Multicall

Batch multiple contract read calls into one RPC with multicall

Multicall executes multiple contract read calls in a single RPC round-trip using the Multicall3 contract (or deployless execution). Each call is ABI-encoded and decoded; results are returned in order with success/failure per call.

Import

import (
  "github.com/ethereum/go-ethereum/common"
  "github.com/ChefBingbong/viem-go/abi"
  "github.com/ChefBingbong/viem-go/actions/public"
)

Usage

parsedABI, _ := abi.Parse(erc20ABI)

results, err := public.Multicall(ctx, publicClient, public.MulticallParameters{
  Contracts: []public.MulticallContract{
      {
          Address:      common.HexToAddress("0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48"),
          ABI:          parsedABI,
          FunctionName: "balanceOf",
          Args:         []any{ownerAddr},
      },
      {
          Address:      common.HexToAddress("0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48"),
          ABI:          parsedABI,
          FunctionName: "totalSupply",
      },
  },
  AllowFailure: func() *bool { b := true; return &b }(),
})
if err != nil {
  log.Fatal(err)
}
for i, r := range results {
  if r.Status == "success" {
      fmt.Println(i, r.Result)
  } else {
      fmt.Println(i, r.Error)
  }
}

Parameters

Contracts (required)

Type: []MulticallContract
MulticallContract fields: Address (common.Address), ABI (*abi.ABI), FunctionName (string), Args ([]any). Each element is one contract call.

AllowFailure (optional)

Type: *bool
Default: true
If true, failed calls are included in results with status "failure" and an error; the whole multicall does not fail. If false, the first failure aborts the multicall.

BatchSize (optional)

Type: int
Default: 1024
Maximum calldata size per batch (bytes). Calls are chunked into batches accordingly.

MulticallAddress (optional)

Type: *common.Address
Default: chain default Multicall3 address
Override the multicall contract address.

BlockNumber / BlockTag (optional)

Type: *uint64 or BlockTag
Default: latest
Block at which to execute the calls.

Deployless (optional)

Type: bool
Default: false
If true, use deployless multicall (bytecode execution) for chains without a deployed Multicall3 contract.

MaxConcurrentChunks (optional)

Type: int
Default: 4
Limit concurrent batch executions. Set to 0 or negative for unlimited.

Return type

Multicall returns ([]MulticallResult, error). MulticallResult has Status ("success" or "failure"), Result (any), and Error (error).