Calling Contract Function via Relayer

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:computer: Environment
I'm making a WEBGL Game Using Unity3D

:memo:Details
Hello everyone!
I am very new to openzeppelin so please bear with me if i you find my question silly.

I have created a Relayer on BSC testnet. Now i want to call a specfic function of my smart contract with "Send Transaction" of relayer. I have deployed my smart Contract on BSC test and also i have ABI code.

The function of my contract which i want to call, require two arguments (See that function below). How to pass all information and call function with Simple JavaScript HTTP(if possible). Or suggest me a best way to do it.

function declareWinner(string memory roomId, address winner)
        external
    {
        Room storage room = rooms[roomId];
        payable(winner).transfer(winnings);

    }
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Is Anyone here to help?

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Hi @thehk12 -

I think the easiest way would be to use ethers.js. You'll want to use DefenderRelayProvider and DefenderRelaySigner as in the example here: https://docs.openzeppelin.com/defender/relay#using-ethers.js

Instead of ERC20_ADDRESS, use the address of that contract and instead of ERC20_ABI use your ABI and then instead of calling erc20.transfer, you'd want to call something like someContract.declareWinner(roomId, winner) (assuming someContract is the variable that your contract is assigned to - this is erc20 in the example). And you'd need to pass the desired arguments in for roomId and winner.

Please let us know if you have any other questions!

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Hello ...

Following up on this. Do you have a solution for Python? Your code example for the txs endpoint does not show any way to specify the function name or its parameters. For example, using web3.py, I would want to do something like:

contract = w3.eth.contract( address=0xXXXXX, abi=myabi.json.file)
contract.functions.methodname(param1, param2).build_transaction(...)

Please advise.

Thank you.

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FYI ... I ended up writing a Node server that uses ethers to do this (very small number of lines of code!). And then I call that from my Python server. Works great in the absence of a Python DefenderRelayer provider.