Remove use of CRPCTable::appendCommand in wallet code

This commit does not change behavior.

src/interfaces/chain.cpp

@@ -15,12 +15,15 @@
 #include <primitives/block.h>
 #include <primitives/transaction.h>
 #include <protocol.h>
+#include <rpc/protocol.h>
+#include <rpc/server.h>
 #include <sync.h>
 #include <threadsafety.h>
 #include <timedata.h>
 #include <txmempool.h>
 #include <ui_interface.h>
 #include <uint256.h>
+#include <univalue.h>
 #include <util/system.h>
 #include <validation.h>
 #include <validationinterface.h>
@@ -212,6 +215,45 @@ public:
     Chain::Notifications* m_notifications;
 };
 
+class RpcHandlerImpl : public Handler
+{
+public:
+    RpcHandlerImpl(const CRPCCommand& command) : m_command(command), m_wrapped_command(&command)
+    {
+        m_command.actor = [this](const JSONRPCRequest& request, UniValue& result, bool last_handler) {
+            if (!m_wrapped_command) return false;
+            try {
+                return m_wrapped_command->actor(request, result, last_handler);
+            } catch (const UniValue& e) {
+                // If this is not the last handler and a wallet not found
+                // exception was thrown, return false so the next handler can
+                // try to handle the request. Otherwise, reraise the exception.
+                if (!last_handler) {
+                    const UniValue& code = e["code"];
+                    if (code.isNum() && code.get_int() == RPC_WALLET_NOT_FOUND) {
+                        return false;
+                    }
+                }
+                throw;
+            }
+        };
+        ::tableRPC.appendCommand(m_command.name, &m_command);
+    }
+
+    void disconnect() override final
+    {
+        if (m_wrapped_command) {
+            m_wrapped_command = nullptr;
+            ::tableRPC.removeCommand(m_command.name, &m_command);
+        }
+    }
+
+    ~RpcHandlerImpl() override { disconnect(); }
+
+    CRPCCommand m_command;
+    const CRPCCommand* m_wrapped_command;
+};
+
 class ChainImpl : public Chain
 {
 public:
@@ -310,8 +352,11 @@ public:
         return MakeUnique<NotificationsHandlerImpl>(*this, notifications);
     }
     void waitForNotifications() override { SyncWithValidationInterfaceQueue(); }
+    std::unique_ptr<Handler> handleRpc(const CRPCCommand& command) override
+    {
+        return MakeUnique<RpcHandlerImpl>(command);
+    }
 };
-
 } // namespace
 
 std::unique_ptr<Chain> MakeChain() { return MakeUnique<ChainImpl>(); }