refactor: remove read state encoding (#122)

Co-authored-by: Frank Bell <frank@r0gue.io>

pallets/api/src/fungibles/mod.rs

@@ -180,61 +180,33 @@ pub mod pallet {
 	}
 
 	impl<T: Config> Pallet<T> {
-		/// Returns the total token supply for a given asset ID.
+		/// Reads fungible asset state based on the provided value.
 		///
-		/// # Parameters
-		/// * `id` - The ID of the asset.
-		pub fn total_supply(id: AssetIdOf<T>) -> BalanceOf<T> {
-			AssetsOf::<T>::total_supply(id)
-		}
-
-		/// Returns the account balance for the specified `owner` for a given asset ID. Returns `0` if
-		/// the account is non-existent.
+		/// This function matches the value to determine the type of state query and returns the
+		/// encoded result.
 		///
-		/// # Parameters
-		/// * `id` - The ID of the asset.
-		/// * `owner` - The account whose balance is being queried.
-		pub fn balance_of(id: AssetIdOf<T>, owner: &AccountIdOf<T>) -> BalanceOf<T> {
-			AssetsOf::<T>::balance(id, owner)
-		}
-
-		/// Returns the amount which `spender` is still allowed to withdraw from `owner` for a given
-		/// asset ID. Returns `0` if no allowance has been set.
-		///
-		/// # Parameters
-		/// * `id` - The ID of the asset.
-		/// * `owner` - The account that owns the tokens.
-		/// * `spender` - The account that is allowed to spend the tokens.
-		pub fn allowance(
-			id: AssetIdOf<T>,
-			owner: &AccountIdOf<T>,
-			spender: &AccountIdOf<T>,
-		) -> BalanceOf<T> {
-			AssetsOf::<T>::allowance(id, owner, spender)
-		}
-
-		/// Returns the token name for a given asset ID.
-		///
-		/// # Parameters
-		/// * `id` - The ID of the asset.
-		pub fn token_name(id: AssetIdOf<T>) -> Vec<u8> {
-			<AssetsOf<T> as MetadataInspect<AccountIdOf<T>>>::name(id)
-		}
-
-		/// Returns the token symbol for a given asset ID.
-		///
-		/// # Parameters
-		/// * `id` - The ID of the asset.
-		pub fn token_symbol(id: AssetIdOf<T>) -> Vec<u8> {
-			<AssetsOf<T> as MetadataInspect<AccountIdOf<T>>>::symbol(id)
-		}
-
-		/// Returns the token decimals for a given asset ID.
-		///
-		/// # Parameters
-		/// * `id` - The ID of the asset.
-		pub fn token_decimals(id: AssetIdOf<T>) -> u8 {
-			<AssetsOf<T> as MetadataInspect<AccountIdOf<T>>>::decimals(id)
+		/// # Parameter
+		/// * `value` - An instance of `Read<T>`, which specifies the type of state query and
+		/// 		  the associated parameters.
+		pub fn read_state(value: Read<T>) -> Vec<u8> {
+			use Read::*;
+
+			match value {
+				TotalSupply(id) => AssetsOf::<T>::total_supply(id).encode(),
+				BalanceOf { id, owner } => AssetsOf::<T>::balance(id, owner).encode(),
+				Allowance { id, owner, spender } => {
+					AssetsOf::<T>::allowance(id, &owner, &spender).encode()
+				},
+				TokenName(id) => {
+					<AssetsOf<T> as MetadataInspect<AccountIdOf<T>>>::name(id).encode()
+				},
+				TokenSymbol(id) => {
+					<AssetsOf<T> as MetadataInspect<AccountIdOf<T>>>::symbol(id).encode()
+				},
+				TokenDecimals(id) => {
+					<AssetsOf<T> as MetadataInspect<AccountIdOf<T>>>::decimals(id).encode()
+				},
+			}
 		}
 	}
 }

pallets/api/src/fungibles/tests.rs

@@ -1,4 +1,5 @@
-use crate::mock::*;
+use crate::{fungibles::Read::*, mock::*};
+use codec::Encode;
 use frame_support::{
 	assert_ok,
 	traits::fungibles::{approvals::Inspect, metadata::Inspect as MetadataInspect},
@@ -60,15 +61,18 @@ fn increase_allowance_works() {
 fn total_supply_works() {
 	new_test_ext().execute_with(|| {
 		create_asset_and_mint_to(ALICE, ASSET, ALICE, 100);
-		assert_eq!(Assets::total_supply(ASSET), Fungibles::total_supply(ASSET));
+		assert_eq!(Assets::total_supply(ASSET).encode(), Fungibles::read_state(TotalSupply(ASSET)));
 	});
 }
 
