vschema.go

package memorytopo

import (
	"fmt"
	"path"

	"github.com/golang/protobuf/proto"
	"golang.org/x/net/context"

	"github.com/youtube/vitess/go/vt/topo"

	vschemapb "github.com/youtube/vitess/go/vt/proto/vschema"
)

/*
This file contains the vschema management code for etcdtopo.Server
*/

// SaveVSchema saves the JSON vschema into the topo.
func (s *MemoryTopo) SaveVSchema(ctx context.Context, keyspace string, vschema *vschemapb.Keyspace) error {
	p := path.Join(keyspacesPath, keyspace, topo.VSchemaFile)
	data, err := proto.Marshal(vschema)
	if err != nil {
		return err
	}

	if len(data) == 0 {
		// No vschema, remove it. So we can remove the keyspace.
		err = s.Delete(ctx, topo.GlobalCell, p, nil)
	} else {
		_, err = s.Update(ctx, topo.GlobalCell, p, data, nil)
	}
	return err
}

// GetVSchema fetches the vschema from the topo.
func (s *MemoryTopo) GetVSchema(ctx context.Context, keyspace string) (*vschemapb.Keyspace, error) {
	p := path.Join(keyspacesPath, keyspace, topo.VSchemaFile)
	data, _, err := s.Get(ctx, topo.GlobalCell, p)
	if err != nil {
		return nil, err
	}
	var vs vschemapb.Keyspace
	err = proto.Unmarshal(data, &vs)
	if err != nil {
		return nil, fmt.Errorf("bad vschema data (%v): %q", err, data)
	}
	return &vs, nil
}