openethereum/miner/src/service_transaction_checker.rs

58 lines
2.1 KiB
Rust
Raw Normal View History

// Copyright 2017 Parity Technologies (UK) Ltd.
// This file is part of Parity.
// Parity is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Parity is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Parity. If not, see <http://www.gnu.org/licenses/>.
//! A service transactions contract checker.
use ethereum_types::Address;
use transaction::SignedTransaction;
use types::ids::BlockId;
use_contract!(service_transaction, "ServiceTransaction", "res/service_transaction.json");
const SERVICE_TRANSACTION_CONTRACT_REGISTRY_NAME: &'static str = "service_transaction_checker";
/// A contract calling interface.
pub trait ContractCaller {
/// Returns address of contract from the registry, given it's name
fn registry_address(&self, name: &str) -> Option<Address>;
/// Executes a contract call at given block.
fn call_contract(&self, BlockId, Address, Vec<u8>) -> Result<Vec<u8>, String>;
}
/// Service transactions checker.
#[derive(Default)]
pub struct ServiceTransactionChecker {
contract: service_transaction::ServiceTransaction,
}
impl ServiceTransactionChecker {
/// Checks if service transaction can be appended to the transaction queue.
pub fn check(&self, client: &ContractCaller, tx: &SignedTransaction) -> Result<bool, String> {
assert!(tx.gas_price.is_zero());
let address = client.registry_address(SERVICE_TRANSACTION_CONTRACT_REGISTRY_NAME)
.ok_or_else(|| "contract is not configured")?;
trace!(target: "txqueue", "Checking service transaction checker contract from {}", address);
self.contract.functions()
.certified()
.call(tx.sender(), &|data| client.call_contract(BlockId::Latest, address, data))
.map_err(|e| e.to_string())
}
}