[plugin] fix generate client MOJO converter parameter (#713)

In order for Maven to recognize complex objects all their fields need to be annoated with `@Parameter` annotation.

Additonal changes
- add debug messages for logging generate client task/mojo configuration
- update integration tests to validate custom scalar logic
- update Gradle task `converters` parameter to match Maven MOJO parameter

Author: dariuszkuc

docs/plugins/gradle-plugin.md

@@ -40,7 +40,7 @@ graphql {
   // Boolean flag indicating whether or not selection of deprecated fields is allowed.
   allowDeprecatedFields = false
   // Custom GraphQL scalar to converter mapping containing information about corresponding Java type and converter that should be used to serialize/deserialize values.
-  scalarConverters.put("UUID", ScalarConverterMapping("java.util.UUID", "com.example.UUIDScalarConverter"))
+  converters.put("UUID", ScalarConverterMapping("java.util.UUID", "com.example.UUIDScalarConverter"))
 }
 ```
 
@@ -73,10 +73,10 @@ file and are placed under specified `packageName`.
 | Property | Type | Required | Description |
 | -------- | ---- | -------- | ----------- |
 | `allowDeprecatedFields` | Boolean | | Boolean flag indicating whether selection of deprecated fields is allowed or not.<br/>**Default value is:** `false`.<br/>**Command line property is**: `allowDeprecatedFields`. |
+| `converters` | Map<String, ScalarConverter> | | Custom GraphQL scalar to converter mapping containing information about corresponding Java type and converter that should be used to serialize/deserialize values. |
 | `packageName` | String | yes | Target package name for generated code.<br/>**Command line property is**: `packageName`. |
 | `queryFiles` | FileCollection | | List of query files to be processed. Instead of a list of files to be processed you can specify `queryFileDirectory` directory instead. If this property is specified it will take precedence over the corresponding directory property. |
 | `queryFileDirectory` | String | | Directory file containing GraphQL queries. Instead of specifying a directory you can also specify list of query file by using `queryFiles` property instead.<br/>**Default value is:** `src/main/resources`.<br/>**Command line property is**: `queryFileDirectory`. |
-| `scalarConverters` | Map<String, ScalarConverter> | | Custom GraphQL scalar to converter mapping containing information about corresponding Java type and converter that should be used to serialize/deserialize values. |
 | `schemaFile` | File | `schemaFileName` or `schemaFile` has to be provided | GraphQL schema file that will be used to generate client code. |
 | `schemaFileName` | String | `schemaFileName` or `schemaFile` has to be provided | Path to GraphQL schema file that will be used to generate client code.<br/>**Command line property is**: `schemaFileName`. |
 
@@ -203,7 +203,7 @@ import com.expediagroup.graphql.plugin.gradle.tasks.GraphQLGenerateClientTask
 val graphqlGenerateClient by tasks.getting(GraphQLGenerateClientTask::class) {
   packageName.set("com.example.generated")
   schemaFileName.set("mySchema.graphql")
-  scalarConverters.put("UUID", ScalarConverterMapping("java.util.UUID", "com.example.UUIDScalarConverter"))
+  converters.put("UUID", ScalarConverterMapping("java.util.UUID", "com.example.UUIDScalarConverter"))
 }
 ```
 

plugins/graphql-kotlin-gradle-plugin/README.md

@@ -54,10 +54,10 @@ file and are placed under specified `packageName`.
 | Property | Type | Required | Description |
 | -------- | ---- | -------- | ----------- |
 | `allowDeprecatedFields` | Boolean | | Boolean flag indicating whether selection of deprecated fields is allowed or not.<br/>**Default value is:** `false`.<br/>**Command line property is**: `allowDeprecatedFields`. |
+| `converters` | Map<String, ScalarConverter> | | Custom GraphQL scalar to converter mapping containing information about corresponding Java type and converter that should be used to serialize/deserialize values. |
 | `packageName` | String | yes | Target package name for generated code.<br/>**Command line property is**: `packageName`. |
 | `queryFiles` | FileCollection | | List of query files to be processed. Instead of a list of files to be processed you can specify `queryFileDirectory` directory instead. If this property is specified it will take precedence over the corresponding directory property. |
 | `queryFileDirectory` | String | | Directory file containing GraphQL queries. Instead of specifying a directory you can also specify list of query file by using `queryFiles` property instead.<br/>**Default value is:** `src/main/resources`.<br/>**Command line property is**: `queryFileDirectory`. |
-| `scalarConverters` | Map<String, ScalarConverter> | | Custom GraphQL scalar to converter mapping containing information about corresponding Java type and converter that should be used to serialize/deserialize values. |
 | `schemaFile` | File | `schemaFileName` or `schemaFile` has to be provided | GraphQL schema file that will be used to generate client code. |
 | `schemaFileName` | String | `schemaFileName` or `schemaFile` has to be provided | Path to GraphQL schema file that will be used to generate client code.<br/>**Command line property is**: `schemaFileName`. |
 

plugins/graphql-kotlin-gradle-plugin/src/main/kotlin/com/expediagroup/graphql/plugin/gradle/GraphQLGradlePlugin.kt

