*: fix system config for tenant

Follow-on from #76279.

Fixes #75864.

This commit adds a mechanism to combine the system config data of the tenant
with the data provided over the GossipSubscription from the system tenant.
It then plumbs a version into the zone config methods. In the mixed version
state, the tenant uses the existing override from the system tenant. After
the span config infrastructure has been activated, the tenant uses the
overrides they've set. This affects, realistically, just the GC job, and,
to a lesser extent, the optimizer.

Release note: None

pkg/ccl/backupccl/backup_test.go

@@ -1739,7 +1739,7 @@ func TestBackupRestoreControlJob(t *testing.T) {
 		if err != nil {
 			t.Fatal(err)
 		}
-		last := config.SystemTenantObjectID(v.ValueInt())
+		last := config.ObjectID(v.ValueInt())
 		zoneConfig := zonepb.DefaultZoneConfig()
 		zoneConfig.RangeMaxBytes = proto.Int64(5000)
 		config.TestingSetZoneConfig(last+1, zoneConfig)

pkg/ccl/kvccl/kvtenantccl/BUILD.bazel

@@ -56,6 +56,7 @@ go_test(
         "//pkg/config",
         "//pkg/gossip",
         "//pkg/jobs",
+        "//pkg/keys",
         "//pkg/kv/kvclient/kvtenant",
         "//pkg/kv/kvserver",
         "//pkg/kv/kvserver/kvserverbase",
@@ -86,6 +87,7 @@ go_test(
         "//pkg/util/stop",
         "//pkg/util/tracing",
         "//pkg/util/uuid",
+        "@com_github_cockroachdb_errors//:errors",
         "@com_github_cockroachdb_redact//:redact",
         "@com_github_stretchr_testify//assert",
         "@com_github_stretchr_testify//require",

pkg/ccl/kvccl/kvtenantccl/tenant_upgrade_test.go

@@ -17,24 +17,29 @@ import (
 
 	"github.com/cockroachdb/cockroach/pkg/base"
 	"github.com/cockroachdb/cockroach/pkg/clusterversion"
+	"github.com/cockroachdb/cockroach/pkg/config"
 	"github.com/cockroachdb/cockroach/pkg/jobs"
+	"github.com/cockroachdb/cockroach/pkg/keys"
 	"github.com/cockroachdb/cockroach/pkg/migration"
 	"github.com/cockroachdb/cockroach/pkg/migration/migrations"
 	"github.com/cockroachdb/cockroach/pkg/roachpb"
 	"github.com/cockroachdb/cockroach/pkg/security"
 	"github.com/cockroachdb/cockroach/pkg/server"
 	"github.com/cockroachdb/cockroach/pkg/settings/cluster"
 	"github.com/cockroachdb/cockroach/pkg/sql/sqlliveness/slinstance"
+	"github.com/cockroachdb/cockroach/pkg/testutils"
+	"github.com/cockroachdb/cockroach/pkg/testutils/serverutils"
 	"github.com/cockroachdb/cockroach/pkg/testutils/sqlutils"
 	"github.com/cockroachdb/cockroach/pkg/testutils/testcluster"
 	"github.com/cockroachdb/cockroach/pkg/util/leaktest"
 	"github.com/cockroachdb/cockroach/pkg/util/stop"
+	"github.com/cockroachdb/errors"
 	"github.com/stretchr/testify/require"
 )
 
