[wip] server,roachpb: move join rpc into InternalServer

And address remaining PR comments (this commit will be squashed up).

Release note: None

pkg/ccl/kvccl/kvtenantccl/connector_test.go

@@ -39,6 +39,8 @@ var rpcRetryOpts = retry.Options{
 	MaxBackoff:     4 * time.Microsecond,
 }
 
+var _ roachpb.InternalServer = &mockServer{}
+
 type mockServer struct {
 	rangeLookupFn func(context.Context, *roachpb.RangeLookupRequest) (*roachpb.RangeLookupResponse, error)
 	gossipSubFn   func(*roachpb.GossipSubscriptionRequest, roachpb.Internal_GossipSubscriptionServer) error
@@ -64,6 +66,12 @@ func (*mockServer) RangeFeed(*roachpb.RangeFeedRequest, roachpb.Internal_RangeFe
 	panic("unimplemented")
 }
 
+func (m *mockServer) Join(
+	context.Context, *roachpb.JoinNodeRequest,
+) (*roachpb.JoinNodeResponse, error) {
+	panic("unimplemented")
+}
+
 func gossipEventForNodeDesc(desc *roachpb.NodeDescriptor) *roachpb.GossipSubscriptionEvent {
 	val, err := protoutil.Marshal(desc)
 	if err != nil {

pkg/clusterversion/cockroach_versions.go

@@ -589,6 +589,7 @@ var (
 	// this binary. If this binary is started using a store marked with an older
 	// version than binaryMinSupportedVersion, then the binary will exit with
 	// an error.
+	//
 	// We support everything after 19.1, including pre-release 19.2 versions.
 	// This is generally beneficial, but in particular it allows the
 	// version-upgrade roachtest to use a pre-release 19.2 binary before upgrading

pkg/kv/kvclient/kvcoord/send_test.go

@@ -34,6 +34,8 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
+var _ roachpb.InternalServer = Node(0)
+
 type Node time.Duration
 
 func (n Node) Batch(
@@ -61,6 +63,10 @@ func (n Node) GossipSubscription(
 	panic("unimplemented")
 }
 
+func (n Node) Join(context.Context, *roachpb.JoinNodeRequest) (*roachpb.JoinNodeResponse, error) {
+	panic("unimplemented")
+}
+
 // TestSendToOneClient verifies that Send correctly sends a request
 // to one server using the heartbeat RPC.
 func TestSendToOneClient(t *testing.T) {

pkg/kv/kvclient/kvcoord/transport_test.go

@@ -179,3 +179,9 @@ func (m *mockInternalClient) GossipSubscription(
 ) (roachpb.Internal_GossipSubscriptionClient, error) {
 	return nil, fmt.Errorf("unsupported GossipSubscripion call")
 }
+
+func (m *mockInternalClient) Join(
+	context.Context, *roachpb.JoinNodeRequest, ...grpc.CallOption,
+) (*roachpb.JoinNodeResponse, error) {
+	return nil, fmt.Errorf("unsupported Join call")
+}

pkg/kv/kvserver/replica_gossip.go

@@ -287,7 +287,7 @@ func (r *Replica) maybeGossipFirstRange(ctx context.Context) *roachpb.Error {
 	// Gossip the cluster ID from all replicas of the first range; there
 	// is no expiration on the cluster ID.
 	if log.V(1) {
-		log.Infof(ctx, "gossiping cluster id %q from store %d, r%d", r.store.ClusterID(),
+		log.Infof(ctx, "gossiping cluster ID %q from store %d, r%d", r.store.ClusterID(),
 			r.store.StoreID(), r.RangeID)
 	}
 	if err := r.store.Gossip().AddClusterID(r.store.ClusterID()); err != nil {

pkg/roachpb/api.proto

@@ -2196,10 +2196,37 @@ message GossipSubscriptionEvent {
   Error error = 4;
 }
 
+// JoinNodeRequest is used to specify to the server node what the client's
+// MinimumSupportedVersion is. If it's not compatible with the rest of the
+// cluster, the join attempt is refused.
+message JoinNodeRequest {
+  // TODO(irfansharif): Actually make use of this min supported version.
+  roachpb.Version min_supported_version = 1;
+}
+
+// JoinNodeResponse informs the joining node what the cluster id is and what
+// node id was allocated to it.
+//
+// TODO(irfansharif): Think about the semantics for how store IDs get allocated.
+// When letting a node join, we could return back at most (least?) one store ID,
+// and entrust the node itself to allocate IDs for the remaining stores.
+//
+// TODO(irfansharif): We should use this RPC to tell us the right cluster
+// version to use (instead of using the minimum possible version and relying on
+// gossip to bump to for us).
+message JoinNodeResponse {
+  bytes cluster_id = 1 [(gogoproto.customname) = "ClusterID"];
+  int32 node_id = 2 [(gogoproto.customname) = "NodeID"];
+}
+
 // Batch and RangeFeed service implemeted by nodes for KV API requests.
 service Internal {
   rpc Batch              (BatchRequest)              returns (BatchResponse)                  {}
   rpc RangeLookup        (RangeLookupRequest)        returns (RangeLookupResponse)            {}
   rpc RangeFeed          (RangeFeedRequest)          returns (stream RangeFeedEvent)          {}
   rpc GossipSubscription (GossipSubscriptionRequest) returns (stream GossipSubscriptionEvent) {}
+
+  // Join a bootstrapped cluster. If the target node is itself not part of a
+  // bootstrapped cluster, an appropriate error is returned.
+  rpc Join(JoinNodeRequest) returns (JoinNodeResponse) { }
 }

pkg/rpc/context.go

@@ -504,6 +504,13 @@ func (a internalClientAdapter) RangeLookup(
 	return a.InternalServer.RangeLookup(ctx, rl)
 }
 
+// Join implements the roachpb.InternalClient interface.
+func (a internalClientAdapter) Join(
+	ctx context.Context, req *roachpb.JoinNodeRequest, _ ...grpc.CallOption,
+) (*roachpb.JoinNodeResponse, error) {
+	return a.InternalServer.Join(ctx, req)
+}
+
 type respStreamClientAdapter struct {
 	ctx   context.Context
 	respC chan interface{}

pkg/rpc/context_test.go

@@ -162,6 +162,8 @@ func TestHeartbeatCB(t *testing.T) {
 	})
 }
 
+var _ roachpb.InternalServer = &internalServer{}
+
 type internalServer struct{}
 
 func (*internalServer) Batch(
@@ -188,6 +190,12 @@ func (*internalServer) GossipSubscription(
 	panic("unimplemented")
 }
 
+func (*internalServer) Join(
+	context.Context, *roachpb.JoinNodeRequest,
+) (*roachpb.JoinNodeResponse, error) {
+	panic("unimplemented")
+}
+
 // TestInternalServerAddress verifies that RPCContext uses AdvertiseAddr, not Addr, to
 // determine whether to apply the local server optimization.
 //

pkg/server/grpc_server.go

@@ -67,7 +67,6 @@ var rpcsAllowedWhileBootstrapping = map[string]struct{}{
 	"/cockroach.rpc.Heartbeat/Ping":             {},
 	"/cockroach.gossip.Gossip/Gossip":           {},
 	"/cockroach.server.serverpb.Init/Bootstrap": {},
-	"/cockroach.server.serverpb.Init/Join":      {},
 	"/cockroach.server.serverpb.Admin/Health":   {},
 }