Merge #148450

148450: kv,server: extract TenantUsage and TenantSpanConfig and register with DRPC server r=cthumuluru-crdb a=shubhamdhama

This is a follow-up to #145195, where we extracted `KVBatch` from the
`Internal` service. Here, we do the same with `TenantUsage` and `TenantSpanConfig`. The TL;DR is
that smaller services are easier to maintain and can be more smoothly
migrated to DRPC.

We also enable this service on the DRPC server. This is controlled by
`rpc.experimental_drpc.enabled` (off by default).

This change is part of a series and is similar to: #146926

Note: This only registers the service; the client is not updated to use the
DRPC client, so this service will not have any functional effect.

Epic: CRDB-48925
Release note: None


Co-authored-by: Shubham Dhama <[email protected]>

Author: craig[bot]

pkg/kv/kvpb/api.proto

@@ -3684,6 +3684,34 @@ service TenantService {
   rpc GetRangeDescriptors(GetRangeDescriptorsRequest) returns (stream GetRangeDescriptorsResponse) {}
 }
 
+// TenantUsage provides RPCs for secondary tenants to report resource
+// consumption and get Request Units available.
+service TenantUsage {
+  // TokenBucket is used by tenants to obtain Request Units and report
+  // consumption.
+  rpc TokenBucket (TokenBucketRequest) returns (TokenBucketResponse) {}
+}
+
+// TenantSpanConfig provides RPCs for secondary tenants to operate on span
+// configs, such as reading and updating them.
+service TenantSpanConfig {
+  // GetSpanConfigs is used to fetch the span configurations over a given
+  // keyspan.
+  rpc GetSpanConfigs(GetSpanConfigsRequest) returns (GetSpanConfigsResponse) {}
+
+  // GetAllSystemSpanConfigsThatApply is used to fetch all system span
+  // configurations that apply over a tenant's ranges.
+  rpc GetAllSystemSpanConfigsThatApply(GetAllSystemSpanConfigsThatApplyRequest) returns (GetAllSystemSpanConfigsThatApplyResponse) {}
+
+  // UpdateSpanConfigs is used to update the span configurations over given
+  // keyspans.
+  rpc UpdateSpanConfigs(UpdateSpanConfigsRequest) returns (UpdateSpanConfigsResponse) {}
+
+  // SpanConfigConformance is used to determine whether ranges backing the given
+  // keyspans conform to span configs that apply over them.
+  rpc SpanConfigConformance(SpanConfigConformanceRequest) returns (SpanConfigConformanceResponse) {}
+}
+
 // Batch and RangeFeed service implemented by nodes for KV API requests.
 service Internal {
   rpc Batch (BatchRequest) returns (BatchResponse) {}

pkg/server/server.go

@@ -989,6 +989,12 @@ func NewServer(cfg Config, stopper *stop.Stopper) (serverctl.ServerStartupInterf
 	if err := kvpb.DRPCRegisterTenantService(drpcServer, node.AsDRPCTenantServiceServer()); err != nil {
 		return nil, err
 	}
+	if err := kvpb.DRPCRegisterTenantUsage(drpcServer, node); err != nil {
+		return nil, err
+	}
+	if err := kvpb.DRPCRegisterTenantSpanConfig(drpcServer, node); err != nil {
+		return nil, err
+	}
 	kvserver.RegisterPerReplicaServer(grpcServer.Server, node.perReplicaServer)
 	if err := kvserver.DRPCRegisterPerReplica(drpcServer, node.perReplicaServer); err != nil {
 		return nil, err