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.

uTrade V2 Router Code / Interfaces

uTrade V2 Router (Solidity)
uTrade V2 Router Interface as JSON	GitHub
uTrade V2 Router Interface as Typescript	GitHub
Import statement codeblock (when available)

uTrade V2 Router Contract Addresses

Network	Address
IoTeX Main Net	0xBd562d5cF2c62Da3143D862aF39eDb6dF59A4679 (Link)

Read-Only Functions

factory

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 IoTeX is 0x839547067bc885db205F5fA42dcFeEcDFf5A8530.

WETH

function WETH() external pure returns (address);

A call to the WETH function returns the address of Wrapped IoTeX (WIOTX) on IoTeX. As this address does not change, it will always return 0xa00744882684c3e4747faefd68d283ea44099d03.

quote

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.

getAmountOut

function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut, uint fee) external pure returns (uint amountOut);

A call to the getAmountOutfunction 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.

getAmountIn

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.

getAmountsOut

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.

getAmountsIn

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.

State-Changing Functions - Liquidity

addLiquidity

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 / 20000 IOTX, a user's liquidity will be added at the ratio of 0.15 USDT to 1 IOTX, 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.

Function Parameters Breakdown

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. If the value of tokenA rapidly increases in comparison to tokenB, the user will require less of tokenA to be added to the pool to maintain the original value of the submitted liquidity. A user could potentially be adding liquidity during an outlier spike in value. If the amount of tokenA required falls below this value, the transaction will revert. This value must be less than or equal to amountADesired.
amountBMin	uint	Sets the minimum amount of tokenB that can added to the pool before the transaction reverts. This acts as a safeguard. If the value of tokenB rapidly increases in comparison to tokenA, the user will require less of tokenB to be added to the pool to maintain the original value of the submitted liquidity. A user could potentially be adding liquidity during an outlier spike in value. If the amount of tokenB required falls below this value, the transaction will revert. This value must be less than or equal to amountBDesired.
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.

Function Return Parameter Breakdown

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.

addLiquidityETH

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 IoTeX, this native asset would be IOTX. This function will convert IOTX to WIOTX, will pair that WIOTX 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 WIOTX 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 IOTX to be added.

  • The msg.value acts as the amountETHDesired. As in, if the ratio between IOTX and the token being paired with it change, this is the number of IOTX that will be added to the pool.

  • Any leftover IOTX is returned to the msg.sender address.

Function Parameter Breakdown

Parameter	Type	Description
token	address	The address of the supplied token for the liquidity pool. In other words, the asset that IOTX 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 IOTX.
(amountETHDesired) msg.value	uint	Sent as the msg.value, the amount of IOTX to be added to liquidity if the value of IOTX 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. If the value of supplied token rapidly increases in comparison to IOTX, the user will require less of the token to be added to the pool to maintain the original value of the submitted liquidity. A user could potentially be adding liquidity during an outlier spike in value. If the amount of the supplied token required falls below this value, the transaction will revert. This value must be less than or equal to amountTokenDesired.
amountETHMin	uint	Sets the minimum amount of IOTX that can added to the pool before the transaction reverts. This acts as a safeguard. If the value of IOTX increases in comparison to the supplied token, the user will require less IOTX to be added to the pool to maintain the original value of the submitted liquidity. A user could potentially be adding liquidity during an outlier spike in value. If the amount of IOTX required falls below this value, the transaction will revert. This value must be less than or equal to amountETHDesired.
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.

Function Return Parameter Breakdown

Parameter	Type	Description
amountToken	uint	The exact amount of the supplied token sent to the pool.
amountETH	uint	The exact amount of IOTX converted to WIOTX, 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.

removeLiquidity

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 XRC-20 tokens.

• In the event one of the assets is paired with IOTX, IOTX will have been wrapped and paired with WIOTX (Wrapped IoTeX). If the user wishes to withdraw WETH instead of withdrawing as ETH, this function should be used instead of removeLiquidityETH .

Function Parameter Breakdown

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.

Function Return Parameter Breakdown

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.

removeLiquidityETH

function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
) external returns (uint amountToken, uint amountETH);

The removeLiquidityETH function removes IOTX as well as the corresponding paired token in the liquidity pool. In other words, this function is used when the pool consists of WIOTX and an XRC-20 token.

• In the event one of the assets is paired with IOTX, IOTX has been wrapped into WIOTX (Wrapped IoTeX). This function will unwrap the WIOTX as the liquidity removed. If the user wishes to withdraw WIOTX instead of withdrawing as IOTX, the removeLiquidity function should be used.

Function Parameter Breakdown

Parameter	Type	Description
token	address	Token address of the XRC-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 IOTX 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 IOTX 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.

Function Return Parameter Breakdown

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 IOTX sent to the address provided in the to parameter.

removeLiquidityWithPermit

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 XRC-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 IOTX, IOTX will have been wrapped and paired with WIOTX (Wrapped IoTeX). If the user wishes to withdraw WIOTX instead of withdrawing as IOTX, this function should be used instead of removeLiquidityETHWithPermit .

Function Parameter Breakdown

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.

Function Return Parameter Breakdown

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.

removeLiquidityETHWithPermit

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 IOTX as well as the corresponding paired token in the liquidity pool. In other words, this function is used when the pool consists of WIOTX and a XRC-20 token. This function operates similarly to the removeLiquidityETHfunction with the added benefit of not requiring pre-approvals using permit.

