Pallet Token Gateway

This allows standalone chains or parachains make asset transfers to and from EVM token gateway deployments.

Overview

The Pallet allows the AdminOrigin configured in pallet-ismp to dispatch calls for setting token gateway addresses.

Adding to Runtime

The first step is to implement the pallet config for the runtime.

use frame_support::parameter_types;
use ismp::module::IsmpModule;
use ismp::router::IsmpRouter;

parameter_types! {
    // A constant that should represent the native asset id
    pub const NativeAssetId: u32 = 0; 
    // Set the correct precision for the native currency
    pub const Decimals: u8 = 12;
}

/// Should provide an account that is funded and can be used to pay for asset creation
pub struct AssetAdmin;

impl Get<AccountId> for AssetAdmin {
	fn get() -> AccountId {
		Treasury::account_id()
	}
}

impl pallet_token_gateway::Config for Runtime {
    // configure the runtime event
    type RuntimeEvent = RuntimeEvent;
    // Pallet Ismp 
    type Dispatcher = Ismp;
    // Pallet Assets
	type Assets = Assets;
    // Pallet balances
	type Currency = Balances;
    // AssetAdmin account
    type AssetAdmin = AssetAdmin;
    // The Native asset Id
	type NativeAssetId = NativeAssetId;
    // A type that provides a function for creating unique asset ids
    // A concrete implementation for your specific runtime is required
    type AssetIdFactory = ();
    // The precision of the native asset
    type Decimals = Decimals;
}

// Add the pallet to your ISMP router
#[derive(Default)]
struct Router;
impl IsmpRouter for Router {
    fn module_for_id(&self, id: Vec<u8>) -> Result<Box<dyn IsmpModule>, anyhow::Error> {
        let module = match id.as_slice() {
            id if TokenGateway::is_token_gateway(&id) => Box::new(TokenGateway::default()),
            _ => Err(Error::ModuleNotFound(id))?
        };
        Ok(module)
    }
}

Setting up

The pallet requires some setting up before the teleport function is available for use in the runtime.

1. Register your native assets directly on Hyperbridge by dispatching create_erc6160_asset.
2. Set token gateway addresses for the EVM chains of interest by dispatching the set_token_gateway_addresses extrinsic. These addresses are used to validate incoming messages.

Dispatchable Functions

• teleport - This function is used to bridge assets through Hyperbridge.
• set_token_gateway_addresses - This call allows the AdminOrigin origin to set the token gateway address for EVM chains.
• create_erc6160_asset - This call dispatches a request to Hyperbridge to create multi chain native assets on token gateway deployments
• update_erc6160_asset - This priviledged call dispatches a request to Hyperbridge to update multi chain native assets on token gateway deployments

License

This library is licensed under the Apache 2.0 License, Copyright (c) 2024 Polytope Labs.