Invalid number of arguments to Solidity function (trying to retrieve mapping)

Question

The solidity contract has defined the following mapping

struct recordStruct {
    uint256 price;
    uint64 time;
}

mapping(address => recordStruct[]) public records;

Question: How can we use Web3.js to retrieve the entire mapping?

If this is not possible, how can we pass in the address and receive the object stored in the recordStruct array?

Attempt When using the following web3 code:

var record = await MyContractInstance.records.call('0xDbB7d1Ed07F8D1D0C5D5bB9b9e427E997f240F7d')

I get the following error

(node:2452) UnhandledPromiseRejectionWarning: Error: Invalid number of arguments to Solidity function

I am using Web3.js 1.0.0-beta.34

Answer 1

You need to specify both the address and the index of the array, since the ABI gonna have this structure:

[
    {
        "constant": true,
        "inputs": [
            {
                "name": "",
                "type": "address"
            },
            {
                "name": "",
                "type": "uint256"
            }
        ],
        "name": "records",
        "outputs": [
            {
                "name": "price",
                "type": "uint256"
            },
            {
                "name": "time",
                "type": "uint64"
            }
        ],
        "payable": false,
        "stateMutability": "view",
        "type": "function"
    }
]

And consider that the javascript code is also not completely correct:

var record = await MyContractInstance.records('0xDbB7d1Ed07F8D1D0C5D5bB9b9e427E997f240F7d', 0).call({ from: ... })

or

var record = await MyContractInstance.methods.records('0xDbB7d1Ed07F8D1D0C5D5bB9b9e427E997f240F7d', 0).call({ from: ... })

should work.