UnifiRouter.sol
Primary Uses - The uTrade V2 Router is the 'brain' of uTrade. The router finds the optimal path for exchanging one token for another. Whenever a trade is made, your wallet sends funds to the router address. The router will then carry out as many transactions as necessary to acquire the desired token. The router also handles adding liquidity to liquidity pools, and sending the corresponding LP tokens to liquidity providers.
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uTrade V2 Router (Solidity) | |
uTrade V2 Router Interface as JSON | |
uTrade V2 Router Interface as Typescript | |
Import statement codeblock (when available) | ​ |
function factory() external pure returns (address);
A call to the
factory
function returns the address of the current Factory used by uTrade v2. The current factory address for uTrade V2 on Ethereum is 0x08e7974CacF66C5a92a37c221A15D3c30C7d97e0
.function WETH() external pure returns (address);
A call to the
WETH
function returns the address of Wrapped ETH (WETH) on Ethereum. As this address does not change, it will always return 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2
.function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
A call to the
quote
function returns the amount of tokenB that will be received for an amount of tokenA. This can be used to calculate the exchange rate between two tokens without factoring in slippage or fees. By entering the amount of tokenA, the total amount of reserves of tokenA as reserveA, and the total amount of reserves of tokenB as reserveB, the call will return the equivalent amount of tokenB.function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut, uint fee) external pure returns (uint amountOut);
A call to the
getAmountOut
function with the amount of the token being sent will return the maximum amount of a token to be received, accounting for fees and the total amount of reserves.function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut, uint fee) external pure returns (uint amountIn);
A call to the
getAmountIn
function with the amount of the token you wish to receive will return the minimum amount required of the token you wish to send, accounting for fees and the total amount of reserves.function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
A call to the
getAmountsOut
function with the amount of the token being sent will return the maximum amount to be received of multiple different tokens. By entering multiple LP addresses in the address array, the function will return the maximum amount of each token that will be received. A call to this function uses the getReserves
function from UnifiPair.sol to determine the reserves of the liquidity pool. Then, it calls the getAmountOut
function to determine the amount of each token in the array that will be received for the amountIn value of a token.function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
A call to the
getAmountsIn
function with the desired amount of the token to be received will return the minimum amount required to be sent of multiple tokens. By entering multiple LP addresses in the address array, the function will return the minimum amount of each token that will need to be sent to receive the desired amount of a token. A call to this function uses the getReserves
function from UnifiPair.sol to determine the reserves of the liquidity pool. Then, it calls the getAmountIn
function to determine the amount of each token in the array that will need to be sent for the amountOut value of a token. function addLiquidity(
address tokenA,
address tokenB,
uint amountADesired,
uint amountBDesired,
uint amountAMin,
uint amountBMin,
address to,
uint deadline
) external returns (uint amountA, uint amountB, uint liquidity);
The
addLiquidity
function adds the two tokens that make up the liquidity pool - tokenA and tokenB - at the proper ratio based on the reserves of the pool. For example, if the pool contains 3000 USDT / 2 ETH, a user's liquidity will be added at the ratio of 1500 USDT to 1 ETH, provided there is no price movements in the pair between when the user broadcasts the transaction to when it is mined. In the event of a price movement, the amountADesired, amountBDesired, amountAMin, and amountBMin act as a security measure against an adverse price movement. After the liquidity is added, the function sends the corresponding LP tokens to the sender.In the case of a pool not existing for the two assets, one will be created using UnifiFactory.sol at the ratio of the assets supplied.
Parameter | Type | Description |
tokenA | address | Token address of the first asset in the token pair. |
tokenB | address | Token address of the second asset in the token pair. |
amountADesired | uint | The amount of tokenA to be added to liquidity if the value of tokenA goes down in comparison to tokenB. |
amountBDesired | uint | The amount of tokenB to be added to liquidity if the value of tokenB goes down in comparison to tokenA. |
amountAMin | uint | Sets the minimum amount of tokenA that can added to the pool before the transaction reverts. This acts as a safeguard.
|
amountBMin | uint | Sets the minimum amount of tokenB that can added to the pool before the transaction reverts. This acts as a safeguard. ​
|
to | address | The address to which the LP tokens for the uTrade V2 pool will be sent. |
deadline | uint | The UNIX timestamp for which this transaction must be completed. If the transaction is mined after this deadline, the transaction will revert. |
Parameter | Type | Description |
amountA | uint | The exact amount of tokenA that was sent to the pool. |
amountB | uint | The exact amount of tokenB that was sent to the pool. |
liquidity | uint | The exact amount of liquidity tokens minted and sent to the address provided in the to parameter. |
function addLiquidityETH(
address token,
uint amountTokenDesired,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external payable returns (uint amountToken, uint amountETH, uint liquidity);
The
addLiquidityEth
function is similar to the addLiquidity
function except it accounts for one token being a native asset. In the case of Ethereum, this native asset would be ETH. This function will convert ETH to WETH, will pair that WETH with the supplied other token, and add the liquidity to the pool. This function will add at the ideal ratio based on when the transaction is mined.
