Make working with nested queries a touch easier (#714)

* First pass adding functions to get blocks and extrinsics

* cargo fmt and cache block events

* prefix block hash with 0x

* pin streams for better ergonomics and add an example of subscribing to blocks

* remove unused var

* standardise on _all, _best and _finalized for different block header subs

* WIP center subscribing around blocks

* Remove the event filtering/subscribing  stuff

* clippy

* we need tokio, silly clippy

* add extrinsic_index() call

* Update subxt/src/blocks/block_types.rs

Co-authored-by: Andrew Jones <ascjones@gmail.com>

* Add dynbamic nested query example and make dynamic::tx a little easier to work with

* calL_value -> inner_tx

* rename example to dynamic_multisig to align with #713 naming

* align dynamic and static multisig examples

* Fix comment typo

Co-authored-by: Niklas Adolfsson <niklasadolfsson1@gmail.com>

Co-authored-by: Andrew Jones <ascjones@gmail.com>
Co-authored-by: Niklas Adolfsson <niklasadolfsson1@gmail.com>

examples/examples/dynamic_multisig.rs

@@ -0,0 +1,79 @@
+// Copyright 2019-2022 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 v0.9.31-3711c6f9b2a.
+//!
+//! E.g.
+//! ```bash
+//! curl "https://github.com/paritytech/polkadot/releases/download/v0.9.31/polkadot" --output /usr/local/bin/polkadot --location
+//! polkadot --dev --tmp
+//! ```
+
+use sp_keyring::AccountKeyring;
+use subxt::{
+    dynamic::Value,
+    tx::PairSigner,
+    OnlineClient,
+    PolkadotConfig,
+};
+
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    tracing_subscriber::fmt::init();
+
+    // My account.
+    let signer_account = AccountKeyring::Alice;
+    let signer_account_id = signer_account.to_account_id();
+    let signer = PairSigner::new(signer_account.pair());
+
+    // Transfer balance to this destination:
+    let dest = AccountKeyring::Bob.to_account_id();
+
+    // Create a client to use:
+    let api = OnlineClient::<PolkadotConfig>::new().await?;
+
+    // Create the inner balance transfer call.
+    let inner_tx = subxt::dynamic::tx(
+        "Balances",
+        "transfer",
+        vec![
+            Value::unnamed_variant("Id", [Value::from_bytes(&dest)]),
+            Value::u128(123_456_789_012_345),
+        ],
+    );
+
+    // Now, build an outer call which this inner call will be a part of.
+    // This sets up the multisig arrangement.
+    //
+    // Note: Since this is a dynamic call, we can either use named or unnamed
+    // arguments (if unnamed, the order matters).
+    let tx = subxt::dynamic::tx(
+        "Multisig",
+        "as_multi",
+        vec![
+            ("threshold", Value::u128(1)),
+            (
+                "other_signatories",
+                Value::unnamed_composite([Value::from_bytes(&signer_account_id)]),
+            ),
+            ("maybe_timepoint", Value::unnamed_variant("None", [])),
+            ("call", inner_tx.into_value()),
+            (
+                "max_weight",
+                Value::named_composite([
+                    ("ref_time", Value::u128(10000000000)),
+                    ("proof_size", Value::u128(1)),
+                ]),
+            ),
+        ],
+    );
+
+    // Submit it:
+    let encoded = hex::encode(&api.tx().call_data(&tx)?);
+    println!("Call data: {encoded}");
+    let tx_hash = api.tx().sign_and_submit_default(&tx, &signer).await?;
+    println!("Submitted tx with hash {tx_hash}");
+
+    Ok(())
+}

examples/examples/multisig.rs

@@ -0,0 +1,76 @@
+// Copyright 2019-2022 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 v0.9.31-3711c6f9b2a.
+//!
+//! E.g.
+//! ```bash
+//! curl "https://github.com/paritytech/polkadot/releases/download/v0.9.31/polkadot" --output /usr/local/bin/polkadot --location
+//! polkadot --dev --tmp
+//! ```
+
+use sp_keyring::AccountKeyring;
+use subxt::{
+    tx::PairSigner,
+    OnlineClient,
+    PolkadotConfig,
+};
+
+#[subxt::subxt(runtime_metadata_path = "../artifacts/polkadot_metadata.scale")]
+pub mod polkadot {}
+
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    tracing_subscriber::fmt::init();
+
+    // My account.
+    let signer_account = AccountKeyring::Alice;
+    let signer_account_id = signer_account.to_account_id();
+    let signer = PairSigner::new(signer_account.pair());
+
+    // Transfer balance to this destination:
+    let dest = AccountKeyring::Bob.to_account_id();
+
+    // Create a client to use:
+    let api = OnlineClient::<PolkadotConfig>::new().await?;
+
+    // Create the inner balance transfer call.
+    //
+    // Note: This call, being manually constructed, will have a specific pallet and call index
+    // which is determined by the generated code. If you're trying to submit this to a node which
+    // has the pallets/calls at different indexes, it will fail. See `dynamic_multisig.rs` for a
+    // workaround in this case which will work regardless of pallet and call indexes.
+    let inner_tx = polkadot::runtime_types::polkadot_runtime::RuntimeCall::Balances(
+        polkadot::runtime_types::pallet_balances::pallet::Call::transfer {
+            dest: dest.into(),
+            value: 123_456_789_012_345,
+        },
+    );
+
+    // Now, build an outer call which this inner call will be a part of.
+    // This sets up the multisig arrangement.
+    let tx = polkadot::tx().multisig().as_multi(
+        // threshold
+        1,
+        // other signatories
+        vec![signer_account_id],
+        // maybe timepoint
+        None,
+        // call
+        inner_tx,
+        // max weight
+        polkadot::runtime_types::sp_weights::weight_v2::Weight {
+            ref_time: 10000000000,
+            proof_size: 1,
+        },
+    );
+
+    // Submit the extrinsic with default params:
+    let encoded = hex::encode(&api.tx().call_data(&tx)?);
+    println!("Call data: {encoded}");
+    let tx_hash = api.tx().sign_and_submit_default(&tx, &signer).await?;
+    println!("Submitted tx with hash {tx_hash}");
+
+    Ok(())
+}