How To On Near Protocol

1. deploy MCS contract

You can use below command to deploy MCS contract.

# configure some parameters first
MASTER_ACCOUNT=      # the master account to create MCS account
MCS_ACCOUNT=         # MCS contract account to create
CLIENT_ACCOUNT=      # MAP light client contract account
MAP_BRIDGE_ADDRESS=  # MCS contract address on MAP blockchain
WNEAR_ACCOUNT=       # "wrap.testnet" for testnet, "wrap.near" for mainnet 
NEAR_CHAIN_ID=       # Near blockchain ID
MCS_WASM_FILE=       # path to the MCS contract wasm file
INIT_ARGS_MCS='{
              "map_light_client": "'$CLIENT_ACCOUNT'",
              "map_bridge_address": "'$MAPO_BRIDGE_ADDRESS'",
              "wrapped_token": "'$WNEAR_ACCOUNT'",
              "near_chain_id": '$NEAR_CHAIN_ID'
            }'
            
echo "creating MCS contract account"
near create-account $MCS_ACCOUNT --masterAccount $MASTER_ACCOUNT --initialBalance 40

echo "deploying mcs contract"
near deploy --accountId $MCS_ACCOUNT --wasmFile $MCS_WASM_FILE

echo "initializing mcs contract"
near call $MCS_ACCOUNT init "$INIT_ARGS_MCS" --accountId $MASTER_ACCOUNT --gas 80000000000000

2. manage MCS token and transfer out MCS token

2.1 deploy MCS token and set metadata

MCS_TOKEN_NAME="usdt"  # the MCS token you want to deploy
MCS_TOKEN=$MCS_TOKEN_NAME.$MCS_ACCOUNT  # the MCS token contract address
DECIMALS=24            # the MCS token decimal

echo "deploying $MCS_TOKEN_NAME contract"
near call $MCS_ACCOUNT deploy_mcs_token '{"address": "'$MCS_TOKEN_NAME'"}'  --accountId $MASTER_ACCOUNT --deposit 10 --gas 80000000000000

echo "set decimal metadata of token $MCS_TOKEN to $DECIMALS"
near call $MCS_ACCOUNT set_metadata '{"address": "'$$MCS_TOKEN'", "decimals": '$DECIMALS'}'  --accountId $MCS_ACCOUNT --gas 80000000000000

2.2 add target chain for the MCS token to transfer to

TO_CHAIN=34434  # target chain ID

echo "adding $MCS_TOKEN to_chain $TO_CHAIN to mcs contract"
near call $MCS_ACCOUNT add_mcs_token_to_chain '{"token": "'$MCS_TOKEN'", "to_chain": '$TO_CHAIN'}' --accountId $MCS_ACCOUNT

echo "getting mcs token list from mcs contract"
near view $MCS_ACCOUNT get_mcs_tokens '{}'

2.3 transfer out some amount (if someone has already transferred in some amount of the MCS token)

You can see the amount changes before and after the MCS token is transferred.

FROM=                                                                          # sender address on NEAR blockchain
TO="[46,120,72,116,221,179,44,215,151,93,104,86,91,80,148,18,165,181,25,244]"  # the receiver address in bytes on target blockchain
AMOUNT=150000000000000000000000

echo "before transfer out, get account $FROM balance of token $MCS_TOKEN"
near view $MCS_TOKEN ft_balance_of '{"account_id":"'$FROM'"}'

echo "transfer out $AMOUNT $MCS_TOKEN token from $FROM to $TO on chain $TO_CHAIN"
near call $MCS_ACCOUNT transfer_out_token '{"token":"'$MCS_TOKEN'", "to":'$TO', "amount":"'$AMOUNT'", "to_chain":'$TO_CHAIN'}' --accountId $FROM --gas 60000000000000

echo "after transfer out, get account $FROM balance of token $MCS_TOKEN"
near view $MCS_TOKEN ft_balance_of '{"account_id":"'$FROM'"}'

2.4 remove target chain to disable transfer to

echo "removing $MCS_TOKEN to_chain $TO_CHAIN from mcs contract"
near call $MCS_ACCOUNT remove_mcs_token_to_chain '{"token": "'$MCS_TOKEN'", "to_chain": '$TO_CHAIN'}' --accountId $MCS_ACCOUNT

3. manage fungible token and transfer out fungible token

The difference between MCS tokens and fungible tokens is that the MCS contract has the privilege to mint/burn MCS tokens, but the fungible tokens are tokens deployed by others and already exists on NEAR blockchain.

