wallet_rpc_server: add a get_version RPC

src/wallet/wallet_rpc_server.cpp

@@ -2876,6 +2876,12 @@ namespace tools
     return true;
   }
   //------------------------------------------------------------------------------------------------------------------------------
+  bool wallet_rpc_server::on_get_version(const wallet_rpc::COMMAND_RPC_GET_VERSION::request& req, wallet_rpc::COMMAND_RPC_GET_VERSION::response& res, epee::json_rpc::error& er)
+  {
+    res.version = WALLET_RPC_VERSION;
+    return true;
+  }
+  //------------------------------------------------------------------------------------------------------------------------------
 }
 
 int main(int argc, char** argv) {

src/wallet/wallet_rpc_server.h

@@ -135,6 +135,7 @@ namespace tools
         MAP_JON_RPC_WE("finalize_multisig",  on_finalize_multisig,  wallet_rpc::COMMAND_RPC_FINALIZE_MULTISIG)
         MAP_JON_RPC_WE("sign_multisig",      on_sign_multisig,      wallet_rpc::COMMAND_RPC_SIGN_MULTISIG)
         MAP_JON_RPC_WE("submit_multisig",    on_submit_multisig,    wallet_rpc::COMMAND_RPC_SUBMIT_MULTISIG)
+        MAP_JON_RPC_WE("get_version",        on_get_version,        wallet_rpc::COMMAND_RPC_GET_VERSION)
       END_JSON_RPC_MAP()
     END_URI_MAP2()
 
@@ -203,6 +204,7 @@ namespace tools
       bool on_finalize_multisig(const wallet_rpc::COMMAND_RPC_FINALIZE_MULTISIG::request& req, wallet_rpc::COMMAND_RPC_FINALIZE_MULTISIG::response& res, epee::json_rpc::error& er);
       bool on_sign_multisig(const wallet_rpc::COMMAND_RPC_SIGN_MULTISIG::request& req, wallet_rpc::COMMAND_RPC_SIGN_MULTISIG::response& res, epee::json_rpc::error& er);
       bool on_submit_multisig(const wallet_rpc::COMMAND_RPC_SUBMIT_MULTISIG::request& req, wallet_rpc::COMMAND_RPC_SUBMIT_MULTISIG::response& res, epee::json_rpc::error& er);
+      bool on_get_version(const wallet_rpc::COMMAND_RPC_GET_VERSION::request& req, wallet_rpc::COMMAND_RPC_GET_VERSION::response& res, epee::json_rpc::error& er);
 
       //json rpc v2
       bool on_query_key(const wallet_rpc::COMMAND_RPC_QUERY_KEY::request& req, wallet_rpc::COMMAND_RPC_QUERY_KEY::response& res, epee::json_rpc::error& er);

src/wallet/wallet_rpc_server_commands_defs.h

@@ -39,6 +39,17 @@
 #undef MONERO_DEFAULT_LOG_CATEGORY
 #define MONERO_DEFAULT_LOG_CATEGORY "wallet.rpc"
 
+// When making *any* change here, bump minor
+// If the change is incompatible, then bump major and set minor to 0
+// This ensures WALLET_RPC_VERSION always increases, that every change
+// has its own version, and that clients can just test major to see
+// whether they can talk to a given wallet without having to know in
+// advance which version they will stop working with
+// Don't go over 32767 for any of these
+#define WALLET_RPC_VERSION_MAJOR 1
+#define WALLET_RPC_VERSION_MINOR 0
+#define MAKE_WALLET_RPC_VERSION(major,minor) (((major)<<16)|(minor))
+#define WALLET_RPC_VERSION MAKE_WALLET_RPC_VERSION(WALLET_RPC_VERSION_MAJOR, WALLET_RPC_VERSION_MINOR)
 namespace tools
 {
 namespace wallet_rpc
@@ -1848,5 +1859,23 @@ namespace wallet_rpc
     };
   };
 
+  struct COMMAND_RPC_GET_VERSION
+  {
+    struct request
+    {
+      BEGIN_KV_SERIALIZE_MAP()
+      END_KV_SERIALIZE_MAP()
+    };
+
+    struct response
+    {
+      uint32_t version;
+
+      BEGIN_KV_SERIALIZE_MAP()
+        KV_SERIALIZE(version)
+      END_KV_SERIALIZE_MAP()
+    };
+  };
+
 }
 }