Function create_async_work 

pub unsafe fn create_async_work(
    env: Env,
    async_resource: Value,
    async_resource_name: Value,
    execute: AsyncExecuteCallback,
    complete: AsyncCompleteCallback,
    data: *mut c_void,
    result: *mut AsyncWork,
) -> Result<(), Status>

Available on crate feature napi-1 only.

napi_create_async_work