Contract calldata api

[0xdewy]

Hey I wanted to use the library to construct calldata for contract functions, but I wasn't able to find anything.

I just did a quick change to see if I could expose the api for this, but I'm happy to clean it up if it makes sense.

[tomusdrw]

Hey! Thanks for the PR, but I don't feel this suits the interface of web3. This can easily be done using ethabi directly.

I'm willing to accept a PR that simply exposes the ethabi::Contract reference, like so:

/// Get the underlying contract ABI.
pub fn abi(&self) -> &ethabi::Contract {
  &self.abi
}

With this you can get the call data via:

let bytes = contract.abi().function(func)?.encode_input(&params.into_tokens());

Also see #17 & #120

[tomusdrw]

The error is there for a reason, simply unwraping will cause panics in case the function is not found.

[0xdewy]

Thanks for pointing me towards #17 .. ethabi_derive looks really nice 👌
Sorry about the unwrap() .. should have been an issue not a pull request 🙄

[tomusdrw]

No worries @kyledewy, thanks a lot for the contribution!

[tomusdrw]

Awesome, cheers!