Macros: Return optional extrinsic instead of unwrapping (#709)

* remove unwraps from macros and add Option return value instead

fix examples

fix examples

* fix macro and add unit tests

* fix tests

compose-macros/src/lib.rs

@@ -25,21 +25,28 @@ pub use log;
 
 mod rpc;
 
-/// Generates the extrinsic's call field for a given module and call passed as &str
+/// Generates the extrinsic's call field for a given module and call passed as &str, if found in the metadata.
+/// Otherwise None is returned.
 /// # Arguments
 ///
 /// * 'node_metadata' - This crate's parsed node metadata as field of the API.
-/// * 'pallet' - Pallet name as &str for which the call is composed.
+/// * 'pallet_name' - Pallet name as &str for which the call is composed.
 /// * 'call_name' - Call name as &str
 /// * 'args' - Optional sequence of arguments of the call. They are not checked against the metadata.
-/// As of now the user needs to check himself that the correct arguments are supplied.
 #[macro_export]
 macro_rules! compose_call {
-($node_metadata: expr, $pallet: expr, $call_name: expr $(, $args: expr) *) => {
+($node_metadata: expr, $pallet_name: expr, $call_name: expr $(, $args: expr) *) => {
         {
-			let pallet_metadata = $node_metadata.pallet_by_name($pallet).unwrap().to_owned();
-            $crate::compose_call_for_pallet_metadata!(pallet_metadata, $call_name $(, ($args)) *)
-        }
+			let maybe_pallet = $node_metadata.pallet_by_name($pallet_name);
+			let maybe_call = match  maybe_pallet {
+				Some(pallet) => {
+					$crate::compose_call_for_pallet_metadata!(pallet, $call_name $(, ($args)) *)
+				},
+				None => None,
+			};
+			maybe_call
+		}
+
     };
 }
 
@@ -54,13 +61,19 @@ macro_rules! compose_call {
 macro_rules! compose_call_for_pallet_metadata {
 ($pallet_metadata: expr, $call_name: expr $(, $args: expr) *) => {
         {
-            let call_index = $pallet_metadata.call_variant_by_name($call_name).unwrap().index;
-            ([$pallet_metadata.index(), call_index as u8] $(, ($args)) *)
+
+			let maybe_call_variant = $pallet_metadata.call_variant_by_name($call_name);
+			match maybe_call_variant {
+				Some(call_variant) => Some(([$pallet_metadata.index(), call_variant.index as u8] $(, ($args)) *)),
+				None => None,
+			}
+
         }
+
     };
 }
 
-/// Generates an Unchecked extrinsic for a given call
+/// Generates an UncheckedExtrinsic for a given call.
 /// # Arguments
 ///
 /// * 'signer' - AccountKey that is used to sign the extrinsic.
@@ -85,75 +98,87 @@ macro_rules! compose_extrinsic_offline {
 	}};
 }
 
-/// Generates an Unchecked extrinsic for a given module and call passed as a &str.
+/// Generates an UncheckedExtrinsic for the given pallet and call, if they are found within the metadata.
+/// Otherwise None is returned.
 /// # Arguments
 ///
 /// * 'api' - This instance of API. If the *signer* field is not set, an unsigned extrinsic will be generated.
 /// * 'nonce' - signer's account nonce: Index
-/// * 'module' - Module name as &str for which the call is composed.
-/// * 'call' - Call name as &str
+/// * 'pallet_name' - Pallet name as &str for which the call is composed.
+/// * 'call_name' - Call name as &str
 /// * 'args' - Optional sequence of arguments of the call. They are not checked against the metadata.
-/// As of now the user needs to check himself that the correct arguments are supplied.
 #[macro_export]
 macro_rules! compose_extrinsic_with_nonce {
 	($api: expr,
 	$nonce: expr,
-	$module: expr,
-	$call: expr
+	$pallet_name: expr,
+	$call_name: expr
 	$(, $args: expr) *) => {
 		{
             use $crate::log::debug;
             use $crate::primitives::UncheckedExtrinsicV4;
 