@@ -59,7 +59,7 @@ class GraphQLGradlePlugin : Plugin<Project> {
                 val generateClientTask = project.tasks.named(GENERATE_CLIENT_TASK_NAME, GraphQLGenerateClientTask::class.java).get()
                 generateClientTask.packageName.convention(project.provider { extension.packageName })
                 generateClientTask.allowDeprecatedFields.convention(project.provider { extension.allowDeprecatedFields })
-                generateClientTask.scalarConverters.convention(extension.scalarConverters)
+                generateClientTask.converters.convention(extension.scalarConverters)
                 generateClientTask.queryFiles.setFrom(extension.queryFiles.from)
 
                 if (extension.endpoint != null) {

plugins/graphql-kotlin-gradle-plugin/src/main/kotlin/com/expediagroup/graphql/plugin/gradle/tasks/GraphQLGenerateClientTask.kt

@@ -89,12 +89,12 @@ open class GraphQLGenerateClientTask : DefaultTask() {
      * serialize/deserialize values.
      *
      * ```kotlin
-     * scalarConverters.put("UUID", ScalarConverterMapping("java.util.UUID", "com.expediagroup.graphql.examples.client.UUIDScalarConverter"))
+     * converters.put("UUID", ScalarConverterMapping("java.util.UUID", "com.expediagroup.graphql.examples.client.UUIDScalarConverter"))
      * ```
      */
     @Input
     @Optional
-    val scalarConverters: MapProperty<String, ScalarConverterMapping> = project.objects.mapProperty(String::class.java, ScalarConverterMapping::class.java)
+    val converters: MapProperty<String, ScalarConverterMapping> = project.objects.mapProperty(String::class.java, ScalarConverterMapping::class.java)
 
     /**
      * Directory containing GraphQL queries, defaults to `src/main/resources`.
@@ -123,12 +123,14 @@ open class GraphQLGenerateClientTask : DefaultTask() {
 
         queryFileDirectory.convention("${project.projectDir}/src/main/resources")
         allowDeprecatedFields.convention(false)
-        scalarConverters.convention(emptyMap())
+        converters.convention(emptyMap())
     }
 
     @Suppress("EXPERIMENTAL_API_USAGE")
     @TaskAction
     fun generateGraphQLClientAction() {
+        logger.debug("generating GraphQL client")
+
         val graphQLSchema = when {
             schemaFile.isPresent -> schemaFile.get().asFile
             schemaFileName.isPresent -> File(schemaFileName.get())
@@ -155,12 +157,34 @@ open class GraphQLGenerateClientTask : DefaultTask() {
         if (!targetDirectory.isDirectory && !targetDirectory.mkdirs()) {
             throw RuntimeException("failed to generate generated source directory")
         }
+
+        logConfiguration(graphQLSchema, targetQueryFiles)
         val config = GraphQLClientGeneratorConfig(
             packageName = targetPackage,
             allowDeprecated = allowDeprecatedFields.get(),
-            scalarTypeToConverterMapping = scalarConverters.get())
+            scalarTypeToConverterMapping = converters.get())
         generateClient(config, graphQLSchema, targetQueryFiles).forEach {
             it.writeTo(targetDirectory)
         }
+        logger.debug("successfully generated GraphQL HTTP client")
+    }
+
+    private fun logConfiguration(schema: File, queryFiles: List<File>) {
+        logger.debug("GraphQL Client generator configuration:")
+        logger.debug("  schema file = ${schema.path}")
+        logger.debug("  queries")
+        queryFiles.forEach {
+            logger.debug("    - ${it.name}")
+        }
+        logger.debug("  packageName = $packageName")
+        logger.debug("  allowDeprecatedFields = $allowDeprecatedFields")
+        logger.debug("  converters")
+        converters.get().entries.forEach { (customScalar, converterInfo) ->
+            logger.debug("    - custom scalar = $customScalar")
+            logger.debug("      |- type = ${converterInfo.type}")
+            logger.debug("      |- converter = ${converterInfo.converter}")
+        }
+        logger.debug("")
+        logger.debug("-- end GraphQL Client generator configuration --")
     }
 }

plugins/graphql-kotlin-gradle-plugin/src/test/kotlin/com/expediagroup/graphql/plugin/gradle/GraphQLGradlePluginIT.kt

