Implement SchemaGenerator as closeable

Author: Shane Myrick

graphql-kotlin-federation/src/main/kotlin/com/expediagroup/graphql/federation/toFederatedSchema.kt

@@ -38,5 +38,7 @@ fun toFederatedSchema(
     subscriptions: List<TopLevelObject> = emptyList()
 ): GraphQLSchema {
     val generator = FederatedSchemaGenerator(config)
-    return generator.generateSchema(queries, mutations, subscriptions)
+    return generator.use {
+        it.generateSchema(queries, mutations, subscriptions)
+    }
 }

graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/SchemaGenerator.kt

@@ -28,6 +28,7 @@ import graphql.schema.GraphQLCodeRegistry
 import graphql.schema.GraphQLDirective
 import graphql.schema.GraphQLSchema
 import graphql.schema.GraphQLType
+import java.io.Closeable
 import java.util.concurrent.ConcurrentHashMap
 import kotlin.reflect.KClass
 import kotlin.reflect.KType
@@ -39,7 +40,7 @@ import kotlin.reflect.full.createType
  * This class maintains the state of the schema while generation is taking place. It is passed into the internal functions
  * so they can use the cache and add additional types and directives into the schema as they parse the Kotlin code.
  */
-open class SchemaGenerator(internal val config: SchemaGeneratorConfig) {
+open class SchemaGenerator(internal val config: SchemaGeneratorConfig) : Closeable {
 
     internal val additionalTypes = mutableSetOf<KType>()
     internal val classScanner = ClassScanner(config.supportedPackages)
@@ -56,20 +57,17 @@ open class SchemaGenerator(internal val config: SchemaGeneratorConfig) {
         subscriptions: List<TopLevelObject> = emptyList(),
         additionalTypes: Set<KType> = emptySet()
     ): GraphQLSchema {
-
         this.additionalTypes.addAll(additionalTypes)
+
         val builder = GraphQLSchema.newSchema()
         builder.query(generateQueries(this, queries))
         builder.mutation(generateMutations(this, mutations))
         builder.subscription(generateSubscriptions(this, subscriptions))
         builder.additionalTypes(generateAdditionalTypes())
         builder.additionalDirectives(directives.values.toSet())
         builder.codeRegistry(codeRegistry.build())
-        val schema = config.hooks.willBuildSchema(builder).build()
 
-        cleanUpResources()
-
-        return schema
+        return config.hooks.willBuildSchema(builder).build()
     }
 
     /**
@@ -101,9 +99,19 @@ open class SchemaGenerator(internal val config: SchemaGeneratorConfig) {
         return graphqlTypes.toSet()
     }
 
-    private fun cleanUpResources() {
-        additionalTypes.clear()
+    /**
+     * Clear the generator type cache, reflection scan, additional types,
+     * and the saved directives. You may want call this after you have
+     * called [generateSchema] and performed some other actions which is why
+     * we have a separate method to explicitly clear.
+     *
+     * If you use the built in [com.expediagroup.graphql.toSchema], we will handle
+     * clean up of resources for you.
+     */
+    override fun close() {
+        classScanner.close()
         cache.clear()
+        additionalTypes.clear()
         directives.clear()
     }
 }

graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/state/ClassScanner.kt

@@ -19,10 +19,11 @@ package com.expediagroup.graphql.generator.state
 import io.github.classgraph.ClassGraph
 import io.github.classgraph.ClassInfo
 import io.github.classgraph.ClassInfoList
+import java.io.Closeable
 import kotlin.reflect.KClass
 import kotlin.reflect.jvm.jvmName
 
-internal class ClassScanner(supportedPackages: List<String>) {
+internal class ClassScanner(supportedPackages: List<String>) : Closeable {
 
     @Suppress("Detekt.SpreadOperator")
     private val scanResult = ClassGraph()
@@ -39,6 +40,8 @@ internal class ClassScanner(supportedPackages: List<String>) {
             .filterNot { it.isAbstract }
     }
 
