A Gremlin Implementation of the Gremlin Traversal Machine

~ python

Python 2.7.10 (default, Oct 23 2015, 19:19:21)

[GCC 4.2.1 Compatible Apple LLVM 7.0.0 (clang-700.0.59.5)] on darwin

Type "help", "copyright", "credits" or "license" for more information.

>>> from gremlin_python import statics

>>> from gremlin_python.structure.graph import Graph

>>> from gremlin_python.driver.driver_remote_connection import DriverRemoteConnection

>>> statics.load_statics(globals())

>>>

>>> g = Graph().traversal().withRemote(DriverRemoteConnection('ws://localhost:8182/gremlin','g'))

>>>

>>> g.V().has('name','marko').out('knows').count().next()

2L

>>>

>>> g.V().has('name','marko'). \

...   out('created').in_('created'). \

...   has('name',neq('marko')).dedup().name.toList()

[u'josh', u'peter']

>>>

>>> g.V().has('name','lop').in_('created'). \

...   out('knows').dedup().age.mean().next()

29.5

>>>

>>> g.V().hasLabel('person'). \

...   repeat(both('knows')).times(5). \

...   groupCount().by('name').next()

{u'vadas': 4L, u'marko': 8L, u'josh': 4L}

>>>

$ bin/gremlin.sh

         \,,,/

         (o o)

-----oOOo-(3)-oOOo-----

plugin activated: tinkerpop.server

plugin activated: tinkerpop.utilities

plugin activated: tinkerpop.tinkergraph

gremlin> import static org.apache.tinkerpop.gremlin.util.function.Lambda.function

gremlin> import static org.apache.tinkerpop.gremlin.util.function.Lambda.predicate

gremlin> import static org.apache.tinkerpop.gremlin.util.function.Lambda.consumer

gremlin> g = EmptyGraph.instance().traversal().withRemote(DriverRemoteConnection.using(Cluster.build('localhost').port(8182).create(),'g'))

==>graphtraversalsource[emptygraph[empty], standard]

gremlin>

gremlin> traversal = g.V().has('name','marko').out('knows').values('name'); []

gremlin>

gremlin> g.inject(traversal).

           map(function('it.get().bytecode')).as('bytecode').

           addV('traversal').as('traversal').property('source','g').

           select('bytecode').map(function('it.get().stepInstructions')).unfold().

           project('op','args').as('inst').

             by(function('it.operator')).

             by(function('it.arguments as List')).

           addV('step').as('step').

             property('op', select('op')).

             sideEffect(select('inst').select('args').unfold().as('arg').

                        select('step').property(list,'arg',select(last,'arg'))).

           choose(select('traversal').out('next'),

             addE('next').from(V().where(hasLabel('step').and().not(outE('next'))).where(neq('step'))).to(select('step')),              

             addE('next').from(select('traversal')).to(select('step'))).iterate()

g.V().has('name','marko').out('knows').values('name')

gremlin> g.V().has('source','g').

           repeat(out('next')).until(out('next').count().is(0)).

           path().by(valueMap('source','op','arg'))

==>[[source:[g]],[op:[V]],[op:[has],arg:[name,eq(marko)]],[op:[out],arg:[knows]],[op:[values],arg:[name]]]

gremlin> g.V().hasLabel(within('traversal','step')).drop()

gremlin>

gremlin> traversal = g.V().has('name','marko').

                       repeat(outE('knows','created').identity().inV()).times(2).

                       values('name').groupCount(); []

gremlin>

gremlin> g.inject(traversal).

           map(function('it.get().bytecode')).as('bytecode').

           addV('traversal').

             property('source','g').

             property('bytecode',select('bytecode')).

             property('depth',0L).

           repeat(V().hasLabel('traversal').has('bytecode').

             has('depth',loops()).as('traversal').

             values('bytecode').map(function('it.get().stepInstructions')).unfold().

             project('op','args').as('inst').

               by(function('it.operator')).

               by(function('it.arguments as List')).

             addV('step').as('step').

               property('op', select(last,'inst').select('op')).

               sideEffect(addE('parent').to(select(last,'traversal')).

               select(last,'inst').select('args').unfold().as('arg').

               choose(predicate('it instanceof Bytecode'),

                 addV('traversal').

                   property('source','__').

                   property('bytecode',select(last,'arg')).      

                   property('depth', union(loops(), constant(1)).sum()).

