Controller

The prevention of anti-front-running is implemented by requiring that all method calls to the DEX must be only invoked by the Geode. The user submits a request to the Geode by signing the message without spending gas. The Geode later delegates that request to the DEX for a fee that is deducted from the output token.

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constructor()

constructor(address _relayer,address _router,address _factory);

Initializes the Controller, Uniswap Factory, and Router contracts and assigns a relayer.

relayers

mapping (address => bool) public relayers;

Key-value pair map that keeps track of the trusted relayers.

Parameter	Type
key	address	Input address
value	bool	True: address is a trusted relayer. False : otherwise

uniswapV2TrustedPair

mapping (address => bool) public uniswapV2TrustedPair;

Key-value pair map that keeps track of the trusted Uniswap token pair addresses.

Parameter	Type
key	address	Input address
value	bool	True: address is a trusted pair. False : otherwise

relayerOnly()

modifier relayerOnly();

Verifies msg.sender is a trusted relayer address, otherwise reverts the function call.

setRelayer()

function setRelayer(address _relayer) public onlyOwner()

Assigns the input address as a trusted relayer, can only be invoked by the contract owner.

Parameter	Type
_relayer	address	Input address

isTrustedUniswapV2Pair()

function isTrustedUniswapV2Pair(address pair) external override returns (bool);

Checks the input address to determine whether it is a trusted Uniswap pair address or not, returns bool.

Parameter	Type
pair	address	Input address

addTrustedUniswapV2Pair()

function addTrustedUniswapV2Pair(address pair) public onlyOwner();

Adds the input address as a trusted Uniswap pair address, can only be invoked by the contract owner.

Parameter	Type
pair	address	Input address

removeTrustedUniswapV2Pair()

function removeTrustedUniswapV2Pair(address pair) public onlyOwner();

Removes the pair address from the uniswapV2TrustedPair map, can only be invoked by the contract owner.

Parameter	Type
pair	address	Input address

gTokenTransferFrom()

function gTokenTransferFrom(
    address asset,
    address from,
    address to,
    uint256 amount
) public relayerOnly();

Transfers ERC20 tokens from a sender address to a recipient address, can only be invoked by a relayer.

Parameter	Type
asset	address	The address of the ERC20 token
from	address	Sender address
to	address	Recipient address
amount	uint256	Amount of tokens to be transferred

uniswapV2AddLiquidity()

function uniswapV2AddLiquidity(
    address from,
    address tokenA,
    address tokenB,
    uint256 amountADesired,
    uint256 amountBDesired,
    uint256 amountAMin,
    uint256 amountBMin,
    address to,
    uint256 deadline,
    bool gasIsTokenA
) public relayerOnly();

This method initially checks for either token A or B balance (depending on gasIsTokenA), to make sure that the user could pay for gas. Then, deducts the token amount, which is transferred to the relayer.

Supplies the token pair to the Uniswap liquidity pool, can only be invoked by a relayer and input tokens must be both wrapped tokens. Any leftover tokens that are not added to the liquidity pool will be refunded to the sender.

Parameter	Type
from	address	The sender address
tokenA	address	Wrapped Token A address
tokenB	address	Wrapped Token B address
amountADesired	uint256	The amount of A added to the liquidity pool if the B/A price <= (amountofBDesired / amountofADesired) price
amountBDesired	uint256	The amount of B added to the liquidity pool if the A/B price <= (amountofADesired / amountofBDesired) price
amountAMin	uint256	Bounds the extent to which the B/A price can go up before the transaction reverts. Must be <= amountADesired
amountBMin	uint256	Bounds the extent to which the A/B price can go up before the transaction reverts. Must be <= amountBDesired
to	address	The recipient address of the liquidity token. In this project, it is most likely the sender's address, since they provided liquidity, they should be entitled to getting rewarded with liquidity tokens
deadline	uint256	Unix timestamp after which the transaction is reverted
gasIsTokenA	bool	User to pay gas in Token A or Token B

uniswapV2SwapExactTokensForTokens()

function uniswapV2SwapExactTokensForTokens(
    address from,
    uint256 amountIn,
    uint256 amountOutMin,
    address[] calldata path,
    address to,
    uint256 deadline
) public relayerOnly();

This method initially checks for the balance of the input token, to make sure that the user could pay for gas. Then after the swapping of tokens, deducts the output token amount, which is transferred to the relayer.

Swaps an exact amount of input tokens for as much of output tokens as possible, can only be invoked by a relayer. Any leftover tokens that are not swapped will be refunded to the sender.

Parameter	Type
from	address	The sender address
amountIn	uint256	The amount of input tokens to be sent
amountOutMin	uint256	The minimum amount of tokens that must be received, otherwise the transaction reverts
path	address[]	An array of token addresses. path.length >= 2
to	address	Recipient of the output tokens. In this project, it is also the sender's address
deadline	uint256	Unix timestamp after which the transaction is reverted

uniswapV2SwapTokensForExactTokens()

function uniswapV2SwapTokensForExactTokens(
    address from,
    uint256 amountIn,
    uint256 amountOutMin,
    address[] calldata path,
    address to,
    uint256 deadline
) public relayerOnly();

This method initially checks for the balance of the input token, to make sure that the user could pay for gas. Then after the swapping of tokens, deducts the output token amount, which is transferred to the relayer.

Swaps an amount of input tokens for exact amount of output tokens, can only be invoked by a relayer. Any leftover tokens that are not swapped will be refunded to the sender.

Parameter	Type
from	address	The sender address
amountInMax	uint256	The minimum amount of tokens that must be sent, otherwise the transaction reverts
amountOut	uint256	The amount of output tokens to be sents
path	address[]	An array of token addresses. path.length >= 2
to	address	Recipient of the output tokens. In this project, it is also the sender's address
deadline	uint256	Unix timestamp after which the transaction is reverted