Map Rendering broken

[LorenzBuehmann]

Hi devs,

currently I can see 2 issues on the public demos:

1. OSM Planet seems to be down at all (Nov 14th, 11am)
2. For OSM Germany (I guess it's not dataset specific, but the query works here and is needed for the Map view)

The original query is

PREFIX osm: <https://www.openstreetmap.org/>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX osmt: <https://www.openstreetmap.org/wiki/Key:>
PREFIX geo: <http://www.opengis.net/ont/geosparql#>
PREFIX osmway: <https://www.openstreetmap.org/way/>
SELECT * WHERE {
  ?way osmt:railway "rail" .
  ?way rdf:type osm:way .
  ?way geo:hasGeometry ?geom
} LIMIT 10

which returns a result but the Map View fails with

{
    "exception": "Invalid SPARQL query: Token \"}\": no viable alternative at input 'LIMIT10}'",
    "metadata": {
        "line": 1,
        "positionInLine": 367,
        "query": "PREFIX osm:  PREFIX rdf:  PREFIX osmt:  PREFIX geo:  PREFIX osmway:  SELECT * WHERE { ?way osmt:railway \"rail\" . ?way rdf:type osm:way . ?way geo:hasGeometry ?geom } LIMIT 10}",
        "startIndex": 367,
        "stopIndex": 367
    },
    "query": "PREFIX osm:  PREFIX rdf:  PREFIX osmt:  PREFIX geo:  PREFIX osmway:  SELECT * WHERE { ?way osmt:railway \"rail\" . ?way rdf:type osm:way . ?way geo:hasGeometry ?geom } LIMIT 10}",
    "resultsize": 0,
    "status": "ERROR",
    "time": {
        "computeResult": 0,
        "total": 0
    }
}

so it looks like the widget seems to always append a closing } to the query which indeed results in invalid syntax error when querying QLever (or any other triple store).

Also, removing the LIMIT 10 from the query makes the widget to append the } and then in addition append the max value for Integer:

{
    "exception": "Invalid SPARQL query: Token \"}\": mismatched input '}' expecting ",
    "metadata": {
        "line": 1,
        "positionInLine": 358,
        "query": "PREFIX osm:  PREFIX rdf:  PREFIX osmt:  PREFIX geo:  PREFIX osmway:  SELECT * WHERE { ?way osmt:railway \"rail\" . ?way rdf:type osm:way . ?way geo:hasGeometry ?geom }} LIMIT 18446744073709551615",
        "startIndex": 358,
        "stopIndex": 358
    },
    "query": "PREFIX osm:  PREFIX rdf:  PREFIX osmt:  PREFIX geo:  PREFIX osmway:  SELECT * WHERE { ?way osmt:railway \"rail\" . ?way rdf:type osm:way . ?way geo:hasGeometry ?geom }} LIMIT 18446744073709551615",
    "resultsize": 0,
    "status": "ERROR",
    "time": {
        "computeResult": 0,
        "total": 0
    }
}

so it sends }} LIMIT 18446744073709551615 to the QLever endpoint. That LIMIT with 2^64-1 looks rather redundant to me by the way.

I think the error is the same for both queries in rewriting the query somehow. Did you change the code recently, it was working before for me for sure?

[hannahbast]

@LorenzBuehmann Thanks for the feedback!

@1: We had an involuntarily denial-of-service attack by one of our own students :-) it's fixed now and https://qlever.cs.uni-freiburg.de/osm-planet is up again.

@2: The Map view currently doesn't work for SELECT *. When you replace the * by explicit variable names, it works: https://qlever.cs.uni-freiburg.de/osm-planet/Fap8TK

[LorenzBuehmann]

Hi Hannah! Thanks for the quick response.

1. Yeah, I can see those things happening :D
2. understand - from the code I could see that you're working with string modifications and regex instead of a SPARQL parser - I guess that's why some things are more difficult for now

One more question:
It looks like you removed the geospatial materialization for now? Or moved to a different predicate? At least I can't get any query with osm2rdf:contains_area working, especially those example seem to be outdated because of that? I can see that geo:sfContains works - but I don't know which predicates are available right now?

Maybe I keep forgetting, was osm2rdf:contains_area some kind of predicate being rewritten by the query parser or a proper predicate in the dataset?