Enum dispatch

In most production contracts you want to handle multiple message types in a single contract. Unfortunately you can't create multiple endpoints of the same type in a single contract, so you need to dispatch based on the message type.

The most common way to do this is to use an enum to represent the different message types and then match on that enum in the endpoint.

💡

If this sounds like something you don't want to do manually, we got you covered! The sylvia crate provides a procedural macro to generate the boilerplate code for you.

You can find the documentation of the sylvia crate here.

contract.rs

#[cw_serde]
enum ExecuteMsg {
    Add { value: i32 },
    Subtract { value: i32 },
}
 
#[cfg_attr(not(feature = "library"), entry_point)]
pub fn execute(
    deps: DepsMut,
    env: Env,
    info: MessageInfo,
    msg: ExecuteMsg,
) -> StdResult<Response> {
    match msg {
        ExecuteMsg::Add { value } => {
            // TODO: Add operation
        }
        ExecuteMsg::Subtract { value } => {
            // TODO: Subtract operation
        }
    }
 
    Ok(Response::new())
}

Library feature Advanced