Make interpreter creation effectful

benchmarks/src/main/scala/caliban/GraphQLBenchmarks.scala

@@ -144,7 +144,7 @@ class GraphQLBenchmarks {
     )
   )
 
-  val interpreter: GraphQLInterpreter[Any, CalibanError] = graphQL(resolver).interpreter
+  val interpreter: GraphQLInterpreter[Any, CalibanError] = zioRuntime.unsafeRun(graphQL(resolver).interpreter)
 
   @Benchmark
   def simpleCaliban(): Unit = {

core/src/main/scala/caliban/GraphQL.scala

@@ -1,5 +1,6 @@
 package caliban
 
+import caliban.CalibanError.ValidationError
 import caliban.Rendering.renderTypes
 import caliban.execution.Executor
 import caliban.introspection.Introspector
@@ -73,10 +74,15 @@ trait GraphQL[-R] { self =>
   /**
    * Creates an interpreter from your API. A GraphQLInterpreter is a wrapper around your API that allows
    * adding some middleware around the query execution.
+   * Fails with a [[caliban.CalibanError.ValidationError]] if the schema is invalid.
    */
-  final def interpreter: GraphQLInterpreter[R, CalibanError] =
-    (query: String, operationName: Option[String], variables: Map[String, InputValue], skipValidation: Boolean) =>
-      self.execute(query, operationName, variables, skipValidation)
+  final def interpreter: IO[ValidationError, GraphQLInterpreter[R, CalibanError]] =
+    Validator
+      .validateSchema(rootType)
+      .as {
+        (query: String, operationName: Option[String], variables: Map[String, InputValue], skipValidation: Boolean) =>
+          self.execute(query, operationName, variables, skipValidation)
+      }
 
   /**
    * Attaches a function that will wrap one of the stages of query processing

core/src/main/scala/caliban/validation/Validator.scala

@@ -25,6 +25,18 @@ object Validator {
   def validate(document: Document, rootType: RootType): IO[ValidationError, Unit] =
     check(document, rootType).unit
 
+  /**
+   * Verifies that the given schema is valid. Fails with a [[caliban.CalibanError.ValidationError]] otherwise.
+   */
+  def validateSchema(rootType: RootType): IO[ValidationError, Unit] =
+    IO.foreach(rootType.types.values) { t =>
+        t.kind match {
+          case __TypeKind.ENUM => validateEnum(t)
+          case _               => IO.unit
+        }
+      }
+      .unit
+
   /**
    * Prepare the request for execution.
    * Fails with a [[caliban.CalibanError.ValidationError]] otherwise.
@@ -272,14 +284,14 @@ object Validator {
                 "Defined fragments must be used within a document."
               )
             )
-          else if (detectCycles(context, f))
+          else
             IO.fail(
-              ValidationError(
-                s"Fragment '${f.name}' forms a cycle.",
-                "The graph of fragment spreads must not form any cycles including spreading itself. Otherwise an operation could infinitely spread or infinitely execute on cycles in the underlying data."
+                ValidationError(
+                  s"Fragment '${f.name}' forms a cycle.",
+                  "The graph of fragment spreads must not form any cycles including spreading itself. Otherwise an operation could infinitely spread or infinitely execute on cycles in the underlying data."
+                )
               )
-            )
-          else IO.unit
+              .when(detectCycles(context, f))
       )
       .unit
   }
@@ -379,12 +391,11 @@ object Validator {
   private def validateField(context: Context, field: Field, currentType: __Type): IO[ValidationError, Unit] =
     IO.when(field.name != "__typename") {
       IO.fromOption(currentType.fields(__DeprecatedArgs(Some(true))).getOrElse(Nil).find(_.name == field.name))
-        .mapError(
-          _ =>
-            ValidationError(
-              s"Field '${field.name}' does not exist on type '${Rendering.renderTypeName(currentType)}'.",
-              "The target field of a field selection must be defined on the scoped type of the selection set. There are no limitations on alias names."
-            )
+        .asError(
+          ValidationError(
+            s"Field '${field.name}' does not exist on type '${Rendering.renderTypeName(currentType)}'.",
+            "The target field of a field selection must be defined on the scoped type of the selection set. There are no limitations on alias names."
+          )
         )
         .flatMap { f =>
           validateFields(context, field.selectionSet, Types.innerType(f.`type`())) *>
@@ -550,6 +561,18 @@ object Validator {
         )
     }
 