+    override fun close() = scanResult.close()
+
     fun getClassesWithAnnotation(annotation: KClass<*>) = scanResult.getClassesWithAnnotation(annotation.jvmName).map { it.loadClass().kotlin }
 
     @Suppress("Detekt.SwallowedException")

graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/toSchema.kt

@@ -38,5 +38,7 @@ fun toSchema(
     subscriptions: List<TopLevelObject> = emptyList()
 ): GraphQLSchema {
     val generator = SchemaGenerator(config)
-    return generator.generateSchema(queries, mutations, subscriptions)
+    return generator.use {
+        it.generateSchema(queries, mutations, subscriptions)
+    }
 }

graphql-kotlin-schema-generator/src/test/kotlin/com/expediagroup/graphql/generator/PolymorphicTests.kt

@@ -20,6 +20,7 @@ import com.expediagroup.graphql.TopLevelObject
 import com.expediagroup.graphql.annotations.GraphQLIgnore
 import com.expediagroup.graphql.annotations.GraphQLName
 import com.expediagroup.graphql.exceptions.InvalidInputFieldTypeException
+import com.expediagroup.graphql.createNewTestGenerator
 import com.expediagroup.graphql.testGenerator
 import graphql.TypeResolutionEnvironment
 import graphql.schema.GraphQLInterfaceType
@@ -96,7 +97,7 @@ class PolymorphicTests {
 
     @Test
     fun `Interfaces can declare properties of their own type`() {
-        val schema = testGenerator.generateSchema(queries = listOf(TopLevelObject(QueryWithRecursiveType())))
+        val schema = createNewTestGenerator().generateSchema(queries = listOf(TopLevelObject(QueryWithRecursiveType())))
 
         val personType = schema.getType("Person")
         assertNotNull(personType)
@@ -117,7 +118,7 @@ class PolymorphicTests {
 
     @Test
     fun `Interface types can be correctly resolved`() {
-        val schema = testGenerator.generateSchema(queries = listOf(TopLevelObject(QueryWithRenamedAbstracts())))
+        val schema = createNewTestGenerator().generateSchema(queries = listOf(TopLevelObject(QueryWithRenamedAbstracts())))
 
         val cakeInterface = schema.getType("Cake") as? GraphQLInterfaceType
         assertNotNull(cakeInterface)
@@ -162,7 +163,7 @@ class PolymorphicTests {
 
     @Test
     fun `Ignored interface properties should not appear in the subtype`() {
-        val schema = testGenerator.generateSchema(queries = listOf(TopLevelObject(QueryWithIgnoredInfo())))
+        val schema = createNewTestGenerator().generateSchema(queries = listOf(TopLevelObject(QueryWithIgnoredInfo())))
         val service = schema.getType("Service") as? GraphQLInterfaceType
         assertNotNull(service)
         val interfaceIgnoredField = service.getFieldDefinition("shouldNotBeInTheSchema")

graphql-kotlin-schema-generator/src/test/kotlin/com/expediagroup/graphql/testSchemaConfig.kt

@@ -23,10 +23,12 @@ import com.expediagroup.graphql.hooks.SchemaGeneratorHooks
 import io.mockk.every
 import io.mockk.spyk
 
-val defaultSupportedPackages = listOf("com.expediagroup")
+val defaultSupportedPackages = listOf("com.expediagroup.graphql")
 val testSchemaConfig = SchemaGeneratorConfig(defaultSupportedPackages)
 val testGenerator = SchemaGenerator(testSchemaConfig)
 
+fun createNewTestGenerator() = SchemaGenerator(testSchemaConfig)
+
 fun getTestSchemaConfigWithHooks(hooks: SchemaGeneratorHooks) = SchemaGeneratorConfig(defaultSupportedPackages, hooks = hooks)
 
 fun getTestSchemaConfigWithMockedDirectives() = getTestSchemaConfigWithHooks(hooks = object : SchemaGeneratorHooks {