In the case of a pool not existing for WETH and the token provided, one will be created using UnifiFactory.sol at the ratio of the assets supplied.- This function requires a msg.value with the amount of ETH to be added.
- The msg.value acts as the amountETHDesired. As in, if the ratio between ETH and the token being paired with it change, this is the number of ETH that will be added to the pool.
- Any leftover ETH is returned to the msg.sender address.
Parameter | Type | Description |
token | address | The address of the supplied token for the liquidity pool. In other words, the asset that ETH is paired with. |
amountTokenDesired | uint | The amount of the supplied token to be added to liquidity if the value of token goes down in comparison to ETH. |
(amountETHDesired) msg.value | uint | Sent as the msg.value, the amount of ETH to be added to liquidity if the value of ETH goes down in comparison to token. |
amountTokenMin | uint | Sets the minimum amount of the supplied token that can added to the pool before the transaction reverts. This acts as a safeguard. ​
|
amountETHMin | uint | ​ Sets the minimum amount of ETH that can added to the pool before the transaction reverts. This acts as a safeguard. ​
|
to | address | The address to which the LP tokens for the uTrade V2 pool will be sent. |
deadline | uint | The UNIX timestamp for which this transaction must be completed. If the transaction is mined after this deadline, the transaction will revert. |
Parameter | Type | Description |
amountToken | uint | The exact amount of the supplied token sent to the pool. |
amountETH | uint | The exact amount of ETH converted to WETH, and then added to the pool. |
liquidity | uint | The exact amount of liquidity tokens minted and sent to the address provided in the to parameter. |
function removeLiquidity(
address tokenA,
address tokenB,
uint liquidity,
uint amountAMin,
uint amountBMin,
address to,
uint deadline
) external returns (uint amountA, uint amountB);
The
removeLiquidity
function removes the two tokens that make up liquidity from a pool. In other words, this function is used when the pool consists of two ERC-20 tokens.- In the event one of the assets is paired with ETH, ETH will have been wrapped and paired with WETH (Wrapped Ether). If the user wishes to withdraw WETH instead of withdrawing as ETH, this function should be used instead of
removeLiquidityETH
.
Parameter | Type | Description |
tokenA | address | Token address of the first asset in the pair. |
tokenB | address | Token address of the second asset in the pair. |
liquidity | uint | The amount of liquidity tokens to be redeemed and removed. |
amountAMin | uint | Sets the minimum amount of tokenA to be removed from the the pool. This acts as a safeguard against removing liquidity during a spike in value. If the removed amount falls below this value, the transaction reverts. |
amountBMin | uint | Sets the minimum amount of tokenB to be removed from the the pool. This acts as a safeguard against removing liquidity during a spike in value. If the removed amount falls below this value, the transaction reverts. |
to | address | The address to where the redeemed tokens will be sent. |
deadline | uint | The UNIX timestamp for which this transaction must be completed. If the transaction is mined after this deadline, the transaction will revert. |
Parameter | Title | Description |
amountA | uint | The exact amount of tokenA sent to the address provided in the to parameter. |
amountB | uint | The exact amount of tokenB sent to the address provided in the to parameter. |
function removeLiquidityETH(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external returns (uint amountToken, uint amountETH);
The
removeLiquidityETH
function removes ETH as well as the corresponding paired token in the liquidity pool. In other words, this function is used when the pool consists of WETH and an ERC-20 token.- In the event one of the assets is paired with ETH, ETH has been wrapped into WETH (Wrapped Ether). This function will unwrap the WETH as the liquidity removed. If the user wishes to withdraw WETH instead of withdrawing as ETH, the
removeLiquidity
function should be used.