+  private def validateEnum(t: __Type): IO[ValidationError, Unit] =
+    t.enumValues(__DeprecatedArgs(Some(true))) match {
+      case Some(_ :: _) => IO.unit
+      case _ =>
+        IO.fail(
+          ValidationError(
+            s"Enum ${t.name} doesn't contain any values",
+            "An Enum type must define one or more unique enum values."
+          )
+        )
+    }
+
   case class Context(
     document: Document,
     rootType: RootType,

core/src/test/scala/caliban/execution/ExecutionSpec.scala

@@ -28,7 +28,7 @@ object ExecutionSpec
             }""")
 
           assertM(
-            interpreter.execute(query).map(_.data.toString),
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
             equalTo("""{"amos":{"name":"Amos Burton"}}""")
           )
         },
@@ -42,7 +42,7 @@ object ExecutionSpec
             }""")
 
           assertM(
-            interpreter.execute(query).map(_.data.toString),
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
             equalTo(
               """{"characters":[{"name":"James Holden"},{"name":"Naomi Nagata"},{"name":"Amos Burton"},{"name":"Alex Kamal"},{"name":"Chrisjen Avasarala"},{"name":"Josephus Miller"},{"name":"Roberta Draper"}]}"""
             )
@@ -59,7 +59,7 @@ object ExecutionSpec
             }""")
 
           assertM(
-            interpreter.execute(query).map(_.data.toString),
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
             equalTo(
               """{"characters":[{"name":"Alex Kamal","nicknames":[]},{"name":"Roberta Draper","nicknames":["Bobbie","Gunny"]}]}"""
             )
@@ -75,7 +75,7 @@ object ExecutionSpec
             }""")
 
           assertM(
-            interpreter.execute(query).map(_.data.toString),
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
             equalTo("""{"charactersIn":[{"name":"Alex Kamal"}]}""")
           )
         },
@@ -94,7 +94,7 @@ object ExecutionSpec
              }""")
 
           assertM(
-            interpreter.execute(query).map(_.data.toString),
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
             equalTo("""{"amos":{"name":"Amos Burton","nicknames":[]},"naomi":{"name":"Naomi Nagata","nicknames":[]}}""")
           )
         },
@@ -112,7 +112,7 @@ object ExecutionSpec
              }""")
 
           assertM(
-            interpreter.execute(query).map(_.data.toString),
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
             equalTo("""{"amos":{"name":"Amos Burton"}}""")
           )
         },
@@ -131,7 +131,7 @@ object ExecutionSpec
              }""")
 
           assertM(
-            interpreter.execute(query).map(_.data.toString),
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
             equalTo("""{"amos":{"name":"Amos Burton","role":{"shipName":"Rocinante"}}}""")
           )
         },
@@ -145,7 +145,7 @@ object ExecutionSpec
                }""")
 
           assertM(
-            interpreter.execute(query).map(_.data.toString),
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
             equalTo(
               """{"characters":[{"name":"James Holden"},{"name":"Naomi Nagata"},{"name":"Amos Burton"},{"name":"Alex Kamal"},{"name":"Chrisjen Avasarala"},{"name":"Josephus Miller"},{"name":"Roberta Draper"}]}"""
             )
@@ -158,7 +158,7 @@ object ExecutionSpec
                  deleteCharacter(name: "Amos Burton")
                }""")
 
