Near Protocol Contract

MOS

Contract Address

Here to get MAPO mainnet and testnet MCS contract address.

Contract interface

impl MapCrossChainService {
    pub fn init(map_light_client: String, map_bridge_address: String, wrapped_token: String, near_chain_id: u128) -> Promise;

    pub fn version() -> &'static str;

    #[payable]
    pub fn transfer_in(&mut self, receipt_proof: ReceiptProof, index: usize) -> Promise;

    pub fn transfer_out_token(&mut self, token: String, to: Vec<u8>, amount: U128, to_chain: u128) -> Promise;

    #[payable]
    pub fn transfer_out_native(&mut self, to: Vec<u8>, to_chain: u128) -> Promise;

    #[payable]
    pub fn deposit_out_native(&mut self, to: Vec<u8>);

    #[payable]
    pub fn deploy_mcs_token(&mut self, name: String) -> Promise;

    pub fn is_used_event(&self, order_id: &CryptoHash) -> bool;

    pub fn set_metadata(
        &mut self,
        address: String,
        name: Option<String>,
        symbol: Option<String>,
        reference: Option<String>,
        reference_hash: Option<Base64VecU8>,
        decimals: Option<u8>,
        icon: Option<String>,
    ) -> Promise;

    pub fn controller(&self) -> Option<AccountId>;

    pub fn set_controller(&mut self, controller: AccountId);

    pub fn controller_or_self(&self) -> bool;

    pub fn get_mcs_tokens(&self) -> Vec<(String, HashSet<u128>)>;

    pub fn get_fungible_tokens(&self) -> Vec<(String, HashSet<u128>)>;

    pub fn get_native_token_to_chains(&self) -> HashSet<u128>;

    pub fn add_native_to_chain(&mut self, to_chain: u128);

    pub fn remove_native_to_chain(&mut self, to_chain: u128);

    pub fn add_mcs_token_to_chain(&mut self, token: String, to_chain: u128);

    pub fn remove_mcs_token_to_chain(&mut self, token: String, to_chain: u128);

    pub fn valid_mcs_token_out(&self, token: &String, to_chain: u128) -> bool;

    pub fn add_fungible_token_to_chain(&mut self, token: String, to_chain: u128) -> PromiseOrValue<()>;

    pub fn remove_fungible_token_to_chain(&mut self, token: String, to_chain: u128);

    pub fn valid_fungible_token_out(&self, token: &String, to_chain: u128) -> bool;
}

Interact with contract interface

transfer_in

Transfer from Mapo to Near based on the proof data and event. Must attach enough NEAR funds to cover for storage of the proof.

input parameters

parameter	type	comment
receipt_proof	ReceiptProof	the proof of one receipt
index	usize	the index of event among all the events in the receipt

transfer_out_token

Transfer out tokens to other blockchain.

input parameters

parameter	type	comment
token	String	NEAR account of the mcs token contract
to	Vec	the target account address on target blockchain
amount	U128	the amount of token to transfer out
to_chain	u128	the chain id of target blockchain

transfer_out_native

Transfer out native token to other blockchain.

input parameters

parameter	type	comment
to	Vec	the target account address on target blockchain
to_chain	u128	the chain id of target blockchain

deposit_out_native

Deposit out native token to MAP blockchain.

input parameters

parameter	type	comment
to	Vec	the target account address on MAP blockchain

Management Interface

init

Initialize the contract with configuration parameters.

input parameters

parameter	type	comment
map_light_client	String	NEAR account of the MAP light client contract
map_bridge_address	String	the address of the MCS contract on MAP blockchain, in hex
wrapped_token	String	NEAR account of the wrap near contract
near_chain_id	u128	the chain id of the near blockchain

version

Get the version info of the current MCS contract.

deploy_mcs_token

Deploy MCS token contract. The deployed token can be minted/burnt by MCS contract.

input parameters

parameter	type	comment
name	String	the name of MCS token, the full address of the token will be .

is_used_event

Check if the event is ussed or not.

input parameters

parameter	type	comment
order_id	&CryptoHash	the order id of the event

output parameters

type	comment
bool	true if the event is already used, false otherwise

set_metadata

Get the record information( validators, threshold and epoch) for the epecified epoch.

