Simple Counter Template - Cartesi Coprocessor

This repo contains an end-to-end template that demonstrates a simple counter running on Cartesi Co-processor's stack. The backend of the Coprocessor dApp is implemented in 4 different languages: JavaScript, Python, Rust, and Go. You can pick any language and extend the template to your own Coprocessor logic.

The UI template is implemented with React and Wagmi starter kit.

How does it work?

A user can connect their wallet to the frontend and increment the counter. The frontend will send a transaction to the caller contract, which will then call the co-processor to increment the counter. The co-processor will then return the result to the on-chain contract, which will be reflected on the UI.

A data flow diagram is provided below to help you understand the flow of data between the frontend, the on-chain contract, and the co-processor.

Project Structure

• backend-cartesi-counter-js/ - Backend implementation in JavaScript.
• backend-cartesi-counter-py/ - Backend implementation in Python.
• backend-cartesi-counter-rs/ - Backend implementation in Rust.
• backend-cartesi-counter-go/ - Backend implementation in Go.
• contracts/ - Smart contract with custom dApp logic and function to issue task to the co-processor.
• ui-coprocessor-template/ - Frontend React application for reading the counter value and incrementing it.

Setup Instructions for Devnet

Below steps will assume that you've cloned this repo to your local machine and you already have Docker Desktop, Cartesi CLI and Foundry installed.

1. Install cartesi-coprocessor CLI

cartesi-coprocessor CLI will help us build, publish, deploy and run local environment with ease.

cargo install cartesi-coprocessor

2. Run the Coprocessor devnet environment

Before running the dApp, you need to have the Coprocessor devnet environment running. It will spin up a local operator in devnet mode that will host the dApp backend.

On your terminal, start the devnet environment:

cartesi-coprocessor start-devnet

You can open Docker Desktop to see the running containers and corresponding logs. DApp logs are visible in the cartesi-coprocessor-operator container.

To turn down the environment later, run:

cartesi-coprocessor stop-devnet

3. Build and Publish Backend Cartesi Machine

Open another terminal tab and cd into the desired backend folder Python, JavaScript, Rust, and Go.

Run the publish command for devnet:

cartesi-coprocessor publish --network devnet

At this point, you should see the machine hash by running:

cartesi-coprocessor address-book

4. Deploy CounterCaller Smart Contract

To deploy the contract, cd into the contracts folder and run the following command:

cartesi-coprocessor deploy --contract-name CounterCaller --network devnet --constructor-args <task_issuer_address> <machine_hash>

NOTE: You can get the task_issuer_address and machine_hash from the address-book command as shown in the previous step.

Copy the deployed contract address you get from above command and save it for later use in the frontend interaction.

5. Run Frontend Application

Navigate to the frontend folder and follow steps in the README

The frontend will be available at http://localhost:3000

License

MIT