Fix OpenAPI constraints for array schemas

build.sbt

@@ -148,12 +148,13 @@ lazy val tests: ProjectMatrix = (projectMatrix in file("tests"))
       "io.circe" %% "circe-generic" % Versions.circe,
       "com.softwaremill.common" %% "tagging" % "2.2.1",
       scalaTest,
-      "com.softwaremill.macwire" %% "macros" % "2.3.7" % "provided"
-    ),
+      "com.softwaremill.macwire" %% "macros" % "2.3.7" % "provided",
+      "com.beachape" %% "enumeratum" % Versions.enumeratum,
+      "com.beachape" %% "enumeratum-circe" % Versions.enumeratum),
     libraryDependencies ++= loggerDependencies
   )
   .jvmPlatform(scalaVersions = allScalaVersions)
-  .dependsOn(core, circeJson)
+  .dependsOn(core, circeJson, enumeratum)
 
 // integrations
 

docs/openapi-docs/src/main/scala/sttp/tapir/docs/openapi/schema/TSchemaToOSchema.scala

@@ -54,11 +54,18 @@ private[schema] class TSchemaToOSchema(schemaReferenceMapper: SchemaReferenceMap
         )
     }
 
+    val primitiveValidators = typeData.schema.schemaType match {
+      case TSchemaType.SArray(_) => asPrimitiveValidators(typeData.validator)
+      case _                     => asPrimitiveValidatorsDeep(typeData.validator)
+    }
+    val wholeNumbers = typeData.schema.schemaType match {
+      case TSchemaType.SInteger => true
+      case _                    => false
+    }
+
     result
       .map(addMetadata(_, typeData.schema))
-      .map(
-        addConstraints(_, asPrimitiveValidators(typeData.validator), typeData.schema.schemaType.isInstanceOf[TSchemaType.SInteger.type])
-      )
+      .map(addConstraints(_, primitiveValidators, wholeNumbers))
   }
 
   private def addMetadata(oschema: OSchema, tschema: TSchema[_]): OSchema = {

docs/openapi-docs/src/main/scala/sttp/tapir/docs/openapi/schema/package.scala

@@ -24,14 +24,27 @@ package object schema {
 
   private[schema] def asPrimitiveValidators(v: Validator[_]): Seq[Validator.Primitive[_]] = {
     v match {
-      case Validator.Mapped(wrapped, _)             => asPrimitiveValidators(wrapped)
-      case Validator.All(validators)                => validators.flatMap(asPrimitiveValidators)
-      case Validator.Any(validators)                => validators.flatMap(asPrimitiveValidators)
-      case Validator.CollectionElements(wrapped, _) => asPrimitiveValidators(wrapped)
-      case Validator.Product(_)                     => Nil
-      case Validator.Coproduct(_)                   => Nil
-      case Validator.OpenProduct(_)                 => Nil
-      case bv: Validator.Primitive[_]               => List(bv)
+      case Validator.Mapped(wrapped, _)       => asPrimitiveValidators(wrapped)
+      case Validator.All(validators)          => validators.flatMap(asPrimitiveValidators)
+      case Validator.Any(validators)          => validators.flatMap(asPrimitiveValidators)
+      case Validator.CollectionElements(_, _) => Nil
+      case Validator.Product(_)               => Nil
+      case Validator.Coproduct(_)             => Nil
+      case Validator.OpenProduct(_)           => Nil
+      case bv: Validator.Primitive[_]         => List(bv)
+    }
+  }
+
+  private[schema] def asPrimitiveValidatorsDeep(v: Validator[_]): Seq[Validator.Primitive[_]] = {
+    v match {
+      case Validator.Mapped(wrapped, _)            => asPrimitiveValidatorsDeep(wrapped)
+      case Validator.All(validators)               => validators.flatMap(asPrimitiveValidatorsDeep)
+      case Validator.Any(validators)               => validators.flatMap(asPrimitiveValidatorsDeep)
+      case Validator.CollectionElements(mapped, _) => asPrimitiveValidatorsDeep(mapped)
+      case Validator.Product(_)                    => Nil
+      case Validator.Coproduct(_)                  => Nil
+      case Validator.OpenProduct(_)                => Nil
+      case bv: Validator.Primitive[_]              => List(bv)
     }
   }
 

docs/openapi-docs/src/test/resources/expected_valid_enum_array.yml

@@ -0,0 +1,34 @@
+openapi: 3.0.1
+info:
+  title: Fruits
+  version: '1.0'
+paths:
+  /enum-test:
+    get:
+      operationId: getEnum-test
+      responses:
+        '200':
+          description: ''
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/FruitWithEnum'
+components:
+  schemas:
+    FruitWithEnum:
+      required:
+        - fruit
+        - amount
+      type: object
+      properties:
+        fruit:
+          type: string
+        amount:
+          type: integer
+        fruitType:
+          type: array
+          items:
+            type: string
+            enum:
+              - APPLE
+              - PEAR