Parameter | Type | Description |
token | address | Token address of the ERC-20 asset in the pair. |
liquidity | uint | The amount of liquidity tokens to be redeemed and removed. |
amountTokenMin | uint | Sets the minimum amount of token to be removed from the the pool. This acts as a safeguard against removing liquidity during a spike in value. If the removed amount falls below this value, the transaction reverts. |
amountETHMin | uint | Sets the minimum amount of ETH to be removed from the pool. This acts as a safeguard against removing liquidity during a spike in value. If the removed amount falls below this value, the transaction reverts. |
to | address | The address to where ETH and token will be sent. |
deadline | uint | The UNIX timestamp for which this transaction must be completed. If the transaction is mined after this deadline, the transaction will revert. |
Parameter | Value | Description |
amountToken | uint | The exact amount of token sent to the address provided in the to parameter. |
amountETH | uint | The exact amount of ETH sent to the address provided in the to parameter. |
function removeLiquidityWithPermit(
address tokenA,
address tokenB,
uint liquidity,
uint amountAMin,
uint amountBMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountA, uint amountB);
The
removeLiquidityWithPermit
functions removes the two tokens that make up liquidity from a pool. In other words, this function is used when the pool consists of two ERC-20 tokens. This function operates similarly to the removeLiquidity
function with the added benefit of not requiring pre-approvals using permit.- In the event one of the assets is paired with ETH, ETH will have been wrapped and paired with WETH (Wrapped ETH). If the user wishes to withdraw WETH instead of withdrawing as ETH, this function should be used instead of
removeLiquidityETHWithPermit
.
Parameter | Type | Description |
tokenA | address | Token address of the first asset in the pair. |
tokenB | address | Token address of the second asset in the pair. |
liquidity | uint | The amount of liquidity tokens to be redeemed and removed. |
amountAMin | uint | Sets the minimum amount of tokenA to be removed from the the pool. This acts as a safeguard against removing liquidity during a spike in value. If the removed amount falls below this value, the transaction reverts. |
amountBMin | uint | Sets the minimum amount of tokenB to be removed from the the pool. This acts as a safeguard against removing liquidity during a spike in value. If the removed amount falls below this value, the transaction reverts. |
to | address | The address to where the redeemed tokens will be sent. |
deadline | uint | The UNIX timestamp for which this transaction must be completed. If the transaction is mined after this deadline, the transaction will revert. |
approveMax | bool | Sets a true or false value on if approval amount in the signature is for liquidity or for uint(-1). |
v | uint8 | The v value of the permit. This is one of the three values that makes up the approval signature. |
r | bytes32 | The r value of the permit. This is one of the three values that makes up the approval signature. |
s | bytes32 | The s value of the permit. This is one of the three values that makes up the approval signature. |
Parameter | Title | Description |
amountA | uint | The exact amount of tokenA sent to the address provided in the to parameter. |
amountB | uint | The exact amount of tokenB sent to the address provided in the to parameter. |
function removeLiquidityETHWithPermit(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountToken, uint amountETH);
The
removeLiquidityETHWithPermit
function removes ETH as well as the corresponding paired token in the liquidity pool. In other words, this function is used when the pool consists of WETH and a ERC-20 token. This function operates similarly to the removeLiquidityETH
function with the added benefit of not requiring pre-approvals using permit.- In the event one of the assets is paired with ETH, ETH has been wrapped into WETH (Wrapped Ether). This function will unwrap the WETH as the liquidity removed. If the user wishes to withdraw WETH instead of withdrawing as ETH, the
removeLiquidityWithPermit
function should be used.
Parameter | Type | Description |
token | address | Token address of the ERC-20 asset in the pair. |
liquidity | uint | The amount of liquidity tokens to be redeemed and removed. |
amountTokenMin | uint | Sets the minimum amount of token to be removed from the the pool. This acts as a safeguard against removing liquidity during a spike in value. If the removed amount falls below this value, the transaction reverts. |
amountETHMin | uint | Sets the minimum amount of ETH to be removed from the the pool. This acts as a safeguard against removing liquidity during a spike in value. If the removed amount falls below this value, the transaction reverts. |
to | address | The address to where ETH and token will be sent. |
deadline | uint | The UNIX timestamp for which this transaction must be completed. If the transaction is mined after this deadline, the transaction will revert. |
v | uint8 | The v value of the permit. This is one of the three values that makes up the approval signature. |
r | bytes32 | The r value of the permit. This is one of the three values that makes up the approval signature. |
s | bytes32 | The s value of the permit. This is one of the three values that makes up the approval signature. |
Parameter | Value | Description |
amountToken | uint | The exact amount of token sent to the address provided in the to parameter. |
amountETH | uint | The exact amount of ETH sent to the address provided in the to parameter. |
function removeLiquidityETHSupportingFeeOnTransferTokens(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external returns (uint amountETH);
The
removeLiquidityETHSupportingFeeOnTransferTokens
function is similar to the removeLiquidityETH
function, and contains the same call parameters. This function removes ETH as well as the corresponding paired token in the liquidity pool. In other words, this function is used when the pool consists of WETH and a ERC-20 token. However, this function allows for fee on transfer tokens, such as PAXG, to be used on uTrade.
