Silo

ISilo
Silo is the main component of the protocol. It implements lending logic, manages and isolates risk, acts as a vault for assets, and performs liquidations. Each Silo is composed of the unique asset for which it was created (ie. UNI) and bridge assets (ie. ETH and SiloDollar). There may be multiple bridge assets at any given time.
Main Silo contact that inherits from Base contract. It implements all user/UI facing methods.
Methods
ASSET_DECIMAL_POINTS
function ASSET_DECIMAL_POINTS() external view returns (uint256)
Returns
Name
Type
Description
_0
uint256
undefined
VERSION
function VERSION() external view returns (uint256)
It tells us which SiloRepository.siloFactory(version) created this Silo
Returns
Name
Type
Description
_0
uint256
undefined
accrueInterest
function accrueInterest(address _asset) external nonpayable
Function to update interests for _asset token since the last saved state
Parameters
Name
Type
Description
_asset
address
The address of the token to be updated
allSiloAssets
function allSiloAssets(uint256) external view returns (address)
Parameters
Name
Type
Description
_0
uint256
undefined
Returns
Name
Type
Description
_0
address
undefined
assetInterestData
function assetInterestData(address) external view returns (uint256 harvestedProtocolFees, uint256 protocolFees, uint64 interestRateTimestamp, enum IBaseSilo.AssetStatus status)
Parameters
Name
Type
Description
_0
address
undefined
Returns
Name
Type
Description
harvestedProtocolFees
uint256
undefined
protocolFees
uint256
undefined
interestRateTimestamp
uint64
undefined
status
enum IBaseSilo.AssetStatus
undefined
assetStorage
function assetStorage(address _asset) external view returns (struct IBaseSilo.AssetStorage)
Get asset storage data
Parameters
Name
Type
Description
_asset
address
asset address
Returns
Name
Type
Description
_0
IBaseSilo.AssetStorage
AssetStorage struct
borrow
function borrow(address _asset, uint256 _amount) external nonpayable
Borrow _amount of _asset tokens from the Silo to msg.sender
Parameters
Name
Type
Description
_asset
address
The address of the token to borrow
_amount
uint256
The amount of the token to borrow
borrowFor
function borrowFor(address _asset, address _borrower, address _receiver, uint256 _amount) external nonpayable
Router function to borrow _amount of _asset tokens from the Silo for the _receiver
Parameters
Name
Type
Description
_asset
address
The address of the token to borrow
_borrower
address
The address of the debt tokens receiver
_receiver
address
The address of the asset receiver
_amount
uint256
The amount of the token to borrow
borrowPossible
function borrowPossible(address _asset, address _borrower) external view returns (bool)
Check if borrowing an asset for given account is possible
Borrowing an asset that has been already deposited (and vice versa) is disallowed
Parameters
Name
Type
Description
_asset
address
asset we want to deposit
_borrower
address
borrower address
Returns
Name
Type
Description
_0
bool
true if asset can be borrowed by borrower
deposit
function deposit(address _asset, uint256 _amount, bool _collateralOnly) external nonpayable
Deposit _amount of _asset tokens from msg.sender to the Silo
Parameters
Name
Type
Description
_asset
address
The address of the token to deposit
_amount
uint256
The amount of the token to deposit
_collateralOnly
bool
True if depositing collateral only
depositFor
function depositFor(address _asset, address _depositor, uint256 _amount, bool _collateralOnly) external nonpayable
Router function to deposit _amount of _asset tokens to the Silo for the _depositor
Parameters
Name
Type
Description
_asset
address
The address of the token to deposit
_depositor
address
The address of the recipient of collateral tokens
_amount
uint256
The amount of the token to deposit
_collateralOnly
bool
True if depositing collateral only
depositPossible
function depositPossible(address _asset, address _depositor) external view returns (bool)
Check if depositing an asset for given account is possible
Depositing an asset that has been already borrowed (and vice versa) is disallowed
Parameters
Name
Type
Description
_asset
address
asset we want to deposit
_depositor
address
depositor address
Returns
Name
Type
Description
_0
bool
true if asset can be deposited by depositor
flashLiquidate
function flashLiquidate(address[] _users, bytes _flashReceiverData) external nonpayable returns (address[] assets, uint256[][] receivedCollaterals, uint256[][] shareAmountsToRepay)
this methods does not requires to have tokens in order to liquidate user
during liquidation process, msg.sender will be notified once all collateral will be send to him msg.sender needs to be IFlashLiquidationReceiver
Parameters
Name
Type
Description
_users
address[]
array of users to liquidate
_flashReceiverData
bytes
this data will be forward to msg.sender on notification
Returns
Name
Type
Description
assets
address[]
array of all processed assets (collateral + debt, including removed)
receivedCollaterals
uint256[][]
seizedCollaterals[userId][assetId] => amount amounts of collaterals send to _flashReceiver
shareAmountsToRepay
uint256[][]
shareAmountsToRepaid[userId][assetId] => amount required amounts of debt to be repaid
getAssets
function getAssets() external view returns (address[] assets)
Returns all initialized (synced) assets of Silo including current and removed bridge assets
Returns
Name
Type
Description
assets
address[]
array of initialized assets of Silo
getAssetsWithState
function getAssetsWithState() external view returns (address[] assets, struct IBaseSilo.AssetStorage[] assetsStorage)
