EpochController.sol

The EpochController contract is a critical component for managing and tracking epochs in a blockchain-based system. Epochs are defined as fixed intervals of blocks and are used for various time-based operations, such as staking, reward distribution, and lock periods. This contract provides administrators the ability to configure epoch parameters and query epoch-related information in a decentralized manner.

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Key Features

1. Epoch Management:

   • Tracks the current epoch and calculates the start of the next epoch.

   • Allows modification of epoch-related parameters like length, lock periods, and reward delays.

2. Admin-Restricted Modifications:

   • All configuration changes can only be performed by accounts with the DEFAULT_ADMIN_ROLE.

3. Parameter Validations:

   • Ensures epoch parameters fall within specified minimum and maximum bounds to maintain system stability.

4. Event Emission:

   • Emits events whenever epoch parameters are updated, enabling off-chain monitoring and integration.

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Key Parameters

Public Constants

• MIN_EPOCH_LENGTH / MAX_EPOCH_LENGTH: Minimum and maximum allowed blocks per epoch.

• MIN_EPOCH_LOCK / MAX_EPOCH_LOCK: Bounds for the minimum number of epochs tokens can be locked.

• MIN_REWARD_DELAY / MAX_REWARD_DELAY: Bounds for the delay in epochs before rewards can be claimed.

State Variables

• epochLength: The number of blocks in an epoch.

• firstEpochBlock: The block number of the first epoch.

• minEpochsLocked: Minimum number of epochs tokens are locked.

• epochRewardDelay: Number of epochs before rewards are claimable.

• epochCheckpoint: The current epoch checkpoint number.

• epochCheckpointBlock: Block number when the last checkpoint was updated.

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Key Functions

Constructor

Sets the initial values for the epoch parameters and validates them against the defined bounds.

Parameters:

• _epochLength: Number of blocks in an epoch.

• _firstEpochBlock: Block number of the first epoch. If zero, it defaults to the next epoch block.

• _minEpochsLocked: Minimum number of epochs tokens are locked.

• _epochRewardDelay: Number of epochs before rewards are claimable.

Emits:

• EpochRewardDelayUpdated

• MinEpochsLockedUpdated

• EpochLengthUpdated

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Epoch Parameter Setters

setEpochLength(uint256 _epochLength)

• Updates the number of blocks per epoch.

• Reverts if the new epoch length is outside the allowed range or if reducing the epoch length in the current epoch.

Emits:

• EpochLengthUpdated

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setMinEpochsLocked(uint256 _minEpochsLocked)

• Updates the minimum number of epochs tokens are locked.

• Reverts if the new value is outside the allowed range.

Emits:

• MinEpochsLockedUpdated

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setEpochRewardDelay(uint256 _epochRewardDelay)

• Updates the reward delay in epochs.

• Reverts if the new value is outside the allowed range.

Emits:

• EpochRewardDelayUpdated

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Epoch Queries

nextEpochBlock()

• Returns the block number of the next epoch based on the current block and configured parameters.

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epochNumber()

• Returns the current epoch number based on the current block, epochLength, and epochCheckpoint.

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Access Control

The contract uses OpenZeppelin's AccessControl for role-based access management.

Roles:

• DEFAULT_ADMIN_ROLE:

  • Has the authority to update epoch parameters.

  • Assigned to the deploying account during contract initialization.

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Events

• EpochLengthUpdated(uint256 epochLength) Emitted when the epoch length is updated.

• MinEpochsLockedUpdated(uint256 minEpochsLocked) Emitted when the minimum epochs lock parameter is updated.

• EpochRewardDelayUpdated(uint256 epochRewardDelay) Emitted when the epoch reward delay parameter is updated.

Usage Examples

Initialization

EpochController epochController = new EpochController(
    100,        // epochLength (blocks)
    1000000,    // firstEpochBlock
    10,         // minEpochsLocked
    5           // epochRewardDelay
);

Querying Epoch Information

uint256 currentEpoch = epochController.epochNumber();
uint256 nextEpochStartBlock = epochController.nextEpochBlock();

This contract is designed to be a robust and flexible controller for epoch-based systems, enabling precise control over time-sensitive operations in decentralized environments.