Fix pagination directive failing on empty responses (#182)v1.11.7

2 files changed, 65 insertions, 19 deletions

diff --git a/src/main/scala/xyz/driver/core/rest/package.scala b/src/main/scala/xyz/driver/core/rest/package.scala
index 4858fa7..d4d01df 100644
--- a/src/main/scala/xyz/driver/core/rest/package.scala
+++ b/src/main/scala/xyz/driver/core/rest/package.scala
@@ -258,7 +258,7 @@ object `package` {
     optionalPagination { pagination =>
       onSuccess(handler(pagination)) {
         case ListResponse(resultPart, ListResponse.Meta(count, _, pageSize)) =>
-          val pageCount = (count / pageSize) + (if (count % pageSize == 0) 0 else 1)
+          val pageCount = if (pageSize == 0) 0 else (count / pageSize) + (if (count % pageSize == 0) 0 else 1)
           val headers = List(
             RawHeader(ContextHeaders.ResourceCount, count.toString),
             RawHeader(ContextHeaders.PageCount, pageCount.toString))
diff --git a/src/test/scala/xyz/driver/core/rest/RestTest.scala b/src/test/scala/xyz/driver/core/rest/RestTest.scala
index 5403765..e742462 100644
--- a/src/test/scala/xyz/driver/core/rest/RestTest.scala
+++ b/src/test/scala/xyz/driver/core/rest/RestTest.scala
@@ -1,6 +1,6 @@
 package xyz.driver.core.rest
 
-import akka.http.scaladsl.marshalling.ToResponseMarshallable
+import akka.http.javadsl.server.MalformedRequestContentRejection
 import akka.http.scaladsl.model.StatusCodes
 import akka.http.scaladsl.server.{Directives, Route, ValidationRejection}
 import akka.http.scaladsl.testkit.ScalatestRouteTest
@@ -75,31 +75,77 @@ class RestTest extends WordSpec with Matchers with ScalatestRouteTest with Direc
     }
   }
 
-  "completeWithPagination directive" should {
+  "completeWithPagination directive" when {
     import akka.http.scaladsl.marshallers.sprayjson.SprayJsonSupport._
     import spray.json.DefaultJsonProtocol._
 
     val data = Seq.fill(103)(Random.alphanumeric.take(10).mkString)
-    val route: Route = rest.completeWithPagination[String] {
-      case Some(pagination) =>
-        val filtered = data.slice(pagination.offset, pagination.offset + pagination.pageSize)
-        Future.successful(ListResponse(filtered, data.size, Some(pagination)))
-      case None => Future.successful(ListResponse(data, data.size, None))
-    }
+    val route: Route =
+      parameter('empty.as[Boolean] ? false) { isEmpty =>
+        completeWithPagination[String] {
+          case Some(pagination) if isEmpty =>
+            Future.successful(ListResponse(Seq(), 0, Some(pagination)))
+          case Some(pagination) =>
+            val filtered = data.slice(pagination.offset, pagination.offset + pagination.pageSize)
+            Future.successful(ListResponse(filtered, data.size, Some(pagination)))
+          case None if isEmpty => Future.successful(ListResponse(Seq(), 0, None))
+          case None            => Future.successful(ListResponse(data, data.size, None))
+        }
+      }
 
-    "return a response with pagination headers when pagination has been passed" in {
-      Get("/?pageNumber=2&pageSize=10") ~> route ~> check {
-        responseAs[Seq[String]] shouldBe data.slice(10, 20)
-        header(ContextHeaders.ResourceCount).map(_.value) should contain("103")
-        header(ContextHeaders.PageCount).map(_.value) should contain("11")
+    "pagination is defined" should {
+      "return a response with pagination headers" in {
+        Get("/?pageNumber=2&pageSize=10") ~> route ~> check {
+          responseAs[Seq[String]] shouldBe data.slice(10, 20)
+          header(ContextHeaders.ResourceCount).map(_.value) should contain("103")
+          header(ContextHeaders.PageCount).map(_.value) should contain("11")
+        }
+      }
+
+      "disallow pageSize <= 0" in {
+        Get("/?pageNumber=2&pageSize=0") ~> route ~> check {
+          rejection shouldBe a[ValidationRejection]
+        }
+
+        Get("/?pageNumber=2&pageSize=-1") ~> route ~> check {
+          rejection shouldBe a[ValidationRejection]
+        }
+      }
+
+      "disallow pageNumber <= 0" in {
+        Get("/?pageNumber=0&pageSize=10") ~> route ~> check {
+          rejection shouldBe a[ValidationRejection]
+        }
+
+        Get("/?pageNumber=-1&pageSize=10") ~> route ~> check {
+          rejection shouldBe a[ValidationRejection]
+        }
+      }
+
+      "return PageCount == 0 if returning an empty list" in {
+        Get("/?empty=true&pageNumber=2&pageSize=10") ~> route ~> check {
+          responseAs[Seq[String]] shouldBe empty
+          header(ContextHeaders.ResourceCount).map(_.value) should contain("0")
+          header(ContextHeaders.PageCount).map(_.value) should contain("0")
+        }
       }
     }
 
-    "return a response with pagination headers when no pagination has been passed" in {
-      Get("/") ~> route ~> check {
-        responseAs[Seq[String]] shouldBe data
-        header(ContextHeaders.ResourceCount).map(_.value) should contain("103")
-        header(ContextHeaders.PageCount).map(_.value) should contain("1")
+    "pagination is not defined" should {
+      "return a response with pagination headers and PageCount == 1" in {
+        Get("/") ~> route ~> check {
+          responseAs[Seq[String]] shouldBe data
+          header(ContextHeaders.ResourceCount).map(_.value) should contain("103")
+          header(ContextHeaders.PageCount).map(_.value) should contain("1")
+        }
+      }
+
+      "return PageCount == 0 if returning an empty list" in {
+        Get("/?empty=true") ~> route ~> check {
+          responseAs[Seq[String]] shouldBe empty
+          header(ContextHeaders.ResourceCount).map(_.value) should contain("0")
+          header(ContextHeaders.PageCount).map(_.value) should contain("0")
+        }
       }
     }
   }