libstore: remove operations that are never called by supported clients

I did a whole bunch of `git log -S` to find out exactly when all these
things were obsoleted and found the commit in which their usage was
removed, which I have added in either the error message or a comment.

I've also made *some* of the version checks into static asserts for when
we update the minimum supported protocol version.

In the end this is not a lot of code we are deleting, but it's code that
we will never have to support into the future when we build a protocol
bridge, which is why I did it. It is not in the support baseline.

Change-Id: Iea3c80795c75ea74f328cf7ede7cbedf8c41926b

1 files changed, 4 insertions, 0 deletions

diff --git a/src/libstore/remote-store.cc b/src/libstore/remote-store.cc
index 575078289..b2f8a285d 100644
--- a/src/libstore/remote-store.cc
+++ b/src/libstore/remote-store.cc
@@ -307,6 +307,7 @@ StorePathSet RemoteStore::queryDerivationOutputs(const StorePath & path)
     if (GET_PROTOCOL_MINOR(getProtocol()) >= 22) {
         return Store::queryDerivationOutputs(path);
     }
+    REMOVE_AFTER_DROPPING_PROTO_MINOR(21);
     auto conn(getConnection());
     conn->to << WorkerProto::Op::QueryDerivationOutputs << printStorePath(path);
     conn.processStderr();
@@ -336,6 +337,7 @@ std::map<std::string, std::optional<StorePath>> RemoteStore::queryPartialDerivat
             return outputs;
         }
     } else {
+        REMOVE_AFTER_DROPPING_PROTO_MINOR(21);
         auto & evalStore = evalStore_ ? *evalStore_ : *this;
         // Fallback for old daemon versions.
         // For floating-CA derivations (and their co-dependencies) this is an
@@ -530,6 +532,7 @@ void RemoteStore::registerDrvOutput(const Realisation & info)
     auto conn(getConnection());
     conn->to << WorkerProto::Op::RegisterDrvOutput;
     if (GET_PROTOCOL_MINOR(conn->daemonVersion) < 31) {
+        REMOVE_AFTER_DROPPING_PROTO_MINOR(30);
         conn->to << info.id.to_string();
         conn->to << std::string(info.outPath.to_string());
     } else {
@@ -617,6 +620,7 @@ std::vector<KeyedBuildResult> RemoteStore::buildPathsWithResults(
         conn.processStderr();
         return WorkerProto::Serialise<std::vector<KeyedBuildResult>>::read(*this, *conn);
     } else {
+        REMOVE_AFTER_DROPPING_PROTO_MINOR(33);
         // Avoid deadlock.
         conn_.reset();