Release notes

Release notes and unreleased changes can be found in the CHANGELOG

Usage

This crate supports two sets of APIs for users with different needs:

• Macro-driven. Gives you a cross-contract binding in a single macro invocation.
• Generation-based. Gives you more control and is transparent about what code you end up using, but requires more setup.

Macro API

Checkout the delegator-macro example for a standalone smart contract using macro API to make a cross-contract call.

To generate a trait named ContractName with ext interface named ext_name based on ABI located at path/to/abi.json (relative to the current file's directory):

near_abi_ext! { mod ext_name trait ContractName for "path/to/abi.json" }

Now, assuming you have an ext_account_id: near_sdk::AccountId representing the contract account id, you can make a cross-contract call like this:

let promise = ext_adder::ext(ext_account_id).my_method_name(arg1, arg2);

Generation API

Checkout the delegator-generation example for a standalone project using generation API to make a cross-contract call.

First, we need our package to have a build.rs file that runs the generation step. The following snippet will generate the contract trait in abi.rs under path/to/out/dir:

fn main() -> anyhow::Result<()> {
    near_sdk_abi::Generator::new("path/to/out/dir".into())
        .file(near_sdk_abi::AbiFile::new("path/to/abi.json"))
        .generate()?;
    Ok(())
}

The resulting file, however, is not included in your source set by itself. You have to include it manually; the recommended way is to create a mod with a custom path:

#[path = "path/to/out/dir/abi.rs"]
mod mymod;

Now, assuming you have an ext_account_id: near_sdk::AccountId representing the contract account id, you can make a cross-contract call like this:

let promise = ext_adder::ext(ext_account_id).my_method_name(arg1, arg2);

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as below, without any additional terms or conditions.

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.