input parameters

parameter	type	comment
address	String	the contract address of the MCS token
name	Option	the human-readable name of the token
symbol	Option	the abbreviation, like wETH or AMPL
reference	Option	a link to a valid JSON file containing various keys offering supplementary details on the token
reference_hash	Option	the base64-encoded sha256 hash of the JSON file contained in the reference field
decimals	Option	used in frontends to show the proper significant digits of a token
icon	Option	a small image associated with this token

controller

Get the controller of the MCS contract.

output parameters

type	comment
Option	the controller account id of the MCS contract

set_controller

Set the controller of the MCS contract.

input parameters

parameter	type	comment
controller	AccountId	the controller account id of the MCS contract

controller_or_self

Check if the predecessor is controller or self.

output parameters

type	comment
bool	true if the predecessor is controller or self, false otherwise

get_mcs_tokens

Get all deployed MCS tokens and their target chains.

output parameters

type	comment
Vec<(String, HashSet)>	deployed MCS tokens and their target chains

get_fungible_tokens

Get all registered fungible tokens and their target chains.

output parameters

type	comment
Vec<(String, HashSet)>	registered fungible tokens and their target chains

get_native_token_to_chains

Get all registered native token target chains.

output parameters

type	comment
HashSet	registered native token target chains

add_native_to_chain

Add target chain for native token.

input parameters

parameter	type	comment
to_chain	u128	target chain id

remove_native_to_chain

Remove target chain for native token.

input parameters

parameter	type	comment
to_chain	u128	target chain id

add_mcs_token_to_chain

Allow the MCS token to be transfered to the target chain.

input parameters

parameter	type	comment
token	String	MCS token address
to_chain	u128	target chain id

remove_mcs_token_to_chain

Remove the target chain id from the allow list of the MCS token.

input parameters

parameter	type	comment
token	String	MCS token address
to_chain	u128	target chain id

valid_mcs_token_out

Check if the MCS token is allowed to be transfered to the target chain.

input parameters

parameter	type	comment
token	&String	MCS token address
to_chain	u128	target chain id

output parameters

type	comment
bool	true if target chain is allowed, false otherwise

add_fungible_token_to_chain

Allow the fungible token to be transfered to the target chain.

input parameters

parameter	type	comment
token	String	fungible token address
to_chain	u128	target chain id

remove_fungible_token_to_chain

Remove the target chain id from the allow list of the fungible token.

input parameters

parameter	type	comment
token	String	fungible token address
to_chain	u128	target chain id

valid_fungible_token_out

Check if the fungible token is allowed to be transfered to the target chain.

input parameters

parameter	type	comment
token	&String	MCS token address
to_chain	u128	target chain id

output parameters

type	comment
bool	true if target chain is allowed, false otherwise

Data structure

Here are some main data structure for map light client contract.

MapCrossChainService is the map cross chain service contract.

pub struct MapCrossChainService {
    /// The account of the map light client that we can use to prove
    pub map_client_account: AccountId,
    /// Address of the MAP bridge contract.
    pub map_bridge_address: Address,
    /// Set of created MCSToken contracts.
    pub mcs_tokens: UnorderedMap<String, HashSet<u128>>,
    /// Set of other fungible token contracts.
    pub fungible_tokens: UnorderedMap<String, HashSet<u128>>,
    /// Map of other fungible token contracts and their min storage balance.
    pub fungible_tokens_storage_balance: UnorderedMap<String, u128>,
    /// Map of token contracts and their decimals
    pub token_decimals: UnorderedMap<String, u8>,
    /// Set of other fungible token contracts.
    pub native_to_chains: HashSet<u128>,
    /// Hashes of the events that were already used.
    pub used_events: UnorderedSet<CryptoHash>,
    /// Public key of the account deploying the MCS contract.
    pub owner_pk: PublicKey,
    /// Balance required to register a new account in the MCSToken
    pub mcs_storage_transfer_in_required: Balance,
    // Wrap token for near
    pub wrapped_token: String,
    // Near chain id
    // FIXME: get from env?
    pub near_chain_id: u128,
    // Nonce to generate order id
    pub nonce: u128,
    /// Mask determining all paused functions
    paused: Mask,
}

ReceiptProof includes the proof and the receipt to prove.

pub struct ReceiptProof {
    // the block header where the receipt exists
    pub header: Header,
    // the aggregated G2 public key of the signed validators
    pub agg_pk: G2,
    // the receipt to prove
    pub receipt: Receipt,
    // the index of the receipt in the block
    pub key_index: Vec<u8>,
    // the proof to prove the existance of the above receipt
    pub proof: Vec<ProofEntry>,
}