refactor: Move restorewallet() RPC logic to the wallet section

It also simplifies restorewallet() and loadwallet() RPC error handling.

src/rpc/protocol.h

@@ -80,6 +80,7 @@ enum RPCErrorCode
     RPC_WALLET_NOT_FOUND            = -18, //!< Invalid wallet specified
     RPC_WALLET_NOT_SPECIFIED        = -19, //!< No wallet specified (error when there are multiple wallets loaded)
     RPC_WALLET_ALREADY_LOADED       = -35, //!< This same wallet is already loaded
+    RPC_WALLET_ALREADY_EXISTS       = -36, //!< There is already a wallet with the same name
 
     //! Backwards compatible aliases
     RPC_WALLET_INVALID_ACCOUNT_NAME = RPC_WALLET_INVALID_LABEL_NAME,

src/wallet/db.h

@@ -220,6 +220,7 @@ enum class DatabaseStatus {
     FAILED_LOAD,
     FAILED_VERIFY,
     FAILED_ENCRYPT,
+    FAILED_INVALID_BACKUP_FILE,
 };
 
 /** Recursively list database paths in directory. */

src/wallet/rpc/backup.cpp

@@ -1879,27 +1879,17 @@ RPCHelpMan restorewallet()
 
     auto backup_file = fs::u8path(request.params[1].get_str());
 
-    if (!fs::exists(backup_file)) {
-        throw JSONRPCError(RPC_INVALID_PARAMETER, "Backup file does not exist");
-    }
-
     std::string wallet_name = request.params[0].get_str();
 
-    const fs::path wallet_path = fsbridge::AbsPathJoin(GetWalletDir(), fs::u8path(wallet_name));
+    std::optional<bool> load_on_start = request.params[2].isNull() ? std::nullopt : std::optional<bool>(request.params[2].get_bool());
 
-    if (fs::exists(wallet_path)) {
+    DatabaseStatus status;
-        throw JSONRPCError(RPC_INVALID_PARAMETER, "Wallet name already exists.");
+    bilingual_str error;
-    }
+    std::vector<bilingual_str> warnings;
 
-    if (!TryCreateDirectories(wallet_path)) {
+    const std::shared_ptr<CWallet> wallet = RestoreWallet(context, fs::PathToString(backup_file), wallet_name, load_on_start, status, error, warnings);
-        throw JSONRPCError(RPC_WALLET_ERROR, strprintf("Failed to create database path '%s'. Database already exists.", wallet_path.u8string()));
-    }
 
-    auto wallet_file = wallet_path / "wallet.dat";
+    HandleWalletError(wallet, status, error);
-
-    fs::copy_file(backup_file, wallet_file, fs::copy_option::fail_if_exists);
-
-    auto [wallet, warnings] = LoadWalletHelper(context, request.params[2], wallet_name);
 
     UniValue obj(UniValue::VOBJ);
     obj.pushKV("name", wallet->GetName());

src/wallet/rpc/util.cpp

@@ -122,16 +122,8 @@ std::string LabelFromValue(const UniValue& value)
     return label;
 }
 
-std::tuple<std::shared_ptr<CWallet>, std::vector<bilingual_str>> LoadWalletHelper(WalletContext& context, UniValue load_on_start_param, const std::string wallet_name)
+void HandleWalletError(const std::shared_ptr<CWallet> wallet, DatabaseStatus& status, bilingual_str& error)
 {
-    DatabaseOptions options;
-    DatabaseStatus status;
-    options.require_existing = true;
-    bilingual_str error;
-    std::vector<bilingual_str> warnings;
-    std::optional<bool> load_on_start = load_on_start_param.isNull() ? std::nullopt : std::optional<bool>(load_on_start_param.get_bool());
-    std::shared_ptr<CWallet> const wallet = LoadWallet(context, wallet_name, load_on_start, options, status, error, warnings);
-
     if (!wallet) {
         // Map bad format to not found, since bad format is returned when the
         // wallet directory exists, but doesn't contain a data file.
@@ -144,11 +136,15 @@ std::tuple<std::shared_ptr<CWallet>, std::vector<bilingual_str>> LoadWalletHelpe
             case DatabaseStatus::FAILED_ALREADY_LOADED:
                 code = RPC_WALLET_ALREADY_LOADED;
                 break;
+            case DatabaseStatus::FAILED_ALREADY_EXISTS:
+                code = RPC_WALLET_ALREADY_EXISTS;
+                break;
+            case DatabaseStatus::FAILED_INVALID_BACKUP_FILE:
+                code = RPC_INVALID_PARAMETER;
+                break;
             default: // RPC_WALLET_ERROR is returned for all other cases.
                 break;
         }
         throw JSONRPCError(code, error.original);
     }
-
+}
-    return { wallet, warnings };
-}

