func hasMorphism(via interface{}, nodes ...string) morphism {
return morphism{
Name: "has",
Reversal: func() morphism { return hasMorphism(via, nodes...) },
Apply: func(qs graph.QuadStore, it graph.Iterator) graph.Iterator {
var sub graph.Iterator
if len(nodes) == 0 {
sub = qs.NodesAllIterator()
} else {
fixed := qs.FixedIterator()
for _, n := range nodes {
fixed.Add(qs.ValueOf(n))
}
sub = fixed
}
var viaPath *Path
if via != nil {
viaPath = buildViaPath(qs, via)
} else {
viaPath = buildViaPath(qs)
}
subAnd := iterator.NewAnd(qs)
subAnd.AddSubIterator(iterator.NewLinksTo(qs, sub, quad.Object))
subAnd.AddSubIterator(iterator.NewLinksTo(qs, viaPath.BuildIterator(), quad.Predicate))
hasa := iterator.NewHasA(qs, subAnd, quad.Subject)
and := iterator.NewAnd(qs)
and.AddSubIterator(it)
and.AddSubIterator(hasa)
return and
},
}
}
func TestRemoveQuad(t *testing.T) {
qs, w, _ := makeTestStore(simpleGraph)
w.RemoveQuad(quad.Quad{
Subject: "E",
Predicate: "follows",
Object: "F",
Label: "",
})
fixed := qs.FixedIterator()
fixed.Add(qs.ValueOf("E"))
fixed2 := qs.FixedIterator()
fixed2.Add(qs.ValueOf("follows"))
innerAnd := iterator.NewAnd(qs)
innerAnd.AddSubIterator(iterator.NewLinksTo(qs, fixed, quad.Subject))
innerAnd.AddSubIterator(iterator.NewLinksTo(qs, fixed2, quad.Predicate))
hasa := iterator.NewHasA(qs, innerAnd, quad.Object)
newIt, _ := hasa.Optimize()
if graph.Next(newIt) {
t.Error("E should not have any followers.")
}
}
func TestIteratorsAndNextResultOrderA(t *testing.T) {
glog.Info("\n-----------\n")
inst, opts, err := createInstance()
defer inst.Close()
if err != nil {
t.Fatalf("failed to create instance: %v", err)
}
qs, _, _ := makeTestStore(simpleGraph, opts)
if qs.Size() != 11 {
t.Fatal("Incorrect number of quads")
}
fixed := qs.FixedIterator()
fixed.Add(qs.ValueOf("C"))
fixed2 := qs.FixedIterator()
fixed2.Add(qs.ValueOf("follows"))
all := qs.NodesAllIterator()
innerAnd := iterator.NewAnd(qs)
innerAnd.AddSubIterator(iterator.NewLinksTo(qs, fixed2, quad.Predicate))
innerAnd.AddSubIterator(iterator.NewLinksTo(qs, all, quad.Object))
hasa := iterator.NewHasA(qs, innerAnd, quad.Subject)
outerAnd := iterator.NewAnd(qs)
outerAnd.AddSubIterator(fixed)
outerAnd.AddSubIterator(hasa)
if !outerAnd.Next() {
t.Error("Expected one matching subtree")
}
val := outerAnd.Result()
if qs.NameOf(val) != "C" {
t.Errorf("Matching subtree should be %s, got %s", "barak", qs.NameOf(val))
}
var (
got []string
expect = []string{"B", "D"}
)
for {
got = append(got, qs.NameOf(all.Result()))
if !outerAnd.NextPath() {
break
}
}
sort.Strings(got)
if !reflect.DeepEqual(got, expect) {
t.Errorf("Unexpected result, got:%q expect:%q", got, expect)
}
if outerAnd.Next() {
t.Error("More than one possible top level output?")