 // TestTenantUpgrade exercises the case where a system tenant is in a
 // non-finalized version state and creates a tenant. The test ensures
-// that that newly created tenant begins in that same version.
+// that the newly created tenant begins in that same version.
 //
 // The first subtest creates the tenant in the mixed version state,
 // then upgrades the system tenant, then upgrades the secondary tenant,
@@ -358,3 +363,111 @@ func TestTenantUpgradeFailure(t *testing.T) {
 		tenantInfo.v2onMigrationStopper.Stop(ctx)
 	})
 }
+
+// TestTenantSystemConfigUpgrade ensures that the tenant GC job uses the
+// appropriate view of the GC TTL.
+func TestTenantSystemConfigUpgrade(t *testing.T) {
+	defer leaktest.AfterTest(t)()
+	ctx := context.Background()
+	settings := cluster.MakeTestingClusterSettingsWithVersions(
+		clusterversion.TestingBinaryVersion,
+		clusterversion.TestingBinaryMinSupportedVersion,
+		false, // initializeVersion
+	)
+	// Initialize the version to the BinaryMinSupportedVersion.
+	require.NoError(t, clusterversion.Initialize(ctx,
+		clusterversion.TestingBinaryMinSupportedVersion, &settings.SV))
+	tc := testcluster.StartTestCluster(t, 1, base.TestClusterArgs{
+		ServerArgs: base.TestServerArgs{
+			Settings: settings,
+			Knobs: base.TestingKnobs{
+				Server: &server.TestingKnobs{
+					DisableAutomaticVersionUpgrade: make(chan struct{}),
+					BinaryVersionOverride:          clusterversion.TestingBinaryMinSupportedVersion,
+				},
+			},
+		},
+	})
+	hostDB := sqlutils.MakeSQLRunner(tc.ServerConn(0))
+	hostDB.Exec(t, `SET CLUSTER SETTING kv.closed_timestamp.target_duration = '20ms'`)
+	hostDB.Exec(t, `SET CLUSTER SETTING kv.closed_timestamp.side_transport_interval = '20ms'`)
+	defer tc.Stopper().Stop(ctx)
+	connectToTenant := func(t *testing.T, addr string) (_ *gosql.DB, cleanup func()) {
+		pgURL, cleanupPGUrl := sqlutils.PGUrl(t, addr, "Tenant", url.User(security.RootUser))
+		tenantDB, err := gosql.Open("postgres", pgURL.String())
+		require.NoError(t, err)
+		return tenantDB, func() {
+			tenantDB.Close()
+			cleanupPGUrl()
+		}
+	}
+	mkTenant := func(t *testing.T, id uint64) (
+		tenant serverutils.TestTenantInterface,
+	) {
+		settings := cluster.MakeTestingClusterSettingsWithVersions(
+			clusterversion.TestingBinaryVersion,
+			clusterversion.TestingBinaryMinSupportedVersion,
+			false, // initializeVersion
+		)
+		// Initialize the version to the minimum it could be.
+		require.NoError(t, clusterversion.Initialize(ctx,
+			clusterversion.TestingBinaryMinSupportedVersion, &settings.SV))
+		tenantArgs := base.TestTenantArgs{
+			TenantID:     roachpb.MakeTenantID(id),
+			TestingKnobs: base.TestingKnobs{},
+			Settings:     settings,
+		}
+		tenant, err := tc.Server(0).StartTenant(ctx, tenantArgs)
+		require.NoError(t, err)
+		return tenant
+	}
+	const tenantID = 10
+	codec := keys.MakeSQLCodec(roachpb.MakeTenantID(tenantID))
+	tenant := mkTenant(t, tenantID)
+	tenantSQL, cleanup := connectToTenant(t, tenant.SQLAddr())
+	defer cleanup()
+	tenantDB := sqlutils.MakeSQLRunner(tenantSQL)
+	tenantDB.CheckQueryResults(t, "SHOW CLUSTER SETTING version", [][]string{{"21.2"}})
+	tenantDB.Exec(t, "CREATE TABLE foo ()")
+	fooID := sqlutils.QueryTableID(t, tenantSQL, "defaultdb", "public", "foo")
+	tenantP := tenant.SystemConfigProvider()
+	ch, _ := tenantP.RegisterSystemConfigChannel()
+
+	hostDB.Exec(t, "SET CLUSTER SETTING version = crdb_internal.node_executable_version()")
+	hostDB.Exec(t, "ALTER RANGE tenants CONFIGURE ZONE USING gc.ttlseconds = 111")
+	hostDB.Exec(t,
+		"ALTER TENANT $1 SET CLUSTER SETTING sql.zone_configs.allow_for_secondary_tenant.enabled = true;",
+		tenantID)
+	tenantDB.CheckQueryResultsRetry(
+		t, "SHOW CLUSTER SETTING sql.zone_configs.allow_for_secondary_tenant.enabled",
+		[][]string{{"true"}},
+	)
+	tenantVersion := func() clusterversion.ClusterVersion {
+		return tenant.ClusterSettings().Version.ActiveVersionOrEmpty(ctx)
+	}
+	checkConfigEqual := func(t *testing.T, exp int32) {
+		testutils.SucceedsSoon(t, func() error {
+			cfg := tenantP.GetSystemConfig()
+			if cfg == nil {
+				return errors.New("no config")
+			}
+			conf, err := tenantP.GetSystemConfig().GetZoneConfigForObject(codec, tenantVersion(), config.ObjectID(fooID))
+			if err != nil {
+				return err
+			}
+			if conf.GC.TTLSeconds != exp {
+				return errors.Errorf("got %d, expected %d", conf.GC.TTLSeconds, exp)
+			}
+			return nil
+		})
+	}
+	checkConfigEqual(t, 111)
+	<-ch
+	hostDB.Exec(t, "ALTER RANGE tenants CONFIGURE ZONE USING gc.ttlseconds = 112")
+	<-ch
+	checkConfigEqual(t, 112)
+	tenantDB.Exec(t, "SET CLUSTER SETTING version = crdb_internal.node_executable_version()")
+	tenantDB.Exec(t, "ALTER TABLE foo CONFIGURE ZONE USING gc.ttlseconds = 113")
+	<-ch
+	checkConfigEqual(t, 113)
+}