-            debug!("Composing generic extrinsic for module {:?} and call {:?}", $module, $call);
+            debug!("Composing generic extrinsic for module {:?} and call {:?}", $pallet_name, $call_name);
 
 			let metadata = $api.metadata();
-            let call = $crate::compose_call!(metadata, $module, $call $(, ($args)) *);
-            if let Some(signer) = $api.signer() {
-                $crate::compose_extrinsic_offline!(
-                    signer,
-                    call.clone(),
-                    $api.extrinsic_params($nonce)
-                )
-            } else {
-                UncheckedExtrinsicV4::new_unsigned(call.clone())
-            }
+            let maybe_call = $crate::compose_call!(metadata, $pallet_name, $call_name $(, ($args)) *);
+
+			let maybe_extrinsic = match maybe_call {
+				Some(call) => {
+					let extrinsic = if let Some(signer) = $api.signer() {
+						$crate::compose_extrinsic_offline!(
+							signer,
+							call.clone(),
+							$api.extrinsic_params($nonce)
+						)
+					} else {
+						UncheckedExtrinsicV4::new_unsigned(call.clone())
+					};
+					Some(extrinsic)
+				},
+				None => None,
+			};
+			maybe_extrinsic
+
+
 		}
 	};
 }
 
-/// Generates an Unchecked extrinsic for a given module and call passed as a &str.
-/// Fetches the nonce from the given `api` instance
+/// Generates an UncheckedExtrinsic for the given pallet and call, if they are found within the metadata.
+/// Otherwise None is returned.
+/// Fetches the nonce from the given `api` instance. If this fails, zero is taken as default nonce.
 /// See also compose_extrinsic_with_nonce
 #[macro_export]
 #[cfg(feature = "sync-api")]
 macro_rules! compose_extrinsic {
 	($api: expr,
-	$module: expr,
-	$call: expr
+	$pallet_name: expr,
+	$call_name: expr
 	$(, $args: expr) *) => {
 		{
-			let nonce = $api.get_nonce().unwrap();
-			let extrinsic = $crate::compose_extrinsic_with_nonce!($api, nonce, $module, $call $(, ($args)) *);
-			extrinsic
+			let nonce = $api.get_nonce().unwrap_or_default();
+			let maybe_extrinisc = $crate::compose_extrinsic_with_nonce!($api, nonce, $pallet_name, $call_name $(, ($args)) *);
+			maybe_extrinisc
 		}
     };
 }
 
-/// Generates an Unchecked extrinsic for a given module and call passed as a &str.
-/// Fetches the nonce from the given `api` instance
+/// Generates an UncheckedExtrinsic for the given pallet and call, if they are found within the metadata.
+/// Otherwise None is returned.
+/// Fetches the nonce from the given `api` instance. If this fails, zero is taken as default nonce.
 /// See also compose_extrinsic_with_nonce
 #[macro_export]
 #[cfg(not(feature = "sync-api"))]
 macro_rules! compose_extrinsic {
 	($api: expr,
-	$module: expr,
-	$call: expr
+	$pallet_name: expr,
+	$call_name: expr
 	$(, $args: expr) *) => {
 		{
-			let nonce = $api.get_nonce().await.unwrap();
-			let extrinsic = $crate::compose_extrinsic_with_nonce!($api, nonce, $module, $call $(, ($args)) *);
-			extrinsic
+			let nonce = $api.get_nonce().await.unwrap_or_default();
+			let maybe_extrinisc = $crate::compose_extrinsic_with_nonce!($api, nonce, $pallet_name, $call_name $(, ($args)) *);
+			maybe_extrinisc
 		}
 	};
 }
@@ -181,14 +206,75 @@ mod tests {
 			&pallet_metadata,
 			"transfer_allow_death",
 			extra_parameter
-		);
+		)
+		.unwrap();
 		assert_eq!(expected_call_one, call_one);
 		let expected_call_two = ([4, 8], extra_parameter);
 		let call_two = compose_call_for_pallet_metadata!(
 			&pallet_metadata,
 			"force_set_balance",
 			extra_parameter
-		);
+		)
+		.unwrap();
 		assert_eq!(expected_call_two, call_two);
 	}
+
+	#[test]
+	fn macro_compose_call_for_pallet_metadata_returns_none_for_unknown_function() {
+		let encoded_metadata = fs::read("../ksm_metadata_v14.bin").unwrap();
+		let runtime_metadata_prefixed =
+			RuntimeMetadataPrefixed::decode(&mut encoded_metadata.as_slice()).unwrap();
+		let metadata = Metadata::try_from(runtime_metadata_prefixed).unwrap();
+
+		let pallet_metadata = metadata.pallet_by_name("Balances").unwrap();
+		let non_existent_function = "obladi";
+
+		let option = compose_call_for_pallet_metadata!(&pallet_metadata, non_existent_function);
+		assert!(option.is_none());
+	}
+
+	#[test]
+	fn macro_compose_call_returns_none_for_unknown_function() {
+		let encoded_metadata = fs::read("../ksm_metadata_v14.bin").unwrap();
+		let runtime_metadata_prefixed =
+			RuntimeMetadataPrefixed::decode(&mut encoded_metadata.as_slice()).unwrap();
+		let metadata = Metadata::try_from(runtime_metadata_prefixed).unwrap();
+
+		let pallet_name = "Balances";
+		let non_existent_function = "obladi";
+
+		let option = compose_call!(&metadata, pallet_name, non_existent_function);
+		assert!(option.is_none());
+	}
+
+	#[test]
+	fn macro_compose_call_returns_none_for_unknown_pallet() {
+		let encoded_metadata = fs::read("../ksm_metadata_v14.bin").unwrap();
+		let runtime_metadata_prefixed =
+			RuntimeMetadataPrefixed::decode(&mut encoded_metadata.as_slice()).unwrap();
+		let metadata = Metadata::try_from(runtime_metadata_prefixed).unwrap();
+
+		let pallet_name = "Balance";
+		let non_existent_function = "force_set_balance";
+
+		let option = compose_call!(&metadata, pallet_name, non_existent_function);
+		assert!(option.is_none());
+	}
+
+	#[test]
+	fn macro_compose_call_works_for_valid_input() {
+		let encoded_metadata = fs::read("../ksm_metadata_v14.bin").unwrap();
+		let runtime_metadata_prefixed =
+			RuntimeMetadataPrefixed::decode(&mut encoded_metadata.as_slice()).unwrap();
+		let metadata = Metadata::try_from(runtime_metadata_prefixed).unwrap();
+
+		let pallet_name = "Balances";
+		let non_existent_function = "force_set_balance";
+		let extra_parameter = 10000;
+
+		let expected_call = ([4, 8], extra_parameter);
+		let call =
+			compose_call!(&metadata, pallet_name, non_existent_function, extra_parameter).unwrap();
+		assert_eq!(call, expected_call);
+	}
 }