-          assertM(interpreter.execute(query).map(_.data.toString), equalTo("""{"deleteCharacter":{}}"""))
+          assertM(interpreter.flatMap(_.execute(query)).map(_.data.toString), equalTo("""{"deleteCharacter":{}}"""))
         },
         testM("variable") {
           val interpreter = graphQL(resolver).interpreter
@@ -170,7 +170,7 @@ object ExecutionSpec
              }""")
 
           assertM(
-            interpreter.execute(query, None, Map("name" -> StringValue("Amos Burton"))).map(_.data.toString),
+            interpreter.flatMap(_.execute(query, None, Map("name" -> StringValue("Amos Burton")))).map(_.data.toString),
             equalTo("""{"amos":{"name":"Amos Burton"}}""")
           )
         },
@@ -184,7 +184,10 @@ object ExecutionSpec
                }
              }""")
 
-          assertM(interpreter.execute(query).map(_.data.toString), equalTo("""{"amos":{"name":"Amos Burton"}}"""))
+          assertM(
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
+            equalTo("""{"amos":{"name":"Amos Burton"}}""")
+          )
         },
         testM("include directive") {
           val interpreter = graphQL(resolver).interpreter
@@ -197,7 +200,7 @@ object ExecutionSpec
              }""")
 
           assertM(
-            interpreter.execute(query, None, Map("included" -> BooleanValue(false))).map(_.data.toString),
+            interpreter.flatMap(_.execute(query, None, Map("included" -> BooleanValue(false)))).map(_.data.toString),
             equalTo("""{"amos":{"name":"Amos Burton"}}""")
           )
         },
@@ -212,7 +215,10 @@ object ExecutionSpec
                }
              }""")
 
-          assertM(interpreter.execute(query).map(_.data.toString), equalTo("""{"map":[{"key":3,"value":"ok"}]}"""))
+          assertM(
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
+            equalTo("""{"map":[{"key":3,"value":"ok"}]}""")
+          )
         },
         testM("test Either") {
           case class Test(either: Either[Int, String])
@@ -225,7 +231,10 @@ object ExecutionSpec
                }
              }""")
 
-          assertM(interpreter.execute(query).map(_.data.toString), equalTo("""{"either":{"left":null,"right":"ok"}}"""))
+          assertM(
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
+            equalTo("""{"either":{"left":null,"right":"ok"}}""")
+          )
         },
         testM("test UUID") {
           case class IdArgs(id: UUID)
@@ -237,18 +246,19 @@ object ExecutionSpec
              }""")
 
           assertM(
-            interpreter.execute(query).map(_.data.toString),
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
             equalTo("""{"test":"be722453-d97d-48c2-b535-9badd1b5d4c9"}""")
           )
         },
         testM("mapError") {
           import io.circe.syntax._
           case class Test(either: Either[Int, String])
-          val interpreter = graphQL(RootResolver(Test(Right("ok")))).interpreter.mapError(_ => "my custom error")
-          val query       = """query{}"""
+          val api   = graphQL(RootResolver(Test(Right("ok"))))
+          val query = """query{}"""
 
           for {
-            result <- interpreter.execute(query)
+            interpreter <- api.interpreter
+            result      <- interpreter.mapError(_ => "my custom error").execute(query)
           } yield assert(result.errors, equalTo(List("my custom error"))) &&
             assert(result.asJson.noSpaces, equalTo("""{"data":null,"errors":[{"message":"my custom error"}]}"""))
         },
@@ -264,7 +274,7 @@ object ExecutionSpec
               |  id
               |}""".stripMargin
           assertM(
-            interpreter.execute(query).map(_.data.toString),
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
             equalTo("""{"name":"name","id":2}""")
           )
         },
@@ -283,7 +293,7 @@ object ExecutionSpec
                 }
               }""")
           assertM(
-            interpreter.execute(query).map(_.errors),
+            interpreter.flatMap(_.execute(query)).map(_.errors),
             equalTo(
               List(
                 ExecutionError(
@@ -305,7 +315,7 @@ object ExecutionSpec
              }""")
 
           assertM(
-            interpreter.execute(query).map(_.data.toString),
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
             equalTo("""{"test":[1,2,3]}""")
           )
         },
@@ -320,7 +330,7 @@ object ExecutionSpec
              }""")
 
           assertM(
-            interpreter.execute(query).map(_.data.toString),
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
             equalTo("""{"test":<stream>}""")
           )
         },
@@ -335,7 +345,7 @@ object ExecutionSpec
              }""")
 
           assertM(
-            interpreter.execute(query).map(_.data.toString),
+            interpreter.flatMap(_.execute(query)).map(_.data.toString),
             equalTo("""{"test":{"a":333}}""")
           )
         },
@@ -349,7 +359,7 @@ object ExecutionSpec
                }
              }""")
 