}
}
func buildInOutPredicateIterator(obj *otto.Object, qs graph.QuadStore, base graph.Iterator, isReverse bool) graph.Iterator {
dir := quad.Subject
if isReverse {
dir = quad.Object
}
lto := iterator.NewLinksTo(qs, base, dir)
hasa := iterator.NewHasA(qs, lto, quad.Predicate)
return iterator.NewUnique(hasa)
}
func inOutIterator(viaPath *Path, it graph.Iterator, reverse bool) graph.Iterator {
in, out := quad.Subject, quad.Object
if reverse {
in, out = out, in
}
lto := iterator.NewLinksTo(viaPath.qs, it, in)
and := iterator.NewAnd(viaPath.qs)
and.AddSubIterator(iterator.NewLinksTo(viaPath.qs, viaPath.BuildIterator(), quad.Predicate))
and.AddSubIterator(lto)
return iterator.NewHasA(viaPath.qs, and, out)
}
func TestIteratorsAndNextResultOrderA(t *testing.T) {
qs, _, _ := makeTestStore(simpleGraph)
fixed := qs.FixedIterator()
fixed.Add(qs.ValueOf("C"))
fixed2 := qs.FixedIterator()
fixed2.Add(qs.ValueOf("follows"))
all := qs.NodesAllIterator()
innerAnd := iterator.NewAnd(qs)
innerAnd.AddSubIterator(iterator.NewLinksTo(qs, fixed2, quad.Predicate))
innerAnd.AddSubIterator(iterator.NewLinksTo(qs, all, quad.Object))
hasa := iterator.NewHasA(qs, innerAnd, quad.Subject)
outerAnd := iterator.NewAnd(qs)
outerAnd.AddSubIterator(fixed)
outerAnd.AddSubIterator(hasa)
if !outerAnd.Next() {
t.Error("Expected one matching subtree")
}
val := outerAnd.Result()
if qs.NameOf(val) != "C" {
t.Errorf("Matching subtree should be %s, got %s", "barak", qs.NameOf(val))
}
var (
got []string
expect = []string{"B", "D"}
)
for {
got = append(got, qs.NameOf(all.Result()))
if !outerAnd.NextPath() {
break
}
}
sort.Strings(got)
if !reflect.DeepEqual(got, expect) {
t.Errorf("Unexpected result, got:%q expect:%q", got, expect)
}
if outerAnd.Next() {
t.Error("More than one possible top level output?")
}
}
func buildInOutIterator(obj *otto.Object, qs graph.QuadStore, base graph.Iterator, isReverse bool) graph.Iterator {
argList, _ := obj.Get("_gremlin_values")
if argList.Class() != "GoArray" {
glog.Errorln("How is arglist not an array? Return nothing.", argList.Class())
return iterator.NewNull()
}
argArray := argList.Object()
lengthVal, _ := argArray.Get("length")
length, _ := lengthVal.ToInteger()
var predicateNodeIterator graph.Iterator
if length == 0 {
predicateNodeIterator = qs.NodesAllIterator()
} else {
zero, _ := argArray.Get("0")
predicateNodeIterator = buildIteratorFromValue(zero, qs)
}
if length >= 2 {
var tags []string
one, _ := argArray.Get("1")
if one.IsString() {
tags = append(tags, one.String())
} else if one.Class() == "Array" {
tags = stringsFrom(one.Object())
}
for _, tag := range tags {
predicateNodeIterator.Tagger().Add(tag)
}
}
in, out := quad.Subject, quad.Object
if isReverse {
in, out = out, in
}
lto := iterator.NewLinksTo(qs, base, in)
and := iterator.NewAnd(qs)
and.AddSubIterator(iterator.NewLinksTo(qs, predicateNodeIterator, quad.Predicate))
and.AddSubIterator(lto)
return iterator.NewHasA(qs, and, out)
}