Returns all initialized (synced) assets of Silo including current and removed bridge assets with corresponding state
Returns
Name
Type
Description
assets
address[]
array of initialized assets of Silo
assetsStorage
IBaseSilo.AssetStorage[]
array of assets state corresponding to assets array
harvestProtocolFees
function harvestProtocolFees(address[] _assets) external nonpayable
harvest protocol fees from an array of assets
Parameters
Name
Type
Description
_assets
address[]
array of assets we want to harvest fees from
initAssetsTokens
function initAssetsTokens() external nonpayable
this is exposed only for test purposes, but it is safe to leave it like that
interestData
function interestData(address _asset) external view returns (struct IBaseSilo.AssetInterestData)
Get asset interest data
Parameters
Name
Type
Description
_asset
address
asset address
Returns
Name
Type
Description
_0
IBaseSilo.AssetInterestData
AssetInterestData struct
isSolvent
function isSolvent(address _user) external view returns (bool)
Calculates solvency of an account
Parameters
Name
Type
Description
_user
address
wallet address for which solvency is calculated
Returns
Name
Type
Description
_0
bool
true if solvent, false otherwise
repay
function repay(address _asset, uint256 _amount) external nonpayable
Repay _amount of _asset tokens from msg.sender to the Silo
Parameters
Name
Type
Description
_asset
address
The address of the token to repay
_amount
uint256
amount of asset to repay, includes interests
repayFor
function repayFor(address _asset, address _borrower, uint256 _amount) external nonpayable
Allows to repay in behalf of borrower to execute liquidation
Parameters
Name
Type
Description
_asset
address
The address of the token to repay
_borrower
address
The address of the user to have debt tokens burned
_amount
uint256
amount of asset to repay, includes interests
siloAsset
function siloAsset() external view returns (address)
Returns
Name
Type
Description
_0
address
undefined
siloRepository
function siloRepository() external view returns (contract ISiloRepository)
Get Silo Repository contract address
Returns
Name
Type
Description
_0
contract ISiloRepository
undefined
state
function state(address) external view returns (contract IShareToken collateralToken, contract IShareToken collateralOnlyToken, contract IShareToken debtToken, uint256 totalDeposits, uint256 collateralOnlyDeposits, uint256 totalBorrowAmount)
Parameters
Name
Type
Description
_0
address
undefined
Returns
Name
Type
Description
collateralToken
contract IShareToken
undefined
collateralOnlyToken
contract IShareToken
undefined
debtToken
contract IShareToken
undefined
totalDeposits
uint256
undefined
collateralOnlyDeposits
uint256
undefined
totalBorrowAmount
uint256
undefined
syncBridgeAssets
function syncBridgeAssets() external nonpayable
Synchronize current bridge assets with Silo
This function needs to be called on Silo deployment to setup all assets for Silo. It needs to be called every time a bridged asset is added or removed. When bridge asset is removed, depositing and borrowing should be disabled during asset sync.
utilizationData
function utilizationData(address _asset) external view returns (struct IBaseSilo.UtilizationData data)
helper method for InterestRateModel calculations
Parameters
Name
Type
Description
_asset
address
undefined
Returns
Name
Type
Description
data
IBaseSilo.UtilizationData
undefined
withdraw
function withdraw(address _asset, uint256 _amount, bool _collateralOnly) external nonpayable
Withdraw _amount of _asset tokens from the Silo to msg.sender
Parameters
Name
Type
Description
_asset
address
The address of the token to withdraw
_amount
uint256
The amount of the token to withdraw
_collateralOnly
bool
True if withdrawing collateral only deposit
withdrawFor
function withdrawFor(address _asset, address _depositor, address _receiver, uint256 _amount, bool _collateralOnly) external nonpayable
Router function to withdraw _amount of _asset tokens from the Silo for the _depositor
Parameters
Name
Type
Description
_asset
address
The address of the token to withdraw
_depositor
address
The address of the collateral tokens source account
_receiver
address
The address of the asset receiver
_amount
uint256
The amount of the token to withdraw
_collateralOnly
bool
True if withdrawing collateral only deposit
Events
Borrow
event Borrow(address indexed asset, address indexed user, uint256 amount)
Emitted on asset borrow
Parameters
Name
Type
Description
asset indexed
address
undefined
user indexed
address
undefined
amount
uint256
undefined
Deposit
event Deposit(address indexed asset, address indexed depositor, uint256 amount, bool collateralOnly)
Emitted when deposit is made
Parameters
Name
Type
Description
asset indexed
address
undefined
depositor indexed
address
undefined
amount
uint256
undefined
collateralOnly
bool
undefined
Liquidate
event Liquidate(address indexed asset, address indexed user, uint256 shareAmountRepaid, uint256 seizedCollateral)
Emitted on user liquidation
Parameters
Name
Type
Description
asset indexed
address
undefined
user indexed
address
undefined
shareAmountRepaid
uint256
undefined
seizedCollateral
uint256
undefined
Repay
event Repay(address indexed asset, address indexed user, uint256 amount)
Emitted on asset repay
Parameters
Name
Type
Description
asset indexed
address
undefined
user indexed
address
undefined
amount
uint256
undefined
Withdraw
event Withdraw(address indexed asset, address indexed depositor, address indexed receiver, uint256 amount, bool collateralOnly)
Emitted when withdraw is made
Parameters
Name
Type
Description
asset indexed
address
undefined
depositor indexed
address

