Golang SystemConfig.GetValue方法代码示例

// GetZoneConfig returns the zone config for the object with 'id'.
func GetZoneConfig(cfg config.SystemConfig, id uint32) (config.ZoneConfig, bool, error) {
	// Look in the zones table.
	if zoneVal := cfg.GetValue(sqlbase.MakeZoneKey(sqlbase.ID(id))); zoneVal != nil {
		var zone config.ZoneConfig
		// We're done.
		return zone, true, zoneVal.GetProto(&zone)
	}

	// No zone config for this ID. We need to figure out if it's a database
	// or table. Lookup its descriptor.
	if descVal := cfg.GetValue(sqlbase.MakeDescMetadataKey(sqlbase.ID(id))); descVal != nil {
		// Determine whether this is a database or table.
		var desc sqlbase.Descriptor
		if err := descVal.GetProto(&desc); err != nil {
			return config.ZoneConfig{}, false, err
		}
		if tableDesc := desc.GetTable(); tableDesc != nil {
			// This is a table descriptor. Lookup its parent database zone config.
			return GetZoneConfig(cfg, uint32(tableDesc.ParentID))
		}
	}

	// Retrieve the default zone config, but only as long as that wasn't the ID
	// we were trying to retrieve (avoid infinite recursion).
	if id != keys.RootNamespaceID {
		return GetZoneConfig(cfg, keys.RootNamespaceID)
	}

	// No descriptor or not a table.
	return config.ZoneConfig{}, false, nil
}

// GetZoneConfig returns the zone config for the object with 'id'.
func GetZoneConfig(cfg config.SystemConfig, id uint32) (*config.ZoneConfig, error) {
	// Look in the zones table.
	if zoneVal := cfg.GetValue(MakeZoneKey(ID(id))); zoneVal != nil {
		zone := &config.ZoneConfig{}
		if err := zoneVal.GetProto(zone); err != nil {
			return nil, err
		}
		// We're done.
		return zone, nil
	}

	// No zone config for this ID. We need to figure out if it's a database
	// or table. Lookup its descriptor.
	if descVal := cfg.GetValue(MakeDescMetadataKey(ID(id))); descVal != nil {
		// Determine whether this is a database or table.
		desc := &Descriptor{}
		if err := descVal.GetProto(desc); err != nil {
			return nil, err
		}
		if tableDesc := desc.GetTable(); tableDesc != nil {
			// This is a table descriptor. Lookup its parent database zone config.
			return GetZoneConfig(cfg, uint32(tableDesc.ParentID))
		}
	}

	// No descriptor or not a table. This table/db could have been deleted, just
	// return the default config.
	return config.DefaultZoneConfig, nil
}

// GetTableDesc returns the table descriptor for the table with 'id'.
// Returns nil if the descriptor is not present, or is present but is not a
// table.
func GetTableDesc(cfg config.SystemConfig, id sqlbase.ID) (*sqlbase.TableDescriptor, error) {
	if descVal := cfg.GetValue(sqlbase.MakeDescMetadataKey(id)); descVal != nil {
		desc := &sqlbase.Descriptor{}
		if err := descVal.GetProto(desc); err != nil {
			return nil, err
		}
		return desc.GetTable(), nil
	}
	return nil, nil
}

func isDeleted(tableID sqlbase.ID, cfg config.SystemConfig) bool {
	descKey := sqlbase.MakeDescMetadataKey(tableID)
	val := cfg.GetValue(descKey)
	if val == nil {
		return false
	}
	var descriptor sqlbase.Descriptor
	if err := val.GetProto(&descriptor); err != nil {
		panic("unable to unmarshal table descriptor")
	}
	table := descriptor.GetTable()
	return table.Deleted()
}

func expectDescriptor(systemConfig config.SystemConfig, idKey roachpb.Key, desc *Descriptor) error {
	descValue := systemConfig.GetValue(idKey)
	if descValue == nil {
		return errStaleMetadata
	}
	var cachedDesc Descriptor
	if err := descValue.GetProto(&cachedDesc); err != nil {
		return err
	}
	if !proto.Equal(&cachedDesc, desc) {
		return errStaleMetadata
	}
	return nil
}

func expectDescriptorID(systemConfig config.SystemConfig, idKey roachpb.Key, id ID) error {
	idValue := systemConfig.GetValue(idKey)
	if idValue == nil {
		return errStaleMetadata
	}
	cachedID, err := idValue.GetInt()
	if err != nil {
		return err
	}
	if ID(cachedID) != id {
		return errStaleMetadata
	}
	return nil
}

func waitForConfigChange(t *testing.T, s *server.TestServer) (*config.SystemConfig, error) {
	var foundDesc sql.DatabaseDescriptor
	var cfg *config.SystemConfig
	return cfg, util.IsTrueWithin(func() bool {
		if cfg = s.Gossip().GetSystemConfig(); cfg != nil {
			if val := cfg.GetValue(configDescKey); val != nil {
				if err := val.GetProto(&foundDesc); err != nil {
					t.Fatal(err)
				}
				return foundDesc.ID == configID
			}
		}

		return false
	}, 10*time.Second)
}

func TestGet(t *testing.T) {
	defer leaktest.AfterTest(t)

	emptyKeys := []proto.KeyValue{}
	someKeys := []proto.KeyValue{
		plainKV("a", "vala"),
		plainKV("c", "valc"),
		plainKV("d", "vald"),
	}

	testCases := []struct {
		values []proto.KeyValue
		key    string
		found  bool
		value  string
	}{
		{emptyKeys, "a", false, ""},
		{emptyKeys, "b", false, ""},
		{emptyKeys, "c", false, ""},
		{emptyKeys, "d", false, ""},
		{emptyKeys, "e", false, ""},

