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Running the Cartesi Coprocessor

Follow this guide to set up Foundry, run the Cartesi Coprocessor devnet, and interact with the Coprocessor.

Ensure Foundry is installed and accessible:
forge --version

If you don't have Foundry installed, please refer to the installation guide and set it up before proceeding.

Step 1: Start your devnet​

The devnet is a simulated environment where developers can test their applications or smart contracts before deploying them to a mainnet (the primary live network). The CLI uses the foundry's anvil devnet by default.

Run the Cartesi Coprocessor Devnet Environment:

cartesi-coprocessor start-devnet

To stop and clean up the environment later, use:

cartesi-coprocessor stop-devnet
Test Accounts

You might need a few wallets to test your dApp. Here are some that already have assets on the devnet for your testing purposes.

Account #0: 0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266 (10000 ETH) Private Key: 0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80
Account #1: 0x70997970c51812dc3a010c7d01b50e0d17dc79c8 (10000 ETH) Private Key: 0x59c6995e998f97a5a0044966f0945389dc9e86dae88c7a8412f4603b6b78690d
Account #2: 0x3c44cdddb6a900fa2b585dd299e03d12fa4293bc (10000 ETH) Private Key: 0x5de4111afa1a4b94908f83103eb1f1706367c2e68ca870fc3fb9a804cdab365a
Using the template

You can optionally clone the base contract template for reference and implementation:

git clone https://github.com/Mugen-Builders/coprocessor-base-contract

Step2: Install the Base Contract​

Install the base contract in your project:

forge install https://github.com/Mugen-Builders/coprocessor-base-contract --no-commit

Step3: Import and Inherit the Base Contract​

Add the base contract to your project:

import "cartesi-coprocessor-base-contract/BaseContract.sol";

contract MyContract is CoprocessorAdapter {
    constructor(address _taskIssuerAddress, bytes32 _machineHash)
        CoprocessorAdapter(_taskIssuerAddress, _machineHash)
    {}

    // Add your business logic here
}
Responses from the coprocessor

The handleNotice function in the CoprocessorAdapterSample.sol smart contract is triggered by notices sent from the Python application. It is invoked directly when the Coprocessor interacts with the smart contract.

Step 4: Get the important addresses​

cartesi-coprocessor address-book

This command prints a list of useful contacts and their addresses.

Retrieving important addresses

Running this command in the directory containing your Cartesi program and not the base directory or solidity contract directory also displays the machine hash of your program if your program has been built previously. It also contains the task issuer, which is the Coprocessor address your smart contract needs during the contract deployment step.

Step 5: Deploy the Smart Contract​

Deploys the solidity contract of your project to any specified network of your choice.

cartesi-coprocessor deploy --contract-name <contract name> --network devnet --constructor-args <arguments seperated by single space>

For the base examples provided, the arguments will be Coprocessor Address and Machine Hash, both of which can be obtained from the address-book command on the previous step.

cartesi-coprocessor deploy --contract-name MyContract --network devnet --constructor-args <Coprocessor Address> <Machine Hash>
Run in the correct directory

This should be run in the directory for your solidity contract not the base directory.

Multiple Deploys

Each successful deployment is logged and stored in a separate directory called deployment_history.