Name	Type	Description
harvestedProtocolFees	uint256	undefined
protocolFees	uint256	undefined
interestRateTimestamp	uint64	undefined
status	enum IBaseSilo.AssetStatus	undefined

Name	Type	Description
_asset	address	The address of the token to borrow
_amount	uint256	The amount of the token to borrow

Name	Type	Description
_asset	address	asset we want to deposit
_borrower	address	borrower address

Name	Type	Description
_asset	address	The address of the token to deposit
_amount	uint256	The amount of the token to deposit
_collateralOnly	bool	True if depositing collateral only

Name	Type	Description
_users	address[]	array of users to liquidate
_flashReceiverData	bytes	this data will be forward to msg.sender on notification

Name	Type	Description
assets	address[]	array of all processed assets (collateral + debt, including removed)
receivedCollaterals	uint256[][]	seizedCollaterals[userId][assetId] => amount amounts of collaterals send to `_flashReceiver`
shareAmountsToRepay	uint256[][]	shareAmountsToRepaid[userId][assetId] => amount required amounts of debt to be repaid

Name	Type	Description
assets	address[]	array of initialized assets of Silo
assetsStorage	IBaseSilo.AssetStorage[]	array of assets state corresponding to `assets` array

Name	Type	Description
_asset	address	The address of the token to repay
_amount	uint256	amount of asset to repay, includes interests

Name	Type	Description
collateralToken	contract IShareToken	undefined
collateralOnlyToken	contract IShareToken	undefined
debtToken	contract IShareToken	undefined
totalDeposits	uint256	undefined
collateralOnlyDeposits	uint256	undefined
totalBorrowAmount	uint256	undefined

Name	Type	Description
_asset	address	The address of the token to withdraw
_amount	uint256	The amount of the token to withdraw
_collateralOnly	bool	True if withdrawing collateral only deposit

Name	Type	Description
asset `indexed`	address	undefined
user `indexed`	address	undefined
amount	uint256	undefined