3.1 add target chain for the fungible token to transfer to

TO_CHAIN=34434            # target chain ID
FT_TOKEN="wrap.testnet"   # fungible token contract address

echo "adding $FT_TOKEN to_chain $TO_CHAIN to mcs contract"
near call $MCS_ACCOUNT add_fungible_token_to_chain '{"token": "'$FT_TOKEN'", "to_chain": '$TO_CHAIN'}' --accountId $MCS_ACCOUNT --gas 150000000000000

echo "getting fungible token list from mcs contract"
near view $MCS_ACCOUNT get_fungible_tokens '{}'

3.2 transfer out some amount

You can see the amount changes before and after the fungible token is transferred.

FROM=                                                                          # sender address on NEAR blockchain
TO="[46,120,72,116,221,179,44,215,151,93,104,86,91,80,148,18,165,181,25,244]"  # the receiver address in bytes on target blockchain

echo "before transfer out, get account $FROM balance of token $FT_TOKEN"
near view $FT_TOKEN ft_balance_of '{"account_id":"'$FROM'"}'

echo "transfer out $AMOUNT $FT_TOKEN token from $FROM to $TO on chain $TO_CHAIN"
near call $FT_TOKEN ft_transfer_call '{"receiver_id":"'$MCS_ACCOUNT'", "amount":"'$AMOUNT'", "memo": "", "msg": "{\"typ\": 0, \"to\": '$TO', \"to_chain\": '$TO_CHAIN'}"}' --accountId $FROM --depositYocto 1 --gas 60000000000000

echo "after transfer out, get account $FROM balance of token $FT_TOKEN"
near view $FT_TOKEN ft_balance_of '{"account_id":"'$FROM'"}'

3.3 remove target chain to disable transfer to

echo "removing $FT_TOKEN to_chain $TO_CHAIN from mcs contract"
near call $MCS_ACCOUNT remove_fungible_token_to_chain '{"token": "'$FT_TOKEN'", "to_chain": '$TO_CHAIN'}' --accountId $MCS_ACCOUNT

4. manage native token (NEAR) and transfer out native token

4.1 add target chain for the native token to transfer to

TO_CHAIN=34434            # target chain ID

echo "adding native token to_chain $TO_CHAIN to mcs contract"
near call $MCS_ACCOUNT add_native_to_chain '{"to_chain": '$TO_CHAIN'}' --accountId $MCS_ACCOUNT --gas 150000000000000

echo "getting native token list from mcs contract"
near view $MCS_ACCOUNT get_native_token_to_chains '{}'

4.2 transfer out some amount

You can see the amount changes before and after the native token is transferred.

FROM=                                                                          # sender address on NEAR blockchain
TO="[46,120,72,116,221,179,44,215,151,93,104,86,91,80,148,18,165,181,25,244]"  # the receiver address in bytes on target blockchain

echo "before transfer out, get state of account $FROM"
near state $FROM

echo "transfer out $AMOUNT Yocto NEAR from $FROM to $TO on chain $TO_CHAIN"
near call $MCS_ACCOUNT transfer_out_native '{ "to":'$TO', "to_chain": '$TO_CHAIN'}' --accountId $FROM --depositYocto $AMOUNT --gas 100000000000000

echo "after transfer out, get state of account $FROM"
near state $FROM

4.3 remove target chain to disable transfer to

echo "removing native token to_chain $TO_CHAIN from mcs contract"
near call $MCS_ACCOUNT remove_native_to_chain '{ "to_chain": '$TO_CHAIN'}' --accountId $MCS_ACCOUNT