Solidity API

TradeToken

This contract is based on OpenZeppelin's ERC20 implementation and includes security features like ownership and reentrancy protection.

_Implements an advanced and customizable ERC20 token with wrapping and unwrapping capabilities, wrap ratios and secure transfer handling.

The contract supports two types of tokens:

• Mintable: New tokens can be created by the owner
• Wrappable: Tokens that can be wrapped into other TradeToken

Security features:

• Reentrancy protection on all state-modifying functions
• Ownership controls for sensitive operations
• Transfer acceptance checks for contract recipients
• Twin contract verification for wrapping operations_

TradeTokenType

Defines the type of TradeToken

enum TradeTokenType {
  Mintable,
  Wrappable
}

tradeTokenType

enum TradeToken.TradeTokenType tradeTokenType

The type of this TradeToken instance

wrapRatios

mapping(address => uint256) wrapRatios

_ Mapping of TradeToken addresses to their wrap ratios_

attachments

mapping(string => address) attachments

Mapping to track IPFS Content Identifiers (CIDs) and their submitters Maps CID strings to the address who submitted them

AttachmentAdded

event AttachmentAdded(string cid, address submitter)

Emitted when a new attachment is added to the contract

Parameters

Name	Type	Description
cid	string	IPFS Content Identifier of the attachment
submitter	address	Address that submitted the attachment

WrapRatioAdded

event WrapRatioAdded(address childTradeTokenAddress, uint256 ratio)

Emitted when a new wrap ratio is added for a child Trade Token

Parameters

Name	Type	Description
childTradeTokenAddress	address	Address of the child Trade Token
ratio	uint256	The wrap ratio scaled by 10^18

WrapRatioReceived

event WrapRatioReceived(address tradeTokenAddress, uint256 ratio)

Emitted when a wrap ratio is received from another Trade Token

Parameters

Name	Type	Description
tradeTokenAddress	address	Address of the Trade Token setting the ratio
ratio	uint256	The received wrap ratio

TradeTokenMintingNotAllowed

error TradeTokenMintingNotAllowed()

TradeTokenUnauthorizedTradeTokenOwner

error TradeTokenUnauthorizedTradeTokenOwner()

TradeTokenInvalidTwinContract

error TradeTokenInvalidTwinContract(address target)

TradeTokenWrapRatioNotRegistered

error TradeTokenWrapRatioNotRegistered(address target)

TradeTokenWrapRatioAlreadyExists

error TradeTokenWrapRatioAlreadyExists(address target)

TradeTokenInsufficientBalanceForWrap

error TradeTokenInsufficientBalanceForWrap(uint256 available, uint256 required)

TradeTokenTransferFailed

error TradeTokenTransferFailed(address to, uint256 value)

TradeTokenAttachmentAlreadyAdded

error TradeTokenAttachmentAlreadyAdded(string cid)

TradeTokenNonZeroInitialSupplyForWrappable

error TradeTokenNonZeroInitialSupplyForWrappable()

InvalidCid

error InvalidCid()

constructor

constructor(address _initialOwner, string _tokenName, string _tokenSymbol, uint256 _initialSupply, enum TradeToken.TradeTokenType _tradeTokenType) public

Sets up the Trade Token with initial parameters

Parameters

Name	Type	Description
_initialOwner	address	Address of the initial owner
_tokenName	string	Name of the token
_tokenSymbol	string	Symbol of the token
_initialSupply	uint256	Initial supply to mint
_tradeTokenType	enum TradeToken.TradeTokenType	Type of the Trade Token (Mintable or Wrappable)

mint

function mint(address _account, uint256 _value) external

Creates new tokens and assigns them to the specified account

Parameters

Name	Type	Description
_account	address	Address to receive the minted tokens
_value	uint256	Amount of tokens to mint Requirements: - Caller must be the contract owner - Token must be of Mintable type

burn

function burn(uint256 _value) external

Burns sender's owned tokens

Parameters

Name	Type	Description
_value	uint256	Amount of tokens to be burnt Requirements: - Caller must own atleast value amount of tokens

