feat: Add private channel address to account info rpc (#5489)

* feature: Added channel address to cf-account-info

* refactor: derive address from channel id

* refactor: renamed channel_address to deposit_address

* chore: renamed deposit_address -> btc_vault_deposit_address

* chore: moved btc address derivation to own function

* chore: improved comment

* chore: refactored cf_broker_info

state-chain/custom-rpc/src/lib.rs

@@ -259,6 +259,7 @@ pub enum RpcAccountInfo {
 	Broker {
 		flip_balance: NumberOrHex,
 		earned_fees: any::AssetMap<NumberOrHex>,
+		btc_vault_deposit_address: Option<String>,
 	},
 	LiquidityProvider {
 		balances: any::AssetMap<NumberOrHex>,
@@ -289,9 +290,10 @@ impl RpcAccountInfo {
 		Self::Unregistered { flip_balance: balance.into() }
 	}
 
-	fn broker(balance: u128, broker_info: BrokerInfo) -> Self {
+	fn broker(broker_info: BrokerInfo, balance: u128) -> Self {
 		Self::Broker {
 			flip_balance: balance.into(),
+			btc_vault_deposit_address: broker_info.btc_vault_deposit_address,
 			earned_fees: cf_chains::assets::any::AssetMap::from_iter_or_default(
 				broker_info
 					.earned_fees
@@ -1388,7 +1390,7 @@ where
 					AccountRole::Broker => {
 						let info = api.cf_broker_info(hash, account_id)?;
 
-						RpcAccountInfo::broker(balance, info)
+						RpcAccountInfo::broker(info, balance)
 					},
 					AccountRole::LiquidityProvider => {
 						let info = api.cf_liquidity_provider_info(hash, account_id)?;
@@ -2145,7 +2147,7 @@ mod test {
 	use std::collections::BTreeSet;
 
 	use super::*;
-	use cf_chains::assets::sol;
+	use cf_chains::{assets::sol, btc::ScriptPubkey};
 	use cf_primitives::{
 		chains::assets::{any, arb, btc, dot, eth},
 		FLIPPERINOS_PER_FLIP,
@@ -2170,8 +2172,8 @@ mod test {
 
 	#[test]
 	fn test_broker_serialization() {
-		insta::assert_snapshot!(serde_json::to_value(RpcAccountInfo::broker(
-			0,
+		use cf_chains::btc::BitcoinNetwork;
+		let broker = RpcAccountInfo::broker(
 			BrokerInfo {
 				earned_fees: vec![
 					(Asset::Eth, 0),
@@ -2184,10 +2186,15 @@ mod test {
 					(Asset::ArbUsdc, 0),
 					(Asset::Sol, 0),
 					(Asset::SolUsdc, 0),
-				]
-			}
-		))
-		.unwrap());
+				],
+				btc_vault_deposit_address: Some(
+					ScriptPubkey::Taproot([1u8; 32]).to_address(&BitcoinNetwork::Testnet),
+				),
+			},
+			0,
+		);
+
+		insta::assert_snapshot!(serde_json::to_value(broker).unwrap());
 	}
 
 	#[test]

state-chain/custom-rpc/src/snapshots/custom_rpc__test__broker_serialization.snap

@@ -1,5 +1,6 @@
 ---
 source: state-chain/custom-rpc/src/lib.rs
-expression: "serde_json::to_value(RpcAccountInfo::broker(0,\n            BrokerInfo {\n                earned_fees: vec![(Asset::Eth, 0), (Asset::Btc, 0),\n                    (Asset::Flip, 1000000000000000000), (Asset::Usdc, 0),\n                    (Asset::Usdt, 0), (Asset::Dot, 0), (Asset::ArbEth, 0),\n                    (Asset::ArbUsdc, 0), (Asset::Sol, 0), (Asset::SolUsdc, 0),],\n            })).unwrap()"
+expression: "serde_json::to_value(broker).unwrap()"
+snapshot_kind: text
 ---
-{"earned_fees":{"Arbitrum":{"ETH":"0x0","USDC":"0x0"},"Bitcoin":{"BTC":"0x0"},"Ethereum":{"ETH":"0x0","FLIP":"0xde0b6b3a7640000","USDC":"0x0","USDT":"0x0"},"Polkadot":{"DOT":"0x0"},"Solana":{"SOL":"0x0","USDC":"0x0"}},"flip_balance":"0x0","role":"broker"}
+{"btc_vault_deposit_address":"tb1pqyqszqgpqyqszqgpqyqszqgpqyqszqgpqyqszqgpqyqszqgpqyqsn60vlk","earned_fees":{"Arbitrum":{"ETH":"0x0","USDC":"0x0"},"Bitcoin":{"BTC":"0x0"},"Ethereum":{"ETH":"0x0","FLIP":"0xde0b6b3a7640000","USDC":"0x0","USDT":"0x0"},"Polkadot":{"DOT":"0x0"},"Solana":{"SOL":"0x0","USDC":"0x0"}},"flip_balance":"0x0","role":"broker"}

state-chain/runtime/src/chainflip/address_derivation/btc.rs

@@ -1,5 +1,5 @@
 use super::AddressDerivation;
-use crate::BitcoinThresholdSigner;
+use crate::{BitcoinThresholdSigner, Environment, EpochKey, String};
 use cf_chains::{
 	address::{AddressDerivationApi, AddressDerivationError},
 	btc::deposit_address::DepositAddress,
@@ -44,6 +44,22 @@ impl AddressDerivationApi<Bitcoin> for AddressDerivation {
 	}
 }
 
