first swing at mongo indexing (iterator todo)

This commit is contained in:
Barak Michener 2014-08-10 19:35:26 -04:00
parent 8821c1968d
commit ff148f58f8
2 changed files with 117 additions and 153 deletions

View file

@ -18,7 +18,6 @@ import (
"crypto/sha1"
"encoding/hex"
"hash"
"io"
"gopkg.in/mgo.v2"
"gopkg.in/mgo.v2/bson"
@ -33,9 +32,6 @@ func init() {
graph.RegisterTripleStore("mongo", true, newTripleStore, createNewMongoGraph)
}
// Guarantee we satisfy graph.Bulkloader.
var _ graph.BulkLoader = (*TripleStore)(nil)
const DefaultDBName = "cayley"
type TripleStore struct {
@ -63,13 +59,21 @@ func createNewMongoGraph(addr string, options graph.Options) error {
Background: true,
Sparse: true,
}
db.C("triples").EnsureIndex(indexOpts)
db.C("quads").EnsureIndex(indexOpts)
indexOpts.Key = []string{"Pred"}
db.C("triples").EnsureIndex(indexOpts)
db.C("quads").EnsureIndex(indexOpts)
indexOpts.Key = []string{"Obj"}
db.C("triples").EnsureIndex(indexOpts)
db.C("quads").EnsureIndex(indexOpts)
indexOpts.Key = []string{"Label"}
db.C("triples").EnsureIndex(indexOpts)
db.C("quads").EnsureIndex(indexOpts)
logOpts := mgo.Index{
Key: []string{"LogID"},
Unique: true,
DropDups: false,
Background: true,
Sparse: true,
}
db.C("log").EnsureIndex(logOpts)
return nil
}
@ -113,114 +117,121 @@ type MongoNode struct {
Size int "Size"
}
func (qs *TripleStore) updateNodeBy(node_name string, inc int) {
var size MongoNode
node := qs.ValueOf(node_name)
err := qs.db.C("nodes").FindId(node).One(&size)
if err != nil {
if err.Error() == "not found" {
// Not found. Okay.
size.Id = node.(string)
size.Name = node_name
size.Size = inc
} else {
glog.Errorf("Error: %v", err)
return
}
} else {
size.Id = node.(string)
size.Name = node_name
size.Size += inc
}
// Removing something...
if inc < 0 {
if size.Size <= 0 {
err := qs.db.C("nodes").RemoveId(node)
if err != nil {
glog.Errorf("Error: %v while removing node %s", err, node_name)
return
}
}
}
_, err2 := qs.db.C("nodes").UpsertId(node, size)
if err2 != nil {
glog.Errorf("Error: %v", err)
}
type MongoLogEntry struct {
LogID int64 "LogID"
Action string "Action"
Key string "Key"
Timestamp int64
}
func (qs *TripleStore) writeTriple(t quad.Quad) bool {
func (qs *TripleStore) updateNodeBy(node_name string, inc int) error {
node := qs.ValueOf(node_name)
doc := bson.M{
"_id": node.(string),
"Name": node_name,
}
upsert := bson.M{
"$setOnInsert": doc,
"$inc": bson.M{
"Size": inc,
},
}
_, err := qs.db.C("nodes").UpsertId(node, upsert)
if err != nil {
glog.Errorf("Error updating node: %v", err)
}
return err
}
func (qs *TripleStore) updateTriple(t quad.Quad, id int64, proc graph.Procedure) error {
var setname string
if proc == graph.Add {
setname = "Added"
} else if proc == graph.Delete {
setname = "Deleted"
}
tripledoc := bson.M{
"_id": qs.getIdForTriple(t),
"Subject": t.Subject,
"Predicate": t.Predicate,
"Object": t.Object,
"Label": t.Label,
}
err := qs.db.C("triples").Insert(tripledoc)
upsert := bson.M{
"$setOnInsert": tripledoc,
"$push": bson.M{
setname: id,
},
}
_, err := qs.db.C("quads").UpsertId(qs.getIdForTriple(t), upsert)
if err != nil {
// Among the reasons I hate MongoDB. "Errors don't happen! Right guys?"
if err.(*mgo.LastError).Code == 11000 {
return false
}
glog.Errorf("Error: %v", err)
return false
}
return true
return err
}
func (qs *TripleStore) AddTriple(t quad.Quad) {
_ = qs.writeTriple(t)
qs.updateNodeBy(t.Subject, 1)
qs.updateNodeBy(t.Predicate, 1)
qs.updateNodeBy(t.Object, 1)
if t.Label != "" {
qs.updateNodeBy(t.Label, 1)
func (qs *TripleStore) updateLog(d *graph.Delta) error {
var action string
if d.Action == graph.Add {
action = "Add"
} else {
action = "Delete"
}
entry := MongoLogEntry{
LogID: d.ID,
Action: action,
Key: qs.getIdForTriple(d.Quad),
Timestamp: d.Timestamp.UnixNano(),
}
err := qs.db.C("log").Insert(entry)
if err != nil {
glog.Errorf("Error updating log: %v", err)
}
return err
}
func (qs *TripleStore) AddTripleSet(in []quad.Quad) {
func (qs *TripleStore) ApplyDeltas(in []*graph.Delta) error {
qs.session.SetSafe(nil)
ids := make(map[string]int)
for _, t := range in {
wrote := qs.writeTriple(t)
if wrote {
ids[t.Subject]++
ids[t.Object]++
ids[t.Predicate]++
if t.Label != "" {
ids[t.Label]++
}
for _, d := range in {
err := qs.updateLog(d)
if err != nil {
return err
}
}
for _, d := range in {
err := qs.updateTriple(d.Quad, d.ID, d.Action)
if err != nil {
return err
}
var countdelta int
