Implement useScaffoldMultiReadContract Hook #575
Description
Why We Need This
Contract reads typically require one RPC call per operation. When you need to fetch multiple data points or arrays of objects for example when displaying a dashboard, creating individual hooks for each call becomes inefficient and cumbersome. This multiRead hook lets you make type-safe calls to multiple contracts with different entry points and calldata, then automatically parse results based on your calls - all leveraging the ABIs in deployedContracts.
What to Build
- Create a hook that safely reads from multiple contracts simultaneously using the Multicall contract below
- Follow the same patterns as
useScaffoldMultiWrite()for consistency - Ensure full type safety with autocompletion (note: the contract returns only an array of felts, so parsing must happen within the hook, similar to starknet-react's single hook approach)
- The hook should match the type safety and autocomplete experience of the existing
useScaffoldReadContract - Test implementation using the bulletproof contracts [here](https://github.com/Scaffold-Stark/scaffold-stark-2/tree/v3-bulletproof-contracts)
- make this hold
result of useScaffoldMultiReadContract(calls: [call1, call2]) == [ result of useScaffoldReadContract(call1), result of useScaffoldReadContract(call2) ]
Sample Multicall Contract [feel free to change the source code like function name the return type from Array to Vec or Span, i.e.]
use starknet::ContractAddress;
#[starknet::interface]
pub trait IMulticall<T> {
fn call_contracts(self: @T, contracts: Span<ContractAddress>, entry_point_selectors: Span<felt252>, calldata: Span<Span<felt252>>) -> Array<Span<felt252>>;
}
#[starknet::contract]
pub mod Multicall {
use starknet::ContractAddress;
use super::IMulticall;
use core::array::ArrayTrait;
use starknet::syscalls::call_contract_syscall;
#[storage]
struct Storage {
}
#[constructor]
fn constructor(ref self: ContractState) {}
#[abi(embed_v0)]
impl MulticallImpl of IMulticall<ContractState> {
fn call_contracts(self: @ContractState, contracts: Span<ContractAddress>, entry_point_selectors: Span<felt252>, calldata: Span<Span<felt252>>) -> Array<Span<felt252>> {
let mut results: Array<Span<felt252>> = ArrayTrait::new();
for i in 0..contracts.len() {
let contract = *contracts[i];
let entry_point_selector = *entry_point_selectors[i];
let calldata = *calldata[i];
let result = call_contract_syscall(contract, entry_point_selector, calldata);
results.append(result.unwrap());
}
results
}
}
}