feat: impl Clone for Config struct

[markphelps]

I want to be able to clone a config object to use for multiple clients, ie:

    let flipt_config = flipt::Config::default();

    flipt::meta::MetaClient::new(flipt_config)?
        .info()
        .get()
        .await?;

    let flipt_client = flipt::api::ApiClient::new(flipt_config)?;

Since the clients take ownership of the config argument, the only (easy) way I can see to do this is to implement Clone for Config and then .clone() it for each client I want to use.

Im not sure if this is the 'best' or idiomatic way to do this though.. so feel free to push back @brettbuddin

[brettbuddin]

I'll give this some 👀 this evening. I think we can do one better but I need to look through the struct's shape first.

[brettbuddin]

With this you'll need to call clone() outside of the constructor unless you borrow the Config in ApiClient::new. I would recommend not borrowing and keep the contract as is.

Since you're copying anyway, it seems best to let the caller own when they want that to happen. This ensures that that the (likely?) common case of having a single config and client will result in no copies, and the more complicated cases like you've describe are possible.

Adjusting your example, you'll have something like this:

let flipt_config = flipt::Config::default();

// Clones flipt_config and moves it into MetaClient::new
let meta_client = flipt::meta::MetaClient::new(flipt_config.clone())?
    .info()
    .get()
    .await?;

// Moves the original into ApiClient::new
let flipt_client = flipt::api::ApiClient::new(flipt_config)?;

In a perfect world you'd be able to implement Copy and make that all automatic, but none of the fields of Config have Copy. Clone it is then.

[GeorgeMac]

What @brettbuddin said.

[markphelps]

So did I do good Crab? 🦀