Sorting always results in NullPointerException

[rvanzon]

Hi,

I am trying to sort the results of my query, but it always results in a { code: 500 } in the browser, couchdb-lucene outputs:

java.lang.NullPointerException
	at org.apache.lucene.search.SortField.getComparator(SortField.java:340)
	at org.apache.lucene.search.FieldValueHitQueue.<init>(FieldValueHitQueue.java:142)
	at org.apache.lucene.search.FieldValueHitQueue.<init>(FieldValueHitQueue.java:32)
	at org.apache.lucene.search.FieldValueHitQueue$OneComparatorFieldValueHitQueue.<init>(FieldValueHitQueue.java:63)
	at org.apache.lucene.search.FieldValueHitQueue.create(FieldValueHitQueue.java:166)
	at org.apache.lucene.search.TopFieldCollector.create(TopFieldCollector.java:492)
	at org.apache.lucene.search.IndexSearcher$4.newCollector(IndexSearcher.java:562)
	at org.apache.lucene.search.IndexSearcher$4.newCollector(IndexSearcher.java:557)
	at org.apache.lucene.search.IndexSearcher.search(IndexSearcher.java:591)
	at org.apache.lucene.search.IndexSearcher.searchAfter(IndexSearcher.java:577)
	at org.apache.lucene.search.IndexSearcher.search(IndexSearcher.java:504)
	at com.github.rnewson.couchdb.lucene.DatabaseIndexer.search(DatabaseIndexer.java:533)
	at com.github.rnewson.couchdb.lucene.LuceneServlet.doGetInternal(LuceneServlet.java:193)
	at com.github.rnewson.couchdb.lucene.LuceneServlet.doGet(LuceneServlet.java:171)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:687)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
	at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:845)
	at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:583)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
	at org.eclipse.jetty.server.handler.gzip.GzipHandler.handle(GzipHandler.java:459)
	at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1176)
	at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:511)
	at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1106)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:134)
	at org.eclipse.jetty.server.Server.handle(Server.java:524)
	at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:319)
	at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:253)
	at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:273)
	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:95)
	at org.eclipse.jetty.io.SelectChannelEndPoint$2.run(SelectChannelEndPoint.java:93)
	at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.executeProduceConsume(ExecuteProduceConsume.java:303)
	at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.produceConsume(ExecuteProduceConsume.java:148)
	at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.run(ExecuteProduceConsume.java:136)
	at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:671)
	at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:589)
	at java.lang.Thread.run(Thread.java:745)

I tried several indexes, from:

"by_body": {
      "index": "function(doc) { var ret=new Document(); ret.add(doc.body); return ret }"
}

to

"by_text": {
     "index": "function(doc) { var ret=new Document(); 
        ret.add(doc.title, { \"field\": \"text\" }); ret.add(doc.body, { \"field\": \"text\" }); 
        ret.add(doc.publishAt, { \"field\": \"date\", \"type\": \"date\" });  
        return ret }"
},

I am calling the latter with:

http://localhost:5986/_fti/local/nwst-cms-greenkeeper-dev/_design/search/by_text?q=text:keyword&include_docs=true&sort=date

any ideas?

[rvanzon]

Nobody has problems with sorting? Kinda stuck here..

[rnewson]

You'll need to sort on a numeric field or an untokenized field, that's a Lucene restriction.

[rvanzon]

Ok, like we were talking about via Slack. Adding <string> to the query fixes it.

...search/by_text?q=text:keyword&include_docs=true&sort=date<string>

As you mentioned, a fix is underway.

[carrotalan]

+1 for this. Trying to sort via Javascript date object (e.g. createdAt: 2018-02-01T14:26:47.668Z) and cannot get it to work. Either Error 500 without the bit, or no results with the string bit. Followed exactly the same process as @rvanzon

[rnewson]

@carrotalan could you open a new issue with details please?