@@ -136,6 +136,7 @@ class GraphQLGradlePluginIT {
         val kotlinVersion = System.getProperty("kotlinVersion") ?: "1.3.71"
         val buildFileContents = """
             import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
+            import com.expediagroup.graphql.plugin.generator.ScalarConverterMapping
             import com.expediagroup.graphql.plugin.gradle.tasks.GraphQLGenerateClientTask
             import com.expediagroup.graphql.plugin.gradle.tasks.GraphQLIntrospectSchemaTask
 
@@ -160,6 +161,7 @@ class GraphQLGradlePluginIT {
             val graphqlGenerateClient by tasks.getting(GraphQLGenerateClientTask::class) {
               packageName.set("com.expediagroup.graphql.generated")
               schemaFile.set(graphqlIntrospectSchema.outputFile)
+              converters.put("UUID", ScalarConverterMapping("java.util.UUID", "com.example.UUIDScalarConverter"))
               dependsOn("graphqlIntrospectSchema")
             }
 
@@ -189,26 +191,40 @@ class GraphQLGradlePluginIT {
                 package com.example
 
                 import com.expediagroup.graphql.client.GraphQLClient
+                import com.expediagroup.graphql.client.converter.ScalarConverter
                 import com.expediagroup.graphql.generated.JUnitQuery
                 import kotlinx.coroutines.runBlocking
                 import java.net.URL
+                import java.util.UUID
 
                 fun main() {
                     val client = GraphQLClient(URL("${wireMockServer.baseUrl()}/graphql"))
                     val query = JUnitQuery(client)
 
                     val variables = JUnitQuery.Variables(JUnitQuery.SimpleArgumentInput(min = null, max = null, newName = "blah"))
                     runBlocking {
-                        val result = query.execute(variables)
-                        val data = result.data
+                        val response = query.execute(variables = variables)
+                        val data = response.data
                         assert(data != null)
+                        val scalarResult = data?.scalarQuery
+                        assert(scalarResult is JUnitQuery.ScalarWrapper)
+                        assert(scalarResult != null)
+                        assert(scalarResult?.count is Int)
+                        assert(scalarResult?.custom is JUnitQuery.UUID)
                         assert(JUnitQuery.CustomEnum.ONE == data?.enumQuery)
-                        assert(data?.interfaceQuery is JUnitQuery.SecondInterfaceImplementation)
-                        assert(data?.unionQuery is JUnitQuery.BasicObject)
-                        assert(result.errors == null)
-                        assert(result.extensions == null)
+                        val interfaceResult = data?.interfaceQuery
+                        assert(interfaceResult is JUnitQuery.SecondInterfaceImplementation)
+                        val unionResult = data?.unionQuery
+                        assert(unionResult is JUnitQuery.BasicObject)
+                        assert(response.errors == null)
+                        assert(response.extensions == null)
                     }
                 }
+
+                class UUIDScalarConverter : ScalarConverter<UUID> {
+                    override fun toScalar(rawValue: String): UUID = UUID.fromString(rawValue)
+                    override fun toJson(value: UUID): String = value.toString()
+                }
             """.trimIndent())
 
         val codeGenerationResult = GradleRunner.create()

plugins/graphql-kotlin-maven-plugin/src/integration/complete-setup/pom.xml

@@ -98,6 +98,16 @@
                         <configuration>
                             <packageName>com.expediagroup.graphql.plugin.generated</packageName>
                             <schemaFile>${project.build.directory}/schema.graphql</schemaFile>
+                            <converters>
+                                <!-- custom scalar UUID type -->
+                                <UUID>
+                                    <!-- fully qualified Java class name of a custom scalar type -->
+                                    <type>java.util.UUID</type>
+                                    <!-- fully qualified Java class name of a custom com.expediagroup.graphql.client.converter.ScalarConverter
+                                       used to convert to/from raw JSON and scalar type -->
+                                    <converter>com.example.UUIDScalarConverter</converter>
+                                </UUID>
+                            </converters>
                         </configuration>
                     </execution>
                 </executions>

plugins/graphql-kotlin-maven-plugin/src/integration/complete-setup/src/main/kotlin/com/example/UUIDScalarConverter.kt