src/wallet/rpc/util.h

@@ -12,6 +12,7 @@
 
 struct bilingual_str;
 class CWallet;
+enum class DatabaseStatus;
 class JSONRPCRequest;
 class LegacyScriptPubKeyMan;
 class UniValue;
@@ -37,6 +38,6 @@ bool GetAvoidReuseFlag(const CWallet& wallet, const UniValue& param);
 bool ParseIncludeWatchonly(const UniValue& include_watchonly, const CWallet& wallet);
 std::string LabelFromValue(const UniValue& value);
 
-std::tuple<std::shared_ptr<CWallet>, std::vector<bilingual_str>> LoadWalletHelper(WalletContext& context, UniValue load_on_start_param, const std::string wallet_name);
+void HandleWalletError(const std::shared_ptr<CWallet> wallet, DatabaseStatus& status, bilingual_str& error);
 
 #endif // BITCOIN_WALLET_RPC_UTIL_H

src/wallet/rpc/wallet.cpp

@@ -215,7 +215,15 @@ static RPCHelpMan loadwallet()
     WalletContext& context = EnsureWalletContext(request.context);
     const std::string name(request.params[0].get_str());
 
-    auto [wallet, warnings] = LoadWalletHelper(context, request.params[1], name);
+    DatabaseOptions options;
+    DatabaseStatus status;
+    options.require_existing = true;
+    bilingual_str error;
+    std::vector<bilingual_str> warnings;
+    std::optional<bool> load_on_start = request.params[1].isNull() ? std::nullopt : std::optional<bool>(request.params[1].get_bool());
+    std::shared_ptr<CWallet> const wallet = LoadWallet(context, name, load_on_start, options, status, error, warnings);
+
+    HandleWalletError(wallet, status, error);
 
     UniValue obj(UniValue::VOBJ);
     obj.pushKV("name", wallet->GetName());

src/wallet/wallet.cpp

@@ -364,7 +364,7 @@ std::shared_ptr<CWallet> RestoreWallet(WalletContext& context, const std::string
 
     if (!fs::exists(fs::u8path(backup_file))) {
         error = Untranslated("Backup file does not exist");
-        status = DatabaseStatus::FAILED_BAD_PATH;
+        status = DatabaseStatus::FAILED_INVALID_BACKUP_FILE;
         return nullptr;
     }
 

test/functional/wallet_backup.py

@@ -115,12 +115,16 @@ class WalletBackupTest(BitcoinTestFramework):
         nonexistent_wallet_file = os.path.join(self.nodes[0].datadir, 'nonexistent_wallet.bak')
         wallet_name = "res0"
         assert_raises_rpc_error(-8, "Backup file does not exist", node.restorewallet, wallet_name, nonexistent_wallet_file)
+        not_created_wallet_file = os.path.join(node.datadir, self.chain, 'wallets', wallet_name)
+        assert not os.path.exists(not_created_wallet_file)
 
     def restore_wallet_existent_name(self):
         node = self.nodes[3]
-        wallet_file = os.path.join(self.nodes[0].datadir, 'wallet.bak')
+        backup_file = os.path.join(self.nodes[0].datadir, 'wallet.bak')
         wallet_name = "res0"
-        assert_raises_rpc_error(-8, "Wallet name already exists.", node.restorewallet, wallet_name, wallet_file)
+        wallet_file = os.path.join(node.datadir, self.chain, 'wallets', wallet_name)
+        error_message = "Failed to create database path '{}'. Database already exists.".format(wallet_file)
+        assert_raises_rpc_error(-36, error_message, node.restorewallet, wallet_name, backup_file)
 
     def init_three(self):
         self.init_wallet(node=0)