...
Waiting for the root hash update ...
Waiting for the root hash update ...
readBaseFeePerGas transaction sent: 0xd355e97d6bb33ea55930ce8385f217ba81341df0e7848951fd865084e409c1ff
Waiting for the receipt ...
baseFeePerGas: 2726551007n