feat(#389): allow templating for generated Java / Kotlin class names

Adds an optional `nameTemplate` input parameter to the plugin, allowing
customization of the generated Java / Kotlin class names.

The following template variables are supported:
- name - the original name of the class
- schemaType - the GraphQL schema type (Type, Input, Interface, Enum)

The default value for this new property is null. In this case the output
will be identical to the current one.

Examples:

Given an original class name `Person` and schema type `Type`:
 - null -> Person
 - "{name}GraphQL{schemaType}" -> PersonGraphQLType
 - "{name}GraphQL" -> PersonGraphQL
 - "{name}{schemaType}" -> PersonType

Author: BlasiusSecundus

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/CodeGen.kt

@@ -523,7 +523,8 @@ class CodeGenConfig(
     var implementSerializable: Boolean = false,
     var addGeneratedAnnotation: Boolean = false,
     var disableDatesInGeneratedAnnotation: Boolean = false,
-    var addDeprecatedAnnotation: Boolean = false
+    var addDeprecatedAnnotation: Boolean = false,
+    var nameTemplate: String? = null
 ) {
     val packageNameClient: String = "$packageName.$subPackageNameClient"
 

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/generators/java/DataTypeGenerator.kt

@@ -18,9 +18,13 @@
 
 package com.netflix.graphql.dgs.codegen.generators.java
 
-import com.netflix.graphql.dgs.codegen.*
+import com.netflix.graphql.dgs.codegen.CodeGenConfig
+import com.netflix.graphql.dgs.codegen.CodeGenResult
+import com.netflix.graphql.dgs.codegen.filterSkipped
+import com.netflix.graphql.dgs.codegen.generators.shared.CodeGeneratorUtils.templatedClassName
 import com.netflix.graphql.dgs.codegen.generators.shared.SiteTarget
 import com.netflix.graphql.dgs.codegen.generators.shared.applyDirectivesJava
+import com.netflix.graphql.dgs.codegen.shouldSkip
 import com.squareup.javapoet.ClassName
 import com.squareup.javapoet.CodeBlock
 import com.squareup.javapoet.FieldSpec
@@ -71,7 +75,7 @@ class DataTypeGenerator(config: CodeGenConfig, document: Document) : BaseDataTyp
 
         logger.info("Generating data type {}", definition.name)
 
-        val name = definition.name
+        val name = definition.templatedClassName(config.nameTemplate)
         val unionTypes = document.getDefinitionsOfType(UnionTypeDefinition::class.java).asSequence().filter { union ->
             union.memberTypes.asSequence().map { it as TypeName }.any { it.name == name }
         }.map { it.name }.toList()
@@ -168,7 +172,7 @@ class InputTypeGenerator(config: CodeGenConfig, document: Document) : BaseDataTy
 
         logger.info("Generating input type {}", definition.name)
 
-        val name = definition.name
+        val name = definition.templatedClassName(config.nameTemplate)
         val fieldDefinitions = definition.inputValueDefinitions.asSequence().map {
             val type = typeUtils.findReturnType(it.type)
             val defaultValue = it.defaultValue?.let { defVal ->

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/generators/java/EnumTypeGenerator.kt

@@ -20,6 +20,7 @@ package com.netflix.graphql.dgs.codegen.generators.java
 
 import com.netflix.graphql.dgs.codegen.CodeGenConfig
 import com.netflix.graphql.dgs.codegen.CodeGenResult
+import com.netflix.graphql.dgs.codegen.generators.shared.CodeGeneratorUtils.templatedClassName
 import com.netflix.graphql.dgs.codegen.generators.shared.SiteTarget
 import com.netflix.graphql.dgs.codegen.generators.shared.applyDirectivesJava
 import com.netflix.graphql.dgs.codegen.shouldSkip
@@ -44,7 +45,7 @@ class EnumTypeGenerator(private val config: CodeGenConfig) {
 
         val javaType =
             TypeSpec
-                .enumBuilder(definition.name)
+                .enumBuilder(definition.templatedClassName(config.nameTemplate))
                 .addModifiers(Modifier.PUBLIC)
                 .addOptionalGeneratedAnnotation(config)
 

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/generators/java/InterfaceGenerator.kt

@@ -22,12 +22,18 @@ import com.netflix.graphql.dgs.codegen.CodeGenConfig
 import com.netflix.graphql.dgs.codegen.CodeGenResult
 import com.netflix.graphql.dgs.codegen.filterSkipped
 import com.netflix.graphql.dgs.codegen.generators.shared.CodeGeneratorUtils.capitalized
+import com.netflix.graphql.dgs.codegen.generators.shared.CodeGeneratorUtils.templatedClassName
 import com.netflix.graphql.dgs.codegen.shouldSkip
 import com.squareup.javapoet.ClassName
 import com.squareup.javapoet.JavaFile
 import com.squareup.javapoet.MethodSpec
 import com.squareup.javapoet.TypeSpec
-import graphql.language.*
+import graphql.language.Document
+import graphql.language.FieldDefinition
+import graphql.language.InterfaceTypeDefinition
+import graphql.language.InterfaceTypeExtensionDefinition
+import graphql.language.ObjectTypeDefinition
+import graphql.language.TypeName
 import org.slf4j.Logger
 import org.slf4j.LoggerFactory
 import javax.lang.model.element.Modifier
@@ -51,7 +57,7 @@ class InterfaceGenerator(private val config: CodeGenConfig, private val document
         }
 
         logger.info("Generating type {}", definition.name)
-        val javaType = TypeSpec.interfaceBuilder(definition.name)
+        val javaType = TypeSpec.interfaceBuilder(definition.templatedClassName(config.nameTemplate))
             .addOptionalGeneratedAnnotation(config)
             .addModifiers(Modifier.PUBLIC)
 
@@ -91,11 +97,12 @@ class InterfaceGenerator(private val config: CodeGenConfig, private val document
 
         val implementations = document.getDefinitionsOfType(ObjectTypeDefinition::class.java).asSequence()
             .filter { node -> node.implements.any { it.isEqualTo(TypeName(definition.name)) } }
-            .map { node ->
-                typeUtils.findJavaInterfaceName(node.name, packageName)
+            .associate {
+                it.name to typeUtils
+                    .findJavaInterfaceName(it.templatedClassName(config.nameTemplate), packageName) as? ClassName
             }
-            .filterIsInstance<ClassName>()
-            .toList()
+            .mapNotNull { (name, className) -> className?.let { name to it } }
+            .toMap()
 
         // Add JsonSubType annotations only if there are no generated concrete types that implement the interface
         if (implementations.isNotEmpty() && config.generateDataTypes) {

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/generators/java/JavaPoetUtils.kt

@@ -95,16 +95,16 @@ fun disableJsonTypeInfoAnnotation(): AnnotationSpec {
  *  })
  *  ```
  */
-fun jsonSubTypeAnnotation(subTypes: Collection<ClassName>): AnnotationSpec {
+fun jsonSubTypeAnnotation(subTypes: Map<String, ClassName>): AnnotationSpec {
     val annotationSpec = AnnotationSpec.builder(JsonSubTypes::class.java)
 
     for (type in subTypes) {
         annotationSpec.addMember(
             "value",
             "\$L",
             AnnotationSpec.builder(JsonSubTypes.Type::class.java)
-                .addMember("value", "\$T.class", type)
-                .addMember("name", "\$S", type.simpleName())
+                .addMember("value", "\$T.class", type.value)
+                .addMember("name", "\$S", type.key)
                 .build()
         )
     }

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/generators/java/UnionTypeGenerator.kt

@@ -20,6 +20,7 @@ package com.netflix.graphql.dgs.codegen.generators.java
 
 import com.netflix.graphql.dgs.codegen.CodeGenConfig
 import com.netflix.graphql.dgs.codegen.CodeGenResult
+import com.netflix.graphql.dgs.codegen.generators.shared.CodeGeneratorUtils.templatedClassName
 import com.netflix.graphql.dgs.codegen.shouldSkip
 import com.squareup.javapoet.ClassName
 import com.squareup.javapoet.JavaFile
@@ -46,11 +47,12 @@ class UnionTypeGenerator(private val config: CodeGenConfig, private val document
 
         val memberTypes = definition.memberTypes.asSequence().plus(extensions.asSequence().flatMap { it.memberTypes })
             .filterIsInstance<TypeName>()
-            .map { member ->
-                typeUtils.findJavaInterfaceName(member.name, packageName)
+            .associate {
+                it.name to typeUtils
+                    .findJavaInterfaceName(it.templatedClassName(config.nameTemplate), packageName) as? ClassName
             }
-            .filterIsInstance<ClassName>()
-            .toList()
+            .mapNotNull { (name, className) -> className?.let { name to it } }
+            .toMap()
 
         if (memberTypes.isNotEmpty()) {
             javaType.addAnnotation(jsonTypeInfoAnnotation())

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/generators/kotlin/KotlinDataTypeGenerator.kt

@@ -22,6 +22,7 @@ import com.netflix.graphql.dgs.codegen.CodeGenConfig
 import com.netflix.graphql.dgs.codegen.CodeGenResult
 import com.netflix.graphql.dgs.codegen.filterSkipped
 import com.netflix.graphql.dgs.codegen.generators.java.InputTypeGenerator
+import com.netflix.graphql.dgs.codegen.generators.shared.CodeGeneratorUtils.templatedClassName
 import com.netflix.graphql.dgs.codegen.generators.shared.applyDirectivesKotlin
 import com.netflix.graphql.dgs.codegen.generators.shared.generateKotlinCode
 import com.netflix.graphql.dgs.codegen.shouldSkip
@@ -84,7 +85,7 @@ class KotlinDataTypeGenerator(config: CodeGenConfig, document: Document) :
                     )
                 }
         val interfaces = definition.implements + extensions.flatMap { it.implements }
-        return generate(definition.name, fields, interfaces, document, definition.description, definition.directives)
+        return generate(definition.templatedClassName(config.nameTemplate), fields, interfaces, document, definition.description, definition.directives)
     }
 }
 
@@ -139,7 +140,7 @@ class KotlinInputTypeGenerator(config: CodeGenConfig, document: Document) :
                 }
             )
         val interfaces = emptyList<Type<*>>()
-        return generate(definition.name, fields, interfaces, document, definition.description, definition.directives)
+        return generate(definition.templatedClassName(config.nameTemplate), fields, interfaces, document, definition.description, definition.directives)
     }
 }
 

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/generators/kotlin/KotlinEnumTypeGenerator.kt

@@ -22,6 +22,7 @@ import com.netflix.graphql.dgs.codegen.CodeGenConfig
 import com.netflix.graphql.dgs.codegen.CodeGenResult
 import com.netflix.graphql.dgs.codegen.generators.java.EnumTypeGenerator
 import com.netflix.graphql.dgs.codegen.generators.java.ReservedKeywordSanitizer
+import com.netflix.graphql.dgs.codegen.generators.shared.CodeGeneratorUtils.templatedClassName
 import com.netflix.graphql.dgs.codegen.generators.shared.applyDirectivesKotlin
 import com.netflix.graphql.dgs.codegen.shouldSkip
 import com.squareup.kotlinpoet.FileSpec
@@ -41,7 +42,7 @@ class KotlinEnumTypeGenerator(private val config: CodeGenConfig) {
 
         logger.info("Generating enum type ${definition.name}")
 
-        val kotlinType = TypeSpec.classBuilder(definition.name)
+        val kotlinType = TypeSpec.classBuilder(definition.templatedClassName(config.nameTemplate))
             .addOptionalGeneratedAnnotation(config)
             .addModifiers(KModifier.ENUM)
 

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/generators/kotlin/KotlinInterfaceTypeGenerator.kt

@@ -20,6 +20,7 @@ package com.netflix.graphql.dgs.codegen.generators.kotlin
 
 import com.netflix.graphql.dgs.codegen.CodeGenConfig
 import com.netflix.graphql.dgs.codegen.CodeGenResult
+import com.netflix.graphql.dgs.codegen.generators.shared.CodeGeneratorUtils.templatedClassName
 import com.netflix.graphql.dgs.codegen.shouldSkip
 import com.squareup.kotlinpoet.*
 import graphql.language.*
@@ -46,7 +47,7 @@ class KotlinInterfaceTypeGenerator(private val config: CodeGenConfig, private va
 
         logger.info("Generating type {}", definition.name)
 
-        val interfaceBuilder = TypeSpec.interfaceBuilder(definition.name)
+        val interfaceBuilder = TypeSpec.interfaceBuilder(definition.templatedClassName(config.nameTemplate))
             .addOptionalGeneratedAnnotation(config)
         if (definition.description != null) {
             interfaceBuilder.addKdoc("%L", definition.description.sanitizeKdoc())
@@ -85,11 +86,15 @@ class KotlinInterfaceTypeGenerator(private val config: CodeGenConfig, private va
             interfaceBuilder.addProperty(propertySpec.build())
         }
 
-        val implementations = document.getDefinitionsOfType(ObjectTypeDefinition::class.java).asSequence()
-            .filter { node -> node.implements.any { it.isEqualTo(TypeName(definition.name)) } }
-            .map { node -> typeUtils.findKtInterfaceName(node.name, packageName) }
-            .filterIsInstance<ClassName>()
-            .toList()
+        val implementations: Map<String, ClassName> =
+            document.getDefinitionsOfType(ObjectTypeDefinition::class.java).asSequence()
+                .filter { node -> node.implements.any { it.isEqualTo(TypeName(definition.name)) } }
+                .associate {
+                    it.name to typeUtils
+                        .findKtInterfaceName(it.templatedClassName(config.nameTemplate), packageName) as? ClassName
+                }
+                .mapNotNull { (name, className) -> className?.let { name to it } }
+                .toMap()
 
         if (implementations.isNotEmpty()) {
             interfaceBuilder.addAnnotation(jsonTypeInfoAnnotation())

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/generators/kotlin/KotlinPoetUtils.kt

@@ -97,15 +97,15 @@ fun disableJsonTypeInfoAnnotation(): AnnotationSpec {
  *  ])
  *  ```
  */
-fun jsonSubTypesAnnotation(subTypes: Collection<ClassName>): AnnotationSpec {
-    val subTypeAnnotations = subTypes.map { type ->
+fun jsonSubTypesAnnotation(subTypes: Map<String, ClassName>): AnnotationSpec {
+    val subTypeAnnotations = subTypes.map { (name, type) ->
         AnnotationSpec.builder(JsonSubTypes.Type::class)
             .addMember("value = %T::class", type)
-            .addMember("name = %S", type.simpleName)
+            .addMember("name = %S", name)
             .build()
     }
 
-    val formatString = subTypes.joinToString(
+    val formatString = subTypes.entries.joinToString(
         separator = ",\n",
         prefix = "value = [\n⇥",
         postfix = "⇤\n]"

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/generators/kotlin/KotlinUnionTypeGenerator.kt

@@ -20,6 +20,7 @@ package com.netflix.graphql.dgs.codegen.generators.kotlin
 
 import com.netflix.graphql.dgs.codegen.CodeGenConfig
 import com.netflix.graphql.dgs.codegen.CodeGenResult
+import com.netflix.graphql.dgs.codegen.generators.shared.CodeGeneratorUtils.templatedClassName
 import com.netflix.graphql.dgs.codegen.shouldSkip
 import com.squareup.kotlinpoet.ClassName
 import com.squareup.kotlinpoet.FileSpec
@@ -44,9 +45,12 @@ class KotlinUnionTypeGenerator(private val config: CodeGenConfig, document: Docu
 
         val memberTypes = definition.memberTypes.plus(extensions.flatMap { it.memberTypes }).asSequence()
             .filterIsInstance<TypeName>()
-            .map { member -> typeUtils.findKtInterfaceName(member.name, packageName) }
-            .filterIsInstance<ClassName>()
-            .toList()
+            .associate {
+                it.name to typeUtils
+                    .findKtInterfaceName(it.templatedClassName(config.nameTemplate), packageName) as? ClassName
+            }
+            .mapNotNull { (name, className) -> className?.let { name to it } }
+            .toMap()
 
         if (memberTypes.isNotEmpty()) {
             interfaceBuilder.addAnnotation(jsonTypeInfoAnnotation())

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/generators/kotlin2/GenerateKotlin2DataTypes.kt

@@ -33,6 +33,7 @@ import com.netflix.graphql.dgs.codegen.generators.kotlin.sanitizeKdoc
 import com.netflix.graphql.dgs.codegen.generators.kotlin.suppressInapplicableJvmNameAnnotation
 import com.netflix.graphql.dgs.codegen.generators.kotlin.toKtTypeName
 import com.netflix.graphql.dgs.codegen.generators.shared.CodeGeneratorUtils.capitalized
+import com.netflix.graphql.dgs.codegen.generators.shared.CodeGeneratorUtils.templatedClassName
 import com.netflix.graphql.dgs.codegen.generators.shared.SchemaExtensionsUtils.findTypeExtensions
 import com.netflix.graphql.dgs.codegen.generators.shared.excludeSchemaTypeExtension
 import com.netflix.graphql.dgs.codegen.shouldSkip
@@ -165,7 +166,7 @@ fun generateKotlin2DataTypes(
                 .build()
 
             // create the data class
-            val typeSpec = TypeSpec.classBuilder(typeDefinition.name)
+            val typeSpec = TypeSpec.classBuilder(typeDefinition.templatedClassName(config.nameTemplate))
                 .addOptionalGeneratedAnnotation(config)
                 // add docs if available
                 .apply {

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/generators/kotlin2/GenerateKotlin2EnumTypes.kt

@@ -22,6 +22,7 @@ import com.netflix.graphql.dgs.codegen.CodeGenConfig
 import com.netflix.graphql.dgs.codegen.generators.kotlin.addEnumConstants
 import com.netflix.graphql.dgs.codegen.generators.kotlin.addOptionalGeneratedAnnotation
 import com.netflix.graphql.dgs.codegen.generators.kotlin.sanitizeKdoc
+import com.netflix.graphql.dgs.codegen.generators.shared.CodeGeneratorUtils.templatedClassName
 import com.netflix.graphql.dgs.codegen.generators.shared.SchemaExtensionsUtils.findEnumExtensions
 import com.netflix.graphql.dgs.codegen.generators.shared.applyDirectivesKotlin
 import com.netflix.graphql.dgs.codegen.generators.shared.excludeSchemaTypeExtension
@@ -59,7 +60,7 @@ fun generateKotlin2EnumTypes(
                 .build()
 
             // create the enum class
-            val enumSpec = TypeSpec.classBuilder(enumDefinition.name)
+            val enumSpec = TypeSpec.classBuilder(enumDefinition.templatedClassName(config.nameTemplate))
                 .addOptionalGeneratedAnnotation(config)
                 .addModifiers(KModifier.ENUM)
                 // add docs if available

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/generators/kotlin2/GenerateKotlin2InputTypes.kt

@@ -26,6 +26,7 @@ import com.netflix.graphql.dgs.codegen.generators.kotlin.KotlinTypeUtils
 import com.netflix.graphql.dgs.codegen.generators.kotlin.ReservedKeywordFilter
 import com.netflix.graphql.dgs.codegen.generators.kotlin.addOptionalGeneratedAnnotation
 import com.netflix.graphql.dgs.codegen.generators.kotlin.sanitizeKdoc
+import com.netflix.graphql.dgs.codegen.generators.shared.CodeGeneratorUtils.templatedClassName
 import com.netflix.graphql.dgs.codegen.generators.shared.SchemaExtensionsUtils.findInputExtensions
 import com.netflix.graphql.dgs.codegen.generators.shared.excludeSchemaTypeExtension
 import com.netflix.graphql.dgs.codegen.generators.shared.generateKotlinCode
@@ -71,7 +72,7 @@ fun generateKotlin2InputTypes(
             val typeName = ClassName(config.packageNameTypes, inputDefinition.name)
 
             // create the input class
-            val typeSpec = TypeSpec.classBuilder(typeName)
+            val typeSpec = TypeSpec.classBuilder(inputDefinition.templatedClassName(config.nameTemplate))
                 .addOptionalGeneratedAnnotation(config)
                 // add docs if available
                 .apply {

graphql-dgs-codegen-core/src/main/kotlin/com/netflix/graphql/dgs/codegen/generators/kotlin2/GenerateKotlin2Interfaces.kt

@@ -26,6 +26,7 @@ import com.netflix.graphql.dgs.codegen.generators.kotlin.jsonTypeInfoAnnotation
 import com.netflix.graphql.dgs.codegen.generators.kotlin.jvmNameAnnotation
 import com.netflix.graphql.dgs.codegen.generators.kotlin.sanitizeKdoc
 import com.netflix.graphql.dgs.codegen.generators.kotlin.suppressInapplicableJvmNameAnnotation
+import com.netflix.graphql.dgs.codegen.generators.shared.CodeGeneratorUtils.templatedClassName
 import com.netflix.graphql.dgs.codegen.generators.shared.SchemaExtensionsUtils.findInterfaceExtensions
 import com.netflix.graphql.dgs.codegen.generators.shared.SchemaExtensionsUtils.findUnionExtensions
 import com.netflix.graphql.dgs.codegen.generators.shared.excludeSchemaTypeExtension
@@ -64,7 +65,7 @@ fun generateKotlin2Interfaces(
             val implementations = document
                 .getDefinitionsOfType(ObjectTypeDefinition::class.java)
                 .filter { node -> node.implements.any { it.isEqualTo(TypeName(interfaceDefinition.name)) } }
-                .map { node -> ClassName(config.packageNameTypes, node.name) }
+                .associate { it.name to ClassName(config.packageNameTypes, it.templatedClassName(config.nameTemplate)) }
 
             // get all interfaces that this interface implements
             val implementedInterfaces = typeLookup.implementedInterfaces(interfaceDefinition)
@@ -82,7 +83,7 @@ fun generateKotlin2Interfaces(
             val overrideFields = typeLookup.overrideFields(implementedInterfaces)
 
             // create the interface
-            val interfaceSpec = TypeSpec.interfaceBuilder(interfaceDefinition.name)
+            val interfaceSpec = TypeSpec.interfaceBuilder(interfaceDefinition.templatedClassName(config.nameTemplate))
                 .addOptionalGeneratedAnnotation(config)
                 .addModifiers(KModifier.SEALED)
                 // add docs if available
@@ -144,7 +145,7 @@ fun generateKotlin2Interfaces(
             val implementations = unionDefinition.memberTypes
                 .plus(extensionTypes.flatMap { it.memberTypes })
                 .filterIsInstance<NamedNode<*>>()
-                .map { node -> ClassName(config.packageNameTypes, node.name) }
+                .associate { it.name to ClassName(config.packageNameTypes, it.templatedClassName(config.nameTemplate)) }
 
             // create the interface
             val interfaceSpec = TypeSpec.interfaceBuilder(unionDefinition.name)