stellar-registry

Stellar cross-contract calls simplified.

Say you've got:

1. a contract deployed on Stellar's testnet or mainnet
2. a registered name for this contract in Stellar Registry (example: the unverified registry on testnet, which is registered in the official (verified) registry with the name unverified)
3. a Wasm hash that is also in Stellar Registry (example: the registry Wasm used by the unverified contract above)

For now, the stellar_registry crate exports one macro: import_contract_client!

This macro takes the name of the Wasm binary from Stellar Registry:

use soroban_sdk; // needs to be in-scope

stellar_registry::import_contract_client!(registry);

This creates a registry module, equivalent to running:

stellar registry download registry --out-file target/stellar/registry.wasm

...and then importing the Wasm with soroban_sdk like:

mod registry {
    use super::soroban_sdk;
    soroban_sdk::contractimport!(file = "target/stellar/registry.wasm");
}

Within a method, you can now instantiate the client as usual, using the contract ID of the desired contract (such as the unverified contract above):

pub fn __constructor(env: &Env, admin: Address) {
    let registry_client = registry::Client::new(
        env,
        &Address::from_str(
            env,
            "CAMLHKQHNZO2IOIBFUF5BGZ2V62BMS5QCWFFGRCB4NOB3G5OMDA7SGZN",
        ),
    );
    let  = registry_client.fetch_contract_id(&String::from_str(env, &"world"));
}

If you don't want your macro making network calls

First, you should know that this macro doesn't make a network call first. It starts by looking in the current Cargo project's target directory for a .wasm file with the given name. Only if it fails to find one will it run stellar registry download to download the Wasm before importing it.

If you want to avoid network calls in your build-time macro logic, you can set environment variable STELLAR_NO_REGISTRY to 1.

Future

Eventually, this crate will also export an import_contract! macro which will allow importing the contract by name, rather than only the Wasm by name. This will simplify the client creation logic shown above.

Follow progress at https://github.com/theahaco/scaffold-stellar/issues/419