Software, written in Rust, used by WOA bridge validators to faciliate proof-of-authority based bridging of WOA native coins to tokens on another Vapory-based blockchain. The validators work with the WOA bridge contracts to convert ether on one chain into the same amount of VRC20 tokens on the other and back. This software was designed to work in conjunction with the following projects. Current compatability is unknown. * WOA Bridge UI * WOA Bridge Smart Contracts * WOA Bridge Monitoring service * WOA Bridge Deployment scripts
The bridge connects two chains (home and foreign). When a user deposits ether into the bridge contract contract on home they get the same amount of VRC20 tokens on foreign, and they
can convert them back as well.
Although the WOA bridge was initially based on the Parity Bridge, it was re-worked to include: * support of a gas price oracle introduced; * RPC is used instead of IPC; * sending of bridge approvals enhanced, increasing performance dramatically; * error handling improved to be compatible with Linux systemd facility; * bridge configuration parameters are fetched from bridge contracts so they don't need to be synchronized among several bridge instances; * bridge contracts were segregated into the separate project and their deployment is independent from the Rust side of the bridge. Now bridge contracts: * are separate from VRC20 * are upgradable; you don't need to re-configure bridge instances and DApps to use new version of contracts * allow a set of validators to be changed without neeeding to re-deploy thebridge contracts
Requires rust and cargo: installation instructions. Requires solc to be in $PATH: installation
instructions. Assuming you've cloned the bridge (git clone git@github.com:poanetwork/poa-bridge.git), run cd
woa-bridge make and install ../target/release/bridge in your $PATH.
bridge --config config.toml --database db.toml - --config - location of the configuration file. configuration file must exist - --database - location of the database file.
Bridge forces TLS for RPC connections by default. However, in some limited scenarios (like local testing), this might be undesirable. In this case, you can use the
--allow-insecure-rpc-endpoints option to allow non-TLS endpoints to be used. Ensure, however, that this option is not going to be used in production.
| Code | Meaning | ------|----------------------| 0 | Success | 1 | Unknwon error | 2 | I/O error | 3 | Shutdown requested | 4 | Insufficient funds | 5 | Gas too low | 6 | Gas price is too | low | 7 | Nonce reused | | 10 | Cannot connect | 11 | Connection lost | 12 | Bridge crashed | 20 | RPC error |
toml keystore = "/path/to/keystore" [home] account = "0x006e27b6a72e1f34c626762f3c4761547aff1421" password = "home_password.txt" rpc_host = "http://localhost" rpc_port = 8545
required_confirmations = 0 poll_interval = 5 request_timeout = 60 default_gas_price = 1_000_000_000 # 1 GWEI [foreign] account = "0x006e27b6a72e1f34c626762f3c4761547aff1421" password =
"foreign_password.txt" rpc_host = "http://localhost" rpc_port = 9545 required_confirmations = 8 poll_interval = 15 request_timeout = 60 gas_price_oracle_url = "https://gasprice.poa.network"
gas_price_speed = "instant" gas_price_timeout = 10 default_gas_price = 10_000_000_000 # 10 GWEI [authorities] [transactions] deposit_relay = { gas = 300000 } withdraw_relay = { gas = 300000
}
withdraw_confirm = { gas = 300000 }
keystore - path to a keystore directory with JSON keys
home/foreign.account - authority address on the home (required) - home/foreign.password - path to the file containing a password for the validator's account (to decrypt the key
from the keystore) - home/foreign.rpc_host - RPC host (required) - home/foreign.rpc_port - RPC port (defaults to 8545) - home/foreign.required_confirmations - number of
confirmations required to consider transaction final on home (default: 12) - home/foreign.poll_interval - specify how often home node should be polled for changes (in seconds,
default: 1) - home/foreign.request_timeout - specify request timeout (in seconds, default: 3600) - home/foreign.gas_price_oracle_url - the URL used to query the current
gas-price for the home and foreign nodes, this service is known as the gas-price Oracle. This config option defaults to None if not supplied in the User's config TOML file. If this config
value is None, no Oracle gas-price querying will occur, resulting in the config value for home/foreign.default_gas_price being used for all gas-prices. -
home/foreign.gas_price_timeout - the number of seconds to wait for an HTTP response from the gas price oracle before using the default gas price. Defaults to 10 seconds. -
home/foreign.gas_price_speed - retrieve the gas-price corresponding to this speed when querying from an Oracle. Defaults to fast. The available values are: "instant", "fast",
"standard", and "slow". - home/foreign.default_gas_price - the default gas price (in WEI) used in transactions with the home or foreign nodes. The default_gas_price is used when the
Oracle cannot be reached. The default value is 15_000_000_000 WEI (ie. 15 GWEI). - home/foreign.concurrent_http_requests - the number of concurrent HTTP requests allowed in-flight
(default: 64)
transaction.deposit_relay.gas - specify how much gas should be consumed by deposit relay - transaction.withdraw_confirm.gas - specify how much gas should be consumed by withdraw
confirm - transaction.withdraw_relay.gas - specify how much gas should be consumed by withdraw relay
toml home_contract_address = "0x49edf201c1e139282643d5e7c6fb0c7219ad1db7" foreign_contract_address = "0x49edf201c1e139282643d5e7c6fb0c7219ad1db8" checked_deposit_relay = 120
checked_withdraw_relay = 121 checked_withdraw_confirm = 121 all fields are required - home_contract_address - address of the bridge contract on home chain -
foreign_contract_address - address of the bridge contract on foreign chain - checked_deposit_relay - number of the last block for which an authority has relayed deposits to the foreign
- checked_withdraw_relay - number of the last block for which an authority has relayed withdraws to the home - checked_withdraw_confirm - number of the last block for which an authority
has confirmed withdraw