subxt 0.50.0

Interact with Substrate based chains on the Polkadot Network
Documentation 
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//! Construct and submit a transaction.
use subxt::{Error, OnlineClient, PolkadotConfig};
use subxt_signer::sr25519::dev;

// Generate an interface that we can use from the node's metadata.
#[subxt::subxt(runtime_metadata_path = "../artifacts/polkadot_metadata_small.scale")]
mod polkadot {}

#[tokio::main]
async fn main() -> Result<(), Error> {
    // Create a new API client, configured to talk to Polkadot nodes.
    let api = OnlineClient::<PolkadotConfig>::new().await?;

    // Almost all actions are performed at an explicit block. Here we use
    // the current block at the time of running this.
    let at_block = api.at_current_block().await?;

    // Build a balance transfer extrinsic.
    let dest = dev::bob().public_key().into();
    let balance_transfer_tx = polkadot::transactions()
        .balances()
        .transfer_allow_death(dest, 10_000);

    // Submit the balance transfer extrinsic from Alice, and wait for it to be successful
    // and in a finalized block. We get back the extrinsic events if all is well.
    let from = dev::alice();
    let events = at_block
        .transactions()
        .sign_and_submit_then_watch_default(&balance_transfer_tx, &from)
        .await?
        .wait_for_finalized_success()
        .await?;

    // Find a Transfer event and print it.
    if let Some(event) = events.find_first::<polkadot::balances::events::Transfer>() {
        println!("Balance transfer success: {event:?}");
    }

    Ok(())
}