refactor(unified-storage): make datasyncer configurable (#97832)

pkg/services/apiserver/builder/helper.go

@@ -186,12 +186,18 @@ func InstallAPIs(
 			// when missing this will default to mode zero (legacy only)
 			var mode = grafanarest.DualWriterMode(0)
 
-			var dualWriterPeriodicDataSyncJobEnabled bool
+			var (
+				dualWriterPeriodicDataSyncJobEnabled bool
+				dataSyncerInterval                   = time.Hour
+				dataSyncerRecordsLimit               = 1000
+			)
 
 			resourceConfig, resourceExists := storageOpts.UnifiedStorageConfig[key]
 			if resourceExists {
 				mode = resourceConfig.DualWriterMode
 				dualWriterPeriodicDataSyncJobEnabled = resourceConfig.DualWriterPeriodicDataSyncJobEnabled
+				dataSyncerInterval = resourceConfig.DataSyncerInterval
+				dataSyncerRecordsLimit = resourceConfig.DataSyncerRecordsLimit
 			}
 
 			// Force using storage only -- regardless of internal synchronization state
@@ -205,7 +211,21 @@ func InstallAPIs(
 			// Moving from one version to the next can only happen after the previous step has
 			// successfully synchronized.
 			requestInfo := getRequestInfo(gr, namespaceMapper)
-			currentMode, err := grafanarest.SetDualWritingMode(ctx, kvStore, legacy, storage, key, mode, reg, serverLock, requestInfo)
+
+			syncerCfg := &grafanarest.SyncerConfig{
+				Kind:                   key,
+				RequestInfo:            requestInfo,
+				Mode:                   mode,
+				LegacyStorage:          legacy,
+				Storage:                storage,
+				ServerLockService:      serverLock,
+				DataSyncerInterval:     dataSyncerInterval,
+				DataSyncerRecordsLimit: dataSyncerRecordsLimit,
+				Reg:                    reg,
+			}
+
+			// This also sets the currentMode on the syncer config.
+			currentMode, err := grafanarest.SetDualWritingMode(ctx, kvStore, syncerCfg)
 			if err != nil {
 				return nil, err
 			}
@@ -216,9 +236,12 @@ func InstallAPIs(
 				return storage, nil
 			default:
 			}
-
 			if dualWriterPeriodicDataSyncJobEnabled {
-				grafanarest.StartPeriodicDataSyncer(ctx, currentMode, legacy, storage, key, reg, serverLock, requestInfo)
+				// The mode might have changed in SetDualWritingMode, so apply current mode first.
+				syncerCfg.Mode = currentMode
+				if err := grafanarest.StartPeriodicDataSyncer(ctx, syncerCfg); err != nil {
+					return nil, err
+				}
 			}
 
 			// when unable to use

pkg/services/apiserver/options/storage.go

@@ -4,11 +4,12 @@ import (
 	"fmt"
 	"net"
 
-	"github.com/grafana/grafana/pkg/services/featuremgmt"
-	"github.com/grafana/grafana/pkg/setting"
 	"github.com/spf13/pflag"
 	genericapiserver "k8s.io/apiserver/pkg/server"
 	"k8s.io/apiserver/pkg/server/options"
+
+	"github.com/grafana/grafana/pkg/services/featuremgmt"
+	"github.com/grafana/grafana/pkg/setting"
 )
 
 type StorageType string
@@ -21,7 +22,8 @@ const (
 	StorageTypeUnifiedGrpc StorageType = "unified-grpc"
 )
 
-type StorageOptions struct { // The desired storage type
+type StorageOptions struct {
+	// The desired storage type
 	StorageType StorageType
 
 	// For unified-grpc, the address is required