                   addE('child').from(select(last,'step')),

                 select(last,'step').property(list,'arg',select(last,'arg')))).

           choose(select(last,'traversal').not(out('next')),

             addE('next').from(select(last,'traversal')).to(select(last,'step')),

             addE('next').from(select('prev').tail(local,1)).to(select(last,'step'))).

           select(last,'step').store('prev').

           sideEffect(select(last,'traversal').properties('bytecode','depth').drop()))

g.V().has('name','marko').

  repeat(outE('knows','created').identity().inV()).times(2).

  values('name').groupCount()

gremlin> g.V().has('source').as('source').

           order().by(until(__.in('child').count().is(0)).

                      repeat(__.in('child').out('parent')).path().count(local),incr).

           choose(__.in('child'),

                  __.in('child').map(select('source').out('next')),

                  out('next')).

           until(out('next').count().is(0)).repeat(out('next')).

           path().by(valueMap('source','op','arg'))

==>[[source:[g]],[op:[V]],[op:[has],arg:[name,eq(marko)]],[op:[repeat]],[op:[times],arg:[2]],[op:[values],arg:[name]],[op:[groupCount]]]

==>[[source:[__]],[op:[repeat]],[op:[outE],arg:[knows,created]],[op:[identity]],[op:[inV]]]

gremlin> g.V().group().

                 by(label).

                 by(valueMap('name','source','op').fold()).next()

==>software=[{name=[lop]}, {name=[ripple]}]

==>person=[{name=[marko]}, {name=[vadas]}, {name=[josh]}, {name=[peter]}]

==>step=[{op=[groupCount]}, {op=[V]}, {op=[outE]}, {op=[has]}, {op=[identity]}, {op=[repeat]}, {op=[inV]}, {op=[times]}, {op=[values]}]

==>traversal=[{source=[__]}, {source=[g]}]

g.V().has('op','identity').as('step').

  addE('next').

    from(select('step').in('next')).

    to(select('step').out('next')).

  select('step').drop()

gremlin> g.V().has('source').as('source').

           order().by(until(__.in('child').count().is(0)).

                      repeat(__.in('child').out('parent')).path().count(local),incr).

           choose(__.in('child'),

                  __.in('child').map(select('source').out('next')),

                  out('next')).

           until(out('next').count().is(0)).repeat(out('next')).

           path().by(valueMap('source','op','arg'))

==>[[source:[g]],[op:[V]],[op:[has],arg:[name,eq(marko)]],[op:[repeat]],[op:[times],arg:[2]],[op:[values],arg:[name]],[op:[groupCount]]]

==>[[source:[__]],[op:[repeat]],[op:[outE],arg:[knows,created]],[op:[inV]]]

g.V().match(

  __.as('a').out('next').as('b'),

  __.as('a').has('op','outE'),

  __.as('b').has('op','inV')).

addV('step').as('c').

  property('op','out').

  sideEffect(select('a').values('arg').as('arg').

             select('c').property(list,'arg',select('arg'))).

  addE('next').from(select('a').in('next')).to('c').

  choose(select('b').out('next').count().is(gt(0)),

    addE('next').from('c').to(select('b').out('next')),

    identity()).

select('a','b').select(values).unfold().drop()

gremlin> g.V().has('source').as('source').

           order().by(until(__.in('child').count().is(0)).

                      repeat(__.in('child').out('parent')).path().count(local),incr).

           choose(__.in('child'),

                  __.in('child').map(select('source').out('next')),

                  out('next')).

           until(out('next').count().is(0)).repeat(out('next')).

           path().by(valueMap('source','op','arg'))

==>[[source:[g]],[op:[V]],[op:[has],arg:[name,eq(marko)]],[op:[repeat]],[op:[times],arg:[2]],[op:[values],arg:[name]],[op:[groupCount]]]

==>[[source:[__]],[op:[repeat]],[op:[out],arg:[knows,created]]]

gremlin> graph = TinkerGraph.open()

==>tinkergraph[vertices:0 edges:0]

gremlin> graph.io(graphml()).readGraph('data/grateful-dead.xml')

/////////////////////////////////

// Without LazyBarrierStrategy //

/////////////////////////////////

gremlin> g = graph.traversal().withoutStrategies(LazyBarrierStrategy)

==>graphtraversalsource[tinkergraph[vertices:808 edges:8049], standard]

gremlin> clockWithResult(100){

           g.V().has('name','DARK STAR').

             out('followedBy').aggregate('likes').

