Unexpected token 'S', "SPARQL-QUE"... is not valid JSON for entities with many predicates

[ate47]

I was searching the entity wd:Q39790431 and I received the error Unexpected token 'S', "SPARQL-QUE"... is not valid JSON,

When I look in the logs, I get this response from Blazegraph:

SPARQL-QUERY: queryStr=
      CONSTRUCT {
        # "Simple" triples
        ?sub ?p ?o .
      
        # Statements
        ?sub ?pred ?obj .
        ?pred rdfs:label ?predLabel .
        ?obj ?pred2 ?obj2 .
        ?pred2 rdfs:label ?pred2Label .
        ?obj2 rdfs:label ?obj2Label .
      } WHERE {
          # Select the subject
          BIND(<http://www.wikidata.org/entity/Q39790431> as ?sub)
        
          # Find "simple" triples
          ?sub ?p ?o .
          FILTER((!(STRSTARTS(STR(?p), "http://www.wikidata.org/prop/direct/"))) && (!(STRSTARTS(STR(?o), "http://www.wikidata.org/entity/statement/"))))
        
          # Find triples that have a statement as object
          ?sub ?pred ?stmt .
          FILTER(STRSTARTS(STR(?pred), "http://www.wikidata.org/prop/P"))
          ?stmt ?pred2 ?obj2 .
          BIND(BNODE(STR(?stmt)) AS ?obj) # Replace the statement IRI with a bnode
        
          # Find label of predicates p:PXXX
          OPTIONAL {
            VALUES ?link0 { wikibase:directClaim wikibase:directClaimNormalized wikibase:claim wikibase:statementProperty wikibase:statementValue wikibase:statementValueNormalized wikibase:qualifier wikibase:qualifierValue wikibase:qualifierValueNormalized wikibase:reference wikibase:referenceValue wikibase:referenceValueNormalized }
            ?predEntity ?link0 ?pred .
            OPTIONAL {
              ?predEntity rdfs:label ?predLabel .
              FILTER (LANG(?predLabel) = "en")
            }
          }
        
          # Find label of statement predicates (predicates inside statements)
          OPTIONAL {
            VALUES ?link1 { wikibase:directClaim wikibase:directClaimNormalized wikibase:claim wikibase:statementProperty wikibase:statementValue wikibase:statementValueNormalized wikibase:qualifier wikibase:qualifierValue wikibase:qualifierValueNormalized wikibase:reference wikibase:referenceValue wikibase:referenceValueNormalized }
            ?pred2Entity ?link1 ?pred2 .
            OPTIONAL {
              ?pred2Entity rdfs:label ?pred2Label .
              FILTER (LANG(?pred2Label) = "en")
            }
          }

          # Find label of statement objects (objects inside statements)
          OPTIONAL {
            ?obj2 rdfs:label ?obj2Label .
            FILTER (LANG(?obj2Label) = "en")
          }
      }
    
java.util.concurrent.TimeoutException
	at java.util.concurrent.FutureTask.get(FutureTask.java:205)
	at com.bigdata.rdf.sail.webapp.BigdataServlet.submitApiTask(BigdataServlet.java:292)
	at com.bigdata.rdf.sail.webapp.QueryServlet.doSparqlQuery(QueryServlet.java:678)
	at com.bigdata.rdf.sail.webapp.QueryServlet.doGet(QueryServlet.java:290)
	at com.bigdata.rdf.sail.webapp.RESTServlet.doGet(RESTServlet.java:240)
	at com.bigdata.rdf.sail.webapp.MultiTenancyServlet.doGet(MultiTenancyServlet.java:273)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:687)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
	at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:865)
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1655)
	at org.wikidata.query.rdf.blazegraph.throttling.ThrottlingFilter.doFilter(ThrottlingFilter.java:320)
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642)
	at org.wikidata.query.rdf.blazegraph.throttling.SystemOverloadFilter.doFilter(SystemOverloadFilter.java:82)
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642)
	at ch.qos.logback.classic.helpers.MDCInsertingServletFilter.doFilter(MDCInsertingServletFilter.java:49)
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642)
	at org.wikidata.query.rdf.blazegraph.filters.QueryEventSenderFilter.doFilter(QueryEventSenderFilter.java:116)
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642)
	at org.wikidata.query.rdf.blazegraph.filters.ClientIPFilter.doFilter(ClientIPFilter.java:43)
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642)
	at org.wikidata.query.rdf.blazegraph.filters.JWTIdentityFilter.doFilter(JWTIdentityFilter.java:66)
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642)
	at org.wikidata.query.rdf.blazegraph.filters.RealAgentFilter.doFilter(RealAgentFilter.java:33)
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642)
	at org.wikidata.query.rdf.blazegraph.filters.RequestConcurrencyFilter.doFilter(RequestConcurrencyFilter.java:50)
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1634)
	at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:533)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:146)
	at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:548)
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)
	at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:257)
	at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1595)
	at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:255)
	at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1340)
	at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:203)
	at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:473)
	at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1564)
	at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:201)
	at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1242)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:144)
	at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:220)
	at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:126)
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)
	at org.eclipse.jetty.server.Server.handle(Server.java:503)
	at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:364)
	at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:260)
	at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:305)
	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:103)
	at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:118)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:333)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:310)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:168)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:126)
	at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:366)
	at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:765)
	at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:683)
	at java.lang.Thread.run(Thread.java:750)

maybe reducing the complexity of the query would help, but a better message for the Timeout would be better