 #[test]
 fn balance_of_works() {
 	new_test_ext().execute_with(|| {
 		create_asset_and_mint_to(ALICE, ASSET, ALICE, 100);
-		assert_eq!(Assets::balance(ASSET, ALICE), Fungibles::balance_of(ASSET, &ALICE));
+		assert_eq!(
+			Assets::balance(ASSET, ALICE).encode(),
+			Fungibles::read_state(BalanceOf { id: ASSET, owner: ALICE })
+		);
 	});
 }
 
@@ -77,8 +81,8 @@ fn allowance_works() {
 	new_test_ext().execute_with(|| {
 		create_asset_mint_and_approve(ALICE, ASSET, BOB, 100, ALICE, 50);
 		assert_eq!(
-			Assets::allowance(ASSET, &ALICE, &BOB),
-			Fungibles::allowance(ASSET, &ALICE, &BOB)
+			Assets::allowance(ASSET, &ALICE, &BOB).encode(),
+			Fungibles::read_state(Allowance { id: ASSET, owner: ALICE, spender: BOB })
 		);
 	});
 }
@@ -90,9 +94,9 @@ fn token_metadata_works() {
 		let symbol: Vec<u8> = vec![21, 22, 23];
 		let decimals: u8 = 69;
 		create_asset_and_set_metadata(ALICE, ASSET, name.clone(), symbol.clone(), decimals);
-		assert_eq!(Assets::name(ASSET), Fungibles::token_name(ASSET));
-		assert_eq!(Assets::symbol(ASSET), Fungibles::token_symbol(ASSET));
-		assert_eq!(Assets::decimals(ASSET), Fungibles::token_decimals(ASSET));
+		assert_eq!(Assets::name(ASSET).encode(), Fungibles::read_state(TokenName(ASSET)));
+		assert_eq!(Assets::symbol(ASSET).encode(), Fungibles::read_state(TokenSymbol(ASSET)));
+		assert_eq!(Assets::decimals(ASSET).encode(), Fungibles::read_state(TokenDecimals(ASSET)));
 	});
 }
 

pop-api/src/lib.rs

@@ -1,9 +1,7 @@
 #![cfg_attr(not(feature = "std"), no_std, no_main)]
 
-use ink::env::chain_extension::ChainExtensionMethod;
-
 use constants::DECODING_FAILED;
-use ink::env::chain_extension::FromStatusCode;
+use ink::env::chain_extension::{ChainExtensionMethod, FromStatusCode};
 #[cfg(feature = "assets")]
 pub use v0::assets;
 

pop-api/src/v0/assets/fungibles.rs

@@ -1,12 +1,10 @@
-use ink::{env::chain_extension::ChainExtensionMethod, prelude::vec::Vec, scale::Decode};
-
 use crate::{
-	constants::{ASSETS, BALANCES, DECODING_FAILED, FUNGIBLES},
+	constants::{ASSETS, BALANCES, FUNGIBLES},
 	primitives::{AccountId, AssetId, Balance},
-	v0::V0,
 	Result, StatusCode,
 };
 use constants::*;
+use ink::{env::chain_extension::ChainExtensionMethod, prelude::vec::Vec};
 pub use metadata::*;
 
 /// Helper method to build a dispatch call `ChainExtensionMethod` for fungibles `v0`
@@ -78,10 +76,9 @@ mod constants {
 pub fn total_supply(id: AssetId) -> Result<Balance> {
 	build_read_state(TOTAL_SUPPLY)
 		.input::<AssetId>()
-		.output::<Result<Vec<u8>>, true>()
+		.output::<Result<Balance>, true>()
 		.handle_error_code::<StatusCode>()
 		.call(&(id))
-		.and_then(|v| Balance::decode(&mut &v[..]).map_err(|_e| StatusCode(DECODING_FAILED)))
 }
 
 /// Returns the account balance for the specified `owner` for a given asset ID. Returns `0` if
@@ -97,10 +94,9 @@ pub fn total_supply(id: AssetId) -> Result<Balance> {
 pub fn balance_of(id: AssetId, owner: AccountId) -> Result<Balance> {
 	build_read_state(BALANCE_OF)
 		.input::<(AssetId, AccountId)>()
-		.output::<Result<Vec<u8>>, true>()
+		.output::<Result<Balance>, true>()
 		.handle_error_code::<StatusCode>()
 		.call(&(id, owner))
-		.and_then(|v| Balance::decode(&mut &v[..]).map_err(|_e| StatusCode(DECODING_FAILED)))
 }
 
 /// Returns the amount which `spender` is still allowed to withdraw from `owner` for a given
@@ -117,10 +113,9 @@ pub fn balance_of(id: AssetId, owner: AccountId) -> Result<Balance> {
 pub fn allowance(id: AssetId, owner: AccountId, spender: AccountId) -> Result<Balance> {
 	build_read_state(ALLOWANCE)
 		.input::<(AssetId, AccountId, AccountId)>()
-		.output::<Result<Vec<u8>>, true>()
+		.output::<Result<Balance>, true>()
 		.handle_error_code::<StatusCode>()
 		.call(&(id, owner, spender))
-		.and_then(|v| Balance::decode(&mut &v[..]).map_err(|_e| StatusCode(DECODING_FAILED)))
 }
 
