Destutter filenames

graph/mongo/iterator.go

@@ -0,0 +1,181 @@
+// 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 mongo
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/barakmich/glog"
+	"labix.org/v2/mgo"
+	"labix.org/v2/mgo/bson"
+
+	"github.com/google/cayley/graph"
+)
+
+type MongoIterator struct {
+	graph.BaseIterator
+	ts         *MongoTripleStore
+	dir        string
+	iter       *mgo.Iter
+	hash       string
+	name       string
+	size       int64
+	isAll      bool
+	constraint bson.M
+	collection string
+}
+
+func NewMongoIterator(ts *MongoTripleStore, collection string, dir string, val graph.TSVal) *MongoIterator {
+	var m MongoIterator
+	graph.BaseIteratorInit(&m.BaseIterator)
+
+	m.name = ts.GetNameFor(val)
+	m.collection = collection
+	switch dir {
+
+	case "s":
+		m.constraint = bson.M{"Sub": m.name}
+	case "p":
+		m.constraint = bson.M{"Pred": m.name}
+	case "o":
+		m.constraint = bson.M{"Obj": m.name}
+	case "c":
+		m.constraint = bson.M{"Provenance": m.name}
+	}
+
+	m.ts = ts
+	m.dir = dir
+	m.iter = ts.db.C(collection).Find(m.constraint).Iter()
+	size, err := ts.db.C(collection).Find(m.constraint).Count()
+	if err != nil {
+		glog.Errorln("Trouble getting size for iterator! ", err)
+		return nil
+	}
+	m.size = int64(size)
+	m.hash = val.(string)
+	m.isAll = false
+	return &m
+}
+
+func NewMongoAllIterator(ts *MongoTripleStore, collection string) *MongoIterator {
+	var m MongoIterator
+	m.ts = ts
+	m.dir = "all"
+	m.constraint = nil
+	m.collection = collection
+	m.iter = ts.db.C(collection).Find(nil).Iter()
+	size, err := ts.db.C(collection).Count()
+	if err != nil {
+		glog.Errorln("Trouble getting size for iterator! ", err)
+		return nil
+	}
+	m.size = int64(size)
+	m.hash = ""
+	m.isAll = true
+	return &m
+}
+
+func (m *MongoIterator) Reset() {
+	m.iter.Close()
+	m.iter = m.ts.db.C(m.collection).Find(m.constraint).Iter()
+
+}
+
+func (m *MongoIterator) Close() {
+	m.iter.Close()
+}
+
+func (m *MongoIterator) Clone() graph.Iterator {
+	var newM graph.Iterator
+	if m.isAll {
+		newM = NewMongoAllIterator(m.ts, m.collection)
+	} else {
+		newM = NewMongoIterator(m.ts, m.collection, m.dir, m.hash)
+	}
+	newM.CopyTagsFrom(m)
+	return newM
+}
+
+func (m *MongoIterator) Next() (graph.TSVal, bool) {
+	var result struct {
+		Id string "_id"
+		//Sub string "Sub"
+		//Pred string "Pred"
+		//Obj string "Obj"
+	}
+	found := m.iter.Next(&result)
+	if !found {
+		err := m.iter.Err()
+		if err != nil {
+			glog.Errorln("Error Nexting MongoIterator: ", err)
+		}
+		return nil, false
+	}
+	m.Last = result.Id
+	return result.Id, true
+}
+
+func (m *MongoIterator) Check(v graph.TSVal) bool {
+	graph.CheckLogIn(m, v)
+	if m.isAll {
+		m.Last = v
+		return graph.CheckLogOut(m, v, true)
+	}
+	var offset int
+	switch m.dir {
+	case "s":
+		offset = 0
+	case "p":
+		offset = (m.ts.hasher.Size() * 2)
+	case "o":
+		offset = (m.ts.hasher.Size() * 2) * 2
+	case "c":
+		offset = (m.ts.hasher.Size() * 2) * 3
+	}
+	val := v.(string)[offset : m.ts.hasher.Size()*2+offset]
+	if val == m.hash {
+		m.Last = v
+		return graph.CheckLogOut(m, v, true)
+	}
+	return graph.CheckLogOut(m, v, false)
+}
+
+func (m *MongoIterator) Size() (int64, bool) {
+	return m.size, true
+}
+
+func (m *MongoIterator) Type() string {
+	if m.isAll {
+		return "all"
+	}
+	return "mongo"
+}
+func (m *MongoIterator) Sorted() bool                     { return true }
+func (m *MongoIterator) Optimize() (graph.Iterator, bool) { return m, false }
+
+func (m *MongoIterator) DebugString(indent int) string {
+	size, _ := m.Size()
+	return fmt.Sprintf("%s(%s size:%d %s %s)", strings.Repeat(" ", indent), m.Type(), size, m.hash, m.name)
+}
+
+func (m *MongoIterator) GetStats() *graph.IteratorStats {
+	size, _ := m.Size()
+	return &graph.IteratorStats{
+		CheckCost: 1,
+		NextCost:  5,
+		Size:      size,
+	}
+}