+/// ONLY FOR USE IN RPC CALLS.
+///
+/// Derives the BTC vault deposit address from the private channel id.
+/// Note: This function will **panic** if the private channel id is out of bounds or if there is
+/// no active epoch key for Bitcoin.
+pub(crate) fn derive_btc_vault_deposit_address(private_channel_id: u64) -> String {
+	let EpochKey { key, .. } = BitcoinThresholdSigner::active_epoch_key()
+		.expect("We should always have a key for the current epoch.");
+	DepositAddress::new(
+		key.current,
+		private_channel_id.try_into().expect("Private channel id out of bounds."),
+	)
+	.script_pubkey()
+	.to_address(&Environment::network_environment().into())
+}
+
 #[test]
 fn test_address_generation() {
 	use crate::Runtime;

state-chain/runtime/src/lib.rs

@@ -11,6 +11,7 @@ pub mod test_runner;
 mod weights;
 use crate::{
 	chainflip::{
+		address_derivation::btc::derive_btc_vault_deposit_address,
 		calculate_account_apy,
 		solana_elections::{
 			SolanaChainTrackingProvider, SolanaEgressWitnessingTrigger, SolanaIngress,
@@ -79,7 +80,7 @@ use pallet_cf_pools::{
 	AskBidMap, AssetPair, HistoricalEarnedFees, OrderId, PoolLiquidity, PoolOrderbook, PoolPriceV1,
 	PoolPriceV2, UnidirectionalPoolDepth,
 };
-use pallet_cf_swapping::{BatchExecutionError, FeeType, Swap};
+use pallet_cf_swapping::{BatchExecutionError, BrokerPrivateBtcChannels, FeeType, Swap};
 use runtime_apis::ChainAccounts;
 
 use crate::{chainflip::EvmLimit, runtime_apis::TransactionScreeningEvent};
@@ -1905,11 +1906,13 @@ impl_runtime_apis! {
 		fn cf_broker_info(
 			account_id: AccountId,
 		) -> BrokerInfo {
-			let earned_fees = Asset::all().map(|asset|
-				(asset, AssetBalances::get_balance(&account_id, asset))
-			).collect();
-
-			BrokerInfo { earned_fees }
+			BrokerInfo {
+				earned_fees: Asset::all().map(|asset|
+					(asset, AssetBalances::get_balance(&account_id, asset))
+				).collect(),
+				btc_vault_deposit_address: BrokerPrivateBtcChannels::<Runtime>::get(&account_id)
+					.map(derive_btc_vault_deposit_address),
+			}
 		}
 
 		fn cf_account_role(account_id: AccountId) -> Option<AccountRole> {
@@ -2177,8 +2180,6 @@ impl_runtime_apis! {
 			// Encode swap
 			match ForeignChain::from(source_asset) {
 				ForeignChain::Bitcoin => {
-					use cf_chains::btc::deposit_address::DepositAddress;
-
 					let private_channel_id =
 						pallet_cf_swapping::BrokerPrivateBtcChannels::<Runtime>::get(&broker_id)
 							.ok_or(
@@ -2221,25 +2222,9 @@ impl_runtime_apis! {
 							},
 						};
 
-					let EpochKey { key, .. } = BitcoinThresholdSigner::active_epoch_key()
-						.expect("We should always have a key for the current epoch.");
-					let deposit_address = DepositAddress::new(
-						key.current,
-						private_channel_id.try_into().map_err(
-							// TODO: Ensure this can't happen.
-							|_| {
-								DispatchErrorWithMessage::Other(
-									"Private channel id out of bounds.".into(),
-								)
-							},
-						)?,
-					)
-					.script_pubkey()
-					.to_address(&Environment::network_environment().into());
-
 					Ok(VaultSwapDetails::Bitcoin {
 						nulldata_payload: encode_swap_params_in_nulldata_payload(params),
-						deposit_address,
+						deposit_address: derive_btc_vault_deposit_address(private_channel_id),
 					})
 				},
 				_ => Err(pallet_cf_swapping::Error::<Runtime>::UnsupportedSourceAsset.into()),

state-chain/runtime/src/runtime_apis.rs

@@ -161,6 +161,7 @@ pub struct LiquidityProviderInfo {
 #[derive(Encode, Decode, Eq, PartialEq, TypeInfo)]
 pub struct BrokerInfo {
 	pub earned_fees: Vec<(Asset, AssetAmount)>,
+	pub btc_vault_deposit_address: Option<String>,
 }
 
 /// Struct that represents the estimated output of a Swap.