func buildSave(qs graph.QuadStore, via interface{}, tag string, it graph.Iterator, reverse bool) graph.Iterator {
all := qs.NodesAllIterator()
all.Tagger().Add(tag)
node, allDir := quad.Subject, quad.Object
var viaPath *Path
if via != nil {
viaPath = buildViaPath(qs, via)
} else {
viaPath = buildViaPath(qs)
}
if reverse {
node, allDir = allDir, node
}
lto := iterator.NewLinksTo(qs, all, allDir)
subAnd := iterator.NewAnd(qs)
subAnd.AddSubIterator(iterator.NewLinksTo(qs, viaPath.BuildIterator(), quad.Predicate))
subAnd.AddSubIterator(lto)
hasa := iterator.NewHasA(qs, subAnd, node)
and := iterator.NewAnd(qs)
and.AddSubIterator(hasa)
and.AddSubIterator(it)
return and
}
func buildIteratorTree(tree *peg.ExpressionTree, qs graph.QuadStore) graph.Iterator {
switch tree.Name {
case "Start":
return buildIteratorTree(tree.Children[0], qs)
case "NodeIdentifier":
var out graph.Iterator
nodeID := getIdentString(tree)
if tree.Children[0].Name == "Variable" {
allIt := qs.NodesAllIterator()
allIt.Tagger().Add(nodeID)
out = allIt
} else {
n := nodeID
if tree.Children[0].Children[0].Name == "ColonIdentifier" {
n = nodeID[1:]
}
fixed := qs.FixedIterator()
fixed.Add(qs.ValueOf(n))
out = fixed
}
return out
case "PredIdentifier":
i := 0
if tree.Children[0].Name == "Reverse" {
//Taken care of below
i++
}
it := buildIteratorTree(tree.Children[i], qs)
lto := iterator.NewLinksTo(qs, it, quad.Predicate)
return lto
case "RootConstraint":
constraintCount := 0
and := iterator.NewAnd(qs)
for _, c := range tree.Children {
switch c.Name {
case "NodeIdentifier":
fallthrough
case "Constraint":
it := buildIteratorTree(c, qs)
and.AddSubIterator(it)
constraintCount++
continue
default:
continue
}
}
return and
case "Constraint":
var hasa *iterator.HasA
topLevelDir := quad.Subject
subItDir := quad.Object
subAnd := iterator.NewAnd(qs)
isOptional := false
for _, c := range tree.Children {
switch c.Name {
case "PredIdentifier":
if c.Children[0].Name == "Reverse" {
topLevelDir = quad.Object
subItDir = quad.Subject
}
it := buildIteratorTree(c, qs)
subAnd.AddSubIterator(it)
continue
case "PredicateKeyword":
switch c.Children[0].Name {
case "OptionalKeyword":
isOptional = true
}
case "NodeIdentifier":
fallthrough
case "RootConstraint":
it := buildIteratorTree(c, qs)
l := iterator.NewLinksTo(qs, it, subItDir)
subAnd.AddSubIterator(l)
continue
default:
continue
}
}
hasa = iterator.NewHasA(qs, subAnd, topLevelDir)
if isOptional {
optional := iterator.NewOptional(hasa)
return optional
}
return hasa
default:
return &iterator.Null{}
}
}
func buildIteratorTreeHelper(obj *otto.Object, qs graph.QuadStore, base graph.Iterator) graph.Iterator {
// TODO: Better error handling
var (
it graph.Iterator
subIt graph.Iterator
)
if prev, _ := obj.Get("_gremlin_prev"); !prev.IsObject() {
subIt = base
} else {
subIt = buildIteratorTreeHelper(prev.Object(), qs, base)
}
stringArgs := propertiesOf(obj, "string_args")
val, _ := obj.Get("_gremlin_type")
switch val.String() {
case "vertex":
if len(stringArgs) == 0 {
it = qs.NodesAllIterator()
} else {