		{someKeys, "", false, ""},
		{someKeys, "b", false, ""},
		{someKeys, "e", false, ""},
		{someKeys, "a0", false, ""},

		{someKeys, "a", true, "vala"},
		{someKeys, "c", true, "valc"},
		{someKeys, "d", true, "vald"},
	}

	cfg := config.SystemConfig{}
	for tcNum, tc := range testCases {
		cfg.Values = tc.values
		val, found := cfg.GetValue([]byte(tc.key))
		if found != tc.found {
			t.Errorf("#%d: expected found=%t", tcNum, tc.found)
			continue
		}
		if string(val) != tc.value {
			t.Errorf("#%d: expected value=%s, found %s", tcNum, tc.value, string(val))
		}
	}
}

// isRenamed tests if a descriptor is updated by gossip to the specified name
// and version.
func isRenamed(
	tableID sqlbase.ID,
	expectedName string,
	expectedVersion sqlbase.DescriptorVersion,
	cfg config.SystemConfig,
) bool {
	descKey := sqlbase.MakeDescMetadataKey(tableID)
	val := cfg.GetValue(descKey)
	if val == nil {
		return false
	}
	var descriptor sqlbase.Descriptor
	if err := val.GetProto(&descriptor); err != nil {
		panic("unable to unmarshal table descriptor")
	}
	table := descriptor.GetTable()
	return table.Name == expectedName && table.Version == expectedVersion
}

func TestGet(t *testing.T) {
	defer leaktest.AfterTest(t)

	emptyKeys := []roachpb.KeyValue{}
	someKeys := []roachpb.KeyValue{
		plainKV("a", "vala"),
		plainKV("c", "valc"),
		plainKV("d", "vald"),
	}

	aVal := roachpb.MakeValueFromString("vala")
	bVal := roachpb.MakeValueFromString("valc")
	cVal := roachpb.MakeValueFromString("vald")

	testCases := []struct {
		values []roachpb.KeyValue
		key    string
		value  *roachpb.Value
	}{
		{emptyKeys, "a", nil},
		{emptyKeys, "b", nil},
		{emptyKeys, "c", nil},
		{emptyKeys, "d", nil},
		{emptyKeys, "e", nil},

		{someKeys, "", nil},
		{someKeys, "b", nil},
		{someKeys, "e", nil},
		{someKeys, "a0", nil},

		{someKeys, "a", &aVal},
		{someKeys, "c", &bVal},
		{someKeys, "d", &cVal},
	}

	cfg := config.SystemConfig{}
	for tcNum, tc := range testCases {
		cfg.Values = tc.values
		if val := cfg.GetValue([]byte(tc.key)); !proto.Equal(val, tc.value) {
			t.Errorf("#%d: expected=%s, found=%s", tcNum, tc.value, val)
		}
	}
}

func waitForConfigChange(t *testing.T, s *testServer) *config.SystemConfig {
	var foundDesc sql.Descriptor
	var cfg *config.SystemConfig
	util.SucceedsSoon(t, func() error {
		if cfg = s.Gossip().GetSystemConfig(); cfg != nil {
			if val := cfg.GetValue(configDescKey); val != nil {
				if err := val.GetProto(&foundDesc); err != nil {
					t.Fatal(err)
				}
				if id := foundDesc.GetDatabase().GetID(); id != configID {
					return util.Errorf("expected database id %d; got %d", configID, id)
				}
				return nil
			}
		}
		return util.Errorf("got nil system config")
	})
	return cfg
}

// GetZoneConfig returns the zone config for the object with 'id'.
func GetZoneConfig(cfg *config.SystemConfig, id uint32) (*config.ZoneConfig, error) {
	// Look in the zones table.
	if val, ok := cfg.GetValue(MakeZoneKey(ID(id))); ok {
		zone := &config.ZoneConfig{}
		if err := proto.Unmarshal(val, zone); err != nil {
			return nil, err
		}
		// We're done.
		return zone, nil
	}

	// No zone config for this ID. We need to figure out if it's a database
	// or table. Lookup its descriptor.
	rawDesc, ok := cfg.GetValue(MakeDescMetadataKey(ID(id)))
	if !ok {
		// No descriptor. This table/db could have been deleted,
		// just return the default config.
		return config.DefaultZoneConfig, nil
	}

	// Determine whether this is a database or table.
	// TODO(marc): we need a better way of doing this. Options include:
	// - add a type field on the descriptor table
	// - separate descriptor tables for databases and tables
	// - prebuild list of databases and tables in the system config
	var dbDesc DatabaseDescriptor
	if err := proto.Unmarshal(rawDesc, &dbDesc); err == nil {
		// parses as a database: return default config.
		return config.DefaultZoneConfig, nil
	}

	var tableDesc TableDescriptor
	if err := proto.Unmarshal(rawDesc, &tableDesc); err != nil {
		// does not parse as a table either: this means an entry in the
		// descriptor table we're not familiar with.
		return nil, util.Errorf("descriptor for object ID %d is not a table or database", id)
	}

	// This is a table descriptor. Lookup its parent database zone config.
	return GetZoneConfig(cfg, uint32(tableDesc.ParentID))
}

func expectDeleted(systemConfig config.SystemConfig, key roachpb.Key) error {
	if systemConfig.GetValue(key) != nil {
		return errStaleMetadata
	}
	return nil
}