wallet: No BDB creation, unless -deprecatedrpc=create_bdb

Author: MarcoFalke

src/wallet/rpc/wallet.cpp

@@ -343,7 +343,7 @@ static RPCHelpMan createwallet()
             {"passphrase", RPCArg::Type::STR, RPCArg::Optional::OMITTED, "Encrypt the wallet with this passphrase."},
             {"avoid_reuse", RPCArg::Type::BOOL, RPCArg::Default{false}, "Keep track of coin reuse, and treat dirty and clean coins differently with privacy considerations in mind."},
             {"descriptors", RPCArg::Type::BOOL, RPCArg::Default{true}, "Create a native descriptor wallet. The wallet will use descriptors internally to handle address creation."
-                                                                       " Setting to \"false\" will create a legacy wallet; however, the legacy wallet type is being deprecated and"
+                                                                       " Setting to \"false\" will create a legacy wallet; This is only possible with the -deprecatedrpc=create_bdb setting because, the legacy wallet type is being deprecated and"
                                                                        " support for creating and opening legacy wallets will be removed in the future."},
             {"load_on_startup", RPCArg::Type::BOOL, RPCArg::Optional::OMITTED, "Save wallet name to persistent settings and load on startup. True to add wallet to startup list, false to remove, null to leave unchanged."},
             {"external_signer", RPCArg::Type::BOOL, RPCArg::Default{false}, "Use an external signer such as a hardware wallet. Requires -signer to be configured. Wallet creation will fail if keys cannot be fetched. Requires disable_private_keys and descriptors set to true."},
@@ -389,11 +389,16 @@ static RPCHelpMan createwallet()
     if (!request.params[4].isNull() && request.params[4].get_bool()) {
         flags |= WALLET_FLAG_AVOID_REUSE;
     }
-    if (request.params[5].isNull() || request.params[5].get_bool()) {
+    if (self.Arg<bool>(5)) {
 #ifndef USE_SQLITE
         throw JSONRPCError(RPC_WALLET_ERROR, "Compiled without sqlite support (required for descriptor wallets)");
 #endif
         flags |= WALLET_FLAG_DESCRIPTORS;
+    } else {
+        if (!context.chain->rpcEnableDeprecated("create_bdb")) {
+            throw JSONRPCError(RPC_WALLET_ERROR, "BDB wallet creation is deprecated and will be removed in a future release."
+                                                 " In this release it can be re-enabled temporarily with the -deprecatedrpc=create_bdb setting.");
+        }
     }
     if (!request.params[7].isNull() && request.params[7].get_bool()) {
 #ifdef ENABLE_EXTERNAL_SIGNER

test/functional/test_framework/util.py

@@ -404,6 +404,7 @@ def write_config(config_path, *, n, chain, extra_config="", disable_autoconnect=
         f.write("upnp=0\n")
         f.write("natpmp=0\n")
         f.write("shrinkdebugfile=0\n")
+        f.write("deprecatedrpc=create_bdb\n")  # Required to run the tests
         # To improve SQLite wallet performance so that the tests don't timeout, use -unsafesqlitesync
         f.write("unsafesqlitesync=1\n")
         if disable_autoconnect: