Data fetcher factory (#41)

* Update Junit dep to Junit5 * Add support for nested queries via custom datafetchers * Add example of custom datafetchers via spring beans * Mark lateinit field as nullable
ExpediaGroup · Oct 9, 2018 · 7111f0e · 7111f0e
1 parent f053b45
commit 7111f0e
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Showing 13 changed files with 215 additions and 29 deletions.
diff --git a/example/pom.xml b/example/pom.xml
@@ -60,15 +60,15 @@
 
     <properties>
         <java.version>1.8</java.version>
-        <kotlin.version>1.2.70</kotlin.version>
+        <kotlin.version>1.2.71</kotlin.version>
         <junit.version>4.12</junit.version>
         <graphiql.version>5.0.2</graphiql.version>
-        <graphql-kotlin.version>DEVELOPMENT</graphql-kotlin.version>
+        <graphql-kotlin.version>0.0.18-SNAPSHOT</graphql-kotlin.version>
         <graphql-servlet.version>6.1.2</graphql-servlet.version>
     </properties>
 
     <build>
-        <sourceDirectory>${project.basedir}/src/main/kotlin</sourceDirectory>
+        <sourceDirectory>src/main/kotlin</sourceDirectory>
         <plugins>
             <plugin>
                 <artifactId>kotlin-maven-plugin</artifactId>
@@ -140,5 +140,16 @@
                 </exclusion>
             </exclusions>
         </dependency>
+      <dependency>
+        <groupId>org.jetbrains.kotlin</groupId>
+        <artifactId>kotlin-stdlib-jdk8</artifactId>
+        <version>${kotlin.version}</version>
+      </dependency>
+      <dependency>
+        <groupId>org.jetbrains.kotlin</groupId>
+        <artifactId>kotlin-test</artifactId>
+        <version>${kotlin.version}</version>
+        <scope>test</scope>
+      </dependency>
     </dependencies>
 </project>
diff --git a/example/src/main/kotlin/com.expedia.graphql.sample/Application.kt b/example/src/main/kotlin/com.expedia.graphql.sample/Application.kt
@@ -2,6 +2,7 @@ package com.expedia.graphql.sample
 
 import com.expedia.graphql.TopLevelObjectDef
 import com.expedia.graphql.sample.context.MyGraphQLContextBuilder
+import com.expedia.graphql.sample.dataFetchers.SpringDataFetcherFactory
 import com.expedia.graphql.sample.extension.CustomSchemaGeneratorHooks
 import com.expedia.graphql.sample.mutation.Mutation
 import com.expedia.graphql.sample.query.Query
@@ -30,7 +31,11 @@ class Application {
     private val logger = LoggerFactory.getLogger(Application::class.java)
 
     @Bean
-    fun schemaConfig(): SchemaGeneratorConfig = SchemaGeneratorConfig(supportedPackages = "com.expedia", hooks = CustomSchemaGeneratorHooks())
+    fun schemaConfig(dataFetcherFactory: SpringDataFetcherFactory): SchemaGeneratorConfig = SchemaGeneratorConfig(
+            supportedPackages = "com.expedia",
+            hooks = CustomSchemaGeneratorHooks(),
+            dataFetcherFactory = dataFetcherFactory
+    )
 
     @Bean
     fun schema(

diff --git a/example/src/main/kotlin/com.expedia.graphql.sample/dataFetchers/SpringDataFetcherFactory.kt b/example/src/main/kotlin/com.expedia.graphql.sample/dataFetchers/SpringDataFetcherFactory.kt
@@ -0,0 +1,26 @@
+package com.expedia.graphql.sample.dataFetchers
+
+import com.expedia.graphql.schema.extensions.deepName
+import graphql.schema.DataFetcher
+import graphql.schema.DataFetcherFactory
+import graphql.schema.DataFetcherFactoryEnvironment
+import org.springframework.beans.factory.BeanFactory
+import org.springframework.beans.factory.BeanFactoryAware
+import org.springframework.stereotype.Component
+
+@Component
+class SpringDataFetcherFactory: DataFetcherFactory<Any>, BeanFactoryAware {
+    private lateinit var beanFactory: BeanFactory
+
+    override fun setBeanFactory(beanFactory: BeanFactory?) {
+        this.beanFactory = beanFactory!!
+    }
+
+    override fun get(environment: DataFetcherFactoryEnvironment?): DataFetcher<Any> {
+
+        //Strip out possible `Input` and `!` suffixes added to by the SchemaGenerator
+        val targetedTypeName = environment?.fieldDefinition?.type?.deepName?.removeSuffix("!")?.removeSuffix("Input")
+        return beanFactory.getBean("${targetedTypeName}DataFetcher") as DataFetcher<Any>
+    }
+
+}
diff --git a/example/src/main/kotlin/com.expedia.graphql.sample/query/NestedQueries.kt b/example/src/main/kotlin/com.expedia.graphql.sample/query/NestedQueries.kt
@@ -0,0 +1,50 @@
+package com.expedia.graphql.sample.query
+
+import com.fasterxml.jackson.annotation.JsonIgnore
+import graphql.schema.DataFetcher
+import graphql.schema.DataFetchingEnvironment
+import org.springframework.beans.factory.BeanFactory
+import org.springframework.beans.factory.BeanFactoryAware
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.beans.factory.getBean
+import org.springframework.context.annotation.Scope
+import org.springframework.stereotype.Component
+
+@Component
+class NestedQueries : Query {
+    fun findAnimal(context: String): NestedAnimal = NestedAnimal(1, "cat")
+}
+
+data class NestedAnimal(
+        val id: Int,
+        val type: String
+) {
+    @JsonIgnore
+    lateinit var details: NestedAnimalDetails
+}
+
+@Component
+@Scope("prototype")
+data class NestedAnimalDetails @Autowired(required = false) constructor(private val animalId: Int) {
+    fun veryDetailledFunction(): String = "Details($animalId)"
+}
+
+@Component("NestedAnimalDetailsDataFetcher")
+@Scope("prototype")
+class AnimalDetailsDataFetcher : DataFetcher<NestedAnimalDetails>, BeanFactoryAware {
+
+    private lateinit var beanFactory: BeanFactory
+
+    override fun setBeanFactory(beanFactory: BeanFactory) {
+        this.beanFactory = beanFactory
+    }
+
+    override fun get(environment: DataFetchingEnvironment?): NestedAnimalDetails {
+        val id = environment?.getSource<NestedAnimal>()?.id
+        if (id == null) {
+            throw Exception("Cannot retrieve animal details, the id is null")
+        } else {
+            return beanFactory.getBean(id)
+        }
+    }
+}
diff --git a/pom.xml b/pom.xml
@@ -75,6 +75,7 @@
         <kotlin-ktlint.version>0.29.0</kotlin-ktlint.version>
         <kotlin-detekt.version>1.0.0.RC8</kotlin-detekt.version>
         <junit.version>4.12</junit.version>
+        <mockk.version>1.8.9.kotlin13</mockk.version>
     </properties>
 
     <pluginRepositories>
@@ -209,14 +210,14 @@
         </dependency>
         <dependency>
             <groupId>org.jetbrains.kotlin</groupId>
-            <artifactId>kotlin-test-junit</artifactId>
+            <artifactId>kotlin-test-junit5</artifactId>
             <version>${kotlin.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>
-            <groupId>junit</groupId>
-            <artifactId>junit</artifactId>
-            <version>${junit.version}</version>
+            <groupId>io.mockk</groupId>
+            <artifactId>mockk</artifactId>
+            <version>${mockk.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>

diff --git a/src/main/kotlin/com/expedia/graphql/schema/SchemaGeneratorConfig.kt b/src/main/kotlin/com/expedia/graphql/schema/SchemaGeneratorConfig.kt
@@ -3,6 +3,7 @@ package com.expedia.graphql.schema
 import com.expedia.graphql.schema.generator.completableFutureResolver
 import com.expedia.graphql.schema.hooks.NoopSchemaGeneratorHooks
 import com.expedia.graphql.schema.hooks.SchemaGeneratorHooks
+import graphql.schema.DataFetcherFactory
 import kotlin.reflect.KType
 
 /**
@@ -13,5 +14,6 @@ data class SchemaGeneratorConfig(
     val topLevelQueryName: String = "TopLevelQuery",
     val topLevelMutationName: String = "TopLevelMutation",
     val hooks: SchemaGeneratorHooks = NoopSchemaGeneratorHooks(),
-    val monadResolver: (KType) -> KType = completableFutureResolver
+    val monadResolver: (KType) -> KType = completableFutureResolver,
+    val dataFetcherFactory: DataFetcherFactory<*>? = null
 )
diff --git a/src/main/kotlin/com/expedia/graphql/schema/generator/SchemaGenerator.kt b/src/main/kotlin/com/expedia/graphql/schema/generator/SchemaGenerator.kt
@@ -22,6 +22,7 @@ import graphql.schema.GraphQLInputObjectType
 import graphql.schema.GraphQLInputType
 import graphql.schema.GraphQLInterfaceType
 import graphql.schema.GraphQLList
+import graphql.schema.GraphQLNonNull
 import graphql.schema.GraphQLObjectType
 import graphql.schema.GraphQLOutputType
 import graphql.schema.GraphQLSchema
@@ -146,12 +147,30 @@ internal class SchemaGenerator(
         return builder.build()
     }
 
-    private fun property(prop: KProperty<*>): GraphQLFieldDefinition = GraphQLFieldDefinition.newFieldDefinition()
-        .description(prop.graphQLDescription())
-        .name(prop.name)
-        .type(graphQLTypeOf(prop.returnType) as GraphQLOutputType)
-        .deprecate(prop.getDeprecationReason())
-        .build()
+    private fun property(prop: KProperty<*>): GraphQLFieldDefinition {
+        val propertyType = graphQLTypeOf(prop.returnType) as GraphQLOutputType
+
+        val fieldBuilder = GraphQLFieldDefinition.newFieldDefinition()
+                .description(prop.graphQLDescription())
+                .name(prop.name)
+                .type(propertyType)
+                .deprecate(prop.getDeprecationReason())
+
+        return if (config.dataFetcherFactory != null && prop.isLateinit) {
+            updatePropertyFieldBuilder(propertyType, fieldBuilder)
+        } else {
+            fieldBuilder
+        }.build()
+    }
+
+    private fun updatePropertyFieldBuilder(propertyType: GraphQLOutputType, fieldBuilder: GraphQLFieldDefinition.Builder): GraphQLFieldDefinition.Builder {
+        val updatedFieldBuilder = if (propertyType is GraphQLNonNull) {
+            fieldBuilder.type(propertyType.wrappedType as GraphQLOutputType)
+        } else {
+            fieldBuilder
+        }
+        return updatedFieldBuilder.dataFetcherFactory(config.dataFetcherFactory)
+    }
 
     private fun argument(parameter: KParameter): GraphQLArgument {
         throwIfInterfaceIsNotAuthorized(parameter)

diff --git a/src/test/kotlin/com/expedia/graphql/schema/dataFetchers/CustomDataFetcherTests.kt b/src/test/kotlin/com/expedia/graphql/schema/dataFetchers/CustomDataFetcherTests.kt
@@ -0,0 +1,60 @@
+package com.expedia.graphql.schema.dataFetchers
+
+import com.expedia.graphql.TopLevelObjectDef
+import com.expedia.graphql.schema.SchemaGeneratorConfig
+import com.expedia.graphql.schema.extensions.deepName
+import com.expedia.graphql.toSchema
+import graphql.GraphQL
+import graphql.schema.DataFetcher
+import graphql.schema.DataFetcherFactory
+import graphql.schema.DataFetcherFactoryEnvironment
+import graphql.schema.DataFetchingEnvironment
+import org.junit.jupiter.api.Test
+import kotlin.test.assertEquals
+
+class CustomDataFetcherTests {
+    @Test
+    fun `Custom DataFetcher can be used on functions`() {
+        val config = SchemaGeneratorConfig(supportedPackages = "com.expedia", dataFetcherFactory = PetDataFetcherFactory())
+        val schema = toSchema(listOf(TopLevelObjectDef(AnimalQuery())), config = config)
+
+        val animalType = schema.getObjectType("Animal")
+        assertEquals("AnimalDetails", animalType.getFieldDefinition("details").type.deepName)
+
+        val graphQL = GraphQL.newGraphQL(schema).build()
+        val execute = graphQL.execute("{ findAnimal { id type details { specialId } } }")
+
+        val data = execute.getData<Map<String, Any>>()["findAnimal"] as? Map<*, *>
+        assertEquals(1, data?.get("id"))
+        assertEquals("cat", data?.get("type"))
+
+        val details = data?.get("details") as? Map<*, *>
+        assertEquals(11, details?.get("specialId"))
+    }
+}
+
+class AnimalQuery {
+    fun findAnimal(): Animal = Animal(1, "cat")
+}
+
+data class Animal(
+    val id: Int,
+    val type: String
+) {
+    lateinit var details: AnimalDetails
+}
+
+data class AnimalDetails(val specialId: Int)
+
+class PetDataFetcherFactory : DataFetcherFactory<Any> {
+    override fun get(environment: DataFetcherFactoryEnvironment?): DataFetcher<Any> = AnimalDetailsDataFetcher()
+}
+
+class AnimalDetailsDataFetcher : DataFetcher<Any> {
+
+    override fun get(environment: DataFetchingEnvironment?): AnimalDetails {
+        val animal = environment?.getSource<Animal>()
+        val specialId = animal?.id?.plus(10) ?: 0
+        return animal.let { AnimalDetails(specialId) }
+    }
+}
diff --git a/src/test/kotlin/com/expedia/graphql/schema/generator/DirectiveTests.kt b/src/test/kotlin/com/expedia/graphql/schema/generator/DirectiveTests.kt
@@ -8,7 +8,7 @@ import graphql.introspection.Introspection
 import graphql.schema.GraphQLInputObjectType
 import graphql.schema.GraphQLNonNull
 import graphql.schema.GraphQLObjectType
-import org.junit.Test
+import org.junit.jupiter.api.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertNotNull
 import kotlin.test.assertTrue

diff --git a/src/test/kotlin/com/expedia/graphql/schema/generator/KClassExtensionsTest.kt b/src/test/kotlin/com/expedia/graphql/schema/generator/KClassExtensionsTest.kt
@@ -1,7 +1,7 @@
 package com.expedia.graphql.schema.generator
 
 import com.expedia.graphql.schema.hooks.NoopSchemaGeneratorHooks
-import org.junit.Test
+import org.junit.jupiter.api.Test
 import kotlin.reflect.KFunction
 import kotlin.reflect.KProperty
 import kotlin.test.assertEquals

diff --git a/src/test/kotlin/com/expedia/graphql/schema/generator/PolymorphicTests.kt b/src/test/kotlin/com/expedia/graphql/schema/generator/PolymorphicTests.kt
@@ -5,7 +5,8 @@ import com.expedia.graphql.schema.exceptions.InvalidInputFieldTypeException
 import com.expedia.graphql.schema.testSchemaConfig
 import com.expedia.graphql.toSchema
 import graphql.schema.GraphQLUnionType
-import org.junit.Test
+import org.junit.jupiter.api.Assertions.assertThrows
+import org.junit.jupiter.api.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertNotNull
 import kotlin.test.assertTrue
@@ -40,14 +41,18 @@ class PolymorphicTests {
         assertEquals(implementationType.interfaces.first(), interfaceType)
     }
 
-    @Test(expected = InvalidInputFieldTypeException::class)
+    @Test
     fun `Interfaces cannot be used as input field types`() {
-        toSchema(listOf(TopLevelObjectDef(QueryWithUnAuthorizedInterfaceArgument())), config = testSchemaConfig)
+        assertThrows(InvalidInputFieldTypeException::class.java) {
+            toSchema(listOf(TopLevelObjectDef(QueryWithUnAuthorizedInterfaceArgument())), config = testSchemaConfig)
+        }
     }
 
-    @Test(expected = InvalidInputFieldTypeException::class)
+    @Test
     fun `Union cannot be used as input field types`() {
-        toSchema(listOf(TopLevelObjectDef(QueryWithUnAuthorizedUnionArgument())), config = testSchemaConfig)
+        assertThrows(InvalidInputFieldTypeException::class.java) {
+            toSchema(listOf(TopLevelObjectDef(QueryWithUnAuthorizedUnionArgument())), config = testSchemaConfig)
+        }
     }
 }
 

diff --git a/src/test/kotlin/com/expedia/graphql/schema/generator/SchemaGeneratorTest.kt b/src/test/kotlin/com/expedia/graphql/schema/generator/SchemaGeneratorTest.kt
@@ -10,6 +10,7 @@ import com.expedia.graphql.schema.testSchemaConfig
 import com.expedia.graphql.toSchema
 import graphql.GraphQL
 import graphql.schema.GraphQLObjectType
+import org.junit.jupiter.api.Assertions.assertThrows
 import java.net.CookieManager
 import kotlin.test.Test
 import kotlin.test.assertEquals
@@ -185,19 +186,25 @@ class SchemaGeneratorTest {
         assertEquals("something", resultWithPrivateParts.fieldDefinitions[0].name)
     }
 
-    @Test(expected = RuntimeException::class)
+    @Test
     fun `SchemaGenerator throws when encountering java stdlib`() {
-        toSchema(listOf(TopLevelObjectDef(QueryWithJavaClass())), config = testSchemaConfig)
+        assertThrows(RuntimeException::class.java) {
+            toSchema(listOf(TopLevelObjectDef(QueryWithJavaClass())), config = testSchemaConfig)
+        }
     }
 
-    @Test(expected = ConflictingTypesException::class)
+    @Test
     fun `SchemaGenerator throws when encountering conflicting types`() {
-        toSchema(queries = listOf(TopLevelObjectDef(QueryWithConflictingTypes())), config = testSchemaConfig)
+        assertThrows(ConflictingTypesException::class.java) {
+            toSchema(queries = listOf(TopLevelObjectDef(QueryWithConflictingTypes())), config = testSchemaConfig)
+        }
     }
 
-    @Test(expected = InvalidSchemaException::class)
+    @Test
     fun `SchemaGenerator should throw exception if no queries and no mutations are specified`() {
-        toSchema(emptyList(), emptyList(), config = testSchemaConfig)
+        assertThrows(InvalidSchemaException::class.java) {
+            toSchema(emptyList(), emptyList(), config = testSchemaConfig)
+        }
     }
 
     class QueryObject {

diff --git a/src/test/kotlin/com/expedia/graphql/schema/generator/TypesCacheTest.kt b/src/test/kotlin/com/expedia/graphql/schema/generator/TypesCacheTest.kt
@@ -2,7 +2,7 @@ package com.expedia.graphql.schema.generator
 
 import com.expedia.graphql.schema.models.KGraphQLType
 import graphql.schema.GraphQLType
-import org.junit.Test
+import org.junit.jupiter.api.Test
 import kotlin.reflect.full.starProjectedType
 import kotlin.test.assertFalse
 import kotlin.test.assertNotNull