Remove decoding bit from "extrinsics" and reference decoding in "blocks" (#951)

* Remove decoding bits from 'tx' and reference decoding in 'blocks' instead

* newline

* doc and fmt fixes

examples/examples/block_extrinsics.rs

@@ -1,99 +0,0 @@
-// Copyright 2019-2023 Parity Technologies (UK) Ltd.
-// This file is dual-licensed as Apache-2.0 or GPL-3.0.
-// see LICENSE for license details.
-
-//! To run this example, a local polkadot node should be running. Example verified against polkadot v0.9.28-9ffe6e9e3da.
-//!
-//! E.g.
-//! ```bash
-//! curl "https://github.com/paritytech/polkadot/releases/download/v0.9.28/polkadot" --output /usr/local/bin/polkadot --location
-//! polkadot --dev --tmp
-//! ```
-
-use futures::StreamExt;
-use sp_keyring::AccountKeyring;
-use std::time::Duration;
-use subxt::{tx::PairSigner, OnlineClient, PolkadotConfig};
-
-#[subxt::subxt(runtime_metadata_path = "../artifacts/polkadot_metadata.scale")]
-pub mod polkadot {}
-
-/// Subscribe to all events, and then manually look through them and
-/// pluck out the events that we care about.
-#[tokio::main]
-async fn main() -> Result<(), Box<dyn std::error::Error>> {
-    // Create a client to use:
-    let api = OnlineClient::<PolkadotConfig>::new().await?;
-
-    // Subscribe to (in this case, finalized) blocks.
-    let mut block_sub = api.blocks().subscribe_finalized().await?;
-
-    // While this subscription is active, balance transfers are made somewhere:
-    tokio::task::spawn({
-        let api = api.clone();
-        async move {
-            let signer = PairSigner::new(AccountKeyring::Alice.pair());
-            let mut transfer_amount = 1_000_000_000;
-
-            // Make small balance transfers from Alice to Bob in a loop:
-            loop {
-                let transfer_tx = polkadot::tx()
-                    .balances()
-                    .transfer(AccountKeyring::Bob.to_account_id().into(), transfer_amount);
-                api.tx()
-                    .sign_and_submit_default(&transfer_tx, &signer)
-                    .await
-                    .unwrap();
-
-                tokio::time::sleep(Duration::from_secs(10)).await;
-                transfer_amount += 100_000_000;
-            }
-        }
-    });
-
-    // Get each finalized block as it arrives.
-    while let Some(block) = block_sub.next().await {
-        let block = block?;
-
-        let block_hash = block.hash();
-        println!(" Block {:?}", block_hash);
-
-        // Ask for the extrinsics for this block.
-        let extrinsics = block.body().await?.extrinsics();
-
-        let transfer_tx = extrinsics.find_first::<polkadot::balances::calls::types::Transfer>();
-        println!(" Transfer tx: {:?}", transfer_tx);
-
-        // Ask for the extrinsics for this block.
-        for extrinsic in extrinsics.iter() {
-            let extrinsic = extrinsic?;
-
-            println!(
-                "  Extrinsic block index {:?}, pallet index {:?}, variant index {:?}",
-                extrinsic.index(),
-                extrinsic.pallet_index(),
-                extrinsic.variant_index()
-            );
-
-            let root_extrinsic = extrinsic.as_root_extrinsic::<polkadot::Call>();
-            println!("   As root extrinsic {:?}\n", root_extrinsic);
-
-            let pallet_extrinsic = extrinsic
-                .as_pallet_extrinsic::<polkadot::runtime_types::pallet_balances::pallet::Call>();
-            println!(
-                "   Extrinsic as Balances Pallet call: {:?}\n",
-                pallet_extrinsic
-            );
-
-            let call = extrinsic.as_extrinsic::<polkadot::balances::calls::types::Transfer>()?;
-            println!(
-                "   Extrinsic as polkadot::balances::calls::Transfer: {:?}\n\n",
-                call
-            );
-        }
-
-        println!("\n");
-    }
-
-    Ok(())
-}

examples/examples/blocks_subscribing.rs

@@ -31,8 +31,12 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
             let events = ext.events().await?;
             let bytes_hex = format!("0x{}", hex::encode(ext.bytes()));
 
+            // See the API docs for more ways to decode extrinsics:
+            let decoded_ext = ext.as_root_extrinsic::<polkadot::Call>();
+
             println!("    Extrinsic #{idx}:");
             println!("      Bytes: {bytes_hex}");
+            println!("      Decoded: {decoded_ext:?}");
             println!("      Events:");
 
             for evt in events.iter() {