Parameter | Type | Description |
token | address | Token address of the ERC-20 asset in the pair. |
liquidity | uint | The amount of liquidity tokens to be redeemed and removed. |
amountTokenMin | uint | Sets the minimum amount of token to be removed from the the pool. This acts as a safeguard against removing liquidity during a spike in value. If the removed amount falls below this value, the transaction reverts. |
amountETHMin | uint | Sets the minimum amount of ETH to be removed from the the pool. This acts as a safeguard against removing liquidity during a spike in value. If the removed amount falls below this value, the transaction reverts. |
to | address | The address to where ETH and the paired token will be sent. |
deadline | uint | The UNIX timestamp for which this transaction must be completed. If the transaction is mined after this deadline, the transaction will revert. |
Parameter | Value | Description |
amountETH | uint | The exact amount of ETH sent to the address provided in the to parameter. Note that the amountToken parameter is not returned. The amount of fee on transfer that a token may have is not available prior to transaction. |
function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountETH);
The
removeLiquidityETHWithPermitSupportingFeeOnTransferTokens
function is similar to the removeLiquidityETHWithPermit
function. This function removes ETH as well as the corresponding paired token in the liquidity pool. In other words, this function is used when the pool consists of WETH and an ERC-20 token. This function operates similarly to the removeLiquidityETHfunction
with the added benefit of not requiring pre-approvals using permit. In addition, this function allows for fee on transfer tokens, such as PAXG, to be used on uTrade. Parameter | Type | Description |
token | address | Token address of the ERC-20 asset in the pair. |
liquidity | uint | The amount of liquidity tokens to be redeemed and removed. |
amountTokenMin | uint | Sets the minimum amount of token to be removed from the the pool. This acts as a safeguard against removing liquidity during a spike in value. If the removed amount falls below this value, the transaction reverts. |
amountETHMin | uint | Sets the minimum amount of ETH to be removed from the the pool. This acts as a safeguard against removing liquidity during a spike in value. If the removed amount falls below this value, the transaction reverts. |
to | address | The address to where ETH and token will be sent. |
deadline | uint | The UNIX timestamp for which this transaction must be completed. If the transaction is mined after this deadline, the transaction will revert. |
v | uint8 | The v value of the permit. This is one of the three values that makes up the approval signature. |
r | bytes32 | The r value of the permit. This is one of the three values that makes up the approval signature. |
s | bytes32 | The s value of the permit. This is one of the three values that makes up the approval signature. |
Parameter | Value | Description |
amountETH | uint | The exact amount of ETH sent to the address provided in the to parameter. Note that the amountToken parameter is not returned. The amount of fee on transfer that a token may have is not available prior to transaction. |
function swapExactTokensForTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external returns (uint[] memory amounts);
The
swapExactTokensForTokens
function sends an exact amount of tokens for the maximum amount of another token. Parameter | Type | Description |
amountIn | uint | The amount of tokens being sent to swap into another token |
amountOutMin | uint | Sets the minimum amount of the desired token to receive. This acts as a safeguard against removing liquidity during a spike in value. If the amount to be received falls below this value, the transaction reverts. |
path | address[] calldata | The pathway to change one token to another, consisting of an array of addresses. Each token must have an existing liquidity pool, as well as have liquidity.
