Shadow service typename filter (#637)

lib/src/main/java/graphql/nadel/NadelExecutionHints.kt

@@ -3,9 +3,9 @@ package graphql.nadel
 import graphql.nadel.hints.AllDocumentVariablesHint
 import graphql.nadel.hints.LegacyOperationNamesHint
 import graphql.nadel.hints.NadelDeferSupportHint
+import graphql.nadel.hints.NadelServiceTypenameShadowingHint
 import graphql.nadel.hints.NadelSharedTypeRenamesHint
 import graphql.nadel.hints.NadelShortCircuitEmptyQueryHint
-import graphql.nadel.hints.NadelValidationBlueprintHint
 import graphql.nadel.hints.NadelVirtualTypeSupportHint
 import graphql.nadel.hints.NewResultMergerAndNamespacedTypename
 
@@ -17,6 +17,7 @@ data class NadelExecutionHints(
     val sharedTypeRenames: NadelSharedTypeRenamesHint,
     val shortCircuitEmptyQuery: NadelShortCircuitEmptyQueryHint,
     val virtualTypeSupport: NadelVirtualTypeSupportHint,
+    val serviceTypenameShadowing: NadelServiceTypenameShadowingHint,
 ) {
     /**
      * Returns a builder with the same field values as this object.
@@ -36,6 +37,7 @@ data class NadelExecutionHints(
         private var shortCircuitEmptyQuery = NadelShortCircuitEmptyQueryHint { false }
         private var sharedTypeRenames = NadelSharedTypeRenamesHint { false }
         private var virtualTypeSupport = NadelVirtualTypeSupportHint { false }
+        private var serviceTypenameShadowing = NadelServiceTypenameShadowingHint.default
 
         constructor()
 
@@ -81,6 +83,11 @@ data class NadelExecutionHints(
             return this
         }
 
+        fun serviceTypenameShadowing(flag: NadelServiceTypenameShadowingHint): Builder {
+            serviceTypenameShadowing = flag
+            return this
+        }
+
         fun build(): NadelExecutionHints {
             return NadelExecutionHints(
                 legacyOperationNames,
@@ -90,6 +97,7 @@ data class NadelExecutionHints(
                 sharedTypeRenames,
                 shortCircuitEmptyQuery,
                 virtualTypeSupport,
+                serviceTypenameShadowing,
             )
         }
     }

lib/src/main/java/graphql/nadel/engine/blueprint/NadelExecutionBlueprint.kt

@@ -83,8 +83,8 @@ inline fun <reified T : NadelFieldInstruction> NadelOverallExecutionBlueprint.ge
 
 internal class NadelOverallExecutionBlueprintMigrator(
     private val hint: NadelValidationBlueprintHint,
-    private val old: NadelOverallExecutionBlueprint,
-    private val new: Lazy<NadelOverallExecutionBlueprint?>,
+    val old: NadelOverallExecutionBlueprint,
+    val new: Lazy<NadelOverallExecutionBlueprint?>,
 ) : NadelOverallExecutionBlueprint {
     private val impl: NadelOverallExecutionBlueprint
         get() {

lib/src/main/java/graphql/nadel/engine/transform/NadelServiceTypeFilterTransform.kt

@@ -8,13 +8,15 @@ import graphql.nadel.engine.NadelExecutionContext
 import graphql.nadel.engine.NadelServiceExecutionContext
 import graphql.nadel.engine.blueprint.IntrospectionService
 import graphql.nadel.engine.blueprint.NadelOverallExecutionBlueprint
+import graphql.nadel.engine.blueprint.NadelOverallExecutionBlueprintMigrator
 import graphql.nadel.engine.transform.NadelServiceTypeFilterTransform.State
 import graphql.nadel.engine.transform.artificial.NadelAliasHelper
 import graphql.nadel.engine.transform.query.NadelQueryTransformer
 import graphql.nadel.engine.transform.result.NadelResultInstruction
 import graphql.nadel.engine.transform.result.json.JsonNodes
 import graphql.nadel.engine.util.resolveObjectTypes
 import graphql.nadel.engine.util.toBuilder
+import graphql.nadel.util.getLogger
 import graphql.normalized.ExecutableNormalizedField
 import graphql.normalized.ExecutableNormalizedField.newNormalizedField
 