fixed := qs.FixedIterator()
for _, name := range stringArgs {
fixed.Add(qs.ValueOf(name))
}
it = fixed
}
case "tag":
it = subIt
for _, tag := range stringArgs {
it.Tagger().Add(tag)
}
case "save":
all := qs.NodesAllIterator()
if len(stringArgs) > 2 || len(stringArgs) == 0 {
return iterator.NewNull()
}
if len(stringArgs) == 2 {
all.Tagger().Add(stringArgs[1])
} else {
all.Tagger().Add(stringArgs[0])
}
predFixed := qs.FixedIterator()
predFixed.Add(qs.ValueOf(stringArgs[0]))
subAnd := iterator.NewAnd(qs)
subAnd.AddSubIterator(iterator.NewLinksTo(qs, predFixed, quad.Predicate))
subAnd.AddSubIterator(iterator.NewLinksTo(qs, all, quad.Object))
hasa := iterator.NewHasA(qs, subAnd, quad.Subject)
and := iterator.NewAnd(qs)
and.AddSubIterator(hasa)
and.AddSubIterator(subIt)
it = and
case "saver":
all := qs.NodesAllIterator()
if len(stringArgs) > 2 || len(stringArgs) == 0 {
return iterator.NewNull()
}
if len(stringArgs) == 2 {
all.Tagger().Add(stringArgs[1])
} else {
all.Tagger().Add(stringArgs[0])
}
predFixed := qs.FixedIterator()
predFixed.Add(qs.ValueOf(stringArgs[0]))
subAnd := iterator.NewAnd(qs)
subAnd.AddSubIterator(iterator.NewLinksTo(qs, predFixed, quad.Predicate))
subAnd.AddSubIterator(iterator.NewLinksTo(qs, all, quad.Subject))
hasa := iterator.NewHasA(qs, subAnd, quad.Object)
and := iterator.NewAnd(qs)
and.AddSubIterator(hasa)
and.AddSubIterator(subIt)
it = and
case "has":
fixed := qs.FixedIterator()
if len(stringArgs) < 2 {
return iterator.NewNull()
}
for _, name := range stringArgs[1:] {
fixed.Add(qs.ValueOf(name))
}
predFixed := qs.FixedIterator()
predFixed.Add(qs.ValueOf(stringArgs[0]))
subAnd := iterator.NewAnd(qs)
subAnd.AddSubIterator(iterator.NewLinksTo(qs, predFixed, quad.Predicate))
subAnd.AddSubIterator(iterator.NewLinksTo(qs, fixed, quad.Object))
hasa := iterator.NewHasA(qs, subAnd, quad.Subject)
and := iterator.NewAnd(qs)
and.AddSubIterator(hasa)
and.AddSubIterator(subIt)
it = and
case "morphism":
it = base
case "and":
arg, _ := obj.Get("_gremlin_values")
firstArg, _ := arg.Object().Get("0")
if !isVertexChain(firstArg.Object()) {
return iterator.NewNull()
}
argIt := buildIteratorTree(firstArg.Object(), qs)
and := iterator.NewAnd(qs)
and.AddSubIterator(subIt)
and.AddSubIterator(argIt)
it = and
case "back":
arg, _ := obj.Get("_gremlin_back_chain")
argIt := buildIteratorTree(arg.Object(), qs)
and := iterator.NewAnd(qs)
and.AddSubIterator(subIt)
and.AddSubIterator(argIt)
it = and
case "is":
fixed := qs.FixedIterator()
for _, name := range stringArgs {
fixed.Add(qs.ValueOf(name))
}
and := iterator.NewAnd(qs)
and.AddSubIterator(fixed)
and.AddSubIterator(subIt)
it = and
case "or":
arg, _ := obj.Get("_gremlin_values")
firstArg, _ := arg.Object().Get("0")
if !isVertexChain(firstArg.Object()) {
return iterator.NewNull()
}
argIt := buildIteratorTree(firstArg.Object(), qs)
or := iterator.NewOr()
or.AddSubIterator(subIt)
or.AddSubIterator(argIt)
it = or
case "both":
// Hardly the most efficient pattern, but the most general.
