func orMorphism(p *Path) morphism {
return morphism{
Name: "or",
Reversal: func() morphism { return orMorphism(p) },
Apply: func(qs graph.QuadStore, it graph.Iterator) graph.Iterator {
subIt := p.BuildIteratorOn(qs)
and := iterator.NewOr()
and.AddSubIterator(it)
and.AddSubIterator(subIt)
return and
},
}
}
// orMorphism is the union, vice intersection, of a path and the current iterator.
func orMorphism(p *Path) morphism {
return morphism{
Name: "or",
Reversal: func(ctx *context) (morphism, *context) { return orMorphism(p), ctx },
Apply: func(qs graph.QuadStore, in graph.Iterator, ctx *context) (graph.Iterator, *context) {
itR := p.BuildIteratorOn(qs)
or := iterator.NewOr()
or.AddSubIterator(in)
or.AddSubIterator(itR)
return or, ctx
},
}
}
// orMorphism is the union, vice intersection, of a path and the current iterator.
func orMorphism(p *Path) morphism {
return morphism{
Name: "or",
Reversal: func() morphism { return orMorphism(p) },
Apply: func(qs graph.QuadStore, itL graph.Iterator) graph.Iterator {
itR := p.BuildIteratorOn(qs)
or := iterator.NewOr()
or.AddSubIterator(itL)
or.AddSubIterator(itR)
return or
},
}
}
func bothMorphism(tags []string, via ...interface{}) morphism {
return morphism{
Name: "in",
Reversal: func(ctx *context) (morphism, *context) { return bothMorphism(tags, via...), ctx },
Apply: func(qs graph.QuadStore, in graph.Iterator, ctx *context) (graph.Iterator, *context) {
path := buildViaPath(qs, via...)
inSide := inOutIterator(path, in, true, tags)
outSide := inOutIterator(path, in.Clone(), false, tags)
or := iterator.NewOr()
or.AddSubIterator(inSide)
or.AddSubIterator(outSide)
return or, ctx
},
}
}
func buildIteratorTreeHelper(obj *otto.Object, ts graph.TripleStore, base graph.Iterator) graph.Iterator {
var it graph.Iterator
it = base
// TODO: Better error handling
kindVal, _ := obj.Get("_gremlin_type")
stringArgs := getStringArgs(obj)
var subIt graph.Iterator
prevVal, _ := obj.Get("_gremlin_prev")
if !prevVal.IsObject() {
subIt = base
} else {
subIt = buildIteratorTreeHelper(prevVal.Object(), ts, base)
}
kind, _ := kindVal.ToString()
switch kind {
case "vertex":
if len(stringArgs) == 0 {
it = ts.NodesAllIterator()
} else {
fixed := ts.FixedIterator()
for _, name := range stringArgs {
fixed.Add(ts.ValueOf(name))
}
it = fixed
}
case "tag":
it = subIt
for _, tag := range stringArgs {
it.Tagger().Add(tag)
}
case "save":
all := ts.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 := ts.FixedIterator()
predFixed.Add(ts.ValueOf(stringArgs[0]))
subAnd := iterator.NewAnd()
subAnd.AddSubIterator(iterator.NewLinksTo(ts, predFixed, quad.Predicate))
subAnd.AddSubIterator(iterator.NewLinksTo(ts, all, quad.Object))
hasa := iterator.NewHasA(ts, subAnd, quad.Subject)
and := iterator.NewAnd()
and.AddSubIterator(hasa)
and.AddSubIterator(subIt)
it = and
case "saver":
all := ts.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 := ts.FixedIterator()
predFixed.Add(ts.ValueOf(stringArgs[0]))
subAnd := iterator.NewAnd()
subAnd.AddSubIterator(iterator.NewLinksTo(ts, predFixed, quad.Predicate))
subAnd.AddSubIterator(iterator.NewLinksTo(ts, all, quad.Subject))
hasa := iterator.NewHasA(ts, subAnd, quad.Object)
and := iterator.NewAnd()
and.AddSubIterator(hasa)
and.AddSubIterator(subIt)
it = and
case "has":
fixed := ts.FixedIterator()
if len(stringArgs) < 2 {
return iterator.NewNull()
}
for _, name := range stringArgs[1:] {
fixed.Add(ts.ValueOf(name))
}
predFixed := ts.FixedIterator()
predFixed.Add(ts.ValueOf(stringArgs[0]))
subAnd := iterator.NewAnd()
subAnd.AddSubIterator(iterator.NewLinksTo(ts, predFixed, quad.Predicate))
subAnd.AddSubIterator(iterator.NewLinksTo(ts, fixed, quad.Object))
hasa := iterator.NewHasA(ts, subAnd, quad.Subject)
and := iterator.NewAnd()
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(), ts)
and := iterator.NewAnd()
and.AddSubIterator(subIt)
and.AddSubIterator(argIt)
it = and
case "back":
arg, _ := obj.Get("_gremlin_back_chain")
argIt := buildIteratorTree(arg.Object(), ts)
and := iterator.NewAnd()
and.AddSubIterator(subIt)
and.AddSubIterator(argIt)
it = and
case "is":
fixed := ts.FixedIterator()
for _, name := range stringArgs {
fixed.Add(ts.ValueOf(name))
}
and := iterator.NewAnd()
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(), ts)
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, ts, subIt, false)
it2 := buildInOutIterator(obj, ts, clone, true)
or := iterator.NewOr()
or.AddSubIterator(it1)
or.AddSubIterator(it2)
it = or
case "out":
it = buildInOutIterator(obj, ts, 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(), ts, subIt)
case "followr":
// Follow a morphism
arg, _ := obj.Get("_gremlin_followr")
if isVertexChain(arg.Object()) {
return iterator.NewNull()
}
it = buildIteratorTreeHelper(arg.Object(), ts, subIt)
case "in":
it = buildInOutIterator(obj, ts, subIt, true)
}
return it
}
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
}