examples/async/examples/check_extrinsic_events.rs

@@ -53,8 +53,10 @@ async fn main() {
 	// So lets create an extrinsic that will not succeed:
 	// Alice tries so transfer all her balance, but that will not work, because
 	// she will not have enough balance left to pay the fees.
-	let bad_transfer_extrinsic =
-		api.balance_transfer_allow_death(bob.clone().into(), balance_of_alice).await;
+	let bad_transfer_extrinsic = api
+		.balance_transfer_allow_death(bob.clone().into(), balance_of_alice)
+		.await
+		.unwrap();
 	println!("[+] Composed extrinsic: {bad_transfer_extrinsic:?}\n",);
 
 	// Send and watch extrinsic until InBlock.
@@ -87,8 +89,10 @@ async fn main() {
 
 	// Next, we send an extrinsic that should succeed:
 	let balance_to_transfer = 1000;
-	let good_transfer_extrinsic =
-		api.balance_transfer_allow_death(bob.clone().into(), balance_to_transfer).await;
+	let good_transfer_extrinsic = api
+		.balance_transfer_allow_death(bob.clone().into(), balance_to_transfer)
+		.await
+		.unwrap();
 	// Send and watch extrinsic until InBlock.
 	let result = api
 		.submit_and_watch_extrinsic_until(good_transfer_extrinsic, XtStatus::InBlock)

examples/async/examples/compose_extrinsic.rs

@@ -103,7 +103,8 @@ async fn main() {
 			"transfer_allow_death",
 			recipients_extrinsic_address,
 			Compact(4u32)
-		);
+		)
+		.unwrap();
 		compose_extrinsic_offline!(extrinsic_signer, call, extrinsic_params)
 	};
 

examples/async/examples/contract_instantiate_with_code.rs

@@ -63,7 +63,8 @@ async fn main() {
 
 	let xt = api
 		.contract_instantiate_with_code(1_000_000_000_000_000, 500_000, wasm, vec![1u8], vec![1u8])
-		.await;
+		.await
+		.unwrap();
 
 	println!("[+] Creating a contract instance with extrinsic:\n\n{:?}\n", xt);
 	let report = api.submit_and_watch_extrinsic_until(xt, XtStatus::InBlock).await.unwrap();
@@ -83,7 +84,7 @@ async fn main() {
 	let contract = contract_instantiated_events[0].contract.clone();
 	println!("[+] Event was received. Contract deployed at: {contract:?}\n");
 