docs/openapi-docs/src/test/resources/expected_valid_int_array.yml

@@ -0,0 +1,21 @@
+openapi: 3.0.1
+info:
+  title: Entities
+  version: '1.0'
+paths:
+  /:
+    get:
+      operationId: getRoot
+      requestBody:
+        content:
+          application/json:
+            schema:
+                type: array
+                items:
+                  type: integer
+                  minimum: 1
+                  maximum: 10
+        required: false
+      responses:
+        '200':
+          description: ''

docs/openapi-docs/src/test/scala/sttp/tapir/docs/openapi/VerifyYamlTest.scala

@@ -6,6 +6,7 @@ import io.circe.generic.auto._
 import sttp.model.{Method, StatusCode}
 import sttp.tapir.EndpointIO.Example
 import sttp.tapir._
+import sttp.tapir.codec.enumeratum.TapirCodecEnumeratum
 import sttp.tapir.docs.openapi.dtos.Book
 import sttp.tapir.docs.openapi.dtos.a.{Pet => APet}
 import sttp.tapir.docs.openapi.dtos.b.{Pet => BPet}
@@ -20,7 +21,7 @@ import scala.io.Source
 import org.scalatest.funsuite.AnyFunSuite
 import org.scalatest.matchers.should.Matchers
 
-class VerifyYamlTest extends AnyFunSuite with Matchers {
+class VerifyYamlTest extends AnyFunSuite with Matchers with TapirCodecEnumeratum {
   val all_the_way: Endpoint[(FruitAmount, String), Unit, (FruitAmount, Int), Nothing] = endpoint
     .in(("fruit" / path[String] / "amount" / path[Int]).mapTo(FruitAmount))
     .in(query[String]("color"))
@@ -573,6 +574,16 @@ class VerifyYamlTest extends AnyFunSuite with Matchers {
     actualYamlNoIndent shouldBe expectedYaml
   }
 
+  test("render validator for additional properties of array elements") {
+    val expectedYaml = loadYaml("expected_valid_int_array.yml")
+
+    val actualYaml = Validation.in_valid_int_array
+      .toOpenAPI(Info("Entities", "1.0"))
+      .toYaml
+    val actualYamlNoIndent = noIndentation(actualYaml)
+    actualYamlNoIndent shouldBe expectedYaml
+  }
+
   test("render enum validator for classes") {
     val expectedYaml = loadYaml("expected_valid_enum_class.yml")
 
@@ -613,6 +624,16 @@ class VerifyYamlTest extends AnyFunSuite with Matchers {
     actualYamlNoIndent shouldBe expectedYaml
   }
 
+  test("use enum validator for array elements") {
+    val out_enum_array = endpoint.in(("enum-test")).out(jsonBody[FruitWithEnum])
+    val expectedYaml = loadYaml("expected_valid_enum_array.yml")
+
+    val actualYaml = List(out_enum_array).toOpenAPI(Info("Fruits", "1.0")).toYaml
+    val actualYamlNoIndent = noIndentation(actualYaml)
+
+    actualYamlNoIndent shouldBe expectedYaml
+  }
+
   test("support example of list and not-list types") {
     val expectedYaml = loadYaml("expected_examples_of_list_and_not_list_types.yml")
     val actualYaml = endpoint.post

tests/src/main/scala/sttp/tapir/tests/FruitAmount.scala

@@ -1,6 +1,11 @@
 package sttp.tapir.tests
 
+import enumeratum.EnumEntry
+import enumeratum.Enum
 import sttp.tapir._
+import sttp.tapir.codec.enumeratum.TapirCodecEnumeratum
+
+import scala.collection.immutable
 
 case class FruitAmount(fruit: String, amount: Int)
 
@@ -12,8 +17,19 @@ case class ValidFruitAmount(fruit: StringWrapper, amount: IntWrapper)
 
 case class ColorWrapper(color: Color)
 
+case class FruitWithEnum(fruit: String, amount: Int, fruitType: List[FruitType])
+
 sealed trait Entity {
   def name: String
 }
 case class Person(name: String, age: Int) extends Entity
 case class Organization(name: String) extends Entity
+
+sealed trait FruitType extends EnumEntry
+
+object FruitType extends Enum[FruitType] {
+  case object APPLE extends FruitType
+  case object PEAR extends FruitType
+
+  override def values: immutable.IndexedSeq[FruitType] = findValues
+}

tests/src/main/scala/sttp/tapir/tests/package.scala

@@ -414,6 +414,14 @@ package object tests {
       endpoint.in(jsonBody[ColorWrapper])
     }
 
+    val in_valid_int_array: Endpoint[List[IntWrapper], Unit, Unit, Nothing] = {
+      implicit val schemaForIntWrapper: Schema[IntWrapper] = Schema(SchemaType.SInteger)
+      implicit val encoder: Encoder[IntWrapper] = Encoder.encodeInt.contramap(_.v)
+      implicit val decode: Decoder[IntWrapper] = Decoder.decodeInt.map(IntWrapper.apply)
+      implicit val v: Validator[IntWrapper] = Validator.all(Validator.min(1), Validator.max(10)).contramap(_.v)
+      endpoint.in(jsonBody[List[IntWrapper]])
+    }
+
     val allEndpoints: Set[Endpoint[_, _, _, _]] = wireSet[Endpoint[_, _, _, _]]
   }