             in('followedBy').out('followedBy').

               where(not(within('likes'))).

             groupCount().by('name').

             order(local).by(values,decr).

               unfold().limit(10).toList() }

==>19.0969239

==>[CHINA CAT SUNFLOWER=788,SAMSON AND DELILAH=778,UNCLE JOHNS BAND=750,SCARLET BEGONIAS=747,NEW MINGLEWOOD BLUES=726,

    ESTIMATED PROPHET=709,THE MUSIC NEVER STOPPED=699,LOOKS LIKE RAIN=697,BEAT IT ON DOWN THE LINE=661,RAMBLE ON ROSE=656]

//////////////////////////////

// With LazyBarrierStrategy //

//////////////////////////////

gremlin> g = graph.traversal()                                      

==>graphtraversalsource[tinkergraph[vertices:808 edges:8049], standard]

gremlin> clockWithResult(100){

           g.V().has('name','DARK STAR').

             out('followedBy').aggregate('likes').

             in('followedBy').out('followedBy').

               where(not(within('likes'))).

             groupCount().by('name').

             order(local).by(values,decr).

               unfold().limit(10).toList() }

==>1.4836289499999997

==>[CHINA CAT SUNFLOWER=788,SAMSON AND DELILAH=778,UNCLE JOHNS BAND=750,SCARLET BEGONIAS=747,NEW MINGLEWOOD BLUES=726,

    ESTIMATED PROPHET=709,THE MUSIC NEVER STOPPED=699,LOOKS LIKE RAIN=697,BEAT IT ON DOWN THE LINE=661,RAMBLE ON ROSE=656]

///////////////////////////////

// Using Traversal.explain() //

///////////////////////////////

==>Traversal Explanation

===========================================================================================================

Original Traversal                 [GraphStep(vertex,[]), HasStep([name.eq(DARK STAR)]),

                                    VertexStep(OUT[followedBy],vertex), AggregateStep(likes),

                                    VertexStep(IN,[followedBy],vertex), VertexStep(OUT[followedBy],vertex),

                                    WherePredicateStep(without([likes])), GroupCountStep(value(name)),

                                    OrderLocalStep([[values,decr]]), UnfoldStep, RangeGlobalStep(0,10)]

...

Final Traversal                    [TinkerGraphStep(vertex,[name.eq(DARK STAR)]),

                                    VertexStep(OUT[followedBy],vertex), AggregateStep(likes),

                                    VertexStep(IN,[followedBy],vertex), NoOpBarrierStep(2500),

                                    VertexStep(OUT,[followedBy],vertex), NoOpBarrierStep(2500),

                                    WherePredicateStep(without([likes])),

                                    GroupCountStep(value(name)), OrderLocalStep([[values, decr]]),

                                    UnfoldStep, RangeGlobalStep(0,10)]

g.V().as('flatMap').

  has('op',within('out','in','both','values')).

  where(out('next').has('op',neq('barrier')).or().not(out('next'))).

  addV('step').as('barrier').

    property('op','barrier').

    property('arg','2500').

  sideEffect(select('flatMap').outE('next').as('a').

       addE('next').from('barrier').to(select('a').inV()).

       select('a').drop()).

  select('flatMap').addE('next').from('flatMap').to('barrier')

gremlin> g.V().has('source').as('source').

           order().by(until(__.in('child').count().is(0)).

                      repeat(__.in('child').out('parent')).path().count(local),incr).

           choose(__.in('child'),

                  __.in('child').map(select('source').out('next')),

                  out('next')).

           until(out('next').count().is(0)).repeat(out('next')).

           path().by(valueMap('source','op','arg'))

==>[[source:[g]],[op:[V]],[op:[has],arg:[name,eq(marko)]],[op:[repeat]],[op:[times],arg:[2]],[op:[values],arg:[name]],[op:[barrier],arg:[2500]],[op:[groupCount]]]

==>[[source:[__]],[op:[repeat]],[op:[out],arg:[knows,created]],[op:[barrier],arg:[2500]]]

g.V().has('name','marko').

  repeat(outE('knows','created').identity().inV()).times(2).

  values('name').groupCount()

g.V().has('name','marko').

  repeat(out('knows','created').barrier(2500)).times(2).

  values('name').barrier(2500).groupCount()

g.withSack(0).withSideEffect('drain',[1]).withSideEffect('fill',[]).