-	let xt = api.contract_call(contract.into(), 500_000, 500_000, vec![0u8]).await;
+	let xt = api.contract_call(contract.into(), 500_000, 500_000, vec![0u8]).await.unwrap();
 
 	println!("[+] Calling the contract with extrinsic Extrinsic:\n{:?}\n\n", xt);
 	let report = api.submit_and_watch_extrinsic_until(xt, XtStatus::Finalized).await.unwrap();

examples/async/examples/get_account_identity.rs

@@ -62,7 +62,7 @@ async fn main() {
 	};
 
 	let xt: UncheckedExtrinsicV4<_, _, _, _> =
-		compose_extrinsic!(&api, "Identity", "set_identity", Box::new(info.clone()));
+		compose_extrinsic!(&api, "Identity", "set_identity", Box::new(info.clone())).unwrap();
 	println!("[+] Composed Extrinsic:\n {:?}\n", xt);
 
 	// Send and watch extrinsic until InBlock.

examples/async/examples/query_runtime_api.rs

@@ -44,7 +44,8 @@ async fn main() {
 
 	// Query the fee of an extrinsic.
 	let bob = AccountKeyring::Bob.to_account_id();
-	let balance_extrinsic = api.balance_transfer_allow_death(bob.clone().into(), 1000).await;
+	let balance_extrinsic =
+		api.balance_transfer_allow_death(bob.clone().into(), 1000).await.unwrap();
 	let extrinsic_fee_details = runtime_api
 		.query_fee_details(balance_extrinsic.clone(), 1000, None)
 		.await

examples/async/examples/runtime_update_async.rs

@@ -80,9 +80,9 @@ pub async fn send_code_update_extrinsic(
 	let new_wasm: &[u8] = include_bytes!("kitchensink_runtime.compact.compressed.wasm");
 
 	// this call can only be called by sudo
-	let call = compose_call!(api.metadata(), "System", "set_code", new_wasm.to_vec());
+	let call = compose_call!(api.metadata(), "System", "set_code", new_wasm.to_vec()).unwrap();
 	let weight: Weight = 0.into();
-	let xt = compose_extrinsic!(&api, "Sudo", "sudo_unchecked_weight", call, weight);
+	let xt = compose_extrinsic!(&api, "Sudo", "sudo_unchecked_weight", call, weight).unwrap();
 
 	println!("Sending extrinsic to trigger runtime update");
 	let block_hash = api

examples/async/examples/staking_batch_payout.rs

@@ -73,7 +73,7 @@ async fn main() {
 	// error is returned from the node, the extrinsic has been created correctly.
 	// Sidenote: We could theoretically force a new era with sudo, but this takes at least 10 minutes ( = 1 epoch) in the
 	// kitchensink rutime. We don't want to wait that long.
-	let payout_staker_xt = api.payout_stakers(0, validator_stash).await;
+	let payout_staker_xt = api.payout_stakers(0, validator_stash).await.unwrap();
 	let result = api.submit_and_watch_extrinsic_until(payout_staker_xt, XtStatus::InBlock).await;
 	assert!(result.is_err());
 	assert!(format!("{result:?}").contains("InvalidEraToReward"));
@@ -123,16 +123,18 @@ async fn main() {
 
 				if exposure.total.to_be_bytes() > 0_u128.to_be_bytes() && is_grace_period_satisfied
 				{
-					let payout_extrinsic =
-						api.payout_stakers(payout_era_index, validator_account.clone()).await;
+					let payout_extrinsic = api
+						.payout_stakers(payout_era_index, validator_account.clone())
+						.await
+						.unwrap();
 					payout_calls.push(payout_extrinsic.function);
 				}
 				i += 1;
 				last_reward_received_at_era += 1;
 			}
 			num_of_claimed_payouts += payout_calls.len();
 			num_of_unclaimed_payouts -= tx_limit_in_current_batch;
-			let batch_xt = api.batch(payout_calls).await;
+			let batch_xt = api.batch(payout_calls).await.unwrap();
 
 			let report =
 				api.submit_and_watch_extrinsic_until(batch_xt, XtStatus::InBlock).await.unwrap();