if d.Action == graph.Add {
countdelta = 1
} else {
countdelta = -1
}
ids[d.Quad.Subject] += countdelta
ids[d.Quad.Object] += countdelta
ids[d.Quad.Predicate] += countdelta
if d.Quad.Label != "" {
ids[d.Quad.Label] += countdelta
}
}
for k, v := range ids {
qs.updateNodeBy(k, v)
err := qs.updateNodeBy(k, v)
if err != nil {
return err
}
}
qs.session.SetSafe(&mgo.Safe{})
}
func (qs *TripleStore) RemoveTriple(t quad.Quad) {
err := qs.db.C("triples").RemoveId(qs.getIdForTriple(t))
if err == mgo.ErrNotFound {
return
} else if err != nil {
glog.Errorf("Error: %v while removing triple %v", err, t)
return
}
qs.updateNodeBy(t.Subject, -1)
qs.updateNodeBy(t.Predicate, -1)
qs.updateNodeBy(t.Object, -1)
if t.Label != "" {
qs.updateNodeBy(t.Label, -1)
}
return nil
}
func (qs *TripleStore) Quad(val graph.Value) quad.Quad {
var bsonDoc bson.M
err := qs.db.C("triples").FindId(val.(string)).One(&bsonDoc)
err := qs.db.C("quads").FindId(val.(string)).One(&bsonDoc)
if err != nil {
glog.Errorf("Error: Couldn't retrieve triple %s %v", val, err)
glog.Errorf("Error: Couldn't retrieve quad %s %v", val, err)
}
return quad.Quad{
bsonDoc["Subject"].(string),
@ -231,7 +242,7 @@ func (qs *TripleStore) Quad(val graph.Value) quad.Quad {
}
func (qs *TripleStore) TripleIterator(d quad.Direction, val graph.Value) graph.Iterator {
return NewIterator(qs, "triples", d, val)
return NewIterator(qs, "quads", d, val)
}
func (qs *TripleStore) NodesAllIterator() graph.Iterator {
@ -239,7 +250,7 @@ func (qs *TripleStore) NodesAllIterator() graph.Iterator {
}
func (qs *TripleStore) TriplesAllIterator() graph.Iterator {
return NewAllIterator(qs, "triples")
return NewAllIterator(qs, "quads")
}
func (qs *TripleStore) ValueOf(s string) graph.Value {
@ -261,7 +272,8 @@ func (qs *TripleStore) NameOf(v graph.Value) string {
}
func (qs *TripleStore) Size() int64 {
count, err := qs.db.C("triples").Count()
// TODO(barakmich): Make size real; store it in the log, and retrieve it.
count, err := qs.db.C("quads").Count()
if err != nil {
glog.Errorf("Error: %v", err)
return 0
@ -269,6 +281,15 @@ func (qs *TripleStore) Size() int64 {
return int64(count)
}
func (qs *TripleStore) Horizon() int64 {
var log MongoLogEntry
err := qs.db.C("log").Find(nil).Sort("-LogID").One(&log)
if err != nil {
glog.Errorf("Could not get Horizon from Mongo: %v", err)
}
return log.LogID
}
func compareStrings(a, b graph.Value) bool {
return a.(string) == b.(string)
}
@ -298,61 +319,4 @@ func (qs *TripleStore) TripleDirection(in graph.Value, d quad.Direction) graph.V
return val
}
func (qs *TripleStore) BulkLoad(dec quad.Unmarshaler) error {
if qs.Size() != 0 {
return graph.ErrCannotBulkLoad
}
qs.session.SetSafe(nil)
for {
q, err := dec.Unmarshal()
if err != nil {
if err != io.EOF {
return err
}
break
}
qs.writeTriple(q)
}
outputTo := bson.M{"replace": "nodes", "sharded": true}
glog.Infoln("Mapreducing")
job := mgo.MapReduce{
Map: `function() {
var len = this["_id"].length
var s_key = this["_id"].slice(0, len / 4)
var p_key = this["_id"].slice(len / 4, 2 * len / 4)
var o_key = this["_id"].slice(2 * len / 4, 3 * len / 4)
var c_key = this["_id"].slice(3 * len / 4)
emit(s_key, {"_id": s_key, "Name" : this.Subject, "Size" : 1})
emit(p_key, {"_id": p_key, "Name" : this.Predicate, "Size" : 1})
emit(o_key, {"_id": o_key, "Name" : this.Object, "Size" : 1})
if (this.Label != "") {
emit(c_key, {"_id": c_key, "Name" : this.Label, "Size" : 1})
}
}
`,
Reduce: `
function(key, value_list) {
out = {"_id": key, "Name": value_list[0].Name}
count = 0
for (var i = 0; i < value_list.length; i++) {
count = count + value_list[i].Size
}
out["Size"] = count
return out
}
`,
Out: outputTo,
}
qs.db.C("triples").Find(nil).MapReduce(&job, nil)
glog.Infoln("Fixing")
qs.db.Run(bson.D{{"eval", `function() { db.nodes.find().forEach(function (result) {
db.nodes.update({"_id": result._id}, result.value)
}) }`}, {"args", bson.D{}}}, nil)
qs.session.SetSafe(&mgo.Safe{})
return nil
}
// TODO(barakmich): Rewrite bulk loader. For now, iterating around blocks is the way we'll go about it.

View file

@ -22,6 +22,10 @@ import (
"github.com/google/cayley/quad"
)
func init() {
graph.RegisterWriter("single", NewSingleReplication)
}
type Single struct {
nextID int64
ts graph.TripleStore
@ -79,7 +83,3 @@ func (s *Single) RemoveQuad(q quad.Quad) error {
}
return s.ts.ApplyDeltas(deltas)
}
func init() {
graph.RegisterWriter("single", NewSingleReplication)
}