How to encode tuple as input parameter to function using web3j

Question

I am attempting to call a solidity function that looks something like the following:

function fillOrder(
    Order memory order,
    uint256 takerAssetFillAmount,
    bytes memory signature
)

Using web3j I would create the function similar to below, however I'm not quite sure how to represent the order which is represented as a struct in Solidity.

List<Type> inputParams = Arrays.asList(???, new 
Uint256(takerAssetFillAmount), new Bytes32(signture));
new Function("fillOrder", inputParams, Collections.emptyList());

Any pointers on how I should represent the struct?

Thanks.

Possible duplicate of [How solidity make function signature with tuple(nested abi)?](https://stackoverflow.com/questions/51757569/how-solidity-make-function-signature-with-tuplenested-abi) — Raghav Sood, Oct 05 '18 at 05:32
@RaghavSood no, that one is about how to calculate function selector when parameters has tuple — DiveInto, Oct 20 '18 at 07:54
@dneo, did you find any solution? If yes, can you please update it as an answer. Thank you. — vanillascotch, Jul 02 '19 at 05:56

score 1 · Answer 1 · answered Nov 13 '19 at 05:14

You can wrap parameters with square brackets.

For example, let's say I have a contract:

contract Test {
    struct Foo {
        uint a;
        string b;
        address c;
    }

    function bar (Foo memory foo) public {
        c = foo.c;
    }
}

I can call bar function with web3.js like this:

contract.methods.foo([123, "123", "0xABC...."]).send({ from: '0x...' })

score 0 · Answer 2 · answered Sep 16 '22 at 03:57

here is the contract address https://goerli.etherscan.io/address/0xd5999bf0ce31a1d9d6a6de2bf03feaff1913cee5#writeContract

in the write function , createSwapOrder is asking nested Tuple . here is the solidity code to show the structure of tuple :

struct Side {
    address user;
    bytes signedRequiredOutput;
    ERC20Component[] erc20s;
    ERC721Component[] erc721s;
    ERC1155Component[] erc1155s;
}

struct ERC20Component {
    uint256 amount;
    address underlying;

    // A signed approval transaction giving `amount` transfer rights
    // of token `underlying` to address(this).
    // bytes signedApproval;
}

struct ERC721Component {
    uint256 tokenId;
    address collection;

    // A signed approval transaction giving `tokenId` tranfer rights
    // of token `collection` to address(this).
    // bytes signedApproval;
}

struct ERC1155Component {
    uint256 tokenId;
    uint256 amount;
    address collection;

    // A signed approval transaction giving `tokenId` tranfer rights
    // of token `collection` to address(this).
    // bytes signedApproval;
}

struct Order {
    Side side0;
    Side side1;
    uint256 expiry;
    bytes32 hashlock;
    bytes32 preimage;
    bool completed;
}

event OrderCreated(address indexed user, bytes32 orderId);

uint256 public totalOrders;
mapping(bytes32 => Order) public orders;

function createSwapOrder(
    Side calldata side0,
    bytes32 hashlock,
    uint256 timelock
) public {

... }

and in first args side0 is asking a nested tuple and this tuple formet should be like this ["0x5B38Da6a701c568545dCfcB03FcB875f56beddC4","0x00",[["32","0x5B38Da6a701c568545dCfcB03FcB875f56beddC4"]],[["32","0x5B38Da6a701c568545dCfcB03FcB875f56beddC4"]],[["32","32","0x5B38Da6a701c568545dCfcB03FcB875f56beddC4"]]],

i hope you can understand the structure how its provided !! and sure it working

score 0 · Answer 3 · answered Oct 04 '22 at 13:46

Web3j offers such classes as StaticStruct and DynamicStruct where you define your struct object via primitives. Here is the sample from my project:

class Value: DynamicStruct {

    private lateinit var offer: String
    private lateinit var availableSince: BigInteger
    private lateinit var availabilityEnd: BigInteger
    private var isConsumed: Boolean = false
    private lateinit var lockedUntil: BigInteger

    constructor(
        offer: String,
        availableSince: BigInteger,
        availabilityEnd: BigInteger,
        isConsumed: Boolean,
        lockedUntil: BigInteger
    ) : super(
        Utf8String(offer), Uint256(availableSince),
        Uint256(availabilityEnd), Bool(isConsumed),
        Uint256(lockedUntil)
    ) {
        this.offer = offer
        this.availableSince = availableSince
        this.availabilityEnd = availabilityEnd
        this.isConsumed = isConsumed
        this.lockedUntil = lockedUntil
    }

    constructor(
        offer: Utf8String,
        availableSince: Uint256,
        availabilityEnd: Uint256,
        isConsumed: Bool,
        lockedUntil: Uint256
    ) : super(offer, availableSince, availabilityEnd, isConsumed, lockedUntil) {
        this.offer = offer.value
        this.availableSince = availableSince.value
        this.availabilityEnd = availabilityEnd.value
        this.isConsumed = isConsumed.value
        this.lockedUntil = lockedUntil.value
    }

}

Ideally you just need to pass this struct instance to you contract method as a parameter where contract is autogenerated over $web3j solidity generate -b /path/to/<smart-contract>.bin -a /path/to/<smart-contract>.abi -o /path/to/src/main/java -p com.your.organisation.name command.

However personally I faced with issue to make this console command working and have to implement required logic by my own. This is in the progress now.

How to encode tuple as input parameter to function using web3j

3 Answers3