[NFTs] Add minting price to the pre-signed mint object

frame/nfts/src/benchmarking.rs

@@ -828,6 +828,7 @@ benchmarks_instance_pallet! {
 			metadata: metadata.clone(),
 			only_account: None,
 			deadline: One::one(),
+			mint_price: Some(DepositBalanceOf::<T, I>::min_value()),
 		};
 		let message = Encode::encode(&mint_data);
 		let signature = MultiSignature::Sr25519(sr25519_sign(0.into(), &caller_public, &message).unwrap());

frame/nfts/src/features/create_delete_item.rs

@@ -16,7 +16,7 @@
 // limitations under the License.
 
 use crate::*;
-use frame_support::pallet_prelude::*;
+use frame_support::{pallet_prelude::*, traits::ExistenceRequirement};
 
 impl<T: Config<I>, I: 'static> Pallet<T, I> {
 	pub fn do_mint(
@@ -91,8 +91,15 @@ impl<T: Config<I>, I: 'static> Pallet<T, I> {
 		mint_data: PreSignedMintOf<T, I>,
 		signer: T::AccountId,
 	) -> DispatchResult {
-		let PreSignedMint { collection, item, attributes, metadata, deadline, only_account } =
-			mint_data;
+		let PreSignedMint {
+			collection,
+			item,
+			attributes,
+			metadata,
+			deadline,
+			only_account,
+			mint_price,
+		} = mint_data;
 		let metadata = Self::construct_metadata(metadata)?;
 
 		ensure!(
@@ -118,7 +125,17 @@ impl<T: Config<I>, I: 'static> Pallet<T, I> {
 			Some(mint_to.clone()),
 			mint_to.clone(),
 			item_config,
-			|_, _| Ok(()),
+			|collection_details, _| {
+				if let Some(price) = mint_price {
+					T::Currency::transfer(
+						&mint_to,
+						&collection_details.owner,
+						price,
+						ExistenceRequirement::KeepAlive,
+					)?;
+				}
+				Ok(())
+			},
 		)?;
 		let admin_account = Self::find_account_by_role(&collection, CollectionRole::Admin);
 		if let Some(admin_account) = admin_account {

frame/nfts/src/tests.rs

@@ -3146,13 +3146,14 @@ fn validate_signature() {
 		let user_1_pair = sp_core::sr25519::Pair::from_string("//Alice", None).unwrap();
 		let user_1_signer = MultiSigner::Sr25519(user_1_pair.public());
 		let user_1 = user_1_signer.clone().into_account();
-		let mint_data: PreSignedMint<u32, u32, AccountId, u32> = PreSignedMint {
+		let mint_data: PreSignedMint<u32, u32, AccountId, u32, u64> = PreSignedMint {
 			collection: 0,
 			item: 0,
 			attributes: vec![],
 			metadata: vec![],
 			only_account: None,
 			deadline: 100000,
+			mint_price: None,
 		};
 		let encoded_data = Encode::encode(&mint_data);
 		let signature = MultiSignature::Sr25519(user_1_pair.sign(&encoded_data));
@@ -3182,6 +3183,7 @@ fn pre_signed_mints_should_work() {
 			metadata: vec![0, 1],
 			only_account: None,
 			deadline: 10000000,
+			mint_price: Some(10),
 		};
 		let message = Encode::encode(&mint_data);
 		let signature = MultiSignature::Sr25519(user_1_pair.sign(&message));
@@ -3228,8 +3230,8 @@ fn pre_signed_mints_should_work() {
 		assert_eq!(deposit.account, Some(user_2.clone()));
 		assert_eq!(deposit.amount, 3);
 
-		assert_eq!(Balances::free_balance(&user_0), 100 - 2); // 2 - collection deposit
-		assert_eq!(Balances::free_balance(&user_2), 100 - 1 - 3 - 6); // 1 - item deposit, 3 - metadata, 6 - attributes
+		assert_eq!(Balances::free_balance(&user_0), 100 - 2 + 10); // 2 - collection deposit, 10 - mint price
+		assert_eq!(Balances::free_balance(&user_2), 100 - 1 - 3 - 6 - 10); // 1 - item deposit, 3 - metadata, 6 - attributes, 10 - mint price
 
 		assert_noop!(
 			Nfts::mint_pre_signed(
@@ -3242,7 +3244,7 @@ fn pre_signed_mints_should_work() {
 		);
 
 		assert_ok!(Nfts::burn(RuntimeOrigin::signed(user_2.clone()), 0, 0));
-		assert_eq!(Balances::free_balance(&user_2), 100 - 6);
+		assert_eq!(Balances::free_balance(&user_2), 100 - 6 - 10);
 
 		// validate the `only_account` field
 		let mint_data = PreSignedMint {
@@ -3252,6 +3254,7 @@ fn pre_signed_mints_should_work() {
 			metadata: vec![],
 			only_account: Some(account(2)),
 			deadline: 10000000,
+			mint_price: None,
 		};
 
 		// can't mint with the wrong signature
@@ -3299,6 +3302,7 @@ fn pre_signed_mints_should_work() {
 			metadata: vec![],
 			only_account: Some(account(2)),
 			deadline: 10000000,
+			mint_price: None,
 		};
 		let message = Encode::encode(&mint_data);
 		let signature = MultiSignature::Sr25519(user_1_pair.sign(&message));
@@ -3321,6 +3325,7 @@ fn pre_signed_mints_should_work() {
 			metadata: vec![0, 1],
 			only_account: None,
 			deadline: 10000000,
+			mint_price: None,
 		};
 		let message = Encode::encode(&mint_data);
 		let signature = MultiSignature::Sr25519(user_1_pair.sign(&message));

frame/nfts/src/types.rs

@@ -66,6 +66,7 @@ pub(super) type PreSignedMintOf<T, I = ()> = PreSignedMint<
 	<T as Config<I>>::ItemId,
 	<T as SystemConfig>::AccountId,
 	<T as SystemConfig>::BlockNumber,
+	BalanceOf<T, I>,
 >;
 pub(super) type PreSignedAttributesOf<T, I = ()> = PreSignedAttributes<
 	<T as Config<I>>::CollectionId,
@@ -506,7 +507,7 @@ impl CollectionRoles {
 impl_codec_bitflags!(CollectionRoles, u8, CollectionRole);
 
 #[derive(Clone, Eq, PartialEq, Encode, Decode, RuntimeDebug, TypeInfo)]
-pub struct PreSignedMint<CollectionId, ItemId, AccountId, Deadline> {
+pub struct PreSignedMint<CollectionId, ItemId, AccountId, Deadline, Balance> {
 	/// A collection of the item to be minted.
 	pub(super) collection: CollectionId,
 	/// Item's ID.
@@ -519,6 +520,8 @@ pub struct PreSignedMint<CollectionId, ItemId, AccountId, Deadline> {
 	pub(super) only_account: Option<AccountId>,
 	/// A deadline for the signature.
 	pub(super) deadline: Deadline,
+	/// An optional price the claimer would need to pay for the mint.
+	pub(super) mint_price: Option<Balance>,
 }
 
 #[derive(Clone, Eq, PartialEq, Encode, Decode, RuntimeDebug, TypeInfo)]