Liquid Newton Contract Interface
Autonity Liquid Newton Contract functions
The Liquid Newton contract is deployed by the Autonity contract in response to validator registration. It implements the Liquid Newton token for that validator, and handles the distribution of staking rewards to all delegators.
The address of the Liquid Newton contract for a given validator can be determined by the information returned from the Autonity contract getValidator method (see here for details of how to query this using Autonity CLI).
Liquid Newton tokens implement the ERC20 interface, and so all ERC20 calls are implemented. The following public methods are also available for handling the reward distribution and querying Liquid Newton balances.
Autonity implements a ‘pull-based’ model for staking rewards where delegators must manually retrieve their rewards.
The validator treasury receives commission rewards automatically epoch end when the Autonity Contract [finalize()(/reference/api/aut/op-prot/#finalize) function is invoked to finalize the last block of the epoch.
claimTreasuryATN() is provided for a failure scenario if finalize() fails to send ATN rewards to the validator treasury end of epoch. To prevent reward loss the protocol tracks ATN rewards for the treasury and the treasury can claim them by calling claimTreasuryATN(). A validator operator can check if there are commission rewards to claim by calling getTreasuryUnclaimedATN() from the validator treasury address.
The claimRewards() function is for stake delegators who don’t receive their rewards automatically.
Some Usage and Examples illustrate using the Liquid Newton Contracts’ generated ABI and the aut tool’s contract command to call the Liquid Newton Contract functions. See aut contract call --help.
Usage and Examples assume the path to the ABI file has been set in aut’s configuration file .autrc. The contract .abi files are generated when building the client from source and can be found in your autonity installation directory at ./params/generated/Liquid.abi. Alternatively, you can generate the ABI using the abigen cmd utility if you built from source (See Install Autonity, Build from source code).
You will need to specify the validator’s Liquid Newton contract address. This can be retrieved using the aut command aut validator info - for usage see Autonity Contract Interface and getValidator().
claimRewards
Computes the total ATN rewards owed to the caller from a specific validator stake delegation, and sends the appropriate amount of Auton to the caller’s staking wallet account.
- The claim rewards function is used by any stake delegator to claim ATN staking rewards, i.e. for delegated or self-bonded stake.
- Ir returns rewards for a designated validator. If the caller has stake delegations to multiple validators, then
claimRewards()will need to be called for each stake delegation.
The aut validator claim-rewards command uses this function. Usage details and examples are given in the “Claiming staking rewards” section.
claimTreasuryATN
Used by a validator operator to claim ATN rewards accrued by the validator from the validator commission charged on stake delegations. The rewards are sent to the validator treasury account.
Constraint checks are applied:
- the caller is the validator
treasuryaddress.
Parameters
None.
Response
None.
Event
None.
Usage
The claimTreasuryATN() function in the Liquid Newton Contract Interface is not currently supported by aut.
You can interact with the contract using the aut contract command group. See aut contract tx -h for how to submit a transaction calling the interface function.
getTreasuryUnclaimedATN
Used by a validator operator to return the total unclaimed ATN rewards accrued by the validator via the commission charged on delegated stake. The rewards are sent to the validator treasury account.
The rewards can be claimed and sent to the validator’s treasury by the validator operator calling claimTreasuryATN().
Parameters
None.
Response
None.
Event
None.
Usage
The getTreasuryUnclaimedATN() function in the Liquid Newton Contract Interface is not currently supported by aut.
You can interact with the contract using the aut contract command group. See aut contract call -h for how to submit a transaction calling the interface function.
balanceOf (ERC-20)
Note that the ERC-20 balanceOf() will return the sum of locked and unlocked balances of LNTN in the contract. The locked and unlocked balances can be returned individually using lockedBalanceOf() and unlockedBalanceOf().
lockedBalanceOf
Queries the contract and returns the amount of locked Liquid Newton held by a stake delegator’s account.
Parameters
| Field | Datatype | Description |
|---|---|---|
delegator |
address |
the account address of the Liquid Newton holder for which the locked balance amount is requested |
Response
| Field | Datatype | Description |
|---|---|---|
amount |
uint256 |
the account balance for Liquid Newton in a locked state |
Usage
aut contract call --address lockedBalanceOf delegatorExample
aut contract call --address 0x109f93893af4c4b0afc7a9e97b59991260f98313 lockedBalanceOf 0xF47FDD88C8f6F80239E177386cC5AE3d6BCdEeEa
0unclaimedRewards
Returns the total ATN rewards owed to a given account. Computes the total ATN rewards owed to the caller for a specific validator stake delegation.
This function is used by the aut validator unclaimed-rewards command of aut. Further details are given in the “Claiming staking rewards” section.
unlockedBalanceOf
Queries the contract and returns the amount of unlocked Liquid Newton held by a stake delegator’s account.
Parameters
| Field | Datatype | Description |
|---|---|---|
delegator |
address |
the account address of the Liquid Newton holder for which the unlocked balance amount is requested |
Response
| Field | Datatype | Description |
|---|---|---|
amount |
uint256 |
the account balance for Liquid Newton in an unlocked state |
Usage
aut contract call --address unlockedBalanceOf delegatorExample
aut contract call --address 0x109f93893af4c4b0afc7a9e97b59991260f98313 unlockedBalanceOf 0xF47FDD88C8f6F80239E177386cC5AE3d6BCdEeEa
0