FDN-3924 Add InterfaceTypesRewriter

src/main/scala/io/apibuilder/builders/ApiBuilderServiceBuilders.scala

@@ -1,8 +1,7 @@
 package io.apibuilder.builders
 
 import java.util.UUID
-
-import io.apibuilder.spec.v0.models.{Annotation, Apidoc, Application, Attribute, Body, Contact, Deprecation, Enum, EnumValue, Field, Header, Import, Info, License, Method, Model, Operation, Organization, Parameter, ParameterLocation, Resource, Response, ResponseCode, ResponseCodeInt, Service, Union, UnionType}
+import io.apibuilder.spec.v0.models.{Annotation, Apidoc, Application, Attribute, Body, Contact, Deprecation, Enum, EnumValue, Field, Header, Import, Info, Interface, License, Method, Model, Operation, Organization, Parameter, ParameterLocation, Resource, Response, ResponseCode, ResponseCodeInt, Service, Union, UnionType}
 import io.apibuilder.validation.{ApiBuilderType, MultiService}
 import play.api.libs.json.{JsObject, Json}
 
@@ -26,6 +25,7 @@ trait ApiBuilderServiceBuilders {
     headers: Seq[Header] = Nil,
     imports: Seq[Import] = Nil,
     enums: Seq[Enum] = Nil,
+    interfaces: Seq[Interface] = Nil,
     unions: Seq[Union] = Nil,
     models: Seq[Model] = Nil,
     resources: Seq[Resource] = Nil,
@@ -45,6 +45,7 @@ trait ApiBuilderServiceBuilders {
       headers = headers,
       imports = imports,
       enums = enums,
+      interfaces = interfaces,
       unions = unions,
       models = models,
       resources = resources,
@@ -147,6 +148,24 @@ trait ApiBuilderServiceBuilders {
     Info(license = license, contact = contact)
   }
 
+  def makeInterface(
+    name: String,
+    plural: String,
+    fields: Seq[Field],
+    description: Option[String] = None,
+    deprecation: Option[Deprecation] = None,
+    attributes: Seq[Attribute] = Nil
+  ): Interface = {
+    Interface(
+      name = name,
+      plural = plural,
+      description = description,
+      deprecation = deprecation,
+      fields = fields,
+      attributes = attributes
+    )
+  }
+
   def makeUnion(
     name: String = random(),
     plural: String = random(),

src/main/scala/io/apibuilder/rewriter/InterfaceTypesRewriter.scala

@@ -0,0 +1,18 @@
+package io.apibuilder.rewriter
+
+import io.apibuilder.validation.{ApiBuilderType, MultiService, ScalarType}
+
+// Inspired by UnionTypesMustBeModelsRewriter
+object InterfaceTypesRewriter extends MultiServiceRewriter {
+  override def rewrite(multiService: MultiService): MultiService = {
+    val interfaceNames = multiService.allInterfaces.map(_.qualified).toSet
+
+    val rewritten = TypeRewriter {
+      case t: ApiBuilderType if interfaceNames.contains(t.qualified) => ScalarType.ObjectType
+      case t: ApiBuilderType => t
+      case t: ScalarType => t
+    }.rewrite(multiService)
+
+    rewritten
+  }
+}

src/main/scala/io/apibuilder/rewriter/MinimalTypesRewriter.scala

@@ -1,7 +1,7 @@
 package io.apibuilder.rewriter
 
 import apibuilder.{ApiBuilderHelper, ApiBuilderHelperImpl}
-import io.apibuilder.validation.{ApiBuilderType, MultiService}
+import io.apibuilder.validation.{ApiBuilderService, ApiBuilderType, MultiService, ScalarType}
 
 import scala.annotation.tailrec
 
@@ -24,6 +24,7 @@ case class MinimalTypesRewriter(types: Iterable[ApiBuilderType]) extends Default
           service = s.service.copy(
             enums = svcTypes.collect { case t: ApiBuilderType.Enum => t }.map(_.`enum`),
             models = svcTypes.collect { case t: ApiBuilderType.Model => t }.map(_.model),
+            interfaces = svcTypes.collect { case t: ApiBuilderType.Interface => t }.map(_.interface),
             unions = svcTypes.collect { case t: ApiBuilderType.Union => t }.map(_.union),
           )
         )

src/main/scala/io/apibuilder/rewriter/UnionsToModelsRewriter.scala

@@ -26,6 +26,7 @@ object UnionsToModelsRewriter extends DefaultRewriter {
         unions = newTypes.collect { case e: ApiBuilderType.Union => e.union },
         enums = service.service.enums ++ newTypes.collect { case e: ApiBuilderType.Enum => e.`enum` },
         models = service.service.models ++ newTypes.collect { case m: ApiBuilderType.Model => m.model },
+        interfaces = service.service.interfaces ++ newTypes.collect { case m: ApiBuilderType.Interface => m.interface },
       )
     )
   }

src/main/scala/io/apibuilder/validation/JsonValidator.scala

@@ -129,7 +129,9 @@ case class ValidatedJsonValidator(services: List[ApiBuilderService]) {
   private def findType(service: ApiBuilderService, typeName: String): Option[AnyType] = {
     service.enums.find(_.name.equalsIgnoreCase(typeName)) orElse {
       service.models.find(_.name.equalsIgnoreCase(typeName)) orElse {
-        service.unions.find(_.name.equalsIgnoreCase(typeName))
+        service.unions.find(_.name.equalsIgnoreCase(typeName)) orElse {
+          service.interfaces.find(_.name.equalsIgnoreCase(typeName))
+        }
       }
     }
   }