The path represents the pathway from one token to another. If a pair exists for the two tokens you wish to exchange, this will contain two values inside of an array. However, if there is no direct pair, multiple addresses may be required. |
to | address | The address to where the desired token will be sent. |
deadline | uint | The UNIX timestamp for which this transaction must be completed. If the transaction is mined after this deadline, the transaction will revert. |
Parameter | Type | Description |
amounts | uint[] memory | The exact amount of tokens sent into the swap, as well as the exact return amount of all subsequent swaps. |
function swapTokensForExactTokens(
uint amountOut,
uint amountInMax,
address[] calldata path,
address to,
uint deadline
) external returns (uint[] memory amounts);
The
swapTokensForExactTokens
function sends the minimum amount of tokens for the exact amount of another token. Parameter | Type | Description |
amountOut | uint | The exact amount of the desired tokens to be received. |
amountInMax | uint | Sets the maximum amount of token to be sent in. This acts as a safeguard against removing liquidity during a spike in value. If the amount to be sent rises above this value, the transaction reverts. |
path | address[] calldata | The pathway to change one token to another, consisting of an array of addresses. Each token must have an existing liquidity pool, as well as have liquidity.
The path represents the pathway from one token to another. If a pair exists for the two tokens you wish to exchange, this will contain two values inside of an array. However, if there is no direct pair, multiple addresses may be required. |
to | address | The address to where the desired token will be sent. |
deadline | uint | The UNIX timestamp for which this transaction must be completed. If the transaction is mined after this deadline, the transaction will revert. |
Parameter | Type | Description |
amounts | uint[] memory | The exact amount of tokens sent into the swap, as well as the exact return amount of all subsequent swaps. |
function swapExactETHForTokens(
uint amountOutMin,
address[] calldata path,
address to,
uint deadline)
external
payable
returns (uint[] memory amounts);
The
swapExactETHForTokens
function sends an exact amount of ETH for a desired token.Parameter | Type | Description |
(amountIn) msg.value | uint | Sent as the msg.value, the amount of ETH to be swapped. |
amountOutMin | uint | Sets the minimum amount of the desired token to receive. This acts as a safeguard against removing liquidity during a spike in value. If the amount to be received falls below this value, the transaction reverts. |
path | address[] calldata | The pathway to change one token to another, consisting of an array of addresses. Each token must have an existing liquidity pool, as well as have liquidity.
The path represents the pathway from one token to another. If a pair exists for the two tokens you wish to exchange, this will contain two values inside of an array. However, if there is no direct pair, multiple addresses may be required. ​ As the first swap is swapping ETH to WETH, the first address must be WETH. |
to | address | The address to where the desired token will be sent. |
deadline | uint | The UNIX timestamp for which this transaction must be completed. If the transaction is mined after this deadline, the transaction will revert. |
Parameter | Type | Description |
amounts | uint[] memory | The exact amount of ETH sent into the swap, as well as the exact return amount of all subsequent swaps. |
function swapTokensForExactETH(
uint amountOut,
uint amountInMax,
address[] calldata path,
address to,
uint deadline)
external
returns (uint[] memory amounts);
The
swapTokensForExactETH
function sends an amount of tokens for an exact amount of ETH.Parameter | Type | Description |
amountOut | uint | The exact amount of the ETH to be received. |
amountInMax | uint | Sets the maximum amount of token to be sent in. This acts as a safeguard against removing liquidity during a spike in value. If the amount to be sent rises above this value, the transaction reverts. |
path | address[] calldata | The pathway to change one token to another, consisting of an array of addresses. Each token must have an existing liquidity pool, as well as have liquidity.
The path represents the pathway from one token to another. If a pair exists for the two tokens you wish to exchange, this will contain two values inside of an array. However, if there is no direct pair, multiple addresses may be required. |
to | address | The address to where the desired token will be sent. |
deadline | uint | The UNIX timestamp for which this transaction must be completed. If the transaction is mined after this deadline, the transaction will revert. |
Parameter | Type | Description |
amounts | uint[] memory | The exact amount of tokens sent into the swap, as well as the exact amount of all subsequent swaps. |
function swapExactTokensForETH(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline)
external
returns (uint[] memory amounts);
The
swapExactTokensForETH
function sends an exact amount of tokens for ETH.Parameter | Type | Description |
amountIn | uint | The amount of tokens being sent to swap into ETH. |
amountOutMin | uint | Sets the minimum amount of the ETH to receive. This acts as a safeguard against removing liquidity during a spike in value. If the amount to be received falls below this value, the transaction reverts. |
path | address[] calldata | The pathway to change one token to another, consisting of an array of addresses. Each token must have an existing liquidity pool, as well as have liquidity.
The path represents the pathway from one token to another. If a pair exists for the two tokens you wish to exchange, this will contain two values inside of an array. However, if there is no direct pair, multiple addresses may be required. |
to | address | The address to where the desired token will be sent. |
deadline | uint |