Pagination using offset/length is not working

[jonasanso]

Executing

client.execute {
  search into "index" query
    Query(query = Some("text"),
      attributesToRetrieve = Some(Seq("objectID")),
      attributesToHighlight = Some(Nil),
      offset = Some(25),
      length = Some(10)
    )
}.recover {
  case NonFatal(e) => throw new AlgoliaException("fail", e)
}

Throws this exception

Exception in thread "main" com.depop.product.algolia.AlgoliaException: Error executing fail
	at Main$$anonfun$1.applyOrElse(Main.scala:29)
	at Main$$anonfun$1.applyOrElse(Main.scala:28)
	at scala.runtime.AbstractPartialFunction.apply(AbstractPartialFunction.scala:36)
	at scala.util.Failure$$anonfun$recover$1.apply(Try.scala:216)
	at scala.util.Try$.apply(Try.scala:192)
	at scala.util.Failure.recover(Try.scala:216)
	at scala.concurrent.Future$$anonfun$recover$1.apply(Future.scala:326)
	at scala.concurrent.Future$$anonfun$recover$1.apply(Future.scala:326)
	at scala.concurrent.impl.CallbackRunnable.run(Promise.scala:36)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)
Caused by: algolia.AlgoliaClientException: Failed on last retry
	at algolia.AlgoliaClient$$anonfun$request$1.applyOrElse(AlgoliaClient.scala:153)
	at algolia.AlgoliaClient$$anonfun$request$1.applyOrElse(AlgoliaClient.scala:149)
	at scala.concurrent.Future$$anonfun$recoverWith$1.apply(Future.scala:346)
	at scala.concurrent.Future$$anonfun$recoverWith$1.apply(Future.scala:345)
	... 4 more
Caused by: org.json4s.package$MappingException: No usable value for page
Did not find value which can be converted into int
	at org.json4s.reflect.package$.fail(package.scala:93)
	at org.json4s.Extraction$ClassInstanceBuilder.org$json4s$Extraction$ClassInstanceBuilder$$buildCtorArg(Extraction.scala:514)
	at org.json4s.Extraction$ClassInstanceBuilder$$anonfun$14.apply(Extraction.scala:534)
	at org.json4s.Extraction$ClassInstanceBuilder$$anonfun$14.apply(Extraction.scala:534)
	at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:234)
	at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:234)
	at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:59)
	at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:48)
	at scala.collection.TraversableLike$class.map(TraversableLike.scala:234)
	at scala.collection.AbstractTraversable.map(Traversable.scala:104)
	at org.json4s.Extraction$ClassInstanceBuilder.org$json4s$Extraction$ClassInstanceBuilder$$instantiate(Extraction.scala:522)
	at org.json4s.Extraction$ClassInstanceBuilder$$anonfun$result$8.apply(Extraction.scala:585)
	at org.json4s.Extraction$ClassInstanceBuilder$$anonfun$result$8.apply(Extraction.scala:580)
	at org.json4s.Extraction$.org$json4s$Extraction$$customOrElse(Extraction.scala:594)
	at org.json4s.Extraction$ClassInstanceBuilder.result(Extraction.scala:580)
	at org.json4s.Extraction$.extract(Extraction.scala:389)
	at org.json4s.Extraction$.extract(Extraction.scala:39)
	at org.json4s.ExtractableJsonAstNode.extract(ExtractableJsonAstNode.scala:21)
	at algolia.AlgoliaHttpClient$$anon$1.onCompleted(AlgoliaHttpClient.scala:72)

The response from algolia servers does not contain some fields required in the class algolia.SearchResult.

{"hits":[{"objectID":"55696231"},...],"nbHits":5240,"offset":25,"length":10,"processingTimeMS":3,"exhaustiveNbHits":false,"query":"text","params":"attributesToRetrieve=objectID&query=text&offset=25&length=10&attributesToHighlight="}

The specification says page and hitsPerPage are not returned when we search using offset/length
https://www.algolia.com/doc/api-reference/api-methods/search/
But SearchResult has them defined as mandatory and the parsing of the response crashes.

https://github.com/algolia/algoliasearch-client-scala/blob/master/src/main/scala/algolia/responses/SearchResult.scala

This can be solved having a one to one mapping with the specification or allowing to provide alternative classes to parse the response or maybe in a totally different way. Personally I do not even need page and hitsPerPage in the SearchResult class so that offers a third solution to my issue, but I imagine others might rely on them.

Please let me know if there is any other input needed.

[jonasanso]

Great! Quite fast turn around.
The code is in master, but does not seem to be released in a new version of the library.
What is the process you follow for releases?

[jonasanso]

Looks like there were 3 fields optional. I reported 2 in the issue and you fixed a different one.

I think this change does not totally fix the problem as hitsPerPage is still mandatory.

[ElPicador]

I've forgot to add my changes, so the previous PR was incomplete 🙄.

It's fixed in master. I'm releasing a new version 1.24.1 right now