@@ -63,6 +65,8 @@ import graphql.normalized.ExecutableNormalizedField.newNormalizedField
  * - service-types-are-completely-filtered.yml
  */
 class NadelServiceTypeFilterTransform : NadelTransform<State> {
+    private val logger = getLogger<NadelServiceTypeFilterTransform>()
+
     data class State(
         val aliasHelper: NadelAliasHelper,
         val typeNamesOwnedByService: Set<String>,
@@ -89,17 +93,49 @@ class NadelServiceTypeFilterTransform : NadelTransform<State> {
         }
 
         val typeNamesOwnedByService = executionBlueprint.getOverAllTypeNamesForService(service)
-        // Add underlying type names as well to handle combination of hydration and renames.
-        // Transforms are applied to hydration fields as well, and those fields always reference
-        // elements from the underlying schema
-        val underlyingTypeNamesOwnedByService = executionBlueprint.getUnderlyingTypeNamesForService(service)
+
         val fieldObjectTypeNamesOwnedByService = overallField.objectTypeNames
-            .filter {
-                // it is MUCH quicker to compare membership in 2 sets rather than
-                // concat 1 giant set and then check
-                it in typeNamesOwnedByService
-                    || it in underlyingTypeNamesOwnedByService
-                    || (executionContext.hints.sharedTypeRenames(service) && executionBlueprint.getUnderlyingTypeName(it) in underlyingTypeNamesOwnedByService)
+            .filter { objectTypeName ->
+                if (executionBlueprint is NadelOverallExecutionBlueprintMigrator && executionContext.hints.serviceTypenameShadowing.isShadowingEnabled()) {
+                    val oldDecision = isTypeOwnedByService(
+                        objectTypeName,
+                        executionContext,
+                        service,
+                        executionBlueprint.old,
+                    )
+
+                    try {
+                        val newDecision = executionBlueprint.new.value?.let { newBlueprint ->
+                            isTypeOwnedByService(
+                                objectTypeName,
+                                executionContext,
+                                service,
+                                newBlueprint,
+                            )
+                        }
+
+                        if (newDecision != null && oldDecision != newDecision) {
+                            executionContext.hints.serviceTypenameShadowing.onMismatch(
+                                oldDecision,
+                                newDecision,
+                                service,
+                                objectTypeName,
+                                overallField,
+                            )
+                        }
+                    } catch (e: Exception) {
+                        logger.error("Error shadowing service typename filter transform", e)
+                    }
+
+                    oldDecision
+                } else {
+                    isTypeOwnedByService(
+                        objectTypeName,
+                        executionContext,
+                        service,
+                        executionBlueprint,
+                    )
+                }
             }
 
         // All types are owned by service
@@ -108,7 +144,6 @@ class NadelServiceTypeFilterTransform : NadelTransform<State> {
             return null
         }
 
-
         return State(
             aliasHelper = NadelAliasHelper.forField(
                 tag = "type_filter",
@@ -120,6 +155,25 @@ class NadelServiceTypeFilterTransform : NadelTransform<State> {
         )
     }
 
+    private fun isTypeOwnedByService(
+        objectTypeName: String,
+        executionContext: NadelExecutionContext,
+        service: Service,
+        executionBlueprint: NadelOverallExecutionBlueprint,
+    ): Boolean {
+        val typeNamesOwnedByService = executionBlueprint.getOverAllTypeNamesForService(service)
+        // Add underlying type names as well to handle combination of hydration and renames.
+        // Transforms are applied to hydration fields as well, and those fields always reference
+        // elements from the underlying schema
+        val underlyingTypeNamesOwnedByService = executionBlueprint.getUnderlyingTypeNamesForService(service)
+
+        // it is MUCH quicker to compare membership in 2 sets rather than
+        // concat 1 giant set and then check
+        return objectTypeName in typeNamesOwnedByService
+            || objectTypeName in underlyingTypeNamesOwnedByService
+            || (executionContext.hints.sharedTypeRenames(service) && executionBlueprint.getUnderlyingTypeName(objectTypeName) in underlyingTypeNamesOwnedByService)
+    }
+
     override suspend fun transformField(
         executionContext: NadelExecutionContext,
         serviceExecutionContext: NadelServiceExecutionContext,

lib/src/main/java/graphql/nadel/hints/NadelServiceTypenameShadowingMismatchHint.kt

@@ -0,0 +1,33 @@
+package graphql.nadel.hints
+
+import graphql.nadel.Service
+import graphql.normalized.ExecutableNormalizedField
+
+interface NadelServiceTypenameShadowingHint {
+    fun isShadowingEnabled(): Boolean
+
+    fun onMismatch(
+        oldDecision: Boolean,
+        newDecision: Boolean,
+        service: Service,
+        objectTypeName: String,
+        field: ExecutableNormalizedField,
+    )
+
+    companion object {
+        internal val default = object : NadelServiceTypenameShadowingHint {
+            override fun isShadowingEnabled(): Boolean {
+                return false
+            }
+
+            override fun onMismatch(
+                oldDecision: Boolean,
+                newDecision: Boolean,
+                service: Service,
+                objectTypeName: String,
+                field: ExecutableNormalizedField,
+            ) {
+            }
+        }
+    }
+}