pkg/config/BUILD.bazel

@@ -15,6 +15,7 @@ go_library(
     importpath = "github.com/cockroachdb/cockroach/pkg/config",
     visibility = ["//visibility:public"],
     deps = [
+        "//pkg/clusterversion",
         "//pkg/config/zonepb",
         "//pkg/keys",
         "//pkg/roachpb",

pkg/config/keys.go

@@ -27,11 +27,11 @@ func MakeZoneKey(codec keys.SQLCodec, id descpb.ID) roachpb.Key {
 	return codec.ZoneKey(uint32(id))
 }
 
-// DecodeSystemTenantObjectID decodes the object ID for the system-tenant from
+// DecodeObjectID decodes the object ID for the system-tenant from
 // the front of key. It returns the decoded object ID, the remainder of the key,
 // and whether the result is valid (i.e., whether the key was within the system
 // tenant's structured key space).
-func DecodeSystemTenantObjectID(key roachpb.RKey) (SystemTenantObjectID, []byte, bool) {
-	rem, id, err := keys.SystemSQLCodec.DecodeTablePrefix(key.AsRawKey())
-	return SystemTenantObjectID(id), rem, err == nil
+func DecodeObjectID(codec keys.SQLCodec, key roachpb.RKey) (ObjectID, []byte, bool) {
+	rem, id, err := codec.DecodeTablePrefix(key.AsRawKey())
+	return ObjectID(id), rem, err == nil
 }

pkg/config/keys_test.go

@@ -28,7 +28,7 @@ func TestDecodeSystemTenantObjectID(t *testing.T) {
 		key       roachpb.RKey
 		keySuffix []byte
 		success   bool
-		id        config.SystemTenantObjectID
+		id        config.ObjectID
 	}{
 		// Before the structured span.
 		{roachpb.RKeyMin, nil, false, 0},
@@ -43,7 +43,7 @@ func TestDecodeSystemTenantObjectID(t *testing.T) {
 	}
 
 	for tcNum, tc := range testCases {
-		id, keySuffix, success := config.DecodeSystemTenantObjectID(tc.key)
+		id, keySuffix, success := config.DecodeObjectID(keys.SystemSQLCodec, tc.key)
 		if success != tc.success {
 			t.Errorf("#%d: expected success=%t", tcNum, tc.success)
 			continue