wrap

function wrap(uint256 _value, address _wrapperTradeToken, address _to) external

Wraps tokens into another TradeToken at the predefined ratio

Parameters

Name	Type	Description
_value	uint256	Amount of tokens to wrap
_wrapperTradeToken	address	Address of the target TradeToken to wrap into
_to	address	Address to receive the wrapped tokens Requirements: - Wrap ratio must be registered for the target TradeToken - Caller must have sufficient balance - Contract must not be reentrant

unwrap

function unwrap(uint256 _value, address _wrappedTradeToken, address _to) external

Unwraps tokens back to their original form

Parameters

Name	Type	Description
_value	uint256	Amount of wrapped tokens to unwrap
_wrappedTradeToken	address	Address of the TradeToken containing the original tokens
_to	address	Address to receive the unwrapped tokens Requirements: - Caller must be the contract owner - Wrap ratio must be registered - Contract must not be reentrant

onReceiveWrappedTokens

function onReceiveWrappedTokens(uint256 _value, address _to) external

Callback function for receiving wrapped tokens

Parameters

Name	Type	Description
_value	uint256	Amount of tokens to mint
_to	address	Address to receive the minted tokens Requirements: - Caller must be a verified twin contract - The call must not be reentrant

setWrapRatio

function setWrapRatio(address _childTradeTokenAddress, uint256 _ratio) external

Sets the wrap ratio for a child TradeToken

Parameters

Name	Type	Description
_childTradeTokenAddress	address	Address of the child TradeToken
_ratio	uint256	Wrap ratio scaled by 10^18 Requirements: - Child TradeToken must be a verified twin contract - Caller must be the owner of the child TradeToken - Contract must not be reentrant - Wrap ratio must not already be set for the child TradeToken

getWrapRatio

function getWrapRatio(address _tradeTokenAddress) external view returns (uint256)

Returns the wrap ratio for a given TradeToken address

Parameters

Name	Type	Description
_tradeTokenAddress	address	Address of the TradeToken to query

Return Values

Name	Type	Description
[0]	uint256	The wrap ratio scaled by 10^18

onReceiveWrapRatio

function onReceiveWrapRatio(uint256 _ratio) external

Callback function when receiving a wrap ratio from another TradeToken

Parameters

Name	Type	Description
_ratio	uint256	The received wrap ratio Requirements: - Caller must be another TradeToken contract with the same deployed bytecode

transfer

function transfer(address _to, uint256 _value) public virtual returns (bool)

Overrides ERC20 transfer function with additional security checks

Parameters

Name	Type	Description
_to	address	Address to transfer tokens to
_value	uint256	Amount of tokens to transfer

Return Values

Name	Type	Description
[0]	bool	bool indicating success Requirements: - Contract must not be reentrant - Recipient contract must properly implement onReceiveERC20 if it's a contract

transferFrom

function transferFrom(address _from, address _to, uint256 _value) public virtual returns (bool)

Overrides ERC20 transferFrom function with additional security checks

Parameters

Name	Type	Description
_from	address	Address to transfer tokens from
_to	address	Address to transfer tokens to
_value	uint256	Amount of tokens to transfer

Return Values

Name	Type	Description
[0]	bool	bool indicating success Requirements: - Contract must not be reentrant - Recipient contract must properly implement onReceiveERC20 if it's a contract

addAttachment

function addAttachment(string _cid) external

Adds a new IPFS attachment to the contract

Parameters

Name	Type	Description
_cid	string	IPFS Content Identifier for the attachment Requirements: - Caller must be the contract owner - CID must not already be registered

_verifyTwinContractBytecode

function _verifyTwinContractBytecode(address _target) internal view

Verifies that the target contract has identical bytecode

Parameters

Name	Type	Description
_target	address	Address of the contract to verify

_extCodeHash

function _extCodeHash(address _account) private view

Retrieves the code hash of the contract deployed at the specified address.

Parameters

Name	Type	Description
_account	address	Address to query