-          assertM(interpreter.execute(query).map(_.data.toString), equalTo("""{"i":{"id":"ok"}}"""))
+          assertM(interpreter.flatMap(_.execute(query)).map(_.data.toString), equalTo("""{"i":{"id":"ok"}}"""))
         }
       )
     )

core/src/test/scala/caliban/introspection/IntrospectionSpec.scala

@@ -107,7 +107,7 @@ object IntrospectionSpec
           val interpreter = graphQL(resolverIO).interpreter
 
           assertM(
-            interpreter.execute(fullIntrospectionQuery).map(_.data.toString),
+            interpreter.flatMap(_.execute(fullIntrospectionQuery)).map(_.data.toString),
             equalTo(
               """{"__schema":{"queryType":{"name":"QueryIO"},"mutationType":null,"subscriptionType":null,"types":[{"kind":"SCALAR","name":"Boolean","description":null,"fields":null,"inputFields":null,"interfaces":null,"enumValues":null,"possibleTypes":null},{"kind":"OBJECT","name":"Captain","description":null,"fields":[{"name":"shipName","description":null,"args":[],"type":{"kind":"NON_NULL","name":null,"ofType":{"kind":"SCALAR","name":"String","ofType":null}},"isDeprecated":false,"deprecationReason":null}],"inputFields":null,"interfaces":[],"enumValues":null,"possibleTypes":null},{"kind":"OBJECT","name":"Character","description":null,"fields":[{"name":"name","description":null,"args":[],"type":{"kind":"NON_NULL","name":null,"ofType":{"kind":"SCALAR","name":"String","ofType":null}},"isDeprecated":false,"deprecationReason":null},{"name":"nicknames","description":null,"args":[],"type":{"kind":"NON_NULL","name":null,"ofType":{"kind":"LIST","name":null,"ofType":{"kind":"NON_NULL","name":null,"ofType":{"kind":"SCALAR","name":"String","ofType":null}}}},"isDeprecated":false,"deprecationReason":null},{"name":"origin","description":null,"args":[],"type":{"kind":"NON_NULL","name":null,"ofType":{"kind":"ENUM","name":"Origin","ofType":null}},"isDeprecated":false,"deprecationReason":null},{"name":"role","description":null,"args":[],"type":{"kind":"UNION","name":"Role","ofType":null},"isDeprecated":false,"deprecationReason":null}],"inputFields":null,"interfaces":[],"enumValues":null,"possibleTypes":null},{"kind":"OBJECT","name":"Engineer","description":null,"fields":[{"name":"shipName","description":null,"args":[],"type":{"kind":"NON_NULL","name":null,"ofType":{"kind":"SCALAR","name":"String","ofType":null}},"isDeprecated":false,"deprecationReason":null}],"inputFields":null,"interfaces":[],"enumValues":null,"possibleTypes":null},{"kind":"OBJECT","name":"Mechanic","description":null,"fields":[{"name":"shipName","description":null,"args":[],"type":{"kind":"NON_NULL","name":null,"ofType":{"kind":"SCALAR","name":"String","ofType":null}},"isDeprecated":false,"deprecationReason":null}],"inputFields":null,"interfaces":[],"enumValues":null,"possibleTypes":null},{"kind":"ENUM","name":"Origin","description":null,"fields":null,"inputFields":null,"interfaces":null,"enumValues":[{"name":"BELT","description":null,"isDeprecated":false,"deprecationReason":null},{"name":"EARTH","description":null,"isDeprecated":false,"deprecationReason":null},{"name":"MARS","description":null,"isDeprecated":false,"deprecationReason":null}],"possibleTypes":null},{"kind":"OBJECT","name":"Pilot","description":null,"fields":[{"name":"shipName","description":null,"args":[],"type":{"kind":"NON_NULL","name":null,"ofType":{"kind":"SCALAR","name":"String","ofType":null}},"isDeprecated":false,"deprecationReason":null}],"inputFields":null,"interfaces":[],"enumValues":null,"possibleTypes":null},{"kind":"OBJECT","name":"QueryIO","description":"Queries","fields":[{"name":"characters","description":"Return