  V().has('source','g').as('parent').

  repeat(out('next').as('step').

    map(values('arg').fold()).as('args').

    sideEffect(select('drain').unfold().

    choose(select(last,'args').count(local).is(0),

      choose(select(last,'step').by('op')).

        option('V', V().hasLabel(not(within('step','traversal')))).

        option('out',out()).

        option('in',__.in()).

        option('both',both()).

        option('outE',outE()).

        option('inE',inE()).

        option('bothE',bothE()).

        option('inV',inV()).

        option('outV',outV()).

        option('otherV',otherV()).

        option('values',__.values()).

        option('barrier',barrier()).

        option('dedup',dedup()).

        option('repeat',identity()).     // option(none,identity())

        option('fold',identity()).       // option(none,identity())

        option('sum',identity()).        // option(none,identity())

        option('mean',identity()).       // option(none,identity())

        option('min',identity()).        // option(none,identity())

        option('max',identity()).        // option(none,identity())

        option('count',identity()).      // option(none,identity())

        option('groupCount',identity()), // option(none,identity())

      choose(select(last,'step').by('op')).

        option('V', V().hasLabel(not(within('step','traversal'))).where(within('args')).by(id).by()).

        option('has',filter(union(label(),properties().where(within('args')).by(key).by().value()).filter(predicate("it.path(last,'args')[1].test(it.get())")))).

        option('out',outE().where(within('args')).by(label).by().inV()).

        option('in',__.inE().where(within('args')).by(label).by().outV()).

        option('both',bothE().where(within('args')).by(label).by().otherV()).

        option('outE',outE().where(within('args')).by(label).by()).

        option('inE',inE().where(within('args')).by(label).by()).

        option('bothE',bothE().where(within('args')).by(label).by()).

        option('values',properties().where(within('args')).by(key).by().value()).

        option('barrier',barrier()).

        option('times',identity())).     // option(none,identity())

      store('fill')).

    sideEffect(consumer("it.sideEffects('drain').clear()")).

    sideEffect(select('fill').unfold().store('drain')).

    sideEffect(consumer("it.sideEffects('fill').clear()")).

    select(last,'step').

    choose(has('op','repeat').and().out('next').has('op','times'),

      select(last,'step').as('parent').sack(assign).by(out('next').values('arg')).out('child').as('step'),

      choose(select(last,'parent').has('op','repeat').and().out('next').count().is(0),

        choose(sack().is(gt(1)),

          sack(minus).by(constant(1)).select(last,'parent').out('child').as('step'),

          select(last,'parent').as('step').out('parent').as('parent').select(last,'step')),

        identity()))).

  until(out('next').count().is(0)).

  select('drain').

  choose(select(last,'step').has('op',within('fold','sum','mean','min','max','count','groupCount')), // option(none,identity())

    choose(select(last,'step').by('op')).

      option('fold',identity()).

      option('sum',map(unfold().sum())).

      option('mean',map(unfold().mean())).

      option('min',map(unfold().min())).

      option('max',map(unfold().max())).

      option('count',map(unfold().count())).

      option('groupCount',map(unfold().groupCount())),

    unfold()).toList() 

==>[ripple:1,lop:1]

/////////////////////////////////////

// Gremlin-Based Traversal Machine //

/////////////////////////////////////

gremlin> clockWithResult(100){ gremlin(g,

  g.V().has('name','marko').

    repeat(outE().identity().inV()).times(2).

    values('name').

    groupCount()) }

==>18.23885611

==>[[ripple:1,lop:1]]

//////////////////////////////////

// Java-Based Traversal Machine //

//////////////////////////////////

gremlin> clockWithResult(100) {

  g.V().has('name','marko').

    repeat(outE().identity().inV()).times(2).

    values('name').

    groupCount().toList() }

==>0.45385166

==>[[ripple:1,lop:1]]

gremlin> gremlin(g, g.V().has('name','marko').out('knows').count())

==>2

gremlin> gremlin(g,

  g.V().has('name','marko').

    out('created').in('created').

    has('name',neq('marko')).dedup().values('name'))

==>josh

==>peter

gremlin> gremlin(g,

  g.V().has('name','lop').in('created').

    out('knows').values('age').mean())

==>29.5

gremlin> gremlin(g,

  g.V().hasLabel('person').

    repeat(both('knows')).times(5).

    values('name').groupCount())

==>[vadas:4,josh:4,marko:8]

g.addV('message').property('text','Welcome to the machine.').

  addE('bellow').to(V().has('source','g'))