[Feature] Simple API to resolve json-abi item types

[DaniPopes]

Component

dyn-abi, json-abi

Describe the feature you would like

Example: in ethabi you can just call Function::encode_input to ABI-encode data with the function's selector and inputs. cc @prestwich

Additional context

No response

[davebryson]

I'm experimenting with this now to get a better understanding of alloy's APIs. What's the intended replacement forethabi Token in this context ... SolType? Thanks!

[prestwich]

DynSolType is roughly equivalent to ParamKind

The way i would to this is extending the Resolve trait in dyn-abi to have a method that both resolves + encodes

[davebryson]

Here's one approach as a method on Function

pub fn encode_input(&self, args: DynSolValue) -> Result<Vec<u8>> {
   let input_types = self
            .inputs
            .iter()
            .map(|i| i.resolve().expect("valid type"))
            .collect::<Vec<DynSolType>>();
   
    if !input_types.matches(&args) {
            Err(...)
    }
      
    let encoded_args = args.encode_params();
    // prepend selector... etc...
}

I'm actually working on a pull request for this. However, this approach requires json_abi to depend on dyn_abi which already depends on json_abi.... which depends on ... resulting in a cyclic deps problem. Any thoughts on how to get around this?

[prestwich]

yeah, the circular dep is why we need to put this logic in the Resolve trait in dyn-abi. json-abi is strictly a dat format, and should not rely on the type system representation in dyn-abi

[davebryson]

@prestwich Ok, I think I understand what you're after now. A trait is needed in order to implement this logic for Function in dyn-abi but it would really only be implemented once (for Function). Is this what you envision?

[davebryson]

@DaniPopes Following on to this, is there interest in taking a similar approach to provide support for something like event.parse_log() to parse the log into DynSolValues?

[prestwich]

@DaniPopes should we come up with a struct that represents Events?

struct DynEventType {
    topics: [Option<DynSolType>; 4],
    body: DynSolType
}

struct DynEvent {
    topics: [Option<DynSolValue>; 4],
    body: DynSolValue
}

[davebryson]

@DaniPopes @prestwich I'm happy to work on this once you decide on the direction. I've already roughed out an initial solution