Mini - A Minimal Cosmos SDK Chain with Checkers Game

This repository contains a working Cosmos SDK chain that implements a checkers game module. It uses minimal modules and serves as a starting point for building your own chain with game functionality.

Overview

Minid is built with the latest version of Cosmos-SDK and includes:

• Basic chain functionality
• Checkers game module
• Account management
• Token handling (mini tokens)

Prerequisites

• Go 1.21 or later (installation guide)
• Configure your environment:

  export PATH="$PATH:/usr/local/go/bin:$(/usr/local/go/bin/go env GOPATH)/bin"

Installation & Setup

1. Clone and build the chain:

git clone https://github.com/cybertronprime/chain-minimal.git
cd chain-minimal
make install   # Install the minid binary
make init      # Initialize the chain

2. Start the chain:

minid start --minimum-gas-prices="0mini"

Playing Checkers

Create a New Game

minid tx checkers create-game <game-id> \
    <black-player-address> \
    <red-player-address> \
    --from <creator-address> \
    --gas auto \
    --gas-prices 0mini \
    --chain-id demo \
    --yes

Example:

minid tx checkers create-game myGame1 \
    mini1dyr9fktej5af9mq3vdwv76uy9dvptkaxqnqm24 \
    mini10gl9v6utc7hz6dflasdaw3d29z9368ynphh683 \
    --from alice --yes

Query Game Status

minid query checkers get-game <game-id>

Example:

minid query checkers get-game myGame1

Example output:

Game:
  black: mini1dyr9fktej5af9mq3vdwv76uy9dvptkaxqnqm24
  board: '*b*b*b*b|b*b*b*b*|*b*b*b*b|********|********|r*r*r*r*|*r*r*r*r|r*r*r*r*'
  red: mini10gl9v6utc7hz6dflasdaw3d29z9368ynphh683
  turn: b

Export Chain State

To export the current state of the chain:

minid export

This will output the entire chain state including:

• Account balances
• Game states
• Validator information
• Module parameters

Key Management

After initialization, two accounts are created:

1. Alice (with 10,000,000 mini tokens)
2. Bob (with 1,000 mini tokens)

Keep the generated mnemonics safe - they are required to recover these accounts.

Troubleshooting

1. If minid is not found after installation:

   • Verify your $PATH configuration
   • Run which minid to check the installation
   • Try re-running make install

2. If you get a gas price error:

   • Always include --gas-prices in your transactions
   • Or set minimum gas prices in ~/.minid/config/app.toml

3. If a game query returns empty:

   • Verify the game ID is correct
   • Ensure the transaction to create the game was successful
   • Check the chain is running and synced

Development

The chain includes several key components:

• Custom checkers module
• Cosmos SDK core modules (auth, bank, staking)
• Minimal dependency set for optimal performance

Testing

Running Tests

To run all tests in the chain:

To run specific module tests (e.g., checkers module):

go test ./x/checkers/... -v

Useful Links

• Cosmos-SDK Documentation
• Cosmos Network
• Tendermint Core

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the terms of the MIT license.