all characters from a given origin","args":[{"name":"origin","description":null,"type":{"kind":"ENUM","name":"Origin","ofType":null},"defaultValue":null}],"type":{"kind":"NON_NULL","name":null,"ofType":{"kind":"LIST","name":null,"ofType":{"kind":"NON_NULL","name":null,"ofType":{"kind":"OBJECT","name":"Character","ofType":null}}}},"isDeprecated":false,"deprecationReason":null},{"name":"character","description":null,"args":[{"name":"name","description":null,"type":{"kind":"NON_NULL","name":null,"ofType":{"kind":"SCALAR","name":"String","ofType":null}},"defaultValue":null}],"type":{"kind":"OBJECT","name":"Character","ofType":null},"isDeprecated":true,"deprecationReason":"Use `characters`"}],"inputFields":null,"interfaces":[],"enumValues":null,"possibleTypes":null},{"kind":"UNION","name":"Role","description":null,"fields":null,"inputFields":null,"interfaces":null,"enumValues":null,"possibleTypes":[{"kind":"OBJECT","name":"Captain","ofType":null},{"kind":"OBJECT","name":"Engineer","ofType":null},{"kind":"OBJECT","name":"Mechanic","ofType":null},{"kind":"OBJECT","name":"Pilot","ofType":null}]},{"kind":"SCALAR","name":"String","description":null,"fields":null,"inputFields":null,"interfaces":null,"enumValues":null,"possibleTypes":null}],"directives":[{"name":"skip","description":"The @skip directive may be provided for fields, fragment spreads, and inline fragments, and allows for conditional exclusion during execution as described by the if argument.","locations":["FIELD","FRAGMENT_SPREAD","INLINE_FRAGMENT"],"args":[{"name":"if","description":null,"type":{"kind":"SCALAR","name":"Boolean","ofType":null},"defaultValue":null}]},{"name":"include","description":"The @include directive may be provided for fields, fragment spreads, and inline fragments, and allows for conditional inclusion during execution as described by the if argument.","locations":["FIELD","FRAGMENT_SPREAD","INLINE_FRAGMENT"],"args":[{"name":"if","description":null,"type":{"kind":"SCALAR","name":"Boolean","ofType":null},"defaultValue":null}]}]}}"""
             )

core/src/test/scala/caliban/validation/ValidationSpec.scala

@@ -1,10 +1,11 @@
 package caliban.validation
 
 import caliban.CalibanError
+import caliban.CalibanError.ValidationError
 import caliban.GraphQL._
 import caliban.Macros.gqldoc
 import caliban.TestUtils._
-import zio.UIO
+import zio.IO
 import zio.test.Assertion._
 import zio.test._
 
@@ -13,8 +14,8 @@ object ValidationSpec
       val gql         = graphQL(resolverWithSubscription)
       val interpreter = gql.interpreter
 
-      def check(query: String, expectedMessage: String): UIO[TestResult] = {
-        val io = interpreter.execute(query).map(_.errors.headOption)
+      def check(query: String, expectedMessage: String): IO[ValidationError, TestResult] = {
+        val io = interpreter.flatMap(_.execute(query)).map(_.errors.headOption)
         assertM(io, isSome(hasField[CalibanError, String]("msg", _.msg, equalTo(expectedMessage))))
       }