Multimint

multimint is a library for managing Fedimint Clients across multiple federations.

The main struct is MultiMint which holds a map of ClientHandleArcs keyed by FederationId, and provides methods for managing and interacting with the clients.

Multimint uses 1 top level directory for all its data, and creates subdirectories for each client. Each client's directory behaves like a standalone Fedimint client.

Example file tree with 2 clients

├── fm_data_dir
│   ├── 15db8cb4f1ec8e484d73b889372bec94812580f929e8148b7437d359af422cd3.db
│   ├── 412d2a9338ebeee5957382eb06eac07fa5235087b5a7d5d0a6e18c635394e9ed.db
│   ├── multimint.db

When you create a new MultiMint instance you pass it a path to the top level directory for all its data. If the directory does not exist it will be created. If the directory already has data from a previous run, it will be loaded.

Example:

use multimint::MultiMint;
use std::path::PathBuf;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
   let work_dir = PathBuf::from("/path/to/fm_data_dir");

   // `new` handles creating a new multimint with no clients or will load the existing databases in the work_dir into ClientHandleArcs
   let multimint = MultiMint::new(work_dir).await?;

   // List the ids of the federations the multimint has clients for
   // E.g. if the work_dir has 2 clients, the ids will be [FederationId, FederationId]
   // If there are no clients, the ids will be an empty vector
   let federation_ids = multimint.ids().await;
   println!("Federation IDs: {:?}", federation_ids);

   // Create a new client by connecting to a federation with an invite code
   let invite_code = "fed1_invite_code";
   // The client's keypair is created based off a 64 byte random secret that is either generated or provided by the user
   let secret = env::var("FM_SECRET").ok_or(None);
    multimint.register_new(invite_code, secret).await?;
   
   // Get a client by its federation id
   let client = multimint.get(&federation_ids[0]).await?;
   println!("Client: {:?}", client);
   
   Ok(())
}

The MultiMint struct provides methods for adding, removing, and updating clients, as well as getting information about the clients and their balances.