// Worth looking into an Optimize() optimization here.
clone := subIt.Clone()
it1 := buildInOutIterator(obj, qs, subIt, false)
it2 := buildInOutIterator(obj, qs, clone, true)
or := iterator.NewOr()
or.AddSubIterator(it1)
or.AddSubIterator(it2)
it = or
case "out":
it = buildInOutIterator(obj, qs, subIt, false)
case "follow":
// Follow a morphism
arg, _ := obj.Get("_gremlin_values")
firstArg, _ := arg.Object().Get("0")
if isVertexChain(firstArg.Object()) {
return iterator.NewNull()
}
it = buildIteratorTreeHelper(firstArg.Object(), qs, subIt)
case "followr":
// Follow a morphism
arg, _ := obj.Get("_gremlin_followr")
if isVertexChain(arg.Object()) {
return iterator.NewNull()
}
it = buildIteratorTreeHelper(arg.Object(), qs, subIt)
case "in":
it = buildInOutIterator(obj, qs, subIt, true)
case "except":
arg, _ := obj.Get("_gremlin_values")
firstArg, _ := arg.Object().Get("0")
if !isVertexChain(firstArg.Object()) {
return iterator.NewNull()
}
allIt := qs.NodesAllIterator()
toComplementIt := buildIteratorTree(firstArg.Object(), qs)
notIt := iterator.NewNot(toComplementIt, allIt)
and := iterator.NewAnd(qs)
and.AddSubIterator(subIt)
and.AddSubIterator(notIt)
it = and
case "in_predicates":
it = buildInOutPredicateIterator(obj, qs, subIt, true)
case "out_predicates":
it = buildInOutPredicateIterator(obj, qs, subIt, false)
}
if it == nil {
panic("Iterator building does not catch the output iterator in some case.")
}
return it
}
func (q *Query) buildIteratorTreeMapInternal(query map[string]interface{}, path Path) (graph.Iterator, error) {
it := iterator.NewAnd(q.ses.qs)
it.AddSubIterator(q.ses.qs.NodesAllIterator())
var err error
err = nil
outputStructure := make(map[string]interface{})
for key, subquery := range query {
optional := false
outputStructure[key] = nil
reverse := false
pred := key
if strings.HasPrefix(pred, "@") {
i := strings.Index(pred, ":")
if i != -1 {
pred = pred[(i + 1):]
}
}
if strings.HasPrefix(pred, "!") {
reverse = true
pred = strings.TrimPrefix(pred, "!")
}
// Other special constructs here
var subit graph.Iterator
if key == "id" {
subit, optional, err = q.buildIteratorTreeInternal(subquery, path.Follow(key))
if err != nil {
return nil, err
}
} else {
var builtIt graph.Iterator
builtIt, optional, err = q.buildIteratorTreeInternal(subquery, path.Follow(key))
if err != nil {
return nil, err
}
subAnd := iterator.NewAnd(q.ses.qs)
predFixed := q.ses.qs.FixedIterator()
predFixed.Add(q.ses.qs.ValueOf(pred))
subAnd.AddSubIterator(iterator.NewLinksTo(q.ses.qs, predFixed, quad.Predicate))
if reverse {
lto := iterator.NewLinksTo(q.ses.qs, builtIt, quad.Subject)
subAnd.AddSubIterator(lto)
hasa := iterator.NewHasA(q.ses.qs, subAnd, quad.Object)
subit = hasa
} else {
lto := iterator.NewLinksTo(q.ses.qs, builtIt, quad.Object)
subAnd.AddSubIterator(lto)
hasa := iterator.NewHasA(q.ses.qs, subAnd, quad.Subject)
subit = hasa
}
}
if optional {
it.AddSubIterator(iterator.NewOptional(subit))
} else {
it.AddSubIterator(subit)
}
}
if err != nil {
return nil, err
}
q.queryStructure[path] = outputStructure
return it, nil
}