cayley/writer/single.go
kortschak 9e378302f5 Ensure callers get errors when they happen
Previously we silently dropped portions or all of a block when a
duplicate quad is found. We still fail now, but we tell someone.

Fixes #201.
2015-01-26 14:56:10 +10:30

75 lines
1.8 KiB
Go

// Copyright 2014 The Cayley Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package writer
import (
"time"
"github.com/google/cayley/graph"
"github.com/google/cayley/quad"
)
func init() {
graph.RegisterWriter("single", NewSingleReplication)
}
type Single struct {
currentID graph.PrimaryKey
qs graph.QuadStore
}
func NewSingleReplication(qs graph.QuadStore, opts graph.Options) (graph.QuadWriter, error) {
return &Single{currentID: qs.Horizon(), qs: qs}, nil
}
func (s *Single) AddQuad(q quad.Quad) error {
deltas := make([]graph.Delta, 1)
deltas[0] = graph.Delta{
ID: s.currentID.Next(),
Quad: q,
Action: graph.Add,
Timestamp: time.Now(),
}
return s.qs.ApplyDeltas(deltas)
}
func (s *Single) AddQuadSet(set []quad.Quad) error {
deltas := make([]graph.Delta, len(set))
for i, q := range set {
deltas[i] = graph.Delta{
ID: s.currentID.Next(),
Quad: q,
Action: graph.Add,
Timestamp: time.Now(),
}
}
return s.qs.ApplyDeltas(deltas)
}
func (s *Single) RemoveQuad(q quad.Quad) error {
deltas := make([]graph.Delta, 1)
deltas[0] = graph.Delta{
ID: s.currentID.Next(),
Quad: q,
Action: graph.Delete,
Timestamp: time.Now(),
}
return s.qs.ApplyDeltas(deltas)
}
func (s *Single) Close() error {
// Nothing to clean up locally.
return nil
}