# StateChannel
# Overview
The contact for Pay-as-you-go service for Indexer and Consumer. The consumer is not only a account, but also a contract
# ChannelStatus
enum ChannelStatus {
Finalized,
Open,
Terminating
}
# ChannelState
struct ChannelState {
enum StateChannel.ChannelStatus status;
address indexer;
address consumer;
uint256 total;
uint256 spent;
uint256 expiredAt;
uint256 terminatedAt;
bytes32 deploymentId;
bool terminateByIndexer;
}
# QueryState
struct QueryState {
uint256 channelId;
uint256 spent;
bool isFinal;
bytes indexerSign;
bytes consumerSign;
}
# STATES
# settings
Settings info
contract ISettings settings
# terminateExpiration
The expiration of the terminate. Default is 24 * 60 * 60 = 86400s
uint256 terminateExpiration
# channels
The states of the channels
mapping(uint256 => struct StateChannel.ChannelState) channels
# channelPrice
The price of the channel
mapping(uint256 => uint256) channelPrice
# EVENTS
# ChannelOpen
Emitted when open a channel for Pay-as-you-go service
event ChannelOpen(uint256 channelId, address indexer, address consumer, uint256 total, uint256 price, uint256 expiredAt, bytes32 deploymentId, bytes callback)
# ChannelExtend
Emitted when extend the channel
event ChannelExtend(uint256 channelId, uint256 expiredAt)
# ChannelFund
Emitted when deposit more amount to the channel
event ChannelFund(uint256 channelId, uint256 total)
# ChannelCheckpoint
Emitted when indexer send a checkpoint to claim the part-amount
event ChannelCheckpoint(uint256 channelId, uint256 spent)
# ChannelTerminate
Emitted when consumer start a terminate on channel to finalize in advance
event ChannelTerminate(uint256 channelId, uint256 spent, uint256 terminatedAt, bool terminateByIndexer)
# ChannelFinalize
Emitted when finalize the channel
event ChannelFinalize(uint256 channelId, uint256 total, uint256 remain)
# ChannelLabor
Emitted when Settle the channel with new state
event ChannelLabor(bytes32 deploymentId, address indexer, uint256 amount)
# FUNCTIONS
# initialize
Initialize the contract, setup the terminateExpiration
function initialize(contract ISettings _settings) external
| Name | Type | Description |
|---|---|---|
| _settings | contract ISettings | settings contract address |
# setSettings
Update setting state.
function setSettings(contract ISettings _settings) external
| Name | Type | Description |
|---|---|---|
| _settings | contract ISettings | ISettings contract |
# setTerminateExpiration
Update the expiration of the terminate
function setTerminateExpiration(uint256 expiration) external
| Name | Type | Description |
|---|---|---|
| expiration | uint256 | terminate expiration time in seconds |
# channel
Get the channel info
function channel(uint256 channelId) external view returns (struct StateChannel.ChannelState)
| Name | Type | Description |
|---|---|---|
| channelId | uint256 | channel id |
Return: struct StateChannel.ChannelState -> ChannelState channel info
# open
Indexer and Consumer open a channel for Pay-as-you-go service. It will lock the amount of consumer and start a new channel. Need consumer approve amount first. If consumer is contract, use callback to call paid
function open(uint256 channelId, address indexer, address consumer, uint256 amount, uint256 price, uint256 expiration, bytes32 deploymentId, bytes callback, bytes indexerSign, bytes consumerSign) external
| Name | Type | Description |
|---|---|---|
| channelId | uint256 | channel id |
| indexer | address | indexer address |
| consumer | address | consumer address |
| amount | uint256 | SQT amount deposit in channel |
| price | uint256 | |
| expiration | uint256 | channel expiration time in seconds |
| deploymentId | bytes32 | deployment id |
| callback | bytes | callback info for contract, if consumer not a contract, set null: "0x" |
| indexerSign | bytes | indexer's signature |
| consumerSign | bytes | consumer's signature |
# extend
Extend the channel expiredAt
function extend(uint256 channelId, uint256 preExpirationAt, uint256 expiration, bytes indexerSign, bytes consumerSign) external
| Name | Type | Description |
|---|---|---|
| channelId | uint256 | channel id |
| preExpirationAt | uint256 | previous ExpirationAt timestamp |
| expiration | uint256 | Extend tiem in seconds |
| indexerSign | bytes | indexer's signature |
| consumerSign | bytes | consumer's signature |
# fund
Deposit more amount to this channel. need consumer approve amount first
function fund(uint256 channelId, uint256 preTotal, uint256 amount, bytes callback, bytes sign) external
| Name | Type | Description |
|---|---|---|
| channelId | uint256 | channel id |
| preTotal | uint256 | previous toal amount |
| amount | uint256 | SQT amount to deposit |
| callback | bytes | callback info for contract |
| sign | bytes | the signature of the consumer |
# checkpoint
Indexer can send a checkpoint to claim the part-amount. This amount will send to RewardDistributer for staking
function checkpoint(struct StateChannel.QueryState query) external
| Name | Type | Description |
|---|---|---|
| query | struct StateChannel.QueryState | the state of the channel |
# terminate
When indexer/consumer what to finalize in advance, can start a terminate. If terminate success, consumer will claim the rest of the locked amount. Indexer can respond to this terminate within the time limit
function terminate(struct StateChannel.QueryState query) external
| Name | Type | Description |
|---|---|---|
| query | struct StateChannel.QueryState | the state of the channel |
# respond
Indexer respond the terminate by send the service proof after the terminate
function respond(struct StateChannel.QueryState query) external
| Name | Type | Description |
|---|---|---|
| query | struct StateChannel.QueryState | the state of the channel |
# claim
When terminate success (Overdue did not respond) or expiration, consumer can claim the amount
function claim(uint256 channelId) external
| Name | Type | Description |
|---|---|---|
| channelId | uint256 | channel id |
PRIVATE FUNCTIONS
# _checkStateSign
Check the signature of the hash with channel info
function _checkStateSign(uint256 channelId, bytes32 payload, bytes indexerSign, bytes consumerSign) private view
# _checkSign
Check the signature of the hash with given addresses
function _checkSign(bytes32 payload, bytes sign, address checkSigner, bool isIndexer) private view
# _settlement
Settlement the new state
function _settlement(struct StateChannel.QueryState query, bool finalize) private
# _finalize
Finalize the channel
function _finalize(uint256 channelId) private
# _isContract
Determine the input address is contract or not
function _isContract(address _addr) private view returns (bool)