update INSERT on TDB2 results in org.apache.jena.dboe.transaction.txn.TransactionException: Not in a transaction

[Laura Morales]

assembler.ttl
=============
PREFIX : <http://example.org/>
PREFIX ja: <http://jena.hpl.hp.com/2005/11/Assembler#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX tdb: <http://jena.hpl.hp.com/2008/tdb#>
PREFIX tdb2: <http://jena.apache.org/2016/tdb#>
PREFIX text: <http://jena.apache.org/text#>

:dataset a ja:RDFDataset ;
    ja:namedGraph [ ja:graphName :g1 ;
                    ja:graph :graph1 ] ;
    ja:namedGraph [ ja:graphName :g2 ;
                    ja:graph :graph2 ] ;
    .

:graph1 a tdb2:GraphTDB2 ;
    tdb2:location "g1" .

:graph2 a tdb2:GraphTDB2 ;
    tdb2:location "g2" .

query.rq
========
PREFIX : <http://example.org/>

INSERT
{
    GRAPH :g2 {
        ?s ?p ?o
    }
}
WHERE {
    GRAPH :g1 {
        ?s ?p ?o
    }
}

commands
========

$ sparql --desc assembler.ttl "ask {}"
Ask => Yes

$ update --desc assembler.ttl --update query.rq
org.apache.jena.dboe.transaction.txn.TransactionException: Not in a transaction
        at 
org.apache.jena.dboe.transaction.txn.TransactionalComponentLifecycle.checkTxn(TransactionalComponentLifecycle.java:417)
        at 
org.apache.jena.dboe.trans.bplustree.BPlusTree.getRootRead(BPlusTree.java:159)
        at 
org.apache.jena.dboe.trans.bplustree.BPlusTree.iterator(BPlusTree.java:348)
        at 
org.apache.jena.tdb2.store.tupletable.TupleIndexRecord.all(TupleIndexRecord.java:251)
        at 
org.apache.jena.tdb2.store.tupletable.TupleTable.find(TupleTable.java:148)
        at 
org.apache.jena.tdb2.store.nodetupletable.NodeTupleTableConcrete.find(NodeTupleTableConcrete.java:161)
        at 
org.apache.jena.tdb2.solver.StageMatchTuple.makeNextStage(StageMatchTuple.java:96)
        at 
org.apache.jena.tdb2.solver.StageMatchTuple.makeNextStage(StageMatchTuple.java:37)
        at 
org.apache.jena.atlas.iterator.RepeatApplyIterator.hasNext(RepeatApplyIterator.java:48)
        at 
org.apache.jena.tdb2.solver.SolverLib$IterAbortable.hasNext(SolverLib.java:192)
        at org.apache.jena.atlas.iterator.Iter$2.hasNext(Iter.java:265)
        at 
org.apache.jena.sparql.engine.iterator.QueryIterPlainWrapper.hasNextBinding(QueryIterPlainWrapper.java:53)
        at 
org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
        at 
org.apache.jena.sparql.engine.main.iterator.QueryIterGraph$QueryIterGraphInner.hasNextBinding(QueryIterGraph.java:121)
        at 
org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
        at 
org.apache.jena.sparql.engine.iterator.QueryIterRepeatApply.hasNextBinding(QueryIterRepeatApply.java:74)
        at 
org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
        at 
org.apache.jena.sparql.engine.iterator.QueryIteratorWrapper.hasNextBinding(QueryIteratorWrapper.java:39)
        at 
org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
        at 
org.apache.jena.sparql.engine.iterator.QueryIteratorWrapper.hasNextBinding(QueryIteratorWrapper.java:39)
        at 
org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
        at java.util.Iterator.forEachRemaining(Iterator.java:115)
        at org.apache.jena.atlas.data.DataBag.addAll(DataBag.java:94)
        at 
org.apache.jena.sparql.modify.UpdateEngineWorker.visit(UpdateEngineWorker.java:410)
        at 
org.apache.jena.sparql.modify.request.UpdateModify.visit(UpdateModify.java:100)
        at 
org.apache.jena.sparql.modify.UpdateVisitorSink.send(UpdateVisitorSink.java:46)
        at 
org.apache.jena.sparql.modify.UpdateVisitorSink.send(UpdateVisitorSink.java:26)
        at org.apache.jena.atlas.iterator.Iter.sendToSink(Iter.java:562)
        at org.apache.jena.atlas.iterator.Iter.sendToSink(Iter.java:569)
        at 
org.apache.jena.sparql.modify.UpdateProcessorBase.execute(UpdateProcessorBase.java:59)
        at arq.update.execOneFile(update.java:105)
        at arq.update.execUpdate(update.java:81)
        at arq.cmdline.CmdUpdate.exec(CmdUpdate.java:63)
        at jena.cmd.CmdMain.mainMethod(CmdMain.java:93)
        at jena.cmd.CmdMain.mainRun(CmdMain.java:58)
        at jena.cmd.CmdMain.mainRun(CmdMain.java:45)
        at arq.update.main(update.java:49)


What/Who is causing this problem? Am I using the wrong command-line tool? And 
is there a way that I can fix this?
Note: if I use Fuseki everything seems to work fine. That is, if I use the same 
dataset definition in the fuseki assembler file, and if I issue the same update 
query from the fuseki web UI. But if I use the "update" command line tool 
instead, I get a transaction error. I'm not sure what fuseki is doing 
differently...