@@ -0,0 +1,9 @@
+package com.example
+
+import com.expediagroup.graphql.client.converter.ScalarConverter
+import java.util.UUID
+
+class UUIDScalarConverter : ScalarConverter<UUID> {
+    override fun toScalar(rawValue: String): UUID = UUID.fromString(rawValue)
+    override fun toJson(value: UUID): String = value.toString()
+}

plugins/graphql-kotlin-maven-plugin/src/integration/complete-setup/src/test/kotlin/com/expediagroup/graphql/plugin/maven/GraphQLMavenPluginTest.kt

@@ -57,6 +57,11 @@ class GraphQLMavenPluginTest {
                 assertTrue(response.errors == null)
                 val data = response.data
                 assertNotNull(data)
+                val scalarResult = data?.scalarQuery
+                assertTrue(scalarResult is ExampleQuery.ScalarWrapper)
+                assertNotNull(scalarResult)
+                assertTrue(scalarResult?.count is Int)
+                assertTrue(scalarResult?.custom is ExampleQuery.UUID)
                 assertEquals(ExampleQuery.CustomEnum.ONE, data?.enumQuery)
                 val interfaceResult = data?.interfaceQuery
                 assertTrue(interfaceResult is ExampleQuery.SecondInterfaceImplementation)

plugins/graphql-kotlin-maven-plugin/src/main/kotlin/com/expediagroup/graphql/plugin/maven/GenerateClientMojo.kt

@@ -74,7 +74,7 @@ class GenerateClientMojo : AbstractMojo() {
      * ```
      */
     @Parameter(name = "converters")
-    private var converters: Map<String, ScalarConverter> = emptyMap()
+    private var converters: Map<String, ScalarConverter> = mutableMapOf()
 
     /**
      * Directory file containing GraphQL queries, defaults to `src/main/resources`. Instead of specifying a directory you can
@@ -107,9 +107,7 @@ class GenerateClientMojo : AbstractMojo() {
 
         val targetQueryFiles: List<File> = when {
             ::queryFiles.isInitialized -> queryFiles
-            else -> queryFileDirectory
-                .listFiles { file -> file.extension == "graphql" }
-                ?.toList() ?: throw RuntimeException("exception while looking up the query files")
+            else -> queryFileDirectory.listFiles { file -> file.extension == "graphql" }?.toList() ?: throw RuntimeException("exception while looking up the query files")
         }
         if (targetQueryFiles.isEmpty()) {
             throw RuntimeException("no query files specified")
@@ -118,6 +116,8 @@ class GenerateClientMojo : AbstractMojo() {
         if (!outputDirectory.isDirectory && !outputDirectory.mkdirs()) {
             throw RuntimeException("failed to generate generated source directory")
         }
+
+        logConfiguration(targetQueryFiles)
         val config = GraphQLClientGeneratorConfig(
             packageName = packageName,
             allowDeprecated = allowDeprecatedFields,
@@ -130,6 +130,25 @@ class GenerateClientMojo : AbstractMojo() {
         project.addCompileSourceRoot(outputDirectory.path)
         log.debug("successfully generated GraphQL HTTP client")
     }
+
+    private fun logConfiguration(queryFiles: List<File>) {
+        log.debug("GraphQL Client generator configuration:")
+        log.debug("  schema file = ${schemaFile.path}")
+        log.debug("  queries")
+        queryFiles.forEach {
+            log.debug("    - ${it.name}")
+        }
+        log.debug("  packageName = $packageName")
+        log.debug("  allowDeprecatedFields = $allowDeprecatedFields")
+        log.debug("  converters")
+        converters.entries.forEach { (customScalar, converterInfo) ->
+            log.debug("    - custom scalar = $customScalar")
+            log.debug("      |- type = ${converterInfo.type}")
+            log.debug("      |- converter = ${converterInfo.converter}")
+        }
+        log.debug("")
+        log.debug("-- end GraphQL Client generator configuration --")
+    }
 }
 
 /**
@@ -140,9 +159,12 @@ class GenerateClientMojo : AbstractMojo() {
  *
  * @see [Guide to Configuring Plug-ins](https://maven.apache.org/guides/mini/guide-configuring-plugins.html#Mapping_Complex_Objects)
  */
-data class ScalarConverter(
+class ScalarConverter {
     /** Fully qualified class name of a custom scalar type, e.g. java.util.UUID */
-    val type: String,
+    @Parameter
+    lateinit var type: String
+
     /** Fully qualified class name of a custom converter used to convert to/from raw JSON and [type] */
-    val converter: String
-)
+    @Parameter
+    lateinit var converter: String
+}