Migration for contracts

frame/contracts/src/lib.rs

@@ -98,6 +98,7 @@ mod rent;
 
 #[cfg(test)]
 mod tests;
+mod migration;
 
 use crate::exec::ExecutionContext;
 use crate::account_db::{AccountDb, DirectAccountDb};
@@ -666,6 +667,10 @@ decl_module! {
 		fn on_finalize() {
 			GasSpent::kill();
 		}
+
+		fn on_runtime_upgrade() {
+			migration::on_runtime_upgrade::<T>()
+		}
 	}
 }
 

frame/contracts/src/migration.rs

@@ -0,0 +1,62 @@
+// Copyright 2020 Parity Technologies (UK) Ltd.
+// This file is part of Substrate.
+
+// Substrate is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Substrate is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Substrate.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Migration code to update storage.
+
+use super::*;
+use frame_support::storage::migration::{put_storage_value, take_storage_value, StorageIterator};
+
+pub fn on_runtime_upgrade<T: Trait>() {
+    change_name_contract_to_contracts::<T>()
+}
+
+// Change the storage name used by this pallet from `Contract` to `Contracts`.
+//
+// Since the format of the storage items themselves have not changed, we do not
+// need to keep track of a storage version. If the runtime does not need to be
+// upgraded, nothing here will happen anyway.
+
+fn change_name_contract_to_contracts<T: Trait>() {
+    sp_runtime::print("Migrating Contracts.");
+
+    if let Some(gas_spent) = take_storage_value::<Gas>(b"Contract", b"GasSpent", &[]) {
+        put_storage_value(b"Contracts", b"GasSpent", &[], gas_spent);
+    }
+
+    if let Some(current_schedule) = take_storage_value::<Schedule>(b"Contract", b"CurrentSchedule", &[]) {
+        put_storage_value(b"Contracts", b"CurrentSchedule", &[], current_schedule);
+    }
+
+    for (hash, pristine_code) in StorageIterator::<Option<Vec<u8>>>::new(b"Contract", b"PristineCode").drain() {
+        put_storage_value(b"Contracts", b"PristineCode", &hash, pristine_code);
+    }
+
+    for (hash, code_storage) in StorageIterator::<Option<wasm::PrefabWasmModule>>::new(b"Contract", b"CodeStorage").drain() {
+        put_storage_value(b"Contracts", b"CodeStorage", &hash, code_storage);
+    }
+
+    if let Some(current_schedule) = take_storage_value::<u64>(b"Contract", b"AccountCounter", &[]) {
+        put_storage_value(b"Contracts", b"AccountCounter", &[], current_schedule);
+    }
+
+    for (hash, contract_info_of) in StorageIterator::<Option<ContractInfo<T>>>::new(b"Contract", b"ContractInfoOf").drain() {
+        put_storage_value(b"Contracts", b"ContractInfoOf", &hash, contract_info_of);
+    }
+
+    if let Some(get_price) = take_storage_value::<BalanceOf<T>>(b"Contract", b"GetPrice", &[]) {
+        put_storage_value(b"Contracts", b"GetPrice", &[], get_price);
+    }
+}