Minimal implementation for CW20 Token (CosmWasm)

Minimal implementation of CW20 token on CosmWasm. Supported functionalities:

Transfer tokens
Mint tokens (from only fixed address)
Burn tokens

Guide

This guideline is based on official CosmWasm doc.

Prepare

Requirement: Step-by-step
- wasmd
- Rust with wasm32 build target
- jq (tool to parse json response when execute smart contract)
Create your wallet (should create more than 1 wallet for testing transfer)
```
wasmd keys add {your-wallet-name}
```

Export those variables to use later

# We gonna use malaga testnet
export CHAIN_ID="malaga-420"  
export TESTNET_NAME="malaga-420"
export RPC="https://rpc.malaga-420.cosmwasm.com:443"
export API="https://api.malaga-420.cosmwasm.com"
export FAUCET="https://faucet.malaga-420.cosmwasm.com"

export FEE_DENOM="umlg"
export STAKE_DENOM="uand"
export BECH32_HRP="wasm"
export WASMD_VERSION="v0.27.0"
export CONFIG_DIR=".wasmd"
export BINARY="wasmd"

export NODE=(--node $RPC)
export TXFLAG=($NODE --chain-id $CHAIN_ID --gas-prices 0.25$FEE_DENOM --gas auto --gas-adjustment 1.3)

Add fund to your wallet (to deploy and run smart contract, called gas in Ethereuum)

JSON=$(jq -n --arg addr $(wasmd keys show -a {your-wallet-name}) '{"denom":"umlg","address":$addr}') && curl -X POST --header "Content-Type: application/json" --data "$JSON" https://faucet.malaga-420.cosmwasm.com/credit

# Quick check your balance
wasmd query bank balances $(wasmd keys show -a {your-wallet-name}) $NODE

Compile & Deploy & Interact

Update minter address in src/state.rs to yours
Compile to .wasm file (You can also use docker for more optimized here)
```
RUSTFLAGS='-C link-arg=-s' cargo wasm
```

Deploy

# Upload your smart contract
RES=$(wasmd tx wasm store {your-path-to-wasm-file} --from wallet $TXFLAG -y --output json -b block)

# Get code_id of your smart contract
CODE_ID=$(echo $RES | jq -r '.logs[0].events[-1].attributes[0].value')

Initialize

# InstantiateMsg (change this on your preference)
INIT_MSG='{"name": "THONG COIN","symbol": "CUCMO","cap": "1000000","total_supply": "500000"}'

# Initialize contract with InstantiateMsg
wasmd tx wasm instantiate $CODE_ID "$INIT_MSG" --from {your-wallet-name} --label {your-contract-label} $TXFLAG -y --no-admin

# Check list of contract that initialized before
wasmd query wasm list-contract-by-code $CODE_ID $NODE --output json

# Extract the contract address to use later
CONTRACT=$(wasmd query wasm list-contract-by-code $CODE_ID $NODE --output json | jq -r '.contracts[-1]')

Interact

# Wallet name that have tokens
WALLET_FROM={your-wallet-name}

# Wallet name that you want to transfer to
WALLET_TO={another-wallet-name}

# TransferMsg (change this on your preference)
TRANSFER='{"transfer":{"recipient":"'$(wasmd keys show -a $WALLET_TO)'","amount":"55"}}'
echo $TRANSFER

# Execute TRANSFER command on smart contract
wasmd tx wasm execute $CONTRACT "$TRANSFER" --from $WALLET_FROM $TXFLAG -y

# QueryBalanceMsg (change this on your preference)
BALANCE='{"balance": {"address": "'$(wasmd keys show -a $WALLET_FROM)'"}}'

# Execute QUERY balance command on smart contract
wasmd query wasm contract-state smart $CONTRACT "$BALANCE" $NODE --output json

thethongngu/minimal-cw20-token

Minimal implementation for CW20 Token (CosmWasm)

Guide

Prepare

Compile & Deploy & Interact