 /// Transfers `value` amount of tokens from the caller's account to account `to`, with additional
@@ -233,7 +228,6 @@ pub mod metadata {
 			.output::<Result<Vec<u8>>, true>()
 			.handle_error_code::<StatusCode>()
 			.call(&(id))
-			.and_then(|v| <Vec<u8>>::decode(&mut &v[..]).map_err(|_e| StatusCode(DECODING_FAILED)))
 	}
 
 	/// Returns the token symbol for a given asset ID.
@@ -250,7 +244,6 @@ pub mod metadata {
 			.output::<Result<Vec<u8>>, true>()
 			.handle_error_code::<StatusCode>()
 			.call(&(id))
-			.and_then(|v| <Vec<u8>>::decode(&mut &v[..]).map_err(|_e| StatusCode(DECODING_FAILED)))
 	}
 
 	/// Returns the token decimals for a given asset ID.
@@ -264,10 +257,9 @@ pub mod metadata {
 	pub fn token_decimals(id: AssetId) -> Result<u8> {
 		build_read_state(TOKEN_DECIMALS)
 			.input::<AssetId>()
-			.output::<Result<Vec<u8>>, true>()
+			.output::<Result<u8>, true>()
 			.handle_error_code::<StatusCode>()
 			.call(&(id))
-			.and_then(|v| <u8>::decode(&mut &v[..]).map_err(|_e| StatusCode(DECODING_FAILED)))
 	}
 }
 

pop-api/src/v0/assets/mod.rs

@@ -1,3 +1,2 @@
 #[cfg(feature = "fungibles")]
 pub mod fungibles;
-

runtime/devnet/src/config/api.rs

@@ -11,24 +11,37 @@ pub enum RuntimeRead<T: fungibles::Config> {
 	Fungibles(fungibles::Read<T>),
 }
 
-impl fungibles::Config for Runtime {
-	type AssetsInstance = TrustBackedAssetsInstance;
-	type WeightInfo = fungibles::weights::SubstrateWeight<Runtime>;
-}
-
-/// A type to identify allowed calls to the Runtime from contracts. Used by Pop API
+/// A type to identify allowed calls to the Runtime from the API.
 pub struct AllowedApiCalls;
 
 impl Contains<RuntimeCall> for AllowedApiCalls {
+	/// Allowed runtime calls from the API.
 	fn contains(c: &RuntimeCall) -> bool {
-		use fungibles::Call as FungiblesCall;
+		use fungibles::Call::*;
+		matches!(
+			c,
+			RuntimeCall::Fungibles(transfer { .. } | approve { .. } | increase_allowance { .. })
+		)
+	}
+}
+
+impl<T: fungibles::Config> Contains<RuntimeRead<T>> for AllowedApiCalls {
+	/// Allowed state queries from the API.
+	fn contains(c: &RuntimeRead<T>) -> bool {
+		use fungibles::Read::*;
 		matches!(
 			c,
-			RuntimeCall::Fungibles(
-				FungiblesCall::transfer { .. }
-					| FungiblesCall::approve { .. }
-					| FungiblesCall::increase_allowance { .. }
+			RuntimeRead::Fungibles(
+				TotalSupply(..)
+					| BalanceOf { .. } | Allowance { .. }
+					| TokenName(..) | TokenSymbol(..)
+					| TokenDecimals(..)
 			)
 		)
 	}
 }
+
+impl fungibles::Config for Runtime {
+	type AssetsInstance = TrustBackedAssetsInstance;
+	type WeightInfo = fungibles::weights::SubstrateWeight<Runtime>;
+}

runtime/devnet/src/extensions/v0.rs

@@ -76,7 +76,7 @@ mod tests {
 				DispatchError::Other(""),
 				(Other { dispatch_error_index: 0, error_index: 0, error: 0 }),
 			),
-			(DispatchError::Other("UnknownFunctionId"), UnknownCall),
+			(DispatchError::Other("UnknownCall"), UnknownCall),
 			(DispatchError::Other("DecodingFailed"), DecodingFailed),
 			(DispatchError::CannotLookup, CannotLookup),
 			(DispatchError::BadOrigin, BadOrigin),
@@ -120,7 +120,7 @@ mod tests {
 				DispatchError::Other("Random"),
 				(Other { dispatch_error_index: 0, error_index: 0, error: 0 }),
 			),
-			(DispatchError::Other("UnknownFunctionId"), UnknownCall),
+			(DispatchError::Other("UnknownCall"), UnknownCall),
 			(DispatchError::Other("DecodingFailed"), DecodingFailed),
 		];
 		for (dispatch_error, expected) in test_cases {