examples: Encoding data when executing an eth_call

[usebeforefree]

I can't seem to find a way to encode the data field of an eth_call.

My goal is to call a function (exampleFunction(address, uint24)) of a deployed contract.

    const contract = try self.client.sendEthCall(
        .{ .london = .{
            .to = contractAddress,
            .data = "a way to format this field",
        } },
        .{
            .block_number = null,
            .tag = .latest,
        },
    );
    defer contract.deinit();

Could you guide me on how to do this, afterwards I will be more than happy to create an example for the given functionality.

Thanks in advance!

[Raiden1411]

You can use the encoder module for this. You need the abi of that function and then use it for the encoder.

You can check the encoder.test.zig file to see how you can achieve this further but here is a simple example

const abi = @import("zabi-abi").abitypes;

const func: abi.Function = .{
    .type = .function,
    .inputs = &.{
        .{ .type = .{ .bool = {} }, .name = "foo" },
        .{ .type = .{ .string = {} }, .name = "bar" },
    },
    .name = "Foo",
    .stateMutability = .nonpayable,
    .outputs = &.{},
};

const fizz: []const u8 = "fizzbuzz";
const encoded = try func.encode(testing.allocator, .{ true, fizz });
defer testing.allocator.free(encoded);

const hex = try std.fmt.allocPrint(testing.allocator, "{s}", .{std.fmt.fmtSliceHexLower(encoded)});
defer testing.allocator.free(hex);

try testing.expectEqualStrings("65c9c0c100000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000866697a7a62757a7a000000000000000000000000000000000000000000000000", hex);