• In the event one of the assets is paired with IOTX, IOTX has been wrapped into WIOTX (Wrapped IoTeX). This function will unwrap the WIOTX as the liquidity removed. If the user wishes to withdraw WIOTX instead of withdrawing as IOTX, the removeLiquidityWithPermit function should be used.

Function Parameter Breakdown

Parameter	Type	Description
token	address	Token address of the XRC-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 IOTX 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 IOTX 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.

Function Return Parameter Breakdown

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 IOTX sent to the address provided in the to parameter.

removeLiquidityETHSupportingFeeOnTransferTokens

function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
) external returns (uint amountETH);

The removeLiquidityETHSupportingFeeOnTransferTokensfunction is similar to the removeLiquidityETH function, and contains the same call parameters. This function removes IOTX as well as the corresponding paired token in the liquidity pool. In other words, this function is used when the pool consists of WIOTX and a XRC-20 token.

However, this function allows for fee on transfer tokens, such as PAXG, to be used on uTrade.

Function Parameter Breakdown

Parameter	Type	Description
token	address	Token address of the XRC-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 IOTX 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 IOTX 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.

Function Return Parameter Breakdown

Parameter	Value	Description
amountETH	uint	The exact amount of IOTX 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.

removeLiquidityETHWithPermitSupportingFeeOnTransferTokens

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 removeLiquidityETHWithPermitSupportingFeeOnTransferTokensfunction is similar to the removeLiquidityETHWithPermitfunction. This function removes IOTX as well as the corresponding paired token in the liquidity pool. In other words, this function is used when the pool consists of WIOTX and an XRC-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.

Function Parameter Breakdown

Parameter	Type	Description
token	address	Token address of the XRC-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 IOTX 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 IOTX 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.

Function Return Parameter Breakdown

Parameter	Value	Description
amountETH	uint	The exact amount of IOTX 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.

State-Changing Functions - Swap

swapExactTokensForTokens

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.

Function Parameter Breakdown

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.

Function Return Parameter Breakdown

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.

swapTokensForExactTokens

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.

Function Parameter Breakdown

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.

Function Return Parameter Breakdown

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.

swapExactETHForTokens

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 IOTX for a desired token.

Function Parameter Breakdown

Parameter	Type	Description
(amountIn) msg.value	uint	Sent as the msg.value, the amount of IOTX 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 IOTX to WIOTX, 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.

Function Return Parameter Breakdown

Parameter	Type	Description
amounts	uint[] memory	The exact amount of IOTX sent into the swap, as well as the exact return amount of all subsequent swaps.

swapTokensForExactETH

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 IOTX.

Function Parameter Breakdown

Parameter	Type	Description
amountOut	uint	The exact amount of the IOTX 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.

Function Return Parameter Breakdown

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.

swapExactTokensForETH

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 IOTX.

Function Parameter Breakdown

Parameter	Type	Description
amountIn	uint	The amount of tokens being sent to swap into IOTX.
amountOutMin	uint	Sets the minimum amount of the IOTX 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.

Function Parameter Return Breakdown

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.

swapETHForExactTokens

function swapETHForExactTokens(
        uint amountOut, 
        address[] calldata path, 
        address to, 
        uint deadline)
        external
        payable
        returns (uint[] memory amounts);

The swapETHForExactTokens function swaps an exact amount of IOTX for an amount of the desired token.

Function Parameter Breakdown

Parameter	Type	Description
(amountIn) msg.value	uint	Sent as the msg.value, the amount of IOTX 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 IOTX to WIOTX, the first address must be WIOTX.
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.

Function Return Parameter Breakdown

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.

swapExactTokensForTokensSupportingFeeOnTransferTokens

function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
) external;

The swapExactTokensForTokensSupportingFeeOnTransferTokens function is similar to swapExactTokensForTokens as it swaps one XRC-20 token for another XRC-20 token. In addition, this function allows for fee on transfer tokens, such as PAXG, to be used on uTrade.

Function Parameter Breakdown

Name	Type
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.

swapExactETHForTokensSupportingFeeOnTransferTokens

function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
 ) external payable;

The swapExactETHForTokensSupportingFeeOnTransferTokensfunction is similar to swapExactETHForTokens function as it swaps an exact amount of IOTX for XRC-20 tokens. In addition, this function allows for fee on transfer tokens, such as PAXG, to be used on uTrade.

Function Parameter Breakdown

Parameter	Type	Description
(amountIn) msg.value	uint	Sent as the msg.value, the exact amount of IOTX 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 IOTX to WIOTX, the first address must be WIOTX.
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.

swapExactTokensForETHSupportingFeeOnTransferTokens

function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
) external;

The function swapExactTokensForETHSupportingFeeOnTransferTokensis similar to the swapExactTokensForETHfunction, as it swaps an exact amount of XRC-20 tokens for IOTX. In addition, this function allows for fee on transfer tokens, such as PAXG, to be used on uTrade.

Function Parameter Breakdown

Parameter	Type	Description
amountIn	uint	The amount of tokens being sent to swap into IOTX.
amountOutMin	uint	Sets the minimum amount of the IOTX 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.

Interface Code

interface IUnifiRouter01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    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);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    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);
    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);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut, uint fee) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut, uint fee) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}

interface IUnifiRouter02 is IUnifiRouter01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    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);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}