nix store ping: Report Nix daemon version

Fixes #5952.

1 files changed, 13 insertions, 1 deletions

diff --git a/src/libstore/remote-store.cc b/src/libstore/remote-store.cc
index aac2965e0..573becfbd 100644
--- a/src/libstore/remote-store.cc
+++ b/src/libstore/remote-store.cc
@@ -188,7 +188,12 @@ void RemoteStore::initConnection(Connection & conn)
         }
 
         if (GET_PROTOCOL_MINOR(conn.daemonVersion) >= 11)
-            conn.to << false;
+            conn.to << false; // obsolete reserveSpace
+
+        if (GET_PROTOCOL_MINOR(conn.daemonVersion) >= 33) {
+            conn.to.flush();
+            conn.daemonNixVersion = readString(conn.from);
+        }
 
         auto ex = conn.processStderr();
         if (ex) std::rethrow_exception(ex);
@@ -920,6 +925,13 @@ void RemoteStore::addBuildLog(const StorePath & drvPath, std::string_view log)
 }
 
 
+std::optional<std::string> RemoteStore::getVersion()
+{
+    auto conn(getConnection());
+    return conn->daemonNixVersion;
+}
+
+
 void RemoteStore::connect()
 {
     auto conn(getConnection());