Oracle

pallets/oracle/src/lib.rs

@@ -92,6 +92,7 @@ pub mod pallet {
         type RequestCost: Get<BalanceOf<Self>>;
         type RewardAmount: Get<BalanceOf<Self>>;
         type SlashAmount: Get<BalanceOf<Self>>;
+		type MaxAnswerBound: Get<u64>;
     }
 
     #[derive(Encode, Decode, Default, Debug, PartialEq)]
@@ -229,6 +230,9 @@ pub mod pallet {
         UnsetController,
         ControllerUsed,
 		SignerUsed,
+		AvoidPanic,
+		ExceedMaxAnswers,
+		InvalidMinAnswers
     }
 
     #[pallet::hooks]
@@ -244,12 +248,17 @@ pub mod pallet {
 					PrePrices::<T>::insert(i, pre_prices.clone());
                 }
                 if pre_prices.len() as u64 >= asset_info.min_answers {
-                    let price = Self::get_median_price(&pre_prices);
+					let mut slice = pre_prices;
+					// check max answer
+					if slice.len() as u64 > asset_info.max_answers {
+						 slice = slice[0 .. asset_info.max_answers as usize].to_vec();
+					}
+                    let price = Self::get_median_price(&slice);
                     let set_price = Price { price, block };
                     Prices::<T>::insert(i, set_price);
                     Requested::<T>::insert(i, false);
 					PrePrices::<T>::remove(i);
-                    Self::handle_payout(&pre_prices, price, i);
+                    Self::handle_payout(&slice, price, i);
                 }
             }
             0
@@ -274,6 +283,8 @@ pub mod pallet {
 			max_answers: u64
         ) -> DispatchResultWithPostInfo {
             T::AddOracle::ensure_origin(origin)?;
+			ensure!(max_answers <= T::MaxAnswerBound::get(), Error::<T>::ExceedMaxAnswers);
+			ensure!(min_answers > 0, Error::<T>::InvalidMinAnswers);
 			let asset_info = AssetInfo {
 				threshold,
 				min_answers,
@@ -498,6 +509,7 @@ pub mod pallet {
                 .collect();
             numbers.sort();
             let mid = numbers.len() / 2;
+			// TODO maybe check length
             numbers[mid]
         }
 
@@ -630,9 +642,7 @@ pub mod pallet {
                 }
                 _ => return None,
             };
-
-            let exp = price.fraction_length.checked_sub(2).unwrap_or(0);
-            Some(price.integer as u64 * 100 + (price.fraction / 10_u64.pow(exp)) as u64)
+            Some(price.integer as u64)
         }
     }
 }

pallets/oracle/src/mock.rs

@@ -87,6 +87,7 @@ parameter_types! {
     pub const RequestCost: u64 = 1;
     pub const RewardAmount: u64 = 5;
     pub const SlashAmount: u64 = 5;
+	pub const MaxAnswerBound: u64 = 5;
 
 }
 
@@ -135,6 +136,7 @@ impl pallet_oracle::Config for Test {
     type RequestCost = RequestCost;
     type RewardAmount = RewardAmount;
     type SlashAmount = SlashAmount;
+	type MaxAnswerBound = MaxAnswerBound;
 }
 
 // Build genesis storage according to the mock runtime.

pallets/oracle/src/tests.rs

@@ -45,6 +45,22 @@ fn add_asset_and_info() {
             Oracle::add_asset_and_info(Origin::signed(account_1), 1, Percent::from_percent(80), 3, 5),
             BadOrigin
         );
+
+		assert_noop!(Oracle::add_asset_and_info(
+            Origin::signed(account_2),
+            1,
+            Percent::from_percent(80),
+			3,
+			6,
+        ), Error::<Test>::ExceedMaxAnswers);
+
+		assert_noop!(Oracle::add_asset_and_info(
+            Origin::signed(account_2),
+            1,
+            Percent::from_percent(80),
+			0,
+			5,
+        ), Error::<Test>::InvalidMinAnswers);
     });
 }
 
@@ -529,6 +545,36 @@ fn on_init_prune_scenerios() {
     });
 }
 
+#[test]
+fn on_init_over_max_answers() {
+    new_test_ext().execute_with(|| {
+        // add and request oracle id
+        let account_2 = get_account_2();
+        assert_ok!(Oracle::add_asset_and_info(
+            Origin::signed(account_2),
+            0,
+            Percent::from_percent(80),
+			1,
+			2,
+        ));
+        let account_1: AccountId = Default::default();
+        assert_ok!(Oracle::do_request_price(&account_1, 0));
+        // set prices into storage
+        let account_1: AccountId = Default::default();
+        for i in 0..5 {
+            let price = i as u64 + 100u64;
+            add_price_storage(price, 0, account_1, 0);
+        }
+        // all pruned
+        Oracle::on_initialize(0);
+		// price prunes all but first 2 answers, median went from 102 to 101
+        let price = Price { price: 101, block: 0 };
+        assert_eq!(Oracle::prices(0), price);
+        assert_eq!(Oracle::pre_prices(0).len(), 0);
+
+});
+}
+
 #[test]
 fn prune_old_edgecase() {
     new_test_ext().execute_with(|| {
@@ -649,10 +695,8 @@ fn should_submit_signed_transaction_on_chain() {
 #[test]
 fn parse_price_works() {
     let test_data = vec![
-        ("{\"USD\":6536.92}", Some(653692)),
-        ("{\"USD\":65.92}", Some(6592)),
-        ("{\"USD\":6536.924565}", Some(653692)),
-        ("{\"USD\":6536}", Some(653600)),
+        ("{\"USD\":6536.92}", Some(6536)),
+        ("{\"USD\":650000000}", Some(650000000)),
         ("{\"USD2\":6536}", None),
         ("{\"USD\":\"6432\"}", None),
     ];

runtime/Cargo.toml

@@ -6,7 +6,7 @@ version = '2.0.0'
 
 
 [dependencies.pallet-cfgeneric]
-# import our generic pallet  
+# import our generic pallet
 default-features = false
 path = "../pallets/cfgeneric"
 optional = true

runtime/src/lib.rs

@@ -299,6 +299,7 @@ parameter_types! {
 	pub const RewardAmount: Balance = 5;
 	pub const SlashAmount: Balance = 5;
 	pub const StalePrice: BlockNumber = 5;
+	pub const MaxAnswerBound: u64 = 25;
 
 }
 
@@ -313,6 +314,7 @@ impl pallet_oracle::Config for Runtime {
 	type RequestCost = RequestCost;
 	type RewardAmount = RewardAmount;
 	type SlashAmount = SlashAmount;
+	type MaxAnswerBound = MaxAnswerBound;
 }
 
 impl<LocalCall> frame_system::offchain::CreateSignedTransaction<LocalCall> for Runtime